TY  - CONF
AU  - Gnjatović, Nebojša
AU  - Bošnjak, Srđan
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
AU  - Urošević, Marko
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5001
AB  - Stackers-reclaimers represent the mechanization backbone of high-capacity storages for granular materials. The paper presents the design of a gantry bucket chain stackers-reclaimer for handling of crushed gypsum, as well as the working technology, finite element strength calculation for the main substructures: the working device, the trolley and the gantry. Failureless operation of the presented stacker-reclaimer represent an indirect validation of not only the presented results, but also the entire project as well as the applied technology of manufacture and montage.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proceedings of the XXIV International Conference MHCL’22
T1  - Gantry Bucket Chain Stacker- Reclaimer for Crushed Gypsum
EP  - 60
SP  - 55
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5001
ER  - 

@conference{
author = "Gnjatović, Nebojša and Bošnjak, Srđan and Milenović, Ivan Lj. and Stefanović, Aleksandar Z. and Urošević, Marko",
year = "2022",
abstract = "Stackers-reclaimers represent the mechanization backbone of high-capacity storages for granular materials. The paper presents the design of a gantry bucket chain stackers-reclaimer for handling of crushed gypsum, as well as the working technology, finite element strength calculation for the main substructures: the working device, the trolley and the gantry. Failureless operation of the presented stacker-reclaimer represent an indirect validation of not only the presented results, but also the entire project as well as the applied technology of manufacture and montage.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proceedings of the XXIV International Conference MHCL’22",
title = "Gantry Bucket Chain Stacker- Reclaimer for Crushed Gypsum",
pages = "60-55",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5001"
}

Gnjatović, N., Bošnjak, S., Milenović, I. Lj., Stefanović, A. Z.,& Urošević, M.. (2022). Gantry Bucket Chain Stacker- Reclaimer for Crushed Gypsum. in Proceedings of the XXIV International Conference MHCL’22
University of Belgrade, Faculty of Mechanical Engineering., 55-60.
https://hdl.handle.net/21.15107/rcub_machinery_5001

Gnjatović N, Bošnjak S, Milenović IL, Stefanović AZ, Urošević M. Gantry Bucket Chain Stacker- Reclaimer for Crushed Gypsum. in Proceedings of the XXIV International Conference MHCL’22. 2022;:55-60.
https://hdl.handle.net/21.15107/rcub_machinery_5001 .

Gnjatović, Nebojša, Bošnjak, Srđan, Milenović, Ivan Lj., Stefanović, Aleksandar Z., Urošević, Marko, "Gantry Bucket Chain Stacker- Reclaimer for Crushed Gypsum" in Proceedings of the XXIV International Conference MHCL’22 (2022):55-60,
https://hdl.handle.net/21.15107/rcub_machinery_5001 .

TY  - GEN
AU  - Bošnjak, Srđan
AU  - Čolović, Vladan
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5046
AB  - Одлагачи, заједно са роторним багерима , припадају класи највећих копнених самоходних машина и чине окосницу система површинске експлоатације. Поменути системи представљају једно од најзначајнијих достигнућа у рударству XX века, чији је значај упоредив са значајем који је за рударе XIX века имало откриће и примена динамита.
Основни проблем који се решава применом техничког решења јесте проблем чврстоће и еластичне стабилности носеће конструкције ослоне гусенице међутранспортера одлагача (тзв. „мали транспорт“) PA 200‐2200/2000 (произвођач SANDVIK; укупна маса 1737 t; теоријски капацитет 8800 m3/h), који је у експлоатацију уведен 2016. године. У IV БТО (Багер‐Тракасти транспортер‐Одлагач) систему Површинског копа „Поље Ц“ (РБ „Колубара“) спрегнут је са роторним багером SchRs 1400 (произвођач KRUPP), теоријског капацитета 6600 m3/h. Иако је очекивани век носеће конструкције 50 година, већ након четири године експлоатације дошло је до тешке хаварије (01.07. 2020. године) носеће конструкције ослоне гусенице међутранспортера, што је праћено делимичним ослањањем на тло пријемног транспортера, као и међутранспортера. Хаварија се десила током транспорта, односно промене локације машине.
Током хаварије, најтежа оштећења доживели су елементи структуре попречног носача у зони везе са носачем круте гусенице. Са обе стране дошло је до гужвања правоугаоних вертикалних лимова и избочавања трапезних вертикалних лимова, што је праћено и пуцањем заварених веза. Истовремено, хоризонтални горњи појасни лим у потпуности је изгубио првобитну форму. Због отказа завртањске везе носача погонског мотора, дошло је до његовог пада на тло. Осим тога, код круте гусенице уочени су и ломови гусеничних чланака. Зглобна гусеница је претрпела незнатна оштећења.
Проблем који се решава техничким решењем јесте недовољна чврстоћа и еластична стабилност структуре ослоне гусенице међутранспортера одлагача савремене концепције.
Комплексност поменутог проблема проистиче из:
•	променљивости геометријске конфигурације машине, како током радног процеса, тако и
•	током транспорта;
•	релативно великог броја комбинација парцијалних оптерећења;
•	вишеструких ограничења (просторних и технолошких, пре свега) скупа могућих решења.
Осим код одлагача PA 200‐2200/2000, развијено техничко решење успешно је примењено и за парцијалну реконструкцију структуре ослоне гусенице међутранспортера одлагача PA 200‐2400/2200 (РБ „Колубара“, Површински коп „Тамнава Западно поље“, III БТО систем) истог произвођача (SANDVIK).
О значају примене техничког решења које, посебно имајући у виду актуелно стање основне рударске механизације у ЕПС‐у, изузетно доприноси стабилизацији производње откривке као предуслова за експлоатацију угља, упечатљиво говори чињеница да је у укупној производњи електричне енергије у Србији доминантно учешће (око 70% [6,7]) електричне енергије добијене из лигнита.
PB  - University of Belgrade, Faculty of Mechanical Engineering
T2  - ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)
T1  - Унапређење структуре ослоне гусенице међутранспортера одлагача
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5046
ER  - 

@misc{
author = "Bošnjak, Srđan and Čolović, Vladan and Gnjatović, Nebojša and Milenović, Ivan Lj. and Stefanović, Aleksandar Z.",
year = "2022",
abstract = "Одлагачи, заједно са роторним багерима , припадају класи највећих копнених самоходних машина и чине окосницу система површинске експлоатације. Поменути системи представљају једно од најзначајнијих достигнућа у рударству XX века, чији је значај упоредив са значајем који је за рударе XIX века имало откриће и примена динамита.
Основни проблем који се решава применом техничког решења јесте проблем чврстоће и еластичне стабилности носеће конструкције ослоне гусенице међутранспортера одлагача (тзв. „мали транспорт“) PA 200‐2200/2000 (произвођач SANDVIK; укупна маса 1737 t; теоријски капацитет 8800 m3/h), који је у експлоатацију уведен 2016. године. У IV БТО (Багер‐Тракасти транспортер‐Одлагач) систему Површинског копа „Поље Ц“ (РБ „Колубара“) спрегнут је са роторним багером SchRs 1400 (произвођач KRUPP), теоријског капацитета 6600 m3/h. Иако је очекивани век носеће конструкције 50 година, већ након четири године експлоатације дошло је до тешке хаварије (01.07. 2020. године) носеће конструкције ослоне гусенице међутранспортера, што је праћено делимичним ослањањем на тло пријемног транспортера, као и међутранспортера. Хаварија се десила током транспорта, односно промене локације машине.
Током хаварије, најтежа оштећења доживели су елементи структуре попречног носача у зони везе са носачем круте гусенице. Са обе стране дошло је до гужвања правоугаоних вертикалних лимова и избочавања трапезних вертикалних лимова, што је праћено и пуцањем заварених веза. Истовремено, хоризонтални горњи појасни лим у потпуности је изгубио првобитну форму. Због отказа завртањске везе носача погонског мотора, дошло је до његовог пада на тло. Осим тога, код круте гусенице уочени су и ломови гусеничних чланака. Зглобна гусеница је претрпела незнатна оштећења.
Проблем који се решава техничким решењем јесте недовољна чврстоћа и еластична стабилност структуре ослоне гусенице међутранспортера одлагача савремене концепције.
Комплексност поменутог проблема проистиче из:
•	променљивости геометријске конфигурације машине, како током радног процеса, тако и
•	током транспорта;
•	релативно великог броја комбинација парцијалних оптерећења;
•	вишеструких ограничења (просторних и технолошких, пре свега) скупа могућих решења.
Осим код одлагача PA 200‐2200/2000, развијено техничко решење успешно је примењено и за парцијалну реконструкцију структуре ослоне гусенице међутранспортера одлагача PA 200‐2400/2200 (РБ „Колубара“, Површински коп „Тамнава Западно поље“, III БТО систем) истог произвођача (SANDVIK).
О значају примене техничког решења које, посебно имајући у виду актуелно стање основне рударске механизације у ЕПС‐у, изузетно доприноси стабилизацији производње откривке као предуслова за експлоатацију угља, упечатљиво говори чињеница да је у укупној производњи електричне енергије у Србији доминантно учешће (око 70% [6,7]) електричне енергије добијене из лигнита.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)",
title = "Унапређење структуре ослоне гусенице међутранспортера одлагача",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5046"
}

Bošnjak, S., Čolović, V., Gnjatović, N., Milenović, I. Lj.,& Stefanović, A. Z.. (2022). Унапређење структуре ослоне гусенице међутранспортера одлагача. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)
University of Belgrade, Faculty of Mechanical Engineering..
https://hdl.handle.net/21.15107/rcub_machinery_5046

Bošnjak S, Čolović V, Gnjatović N, Milenović IL, Stefanović AZ. Унапређење структуре ослоне гусенице међутранспортера одлагача. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82). 2022;.
https://hdl.handle.net/21.15107/rcub_machinery_5046 .

Bošnjak, Srđan, Čolović, Vladan, Gnjatović, Nebojša, Milenović, Ivan Lj., Stefanović, Aleksandar Z., "Унапређење структуре ослоне гусенице међутранспортера одлагача" in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82) (2022),
https://hdl.handle.net/21.15107/rcub_machinery_5046 .

TY  - JOUR
AU  - Milenović, Ivan Lj.
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Obradović, Aleksandar
PY  - 2022
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3732
AB  - Identification of the basic parameters of static stability (BPSS) of the slewing superstructure is the key step in solving the problem of its static stability, as well as static stability of the entire bucket wheel excavator (BWE). Specificity of the slewing superstructure examined in this paper lies in the kinematic breakdown system (KBS) which prevents the loss of static stability on the counterweight side. Development of a unique method for the formation and two-step validation of the calculation models for this particular design concept was the main objective of the presented research. A two-step validation of the analytical models is conducted based on the experimental results. As the outcome, the final calculation model formed in such manner represents an accurate basis both for the proof of static stability and for the monitoring of the BPSS during exploitation. By comparing the results of the control weighing and the referent values of the final calculation model it was concluded that the existing double-walled bucket wheel represents a 'weak point' of the considered BWE.
PB  - Polish Maintenance Soc, Lublin
T2  - Eksploatacja I Niezawodnosc-Maintenance and Reliability
T1  - Bucket wheel excavators with a kinematic breakdown system: Identification and monitoring of the basic parameters of static stability of the slewing superstructure
EP  - 370
IS  - 2
SP  - 359
VL  - 24
DO  - 10.17531/ein.2022.2.17
ER  - 

@article{
author = "Milenović, Ivan Lj. and Bošnjak, Srđan and Gnjatović, Nebojša and Obradović, Aleksandar",
year = "2022",
abstract = "Identification of the basic parameters of static stability (BPSS) of the slewing superstructure is the key step in solving the problem of its static stability, as well as static stability of the entire bucket wheel excavator (BWE). Specificity of the slewing superstructure examined in this paper lies in the kinematic breakdown system (KBS) which prevents the loss of static stability on the counterweight side. Development of a unique method for the formation and two-step validation of the calculation models for this particular design concept was the main objective of the presented research. A two-step validation of the analytical models is conducted based on the experimental results. As the outcome, the final calculation model formed in such manner represents an accurate basis both for the proof of static stability and for the monitoring of the BPSS during exploitation. By comparing the results of the control weighing and the referent values of the final calculation model it was concluded that the existing double-walled bucket wheel represents a 'weak point' of the considered BWE.",
publisher = "Polish Maintenance Soc, Lublin",
journal = "Eksploatacja I Niezawodnosc-Maintenance and Reliability",
title = "Bucket wheel excavators with a kinematic breakdown system: Identification and monitoring of the basic parameters of static stability of the slewing superstructure",
pages = "370-359",
number = "2",
volume = "24",
doi = "10.17531/ein.2022.2.17"
}

Milenović, I. Lj., Bošnjak, S., Gnjatović, N.,& Obradović, A.. (2022). Bucket wheel excavators with a kinematic breakdown system: Identification and monitoring of the basic parameters of static stability of the slewing superstructure. in Eksploatacja I Niezawodnosc-Maintenance and Reliability
Polish Maintenance Soc, Lublin., 24(2), 359-370.
https://doi.org/10.17531/ein.2022.2.17

Milenović IL, Bošnjak S, Gnjatović N, Obradović A. Bucket wheel excavators with a kinematic breakdown system: Identification and monitoring of the basic parameters of static stability of the slewing superstructure. in Eksploatacja I Niezawodnosc-Maintenance and Reliability. 2022;24(2):359-370.
doi:10.17531/ein.2022.2.17 .

Milenović, Ivan Lj., Bošnjak, Srđan, Gnjatović, Nebojša, Obradović, Aleksandar, "Bucket wheel excavators with a kinematic breakdown system: Identification and monitoring of the basic parameters of static stability of the slewing superstructure" in Eksploatacja I Niezawodnosc-Maintenance and Reliability, 24, no. 2 (2022):359-370,
https://doi.org/10.17531/ein.2022.2.17 . .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Zrnić, Nenad
AU  - Momčilović, Dejan B.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3400
AB  - Tie-rods of the bucket wheel and counterweight booms are vital parts of the bucket wheel excavator slewing superstructure. This paper is dedicated to the problem of identifying the stress state of the critical cross-section ('net section') of the eye plates on these tie-rods. It presents the results of the experimental and numerical investigations carried out on the eyebar model. The results show the appearance of a plastic deformation in the zone near the contour of the hole even when the eye is subjected to the loads within the range of the permissible loads prescribed by the standard DIN 22261-2. Plastification in the eye net section occurs across the full thickness of the plate, but it does not jeopardize the integrity of the structure. The stress value in the eye net section, calculated in accordance with the standard DIN 22261-2, is significantly lower than the actual stress values around the hole and serves only as a comparative value for the static strength proof for the eye.
PB  - Elsevier Sci Ltd, Oxford
T2  - Engineering Structures
T1  - Tie-rods of the bucket wheel excavator slewing superstructure: A study of the eye plate stress state
VL  - 207
DO  - 10.1016/j.engstruct.2020.110233
ER  - 

@article{
author = "Bošnjak, Srđan and Zrnić, Nenad and Momčilović, Dejan B. and Gnjatović, Nebojša and Milenović, Ivan Lj.",
year = "2020",
abstract = "Tie-rods of the bucket wheel and counterweight booms are vital parts of the bucket wheel excavator slewing superstructure. This paper is dedicated to the problem of identifying the stress state of the critical cross-section ('net section') of the eye plates on these tie-rods. It presents the results of the experimental and numerical investigations carried out on the eyebar model. The results show the appearance of a plastic deformation in the zone near the contour of the hole even when the eye is subjected to the loads within the range of the permissible loads prescribed by the standard DIN 22261-2. Plastification in the eye net section occurs across the full thickness of the plate, but it does not jeopardize the integrity of the structure. The stress value in the eye net section, calculated in accordance with the standard DIN 22261-2, is significantly lower than the actual stress values around the hole and serves only as a comparative value for the static strength proof for the eye.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Engineering Structures",
title = "Tie-rods of the bucket wheel excavator slewing superstructure: A study of the eye plate stress state",
volume = "207",
doi = "10.1016/j.engstruct.2020.110233"
}

Bošnjak, S., Zrnić, N., Momčilović, D. B., Gnjatović, N.,& Milenović, I. Lj.. (2020). Tie-rods of the bucket wheel excavator slewing superstructure: A study of the eye plate stress state. in Engineering Structures
Elsevier Sci Ltd, Oxford., 207.
https://doi.org/10.1016/j.engstruct.2020.110233

Bošnjak S, Zrnić N, Momčilović DB, Gnjatović N, Milenović IL. Tie-rods of the bucket wheel excavator slewing superstructure: A study of the eye plate stress state. in Engineering Structures. 2020;207.
doi:10.1016/j.engstruct.2020.110233 .

Bošnjak, Srđan, Zrnić, Nenad, Momčilović, Dejan B., Gnjatović, Nebojša, Milenović, Ivan Lj., "Tie-rods of the bucket wheel excavator slewing superstructure: A study of the eye plate stress state" in Engineering Structures, 207 (2020),
https://doi.org/10.1016/j.engstruct.2020.110233 . .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Stefanović, Aleksandar Z.
AU  - Milenović, Ivan Lj.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4940
AB  - The design concept of temporary leaning of the gas oil storage tank bearing structure used during substitution of the worn out section of the bottom plates in the zone of the central column support is presented in the paper. On the basis of comparative analysis of the results obtained using finite element structural calculations of the designed state and the state of the central column leaning on the temporary supports, it was determined that by the implementation of the temporary support, the stress-strain state of the bearing structure, which corresponds to the designed stress-strain state of the construction, is obtained. Besides, the strength proof of the structure of temporary support including its welded joint to the central column is also presented in the paper.
PB  - SaTCIP
C3  - 20th International Conference "Research and Development in Mechanical Industry" RaDMI-2020
T1  - Temporary Leaning of the Gas Oil Storage Tank Structure During Bottom Sanation
EP  - 10
SP  - 1
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4940
ER  - 

@conference{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Stefanović, Aleksandar Z. and Milenović, Ivan Lj.",
year = "2020",
abstract = "The design concept of temporary leaning of the gas oil storage tank bearing structure used during substitution of the worn out section of the bottom plates in the zone of the central column support is presented in the paper. On the basis of comparative analysis of the results obtained using finite element structural calculations of the designed state and the state of the central column leaning on the temporary supports, it was determined that by the implementation of the temporary support, the stress-strain state of the bearing structure, which corresponds to the designed stress-strain state of the construction, is obtained. Besides, the strength proof of the structure of temporary support including its welded joint to the central column is also presented in the paper.",
publisher = "SaTCIP",
journal = "20th International Conference "Research and Development in Mechanical Industry" RaDMI-2020",
title = "Temporary Leaning of the Gas Oil Storage Tank Structure During Bottom Sanation",
pages = "10-1",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4940"
}

Bošnjak, S., Gnjatović, N., Stefanović, A. Z.,& Milenović, I. Lj.. (2020). Temporary Leaning of the Gas Oil Storage Tank Structure During Bottom Sanation. in 20th International Conference "Research and Development in Mechanical Industry" RaDMI-2020
SaTCIP., 1-10.
https://hdl.handle.net/21.15107/rcub_machinery_4940

Bošnjak S, Gnjatović N, Stefanović AZ, Milenović IL. Temporary Leaning of the Gas Oil Storage Tank Structure During Bottom Sanation. in 20th International Conference "Research and Development in Mechanical Industry" RaDMI-2020. 2020;:1-10.
https://hdl.handle.net/21.15107/rcub_machinery_4940 .

Bošnjak, Srđan, Gnjatović, Nebojša, Stefanović, Aleksandar Z., Milenović, Ivan Lj., "Temporary Leaning of the Gas Oil Storage Tank Structure During Bottom Sanation" in 20th International Conference "Research and Development in Mechanical Industry" RaDMI-2020 (2020):1-10,
https://hdl.handle.net/21.15107/rcub_machinery_4940 .

TY  - CONF
AU  - Gašić, Vlada
AU  - Milenović, Ivan Lj.
AU  - Jovanović, Miloš
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4539
AB  - The paper deals with the structural optimization of the cantilever girder. Standard CAD
optimization tool is used for the model of the main girder on a large jib crane. The objective
function is the minimum weight of the girder subjected to the given payload, while constraint
functions are postulated according to the usual structural rules and regulations. The illustrative
example shows an easy way of optimization which can be used in everyday CAD designing practice.
It gives practical recommendations in the selection of variable parameters. The obtained results
indicate that the algorithm is time-saving when compared to the analytical approach, especially
when variability of the section needs to be included in the design.
PB  - Serbian Society for Geometry and Graphics (SUGIG)
PB  - University of Belgrade: Faculty of Mechanical Engineering
C3  - The 7th International Scientific Conference on Geometry and Graphics - moNGeomatrija2020, September 18th – 21st 2020, Belgrade, Serbia
T1  - CAD Structural Optimization of Large Cantilever Girders on Cranes
EP  - 320
SP  - 315
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4539
ER  - 

@conference{
author = "Gašić, Vlada and Milenović, Ivan Lj. and Jovanović, Miloš",
year = "2020",
abstract = "The paper deals with the structural optimization of the cantilever girder. Standard CAD
optimization tool is used for the model of the main girder on a large jib crane. The objective
function is the minimum weight of the girder subjected to the given payload, while constraint
functions are postulated according to the usual structural rules and regulations. The illustrative
example shows an easy way of optimization which can be used in everyday CAD designing practice.
It gives practical recommendations in the selection of variable parameters. The obtained results
indicate that the algorithm is time-saving when compared to the analytical approach, especially
when variability of the section needs to be included in the design.",
publisher = "Serbian Society for Geometry and Graphics (SUGIG), University of Belgrade: Faculty of Mechanical Engineering",
journal = "The 7th International Scientific Conference on Geometry and Graphics - moNGeomatrija2020, September 18th – 21st 2020, Belgrade, Serbia",
title = "CAD Structural Optimization of Large Cantilever Girders on Cranes",
pages = "320-315",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4539"
}

Gašić, V., Milenović, I. Lj.,& Jovanović, M.. (2020). CAD Structural Optimization of Large Cantilever Girders on Cranes. in The 7th International Scientific Conference on Geometry and Graphics - moNGeomatrija2020, September 18th – 21st 2020, Belgrade, Serbia
Serbian Society for Geometry and Graphics (SUGIG)., 315-320.
https://hdl.handle.net/21.15107/rcub_machinery_4539

Gašić V, Milenović IL, Jovanović M. CAD Structural Optimization of Large Cantilever Girders on Cranes. in The 7th International Scientific Conference on Geometry and Graphics - moNGeomatrija2020, September 18th – 21st 2020, Belgrade, Serbia. 2020;:315-320.
https://hdl.handle.net/21.15107/rcub_machinery_4539 .

Gašić, Vlada, Milenović, Ivan Lj., Jovanović, Miloš, "CAD Structural Optimization of Large Cantilever Girders on Cranes" in The 7th International Scientific Conference on Geometry and Graphics - moNGeomatrija2020, September 18th – 21st 2020, Belgrade, Serbia (2020):315-320,
https://hdl.handle.net/21.15107/rcub_machinery_4539 .

TY  - GEN
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5041
AB  - Одговор на питање „шта радити након вагања горње градње?“ дат је једино у [7] (страна 233): „Уколико се резултати вагања разликују за више од 5% од теоријских‐прорачунских вредности усвојених за анализу стабилности, мора се проверити прорачун и поновити процедура вагања. Након тога, мора се извршити корекција баласта тако да положај тежишта одговара прорачунским вредностима.“ Дакле, одговор је начелног карактера, уз напомену да су масе обртне горње градње код роторних багера средње величине (класе), који доминирају на српским угљенокопима око 1000 t, при чему се пројектоване масе баласта крећу у распону од 175 t (роторни багер SRs 2000) до 500 t (роторни багер SchRs 1760).
С обзиром на изузетан значај проблема статичке стабилности, техничким решењем уведена је класификација модела обртне горње градње у две основне групе, модели 'а приори' и модели 'а постериори' и дат поступак трансформације прорачунског модела 'а приори' (пројектована слика обртне горње градње) у прорачунски модел 'а постериори' (стварна слика обртне градње). Основне фазе нове методе прорачуна статичке стабилности обртне горње градње ('а постериори') су:
1.	усклађивање прорачунског модела са свим изменама насталим током развоја пројекта и извођења монтаже, односно формирање прорачунског модела 'а приори';
2.	прво вагање, непосредно након завршене монтаже;
3.	израчунавање тежине и положаја тежишта модела 'а приори' за мерне положаје стреле ротора;
4.	израчунавање корективне масе, као и њеног положаја, на основу резултата првог мерења;
5.	формирање прорачунског модела 'а постериори' узимајући у обзир и утицај корективне масе;
6.	валидација прорачунског модела 'а постериори' на основу резултата првог мерења;
7.	одређивање потребне корекције масе противтега и подешених вредности сила у ужадима механизма за промену угла нагиба стреле ротора, на основу резултата прорачуна стабилности изведених на моделу 'а постериори';
8.	друго (контролно) мерење са коригованом масом противтега;
9.	израчунавање тежине и положаја тежишта модела 'а постериори' за положаје стреле ротора током мерења 2;
10.	коначна валидација модела 'а постериори' на основу резултата другог мерења;
11.	коначни прорачун минималних вредности степена сигурности против претурања, на целокупном домену угла нагиба стреле ротора, коришћењем модела 'а постериори'. 
	Модели 'а постериори' од изузетне су важности и за успешну и поуздану експлоатацију машине зато што представљају основу за:
•	подешавање и контролу граничних вредности сила у ужадима механизма за промену угла нагиба стреле ротора;
•	периодичну контролу тежине и положаја тежишта;
•	евентуалне реконструкције са циљем да се оствари оптимално прилагођавање машине условима рада;
што је посебно значајно због чињенице да су роторни багери и одлагачи машине намењене за вишедеценијску експлоатацију.
Коначно, суштину техничког решења, уз детаљан приказ механичког и математичког модела, аутори су 2018. године публиковали у часопису Eksploatacja i Niezawodnosc – Maintenance and Reliability (категорија М22, IF2018=1.806), као рад под називом „From ‘a priori’ to ‘a posteriori’ static stability of the slewing superstructure of a bucket wheel excavator“, Прилог 3 (http://dx.doi.org/10.17531/ein.2018.2.04). Наведени рад представља први рад из области статичке стабилности роторних багера и сродних машина објављен у часопису са SCI листе, што доказује научни потенцијал техничког решења.
PB  - University of Belgrade, Faculty of Mechanical Engineering
T2  - ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)
T1  - Од а приори до а постериори статичке стабилности роторних багера
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5041
ER  - 

@misc{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Milenović, Ivan Lj.",
year = "2020",
abstract = "Одговор на питање „шта радити након вагања горње градње?“ дат је једино у [7] (страна 233): „Уколико се резултати вагања разликују за више од 5% од теоријских‐прорачунских вредности усвојених за анализу стабилности, мора се проверити прорачун и поновити процедура вагања. Након тога, мора се извршити корекција баласта тако да положај тежишта одговара прорачунским вредностима.“ Дакле, одговор је начелног карактера, уз напомену да су масе обртне горње градње код роторних багера средње величине (класе), који доминирају на српским угљенокопима око 1000 t, при чему се пројектоване масе баласта крећу у распону од 175 t (роторни багер SRs 2000) до 500 t (роторни багер SchRs 1760).
С обзиром на изузетан значај проблема статичке стабилности, техничким решењем уведена је класификација модела обртне горње градње у две основне групе, модели 'а приори' и модели 'а постериори' и дат поступак трансформације прорачунског модела 'а приори' (пројектована слика обртне горње градње) у прорачунски модел 'а постериори' (стварна слика обртне градње). Основне фазе нове методе прорачуна статичке стабилности обртне горње градње ('а постериори') су:
1.	усклађивање прорачунског модела са свим изменама насталим током развоја пројекта и извођења монтаже, односно формирање прорачунског модела 'а приори';
2.	прво вагање, непосредно након завршене монтаже;
3.	израчунавање тежине и положаја тежишта модела 'а приори' за мерне положаје стреле ротора;
4.	израчунавање корективне масе, као и њеног положаја, на основу резултата првог мерења;
5.	формирање прорачунског модела 'а постериори' узимајући у обзир и утицај корективне масе;
6.	валидација прорачунског модела 'а постериори' на основу резултата првог мерења;
7.	одређивање потребне корекције масе противтега и подешених вредности сила у ужадима механизма за промену угла нагиба стреле ротора, на основу резултата прорачуна стабилности изведених на моделу 'а постериори';
8.	друго (контролно) мерење са коригованом масом противтега;
9.	израчунавање тежине и положаја тежишта модела 'а постериори' за положаје стреле ротора током мерења 2;
10.	коначна валидација модела 'а постериори' на основу резултата другог мерења;
11.	коначни прорачун минималних вредности степена сигурности против претурања, на целокупном домену угла нагиба стреле ротора, коришћењем модела 'а постериори'. 
	Модели 'а постериори' од изузетне су важности и за успешну и поуздану експлоатацију машине зато што представљају основу за:
•	подешавање и контролу граничних вредности сила у ужадима механизма за промену угла нагиба стреле ротора;
•	периодичну контролу тежине и положаја тежишта;
•	евентуалне реконструкције са циљем да се оствари оптимално прилагођавање машине условима рада;
што је посебно значајно због чињенице да су роторни багери и одлагачи машине намењене за вишедеценијску експлоатацију.
Коначно, суштину техничког решења, уз детаљан приказ механичког и математичког модела, аутори су 2018. године публиковали у часопису Eksploatacja i Niezawodnosc – Maintenance and Reliability (категорија М22, IF2018=1.806), као рад под називом „From ‘a priori’ to ‘a posteriori’ static stability of the slewing superstructure of a bucket wheel excavator“, Прилог 3 (http://dx.doi.org/10.17531/ein.2018.2.04). Наведени рад представља први рад из области статичке стабилности роторних багера и сродних машина објављен у часопису са SCI листе, што доказује научни потенцијал техничког решења.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)",
title = "Од а приори до а постериори статичке стабилности роторних багера",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5041"
}

Bošnjak, S., Gnjatović, N.,& Milenović, I. Lj.. (2020). Од а приори до а постериори статичке стабилности роторних багера. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82)
University of Belgrade, Faculty of Mechanical Engineering..
https://hdl.handle.net/21.15107/rcub_machinery_5041

Bošnjak S, Gnjatović N, Milenović IL. Од а приори до а постериори статичке стабилности роторних багера. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82). 2020;.
https://hdl.handle.net/21.15107/rcub_machinery_5041 .

Bošnjak, Srđan, Gnjatović, Nebojša, Milenović, Ivan Lj., "Од а приори до а постериори статичке стабилности роторних багера" in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М82) (2020),
https://hdl.handle.net/21.15107/rcub_machinery_5041 .

TY  - JOUR
AU  - Gnjatović, Nebojša
AU  - Bošnjak, Srđan
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3337
AB  - An original method for validation of the number of buckets on the working device of a bucket wheel excavator based on the dynamic response of its slewing superstructure (SS) is presented. A set of 16 seemingly acceptable solutions which satisfied the rigid design restrictions, based on the preservation of the existing (a) bucket wheel drivetrain, (b) theoretical capacity, (c) characteristics of the excavated soil and (d) position of the superstructure centre of gravity (CoG), was analysed. Already on the basis of the limiting vertical and lateral accelerations of the bucket wheel centre, which represents a well-grounded indicator of its dynamic behaviour prescribed by the code DIN 22261-2, 14 out of 16 analysed design variants have been discarded, reducing the set of possible solutions to only two - the originally-designed variant (with 17 buckets), and the variant with 20 buckets. Conclusions on the validity of these two design variants were derived on the basis of the dynamic response analysis of the referent points of the SS. The analysis of the impact of soiling on the dynamic response of the SS has shown that negative dynamic effects, observed in the preceding analysis of the originally-designed solution, increase with the amount of the adhered material. Although the redesigned variant with 20 buckets has proven as the only suitable solution from the standpoint of dynamic behaviour of the SS, the results have to be assessed carefully due to the fact that the reduction of the mass of the bucket wheel steel structure by more than 14% leads to the appearance of unfavourable dynamic effects, even though the SS CoG position is preserved.
PB  - Elsevier Sci Ltd, Oxford
T2  - Engineering Structures
T1  - Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets
VL  - 225
DO  - 10.1016/j.engstruct.2020.111313
ER  - 

@article{
author = "Gnjatović, Nebojša and Bošnjak, Srđan and Milenović, Ivan Lj. and Stefanović, Aleksandar Z.",
year = "2020",
abstract = "An original method for validation of the number of buckets on the working device of a bucket wheel excavator based on the dynamic response of its slewing superstructure (SS) is presented. A set of 16 seemingly acceptable solutions which satisfied the rigid design restrictions, based on the preservation of the existing (a) bucket wheel drivetrain, (b) theoretical capacity, (c) characteristics of the excavated soil and (d) position of the superstructure centre of gravity (CoG), was analysed. Already on the basis of the limiting vertical and lateral accelerations of the bucket wheel centre, which represents a well-grounded indicator of its dynamic behaviour prescribed by the code DIN 22261-2, 14 out of 16 analysed design variants have been discarded, reducing the set of possible solutions to only two - the originally-designed variant (with 17 buckets), and the variant with 20 buckets. Conclusions on the validity of these two design variants were derived on the basis of the dynamic response analysis of the referent points of the SS. The analysis of the impact of soiling on the dynamic response of the SS has shown that negative dynamic effects, observed in the preceding analysis of the originally-designed solution, increase with the amount of the adhered material. Although the redesigned variant with 20 buckets has proven as the only suitable solution from the standpoint of dynamic behaviour of the SS, the results have to be assessed carefully due to the fact that the reduction of the mass of the bucket wheel steel structure by more than 14% leads to the appearance of unfavourable dynamic effects, even though the SS CoG position is preserved.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Engineering Structures",
title = "Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets",
volume = "225",
doi = "10.1016/j.engstruct.2020.111313"
}

Gnjatović, N., Bošnjak, S., Milenović, I. Lj.,& Stefanović, A. Z.. (2020). Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets. in Engineering Structures
Elsevier Sci Ltd, Oxford., 225.
https://doi.org/10.1016/j.engstruct.2020.111313

Gnjatović N, Bošnjak S, Milenović IL, Stefanović AZ. Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets. in Engineering Structures. 2020;225.
doi:10.1016/j.engstruct.2020.111313 .

Gnjatović, Nebojša, Bošnjak, Srđan, Milenović, Ivan Lj., Stefanović, Aleksandar Z., "Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets" in Engineering Structures, 225 (2020),
https://doi.org/10.1016/j.engstruct.2020.111313 . .

TY  - JOUR
AU  - Gnjatović, Nebojša
AU  - Bošnjak, Srđan
AU  - Milenović, Ivan Lj.
PY  - 2020
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/3302
AB  - Exploitation of bucket wheel excavators (BWEs) is accompanied by an increase of mass due to transport and adherence of a large amount of the material. Technical regulations do not account for the dynamic behaviour of BWEs. Such problems are analysed as quasi-static. A procedure and results of investigation of the influence of masses of the bucket wheel (BW) incrustation and soil in a blocked BW chute on the superstructure response are presented. Analysis of sensitivity of dynamic characteristics and the response to adherence of the material is conducted. The method and results can be used in the design stages of new and in reconstructions of obsolete BWEs.
PB  - Polish Soc Theoretical & Applied Mechanics, Warszawa
T2  - Journal of Theoretical and Applied Mechanics
T1  - The influence of incrustation and chute blockage on the dynamic behaviour of a bucket wheel excavator slewing superstructure
EP  - 584
IS  - 3
SP  - 573
VL  - 58
DO  - 10.15632/jtam-pl/121942
ER  - 

@article{
author = "Gnjatović, Nebojša and Bošnjak, Srđan and Milenović, Ivan Lj.",
year = "2020",
abstract = "Exploitation of bucket wheel excavators (BWEs) is accompanied by an increase of mass due to transport and adherence of a large amount of the material. Technical regulations do not account for the dynamic behaviour of BWEs. Such problems are analysed as quasi-static. A procedure and results of investigation of the influence of masses of the bucket wheel (BW) incrustation and soil in a blocked BW chute on the superstructure response are presented. Analysis of sensitivity of dynamic characteristics and the response to adherence of the material is conducted. The method and results can be used in the design stages of new and in reconstructions of obsolete BWEs.",
publisher = "Polish Soc Theoretical & Applied Mechanics, Warszawa",
journal = "Journal of Theoretical and Applied Mechanics",
title = "The influence of incrustation and chute blockage on the dynamic behaviour of a bucket wheel excavator slewing superstructure",
pages = "584-573",
number = "3",
volume = "58",
doi = "10.15632/jtam-pl/121942"
}

Gnjatović, N., Bošnjak, S.,& Milenović, I. Lj.. (2020). The influence of incrustation and chute blockage on the dynamic behaviour of a bucket wheel excavator slewing superstructure. in Journal of Theoretical and Applied Mechanics
Polish Soc Theoretical & Applied Mechanics, Warszawa., 58(3), 573-584.
https://doi.org/10.15632/jtam-pl/121942

Gnjatović N, Bošnjak S, Milenović IL. The influence of incrustation and chute blockage on the dynamic behaviour of a bucket wheel excavator slewing superstructure. in Journal of Theoretical and Applied Mechanics. 2020;58(3):573-584.
doi:10.15632/jtam-pl/121942 .

Gnjatović, Nebojša, Bošnjak, Srđan, Milenović, Ivan Lj., "The influence of incrustation and chute blockage on the dynamic behaviour of a bucket wheel excavator slewing superstructure" in Journal of Theoretical and Applied Mechanics, 58, no. 3 (2020):573-584,
https://doi.org/10.15632/jtam-pl/121942 . .

TY  - CONF
AU  - Arsić, Miodrag
AU  - Bošnjak, Srđan
AU  - Grabulov, Vencislav
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4938
AB  - Damaging of the carrying steel structure and embedding of the rejecting drum of the stacker conveyor occurred during the exploitation of the bucket-wheel reclaimer with the belonging stacker. The analysis of the cause and level of damaging led to the conclusion that damaged parts should be replaced by new ones and that methodology of repair should be based on the application of a suitable welding technology. This paper presents the methodology of repair welding performed during the replacement of the damaged carrying structure and embedding of the rejecting drum of the stacker conveyor which consist of steel sheets and profiles that’s based on the conceptual solution for damage repair through the use of program package ’Catia’ – V5 that enabled the creation of models and graphic documentation of structural parts that should be replaced by new ones. It should also be noted that geodetic survey of the lower belt of the stacker structure was performed after the substitution of damaged parts of the structure.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proceedings of the XXIII International Conference MHCL’19
T1  - Repair methodology for the carrying structure of the rejecting drum of the bucket-wheel reclaimer stacker conveyor at coal landfill
EP  - 122
SP  - 117
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4938
ER  - 

@conference{
author = "Arsić, Miodrag and Bošnjak, Srđan and Grabulov, Vencislav and Gnjatović, Nebojša and Milenović, Ivan Lj.",
year = "2019",
abstract = "Damaging of the carrying steel structure and embedding of the rejecting drum of the stacker conveyor occurred during the exploitation of the bucket-wheel reclaimer with the belonging stacker. The analysis of the cause and level of damaging led to the conclusion that damaged parts should be replaced by new ones and that methodology of repair should be based on the application of a suitable welding technology. This paper presents the methodology of repair welding performed during the replacement of the damaged carrying structure and embedding of the rejecting drum of the stacker conveyor which consist of steel sheets and profiles that’s based on the conceptual solution for damage repair through the use of program package ’Catia’ – V5 that enabled the creation of models and graphic documentation of structural parts that should be replaced by new ones. It should also be noted that geodetic survey of the lower belt of the stacker structure was performed after the substitution of damaged parts of the structure.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proceedings of the XXIII International Conference MHCL’19",
title = "Repair methodology for the carrying structure of the rejecting drum of the bucket-wheel reclaimer stacker conveyor at coal landfill",
pages = "122-117",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4938"
}

Arsić, M., Bošnjak, S., Grabulov, V., Gnjatović, N.,& Milenović, I. Lj.. (2019). Repair methodology for the carrying structure of the rejecting drum of the bucket-wheel reclaimer stacker conveyor at coal landfill. in Proceedings of the XXIII International Conference MHCL’19
University of Belgrade, Faculty of Mechanical Engineering., 117-122.
https://hdl.handle.net/21.15107/rcub_machinery_4938

Arsić M, Bošnjak S, Grabulov V, Gnjatović N, Milenović IL. Repair methodology for the carrying structure of the rejecting drum of the bucket-wheel reclaimer stacker conveyor at coal landfill. in Proceedings of the XXIII International Conference MHCL’19. 2019;:117-122.
https://hdl.handle.net/21.15107/rcub_machinery_4938 .

Arsić, Miodrag, Bošnjak, Srđan, Grabulov, Vencislav, Gnjatović, Nebojša, Milenović, Ivan Lj., "Repair methodology for the carrying structure of the rejecting drum of the bucket-wheel reclaimer stacker conveyor at coal landfill" in Proceedings of the XXIII International Conference MHCL’19 (2019):117-122,
https://hdl.handle.net/21.15107/rcub_machinery_4938 .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
AU  - Urošević, Marko
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4936
AB  - A bucket wheel with drive represents a vital subsystem of any bucket wheel excavator. A multidecadal experience in the exploitation and maintenance of bucket wheel excavators SRs 2000 has imposed a need for modernization and unification of the excavating devices of four of such machines, used for the excavation of overburden in Serbian open pit mines. This paper presents a portion of the research dedicated to the problems of strength and dynamic properties of the bucket wheel boom, static stability of the superstructure as well as installation of the unified design solution for the bucket wheel drive of the bucket wheel excavator SRs 2000. By
installing a modernized design solution of the bucket wheel with drive, i.e. by the means of partial revitalization of the bucket wheel excavator, its exploitational life span is prolonged and, additionally, the level of reliability and availability of the overburden systems is increased, and a
significant reduction in maintenance expenses is achieved.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proceedings of the XXIII International Conference MHCL’19
T1  - Modernization and unification of the excavating devices of bucket wheel excavators SRs 2000 deployed in Serbian open pit mines
EP  - 182
SP  - 175
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4936
ER  - 

@conference{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Milenović, Ivan Lj. and Stefanović, Aleksandar Z. and Urošević, Marko",
year = "2019",
abstract = "A bucket wheel with drive represents a vital subsystem of any bucket wheel excavator. A multidecadal experience in the exploitation and maintenance of bucket wheel excavators SRs 2000 has imposed a need for modernization and unification of the excavating devices of four of such machines, used for the excavation of overburden in Serbian open pit mines. This paper presents a portion of the research dedicated to the problems of strength and dynamic properties of the bucket wheel boom, static stability of the superstructure as well as installation of the unified design solution for the bucket wheel drive of the bucket wheel excavator SRs 2000. By
installing a modernized design solution of the bucket wheel with drive, i.e. by the means of partial revitalization of the bucket wheel excavator, its exploitational life span is prolonged and, additionally, the level of reliability and availability of the overburden systems is increased, and a
significant reduction in maintenance expenses is achieved.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proceedings of the XXIII International Conference MHCL’19",
title = "Modernization and unification of the excavating devices of bucket wheel excavators SRs 2000 deployed in Serbian open pit mines",
pages = "182-175",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4936"
}

Bošnjak, S., Gnjatović, N., Milenović, I. Lj., Stefanović, A. Z.,& Urošević, M.. (2019). Modernization and unification of the excavating devices of bucket wheel excavators SRs 2000 deployed in Serbian open pit mines. in Proceedings of the XXIII International Conference MHCL’19
University of Belgrade, Faculty of Mechanical Engineering., 175-182.
https://hdl.handle.net/21.15107/rcub_machinery_4936

Bošnjak S, Gnjatović N, Milenović IL, Stefanović AZ, Urošević M. Modernization and unification of the excavating devices of bucket wheel excavators SRs 2000 deployed in Serbian open pit mines. in Proceedings of the XXIII International Conference MHCL’19. 2019;:175-182.
https://hdl.handle.net/21.15107/rcub_machinery_4936 .

Bošnjak, Srđan, Gnjatović, Nebojša, Milenović, Ivan Lj., Stefanović, Aleksandar Z., Urošević, Marko, "Modernization and unification of the excavating devices of bucket wheel excavators SRs 2000 deployed in Serbian open pit mines" in Proceedings of the XXIII International Conference MHCL’19 (2019):175-182,
https://hdl.handle.net/21.15107/rcub_machinery_4936 .

TY  - CONF
AU  - Gnjatović, Nebojša
AU  - Bošnjak, Srđan
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
PY  - 2019
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4934
AB  - The method for validation of the number of buckets on the working device of a bucket wheel excavator from the aspect of dynamic behaviour of the system, partially presented in this paper, was developed on the basis of the original spatial reduced dynamic model of the bucket wheel excavator with two masts, which enables modal analysis and analysis of the dynamic
response of the system for continuous variation of constructional parameters and parameters of excitation. The set of 16 seemingly acceptable solutions, all of which satisfied the rigid design restrictions which were: (a) use of the same bucket wheel drivetrain, (b) preservation of the theoretical capacity, (c) possibility of the excavation of soil of the fourth category and (d) preservation of the superstructure centre of gravity position, was analyzed. On the basis of limiting vertical and lateral accelerations, derived from dynamic coefficients prescribed by the code DIN 22261-2, of the bucket wheel centre, which for a proper geometrically-designed bucket wheel excavator structure represents a well grounded indicator of its dynamic behaviour, 14 out of 16 analyzed solutions were discarded, yielding the set of possible solutions to only 2, the originally designed one (with 17 buckets) and the solution with 20 buckets installed on the bucket wheel.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proceedings of the XXIII International Conference MHCL’19
T1  - Validation of the number of buckets on the working device of a bucket wheel
EP  - 196
SP  - 187
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4934
ER  - 

@conference{
author = "Gnjatović, Nebojša and Bošnjak, Srđan and Milenović, Ivan Lj. and Stefanović, Aleksandar Z.",
year = "2019",
abstract = "The method for validation of the number of buckets on the working device of a bucket wheel excavator from the aspect of dynamic behaviour of the system, partially presented in this paper, was developed on the basis of the original spatial reduced dynamic model of the bucket wheel excavator with two masts, which enables modal analysis and analysis of the dynamic
response of the system for continuous variation of constructional parameters and parameters of excitation. The set of 16 seemingly acceptable solutions, all of which satisfied the rigid design restrictions which were: (a) use of the same bucket wheel drivetrain, (b) preservation of the theoretical capacity, (c) possibility of the excavation of soil of the fourth category and (d) preservation of the superstructure centre of gravity position, was analyzed. On the basis of limiting vertical and lateral accelerations, derived from dynamic coefficients prescribed by the code DIN 22261-2, of the bucket wheel centre, which for a proper geometrically-designed bucket wheel excavator structure represents a well grounded indicator of its dynamic behaviour, 14 out of 16 analyzed solutions were discarded, yielding the set of possible solutions to only 2, the originally designed one (with 17 buckets) and the solution with 20 buckets installed on the bucket wheel.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proceedings of the XXIII International Conference MHCL’19",
title = "Validation of the number of buckets on the working device of a bucket wheel",
pages = "196-187",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4934"
}

Gnjatović, N., Bošnjak, S., Milenović, I. Lj.,& Stefanović, A. Z.. (2019). Validation of the number of buckets on the working device of a bucket wheel. in Proceedings of the XXIII International Conference MHCL’19
University of Belgrade, Faculty of Mechanical Engineering., 187-196.
https://hdl.handle.net/21.15107/rcub_machinery_4934

Gnjatović N, Bošnjak S, Milenović IL, Stefanović AZ. Validation of the number of buckets on the working device of a bucket wheel. in Proceedings of the XXIII International Conference MHCL’19. 2019;:187-196.
https://hdl.handle.net/21.15107/rcub_machinery_4934 .

Gnjatović, Nebojša, Bošnjak, Srđan, Milenović, Ivan Lj., Stefanović, Aleksandar Z., "Validation of the number of buckets on the working device of a bucket wheel" in Proceedings of the XXIII International Conference MHCL’19 (2019):187-196,
https://hdl.handle.net/21.15107/rcub_machinery_4934 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2922
AB  - The complexity of the slewing superstructure (SS) balancing problem derives from the changeability of its geometric configuration, the complexity of working conditions as well as multiple limitations of the possible set of solutions. Having in mind the fact that the existing reference literature does not fully specify the procedure of static stability proof, the aforementioned procedure is presented in detail for the first time in this paper. A major contribution is represented in the classification of the slewing superstructure models into two groups which were named: the 'a priori' model (designed image of the SS) and the 'a posteriori' model (actual image of the SS). The fundamental stages of the 'a posteriori' model development method are presented in the paper. The transformation and validation of the calculation model 'a priori' to the calculation model 'a posteriori' was conducted on the basis of weighing results. A calculation of the basic parameters of the bucket wheel excavator (BWE) superstructure was conducted for both analyzed models by using the in-house developed software. The 'a posteriori' models provide a reliable calculation of the SS static stability and may be used not only for static stability proof of the machine as a whole, but also for load analysis of substructures and elements of BWE and related surface mining machines, such as spreaders. Besides that, the previously mentioned models are of extreme importance for a successful and reliable exploitation and maintenence of the machine since they present the basis for adjustment and control of limiting winch rope forces values, periodic control of mass and center of gravity position, as well as for a possible reconstruction which would be conducted in order to realize better customization of the machine versus operating conditions.
PB  - Polish Maintenance Soc, Lublin
T2  - Eksploatacja I Niezawodnosc-Maintenance and Reliability
T1  - From 'a priori' to 'a posteriori' static stability of the slewing superstructure of a bucket wheel excavator
EP  - 206
IS  - 2
SP  - 190
VL  - 20
DO  - 10.17531/ein.2018.2.04
ER  - 

@article{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Milenović, Ivan Lj.",
year = "2018",
abstract = "The complexity of the slewing superstructure (SS) balancing problem derives from the changeability of its geometric configuration, the complexity of working conditions as well as multiple limitations of the possible set of solutions. Having in mind the fact that the existing reference literature does not fully specify the procedure of static stability proof, the aforementioned procedure is presented in detail for the first time in this paper. A major contribution is represented in the classification of the slewing superstructure models into two groups which were named: the 'a priori' model (designed image of the SS) and the 'a posteriori' model (actual image of the SS). The fundamental stages of the 'a posteriori' model development method are presented in the paper. The transformation and validation of the calculation model 'a priori' to the calculation model 'a posteriori' was conducted on the basis of weighing results. A calculation of the basic parameters of the bucket wheel excavator (BWE) superstructure was conducted for both analyzed models by using the in-house developed software. The 'a posteriori' models provide a reliable calculation of the SS static stability and may be used not only for static stability proof of the machine as a whole, but also for load analysis of substructures and elements of BWE and related surface mining machines, such as spreaders. Besides that, the previously mentioned models are of extreme importance for a successful and reliable exploitation and maintenence of the machine since they present the basis for adjustment and control of limiting winch rope forces values, periodic control of mass and center of gravity position, as well as for a possible reconstruction which would be conducted in order to realize better customization of the machine versus operating conditions.",
publisher = "Polish Maintenance Soc, Lublin",
journal = "Eksploatacja I Niezawodnosc-Maintenance and Reliability",
title = "From 'a priori' to 'a posteriori' static stability of the slewing superstructure of a bucket wheel excavator",
pages = "206-190",
number = "2",
volume = "20",
doi = "10.17531/ein.2018.2.04"
}

Bošnjak, S., Gnjatović, N.,& Milenović, I. Lj.. (2018). From 'a priori' to 'a posteriori' static stability of the slewing superstructure of a bucket wheel excavator. in Eksploatacja I Niezawodnosc-Maintenance and Reliability
Polish Maintenance Soc, Lublin., 20(2), 190-206.
https://doi.org/10.17531/ein.2018.2.04

Bošnjak S, Gnjatović N, Milenović IL. From 'a priori' to 'a posteriori' static stability of the slewing superstructure of a bucket wheel excavator. in Eksploatacja I Niezawodnosc-Maintenance and Reliability. 2018;20(2):190-206.
doi:10.17531/ein.2018.2.04 .

Bošnjak, Srđan, Gnjatović, Nebojša, Milenović, Ivan Lj., "From 'a priori' to 'a posteriori' static stability of the slewing superstructure of a bucket wheel excavator" in Eksploatacja I Niezawodnosc-Maintenance and Reliability, 20, no. 2 (2018):190-206,
https://doi.org/10.17531/ein.2018.2.04 . .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Arsić, Miodrag A.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Arsić, Dušan M.
PY  - 2018
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2912
AB  - Buckets are a vital substructure of all digging machines, and are intended for the realisation of the fundamental machine function - soil excavation. This paper presents the results of the experimental-numerical investigation of the cause of the bucket wheel excavator SRs 470 buckets failure. The chemical composition and mechanical properties, the impact toughness, hardness, tendency to cracks and the microstructure were determined using appropriate tests. Experimental examinations of working and residual stresses were performed using strain gauges. The superposition of the experimentally determined working and residual stresses and the calculation of the total principal stresses were conducted using the originally developed procedure presented in this paper. The bucket working stress state was calculated by applying the linear finite element method. Conclusions based on the investigation results show that the main reasons for the buckets failure were the 'design-in defects' - oversights made during the procedures of geometrical shaping and material selection. Furthermore, high values of residual stresses, as well as the cold cracking observed on the welded joint of the knife and the bucket body, suggest that the 'manufacturing-in defects' also played a significant role in the failure. The superposition of influences of the 'design-in defects' and the 'manufacturing-in defects' has conditioned the appearance and propagation of long-term fatigue cracks, leading to the total destruction of the buckets. The fact that buckets' failure appeared due to oversights made during geometrical shaping, material selection and manufacturing further points to the importance of the critical approach implementation during the design phase of the earthmoving machines working devices.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Failure of the bucket wheel excavator buckets
EP  - 261
SP  - 247
VL  - 84
DO  - 10.1016/j.engfailanal.2017.11.017
ER  - 

@article{
author = "Bošnjak, Srđan and Arsić, Miodrag A. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Arsić, Dušan M.",
year = "2018",
abstract = "Buckets are a vital substructure of all digging machines, and are intended for the realisation of the fundamental machine function - soil excavation. This paper presents the results of the experimental-numerical investigation of the cause of the bucket wheel excavator SRs 470 buckets failure. The chemical composition and mechanical properties, the impact toughness, hardness, tendency to cracks and the microstructure were determined using appropriate tests. Experimental examinations of working and residual stresses were performed using strain gauges. The superposition of the experimentally determined working and residual stresses and the calculation of the total principal stresses were conducted using the originally developed procedure presented in this paper. The bucket working stress state was calculated by applying the linear finite element method. Conclusions based on the investigation results show that the main reasons for the buckets failure were the 'design-in defects' - oversights made during the procedures of geometrical shaping and material selection. Furthermore, high values of residual stresses, as well as the cold cracking observed on the welded joint of the knife and the bucket body, suggest that the 'manufacturing-in defects' also played a significant role in the failure. The superposition of influences of the 'design-in defects' and the 'manufacturing-in defects' has conditioned the appearance and propagation of long-term fatigue cracks, leading to the total destruction of the buckets. The fact that buckets' failure appeared due to oversights made during geometrical shaping, material selection and manufacturing further points to the importance of the critical approach implementation during the design phase of the earthmoving machines working devices.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Failure of the bucket wheel excavator buckets",
pages = "261-247",
volume = "84",
doi = "10.1016/j.engfailanal.2017.11.017"
}

Bošnjak, S., Arsić, M. A., Gnjatović, N., Milenović, I. Lj.,& Arsić, D. M.. (2018). Failure of the bucket wheel excavator buckets. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 84, 247-261.
https://doi.org/10.1016/j.engfailanal.2017.11.017

Bošnjak S, Arsić MA, Gnjatović N, Milenović IL, Arsić DM. Failure of the bucket wheel excavator buckets. in Engineering Failure Analysis. 2018;84:247-261.
doi:10.1016/j.engfailanal.2017.11.017 .

Bošnjak, Srđan, Arsić, Miodrag A., Gnjatović, Nebojša, Milenović, Ivan Lj., Arsić, Dušan M., "Failure of the bucket wheel excavator buckets" in Engineering Failure Analysis, 84 (2018):247-261,
https://doi.org/10.1016/j.engfailanal.2017.11.017 . .

TY  - CONF
AU  - Gnjatović, Nebojša
AU  - Pantelić, Milorad
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
AU  - Bošnjak, Srđan
PY  - 2017
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4930
AB  - Bucket wheel excavators (BWEs) are a backbone of any power industry that heavily relies on surface exploitation. As such, any failure, breakdown or collapse of the machine or its subsystems poses a serious drawback in the efficiency of an entire mining system, and is strongly reflected on costs in labour, finances, material and downtime, and is also a potential risk to the safety of workers. This, combined with lengthy lifetime of the machines operating in open cast mines of Serbia (measured in decades), places immense value on the avoidance of potentially hazardous problems during all stages of their lifespan, namely the design, manufacture and exploitation phases. Over the past decades, demand for the ever-increasing capacity and efficiency of BWEs has led to failures which may indicate a need for the reassessment of the calculation methods and guides. This paper presents few such cases, along with the discussion about causes, and suggests an approach to dynamic behaviour analysis based on reduced spatial dynamic models of BWEs which enable modal analysis and the analysis of a dynamic response for continuous variation of constructional parameters.
PB  - Beograd : INSTITUT ZA ISTRAŽIVANJA I PROJEKTOVANJA U PRIVREDI
C3  - Proceedings of the 42nd International scientific conference Maintenance of Machinery and Equipment (OMO 2017)
T1  - Approaches in forensic engineering of excavating units operating on open pit mines of Serbia
EP  - 158
SP  - 148
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4930
ER  - 

@conference{
author = "Gnjatović, Nebojša and Pantelić, Milorad and Milenović, Ivan Lj. and Stefanović, Aleksandar Z. and Bošnjak, Srđan",
year = "2017",
abstract = "Bucket wheel excavators (BWEs) are a backbone of any power industry that heavily relies on surface exploitation. As such, any failure, breakdown or collapse of the machine or its subsystems poses a serious drawback in the efficiency of an entire mining system, and is strongly reflected on costs in labour, finances, material and downtime, and is also a potential risk to the safety of workers. This, combined with lengthy lifetime of the machines operating in open cast mines of Serbia (measured in decades), places immense value on the avoidance of potentially hazardous problems during all stages of their lifespan, namely the design, manufacture and exploitation phases. Over the past decades, demand for the ever-increasing capacity and efficiency of BWEs has led to failures which may indicate a need for the reassessment of the calculation methods and guides. This paper presents few such cases, along with the discussion about causes, and suggests an approach to dynamic behaviour analysis based on reduced spatial dynamic models of BWEs which enable modal analysis and the analysis of a dynamic response for continuous variation of constructional parameters.",
publisher = "Beograd : INSTITUT ZA ISTRAŽIVANJA I PROJEKTOVANJA U PRIVREDI",
journal = "Proceedings of the 42nd International scientific conference Maintenance of Machinery and Equipment (OMO 2017)",
title = "Approaches in forensic engineering of excavating units operating on open pit mines of Serbia",
pages = "158-148",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4930"
}

Gnjatović, N., Pantelić, M., Milenović, I. Lj., Stefanović, A. Z.,& Bošnjak, S.. (2017). Approaches in forensic engineering of excavating units operating on open pit mines of Serbia. in Proceedings of the 42nd International scientific conference Maintenance of Machinery and Equipment (OMO 2017)
Beograd : INSTITUT ZA ISTRAŽIVANJA I PROJEKTOVANJA U PRIVREDI., 148-158.
https://hdl.handle.net/21.15107/rcub_machinery_4930

Gnjatović N, Pantelić M, Milenović IL, Stefanović AZ, Bošnjak S. Approaches in forensic engineering of excavating units operating on open pit mines of Serbia. in Proceedings of the 42nd International scientific conference Maintenance of Machinery and Equipment (OMO 2017). 2017;:148-158.
https://hdl.handle.net/21.15107/rcub_machinery_4930 .

Gnjatović, Nebojša, Pantelić, Milorad, Milenović, Ivan Lj., Stefanović, Aleksandar Z., Bošnjak, Srđan, "Approaches in forensic engineering of excavating units operating on open pit mines of Serbia" in Proceedings of the 42nd International scientific conference Maintenance of Machinery and Equipment (OMO 2017) (2017):148-158,
https://hdl.handle.net/21.15107/rcub_machinery_4930 .

TY  - GEN
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Petković, Zoran D.
AU  - Milojević, Goran
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
PY  - 2017
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5045
AB  - Сопствена тежина подсистема стреле ротора доминантно утиче на интензитет силе у ужету механизма за промену угла нагиба стреле ротора [1]. Осим тога, положај тежишта обртне горње градње значајно утиче на дистрибуцију оптерећења унутар радиаксијалног лежаја којим се обртна горња градња ослања на доњу градњу, а тиме и на његов век [4,5]. На основу изложених чињеница закључује се да прецизна идентификација основних параметара статичке стабилности (ОПСС: тежина и положај тежишта) омогућава: (1) поуздано подешавање граничних вредности сила у ужадима механизма за промену угла нагиба стреле ротора, које представљају основну заштиту од губитка статичке стабилности обртне горње градње; (2) идентификацију оптерећења кука‐хватаљки, које спречавају губитак статичке стабилности у екстремним случајевима оптерећења; (3) одређивање неравномерности оптерећења котрљајних тела радиаксијалног лежаја за ослањање обртне горње градње.
Основне експлоатационе карактеристике, поузданост и безбедност роторних багера доминантно одређују параметри горње градње. Они се могу сврстати у три основне групе: (1) параметри који одређују статичку стабилност горње градње; (2) параметри који одређују чврстоћу горње градње; (3) параметри који одређују динамичко понашање горње градње. Заједнички именитељ свих наведених параметара јесте маса горње градње односно, њена дистрибуција по структури. Зато се одређивању ОПСС, мора посветити посебна пажња у свим фазама пројектовања роторног багера. Чак и код светски реномираних произвођача роторних багера јављају се знатне разлике поменутих параметара горње градње током развоја пројекта, што је најчешће последица накнадних захтева купца, или немогућности набавке пројектом предвиђених компоненти. Управо због тога, након завршетка монтаже машине обавезно се врши експериментално одређивање тежине горње градње и положаја њеног тежишта [7‐10] са циљем да се изврши валидација пројектованих ОПСС [11,12]. Према цитираној литератури, поступак валидације изводи се упоређивањем пројектоване и измерене тежине горње градње. Уколико је разлика измерене и пројектоване тежине већа од 5%, онда се захтева понављање и прорачуна и вагања. О упоређивању положаја тежишта, одређеног аналитички и експериментом, у цитираној литератури нема ни помена. С обзиром на чињеницу да се у литератури [2‐12], као ни у [13‐16], дакле у целокупној литератури и техничкој регулативи која је била доступна ауторима, нигде не наводи могућност спрезања резултата добијених аналитички и експериментом, техничким решењем постављен је оригинални метод формирања аналитичког модела обртне горње градње потпуно усаглашеног са изведеним стањем утврђеним експериментом.
Суштину техничког решења и његову примену код роторног багера SchRs 1600 аутори су
публиковали у часопису Journal of Zhejiang University ‐ SCIENCE A (категорија М22) као рад под називом „Basic parameters of the static stability, loads and strength of the vital parts of the bucket wheel excavator’s slewing superstructure“ (https://doi.org/10.1631/jzus.A1500037), Прилог 3. Поменути рад представља први рад из области идентификације и оцене основних параметара статичке стабилности роторних багера објављен у часопису са SCI листе, што сведочи о научном потенцијалу техничког решења.
PB  - University of Belgrade, Faculty of Mechanical Engineering
T2  - ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М83)
T1  - Примена 3Д модела за аналитичко‐експериментално одређивање параметара статичке стабилности и спољашњег оптерећења роторног багера
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5045
ER  - 

@misc{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Petković, Zoran D. and Milojević, Goran and Milenović, Ivan Lj. and Stefanović, Aleksandar Z.",
year = "2017",
abstract = "Сопствена тежина подсистема стреле ротора доминантно утиче на интензитет силе у ужету механизма за промену угла нагиба стреле ротора [1]. Осим тога, положај тежишта обртне горње градње значајно утиче на дистрибуцију оптерећења унутар радиаксијалног лежаја којим се обртна горња градња ослања на доњу градњу, а тиме и на његов век [4,5]. На основу изложених чињеница закључује се да прецизна идентификација основних параметара статичке стабилности (ОПСС: тежина и положај тежишта) омогућава: (1) поуздано подешавање граничних вредности сила у ужадима механизма за промену угла нагиба стреле ротора, које представљају основну заштиту од губитка статичке стабилности обртне горње градње; (2) идентификацију оптерећења кука‐хватаљки, које спречавају губитак статичке стабилности у екстремним случајевима оптерећења; (3) одређивање неравномерности оптерећења котрљајних тела радиаксијалног лежаја за ослањање обртне горње градње.
Основне експлоатационе карактеристике, поузданост и безбедност роторних багера доминантно одређују параметри горње градње. Они се могу сврстати у три основне групе: (1) параметри који одређују статичку стабилност горње градње; (2) параметри који одређују чврстоћу горње градње; (3) параметри који одређују динамичко понашање горње градње. Заједнички именитељ свих наведених параметара јесте маса горње градње односно, њена дистрибуција по структури. Зато се одређивању ОПСС, мора посветити посебна пажња у свим фазама пројектовања роторног багера. Чак и код светски реномираних произвођача роторних багера јављају се знатне разлике поменутих параметара горње градње током развоја пројекта, што је најчешће последица накнадних захтева купца, или немогућности набавке пројектом предвиђених компоненти. Управо због тога, након завршетка монтаже машине обавезно се врши експериментално одређивање тежине горње градње и положаја њеног тежишта [7‐10] са циљем да се изврши валидација пројектованих ОПСС [11,12]. Према цитираној литератури, поступак валидације изводи се упоређивањем пројектоване и измерене тежине горње градње. Уколико је разлика измерене и пројектоване тежине већа од 5%, онда се захтева понављање и прорачуна и вагања. О упоређивању положаја тежишта, одређеног аналитички и експериментом, у цитираној литератури нема ни помена. С обзиром на чињеницу да се у литератури [2‐12], као ни у [13‐16], дакле у целокупној литератури и техничкој регулативи која је била доступна ауторима, нигде не наводи могућност спрезања резултата добијених аналитички и експериментом, техничким решењем постављен је оригинални метод формирања аналитичког модела обртне горње градње потпуно усаглашеног са изведеним стањем утврђеним експериментом.
Суштину техничког решења и његову примену код роторног багера SchRs 1600 аутори су
публиковали у часопису Journal of Zhejiang University ‐ SCIENCE A (категорија М22) као рад под називом „Basic parameters of the static stability, loads and strength of the vital parts of the bucket wheel excavator’s slewing superstructure“ (https://doi.org/10.1631/jzus.A1500037), Прилог 3. Поменути рад представља први рад из области идентификације и оцене основних параметара статичке стабилности роторних багера објављен у часопису са SCI листе, што сведочи о научном потенцијалу техничког решења.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М83)",
title = "Примена 3Д модела за аналитичко‐експериментално одређивање параметара статичке стабилности и спољашњег оптерећења роторног багера",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5045"
}

Bošnjak, S., Gnjatović, N., Petković, Z. D., Milojević, G., Milenović, I. Lj.,& Stefanović, A. Z.. (2017). Примена 3Д модела за аналитичко‐експериментално одређивање параметара статичке стабилности и спољашњег оптерећења роторног багера. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М83)
University of Belgrade, Faculty of Mechanical Engineering..
https://hdl.handle.net/21.15107/rcub_machinery_5045

Bošnjak S, Gnjatović N, Petković ZD, Milojević G, Milenović IL, Stefanović AZ. Примена 3Д модела за аналитичко‐експериментално одређивање параметара статичке стабилности и спољашњег оптерећења роторног багера. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М83). 2017;.
https://hdl.handle.net/21.15107/rcub_machinery_5045 .

Bošnjak, Srđan, Gnjatović, Nebojša, Petković, Zoran D., Milojević, Goran, Milenović, Ivan Lj., Stefanović, Aleksandar Z., "Примена 3Д модела за аналитичко‐експериментално одређивање параметара статичке стабилности и спољашњег оптерећења роторног багера" in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М83) (2017),
https://hdl.handle.net/21.15107/rcub_machinery_5045 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Savićević, Sreten
AU  - Pantelić, Milorad P.
AU  - Milenović, Ivan Lj.
PY  - 2016
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2424
AB  - Determining a bucket wheel excavator (BWE)'s slewing superstructure weight and its center of gravity (COG) is of extreme importance not only in the design phase, but also after the completion of the erection process and during the operation of the machine. This paper presents a critical comparative analysis of the basic parameters of the static stability of a BWE 1600 superstructure, with the parameters being obtained by both analytical and experimental procedures. The analysis shows that a relatively small difference in superstructure mass, obtained by calculation, leads to a relatively large unfavorable shifting of its COG, necessitating a significant increase in counterweight mass for balancing. A procedure for superstructure 3D model mass correction is presented based on results obtained by weighing after the completion of the erection process. The developed model provides enough accuracy to determine the superstructure's COG in the entire domain of the bucket wheel boom inclination angle, and enables accurate load analysis of the superstructure's vital parts. The importance of this analysis is reinforced by the finding that the procedure prescribed by standard DIN 22261-2 gives results which are not on the side of safety, as shown by an example of strength analysis of a bucket wheel boom stays' end eyes.
PB  - Zhejiang Univ, Hangzhou
T2  - Journal of Zhejiang University-Science A
T1  - Basic parameters of the static stability, loads and strength of the vital parts of a bucket wheel excavator's slewing superstructure
EP  - 365
IS  - 5
SP  - 353
VL  - 17
DO  - 10.1631/jzus.A1500037
ER  - 

@article{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Savićević, Sreten and Pantelić, Milorad P. and Milenović, Ivan Lj.",
year = "2016",
abstract = "Determining a bucket wheel excavator (BWE)'s slewing superstructure weight and its center of gravity (COG) is of extreme importance not only in the design phase, but also after the completion of the erection process and during the operation of the machine. This paper presents a critical comparative analysis of the basic parameters of the static stability of a BWE 1600 superstructure, with the parameters being obtained by both analytical and experimental procedures. The analysis shows that a relatively small difference in superstructure mass, obtained by calculation, leads to a relatively large unfavorable shifting of its COG, necessitating a significant increase in counterweight mass for balancing. A procedure for superstructure 3D model mass correction is presented based on results obtained by weighing after the completion of the erection process. The developed model provides enough accuracy to determine the superstructure's COG in the entire domain of the bucket wheel boom inclination angle, and enables accurate load analysis of the superstructure's vital parts. The importance of this analysis is reinforced by the finding that the procedure prescribed by standard DIN 22261-2 gives results which are not on the side of safety, as shown by an example of strength analysis of a bucket wheel boom stays' end eyes.",
publisher = "Zhejiang Univ, Hangzhou",
journal = "Journal of Zhejiang University-Science A",
title = "Basic parameters of the static stability, loads and strength of the vital parts of a bucket wheel excavator's slewing superstructure",
pages = "365-353",
number = "5",
volume = "17",
doi = "10.1631/jzus.A1500037"
}

Bošnjak, S., Gnjatović, N., Savićević, S., Pantelić, M. P.,& Milenović, I. Lj.. (2016). Basic parameters of the static stability, loads and strength of the vital parts of a bucket wheel excavator's slewing superstructure. in Journal of Zhejiang University-Science A
Zhejiang Univ, Hangzhou., 17(5), 353-365.
https://doi.org/10.1631/jzus.A1500037

Bošnjak S, Gnjatović N, Savićević S, Pantelić MP, Milenović IL. Basic parameters of the static stability, loads and strength of the vital parts of a bucket wheel excavator's slewing superstructure. in Journal of Zhejiang University-Science A. 2016;17(5):353-365.
doi:10.1631/jzus.A1500037 .

Bošnjak, Srđan, Gnjatović, Nebojša, Savićević, Sreten, Pantelić, Milorad P., Milenović, Ivan Lj., "Basic parameters of the static stability, loads and strength of the vital parts of a bucket wheel excavator's slewing superstructure" in Journal of Zhejiang University-Science A, 17, no. 5 (2016):353-365,
https://doi.org/10.1631/jzus.A1500037 . .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Momčilović, Dejan B.
AU  - Milenović, Ivan Lj.
AU  - Gašić, Vlada
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2146
AB  - This paper presents an investigation of the accident which occurred during startup of the extending structure from the transport position. In order to clarify the causes of crack occurrence along almost the entire surface of the lever cross-section, the authors performed visual, experimental (chemical composition, tensile properties, microhardness) as well as metallographic examinations. Stress states in the critical zone are defined by applying the finite element method (FEM). Based on the investigation results it was concluded that the lever breakdown is predominantly caused by both the 'operating-in' defect (the malfunction of the limit switch) and the 'manufacturing-in' defect (poor weld quality). The investigation results presented in this paper are important because same or similar problems could arise in supporting structures of various types of transportation, construction and mining machines.
PB  - Elsevier Ltd
T2  - Case Studies in Engineering Failure Analysis
T1  - Failure analysis of the mobile elevating work platform
EP  - 87
SP  - 80
VL  - 3
DO  - 10.1016/j.csefa.2015.03.005
ER  - 

@article{
author = "Bošnjak, Srđan and Gnjatović, Nebojša and Momčilović, Dejan B. and Milenović, Ivan Lj. and Gašić, Vlada",
year = "2015",
abstract = "This paper presents an investigation of the accident which occurred during startup of the extending structure from the transport position. In order to clarify the causes of crack occurrence along almost the entire surface of the lever cross-section, the authors performed visual, experimental (chemical composition, tensile properties, microhardness) as well as metallographic examinations. Stress states in the critical zone are defined by applying the finite element method (FEM). Based on the investigation results it was concluded that the lever breakdown is predominantly caused by both the 'operating-in' defect (the malfunction of the limit switch) and the 'manufacturing-in' defect (poor weld quality). The investigation results presented in this paper are important because same or similar problems could arise in supporting structures of various types of transportation, construction and mining machines.",
publisher = "Elsevier Ltd",
journal = "Case Studies in Engineering Failure Analysis",
title = "Failure analysis of the mobile elevating work platform",
pages = "87-80",
volume = "3",
doi = "10.1016/j.csefa.2015.03.005"
}

Bošnjak, S., Gnjatović, N., Momčilović, D. B., Milenović, I. Lj.,& Gašić, V.. (2015). Failure analysis of the mobile elevating work platform. in Case Studies in Engineering Failure Analysis
Elsevier Ltd., 3, 80-87.
https://doi.org/10.1016/j.csefa.2015.03.005

Bošnjak S, Gnjatović N, Momčilović DB, Milenović IL, Gašić V. Failure analysis of the mobile elevating work platform. in Case Studies in Engineering Failure Analysis. 2015;3:80-87.
doi:10.1016/j.csefa.2015.03.005 .

Bošnjak, Srđan, Gnjatović, Nebojša, Momčilović, Dejan B., Milenović, Ivan Lj., Gašić, Vlada, "Failure analysis of the mobile elevating work platform" in Case Studies in Engineering Failure Analysis, 3 (2015):80-87,
https://doi.org/10.1016/j.csefa.2015.03.005 . .

TY  - CONF
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Milojević, Goran
AU  - Stefanović, Aleksandar Z.
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4922
AB  - Mounting and dismantling of large-scale mechanical systems is a complex engineering challenge due to several factors, such as structural diversity and size of handled structures, limited 
maneuvering options, and absence of related literature, to name the few, all of which make each problem unique. Numerous disasters throughout the history created a need for a safe approach to the problem of executing such procedures risk-free, while preserving the structural integrity and functionality of the structures. One of the most reliable methods is the application of unique below-the hook lifting devices and the goal of this paper is to present the benefits of their use via two examples. Case 1 deals with dismounting of dated constructions in a densely populated area, with limited structural data provided. Case 2 is focused on mounting of a large-scale roof structure in harsh boundary conditions, with limited maneuvering space. Results presented in this paper represent a contribution to the field of below-the hook lifting devices.
PB  - SaTCIP
C3  - Proceedings of the XXI International Conference MHCL’15
T1  - Specific Engineering Challenges During the Large-Scale Structures’ Mantling and Dismantling Procedures
EP  - 240
SP  - 235
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4922
ER  - 

@conference{
author = "Petković, Zoran D. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Milojević, Goran and Stefanović, Aleksandar Z.",
year = "2015",
abstract = "Mounting and dismantling of large-scale mechanical systems is a complex engineering challenge due to several factors, such as structural diversity and size of handled structures, limited 
maneuvering options, and absence of related literature, to name the few, all of which make each problem unique. Numerous disasters throughout the history created a need for a safe approach to the problem of executing such procedures risk-free, while preserving the structural integrity and functionality of the structures. One of the most reliable methods is the application of unique below-the hook lifting devices and the goal of this paper is to present the benefits of their use via two examples. Case 1 deals with dismounting of dated constructions in a densely populated area, with limited structural data provided. Case 2 is focused on mounting of a large-scale roof structure in harsh boundary conditions, with limited maneuvering space. Results presented in this paper represent a contribution to the field of below-the hook lifting devices.",
publisher = "SaTCIP",
journal = "Proceedings of the XXI International Conference MHCL’15",
title = "Specific Engineering Challenges During the Large-Scale Structures’ Mantling and Dismantling Procedures",
pages = "240-235",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4922"
}

Petković, Z. D., Gnjatović, N., Milenović, I. Lj., Milojević, G.,& Stefanović, A. Z.. (2015). Specific Engineering Challenges During the Large-Scale Structures’ Mantling and Dismantling Procedures. in Proceedings of the XXI International Conference MHCL’15
SaTCIP., 235-240.
https://hdl.handle.net/21.15107/rcub_machinery_4922

Petković ZD, Gnjatović N, Milenović IL, Milojević G, Stefanović AZ. Specific Engineering Challenges During the Large-Scale Structures’ Mantling and Dismantling Procedures. in Proceedings of the XXI International Conference MHCL’15. 2015;:235-240.
https://hdl.handle.net/21.15107/rcub_machinery_4922 .

Petković, Zoran D., Gnjatović, Nebojša, Milenović, Ivan Lj., Milojević, Goran, Stefanović, Aleksandar Z., "Specific Engineering Challenges During the Large-Scale Structures’ Mantling and Dismantling Procedures" in Proceedings of the XXI International Conference MHCL’15 (2015):235-240,
https://hdl.handle.net/21.15107/rcub_machinery_4922 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Savićević, Sreten
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Pantelić, Milorad P.
PY  - 2015
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/2224
AB  - A slope failure was the cause of a severe accident of bucket wheel excavator (BWE) Takraf SRs 1200. This paper is dedicated to the engineering challenges that accompanied the process of returning the BWE from its after accident state to the state of full exploitation readiness. After the accident, temporary stabilization of the superstructure was carried out as well as cutting off of severely damaged parts of the bucket wheel boom (BWB) with excavating device. Successful completion of the very delicate BWE rescue and balancing operation was followed by the reconstruction of the heavily damaged slewing platform. The integrity of the slewing platform structure was preserved by removing structural parts which were seriously damaged during long-term exploitation and breakdown, and installing the newly designed elements in critical zones. The redesign of the slewing platform structure produced favorable loads and stiffness distribution while eliminating geometrical stress concentrators. Comparative analyses of the stress states pointed out that the redesigned slewing platform structure meets the strength criterion, unlike the original structure. The redesign solution enabled reconstruction in field conditions. This way the time of the reconstruction realization was drastically cut and losses due to the downtime of the machine were reduced several times over. After completing the slewing platform reconstruction, the newly manufactured BWB structural elements as well as the newly manufactured bucket wheel with drive were installed i.e. a partial revitalization of the BWE was done and by that the BWE's life was essentially prolonged.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Disaster of the bucket wheel excavator caused by extreme environmental impact: Consequences, rescue and reconstruction
EP  - 374
SP  - 360
VL  - 56
DO  - 10.1016/j.engfailanal.2015.01.002
ER  - 

@article{
author = "Bošnjak, Srđan and Savićević, Sreten and Gnjatović, Nebojša and Milenović, Ivan Lj. and Pantelić, Milorad P.",
year = "2015",
abstract = "A slope failure was the cause of a severe accident of bucket wheel excavator (BWE) Takraf SRs 1200. This paper is dedicated to the engineering challenges that accompanied the process of returning the BWE from its after accident state to the state of full exploitation readiness. After the accident, temporary stabilization of the superstructure was carried out as well as cutting off of severely damaged parts of the bucket wheel boom (BWB) with excavating device. Successful completion of the very delicate BWE rescue and balancing operation was followed by the reconstruction of the heavily damaged slewing platform. The integrity of the slewing platform structure was preserved by removing structural parts which were seriously damaged during long-term exploitation and breakdown, and installing the newly designed elements in critical zones. The redesign of the slewing platform structure produced favorable loads and stiffness distribution while eliminating geometrical stress concentrators. Comparative analyses of the stress states pointed out that the redesigned slewing platform structure meets the strength criterion, unlike the original structure. The redesign solution enabled reconstruction in field conditions. This way the time of the reconstruction realization was drastically cut and losses due to the downtime of the machine were reduced several times over. After completing the slewing platform reconstruction, the newly manufactured BWB structural elements as well as the newly manufactured bucket wheel with drive were installed i.e. a partial revitalization of the BWE was done and by that the BWE's life was essentially prolonged.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Disaster of the bucket wheel excavator caused by extreme environmental impact: Consequences, rescue and reconstruction",
pages = "374-360",
volume = "56",
doi = "10.1016/j.engfailanal.2015.01.002"
}

Bošnjak, S., Savićević, S., Gnjatović, N., Milenović, I. Lj.,& Pantelić, M. P.. (2015). Disaster of the bucket wheel excavator caused by extreme environmental impact: Consequences, rescue and reconstruction. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 56, 360-374.
https://doi.org/10.1016/j.engfailanal.2015.01.002

Bošnjak S, Savićević S, Gnjatović N, Milenović IL, Pantelić MP. Disaster of the bucket wheel excavator caused by extreme environmental impact: Consequences, rescue and reconstruction. in Engineering Failure Analysis. 2015;56:360-374.
doi:10.1016/j.engfailanal.2015.01.002 .

Bošnjak, Srđan, Savićević, Sreten, Gnjatović, Nebojša, Milenović, Ivan Lj., Pantelić, Milorad P., "Disaster of the bucket wheel excavator caused by extreme environmental impact: Consequences, rescue and reconstruction" in Engineering Failure Analysis, 56 (2015):360-374,
https://doi.org/10.1016/j.engfailanal.2015.01.002 . .

TY  - CONF
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Milojević, Goran
AU  - Stefanović, Aleksandar Z.
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4916
AB  - Mounting of large-scale mechanical systems involves lifting and positioning of the so-called specific loads, namely structures of great dimensions and masses whose functionality and structural integrity should not be jeopardized during the realization of the erection procedures. Two examples of spatial truss roof construction mountings are presented in this paper as case 1, underlying the effect of unique lifting device usage on uniform load distribution on the structures being lifted. Case 2 deals with mounting of three tall vertical pressure vessels of different weights and heights with the same lifting gear and traverse specially designed to accomplish the aforementioned tasks. Case 3 is focused on the redesign of the existing traverse in order to fulfill the task of lifting and precise positioning of the bucket wheel excavator segment, a truss structure of a great span, weighing 90 t. Results presented in this paper represent a contribution in the field of below-the-hook lifting devices design, arising from the specificity of engineering problems dealing with mounting of large-scale structures.
PB  - SaTCIP
C3  - 14th International Conference "Research and Development in Mechanical Industry" RaDMI 2014
T1  - Design of unique below-the-hook lifting devices for specific loads
EP  - 51
SP  - 44
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4916
ER  - 

@conference{
author = "Petković, Zoran D. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Milojević, Goran and Stefanović, Aleksandar Z.",
year = "2014",
abstract = "Mounting of large-scale mechanical systems involves lifting and positioning of the so-called specific loads, namely structures of great dimensions and masses whose functionality and structural integrity should not be jeopardized during the realization of the erection procedures. Two examples of spatial truss roof construction mountings are presented in this paper as case 1, underlying the effect of unique lifting device usage on uniform load distribution on the structures being lifted. Case 2 deals with mounting of three tall vertical pressure vessels of different weights and heights with the same lifting gear and traverse specially designed to accomplish the aforementioned tasks. Case 3 is focused on the redesign of the existing traverse in order to fulfill the task of lifting and precise positioning of the bucket wheel excavator segment, a truss structure of a great span, weighing 90 t. Results presented in this paper represent a contribution in the field of below-the-hook lifting devices design, arising from the specificity of engineering problems dealing with mounting of large-scale structures.",
publisher = "SaTCIP",
journal = "14th International Conference "Research and Development in Mechanical Industry" RaDMI 2014",
title = "Design of unique below-the-hook lifting devices for specific loads",
pages = "51-44",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4916"
}

Petković, Z. D., Gnjatović, N., Milenović, I. Lj., Milojević, G.,& Stefanović, A. Z.. (2014). Design of unique below-the-hook lifting devices for specific loads. in 14th International Conference "Research and Development in Mechanical Industry" RaDMI 2014
SaTCIP., 44-51.
https://hdl.handle.net/21.15107/rcub_machinery_4916

Petković ZD, Gnjatović N, Milenović IL, Milojević G, Stefanović AZ. Design of unique below-the-hook lifting devices for specific loads. in 14th International Conference "Research and Development in Mechanical Industry" RaDMI 2014. 2014;:44-51.
https://hdl.handle.net/21.15107/rcub_machinery_4916 .

Petković, Zoran D., Gnjatović, Nebojša, Milenović, Ivan Lj., Milojević, Goran, Stefanović, Aleksandar Z., "Design of unique below-the-hook lifting devices for specific loads" in 14th International Conference "Research and Development in Mechanical Industry" RaDMI 2014 (2014):44-51,
https://hdl.handle.net/21.15107/rcub_machinery_4916 .

TY  - CONF
AU  - Gnjatović, Nebojša
AU  - Milojević, Goran
AU  - Milenović, Ivan Lj.
AU  - Stefanović, Aleksandar Z.
PY  - 2014
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4914
AB  - This paper describes the failure analysis results of undercarriage and superstructure vital 
subassemblies, which led to periodical stoppage and eventually total collapse of the bucket wheel excavator (BWE) SchRs 1760, once the machine with the highest theoretical capacity operating on the overburden excavation in open pit mine “Kolubara” - Serbia. It is conclusive that the main cause of two wheel bogie structural failure, described as case 1, is its insufficient strength during the action of lateral forces which are dominantly applied during the BWE curve travel. Case 2 analyses the support structure of portal tie-rods failure which was the consequence of superposition of the negative effects caused by inadequate shaping and dimensioning of the support assembly for given load conditions, as well as influences of defects of the metal weld structure. Both of the described failures are caused by the design-in faults.
PB  - SaTCIP
C3  - Proceedings of the The Eighth Triennial International Conference Heavy Machinery - HM 2014
T1  - ‘Design-in’ Faults - the Reason for Serious Drawbacks in High Capacity Bucket Wheel Excavator Exploitation
EP  - A.182
SP  - A.177
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4914
ER  - 

@conference{
author = "Gnjatović, Nebojša and Milojević, Goran and Milenović, Ivan Lj. and Stefanović, Aleksandar Z.",
year = "2014",
abstract = "This paper describes the failure analysis results of undercarriage and superstructure vital 
subassemblies, which led to periodical stoppage and eventually total collapse of the bucket wheel excavator (BWE) SchRs 1760, once the machine with the highest theoretical capacity operating on the overburden excavation in open pit mine “Kolubara” - Serbia. It is conclusive that the main cause of two wheel bogie structural failure, described as case 1, is its insufficient strength during the action of lateral forces which are dominantly applied during the BWE curve travel. Case 2 analyses the support structure of portal tie-rods failure which was the consequence of superposition of the negative effects caused by inadequate shaping and dimensioning of the support assembly for given load conditions, as well as influences of defects of the metal weld structure. Both of the described failures are caused by the design-in faults.",
publisher = "SaTCIP",
journal = "Proceedings of the The Eighth Triennial International Conference Heavy Machinery - HM 2014",
title = "‘Design-in’ Faults - the Reason for Serious Drawbacks in High Capacity Bucket Wheel Excavator Exploitation",
pages = "A.182-A.177",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4914"
}

Gnjatović, N., Milojević, G., Milenović, I. Lj.,& Stefanović, A. Z.. (2014). ‘Design-in’ Faults - the Reason for Serious Drawbacks in High Capacity Bucket Wheel Excavator Exploitation. in Proceedings of the The Eighth Triennial International Conference Heavy Machinery - HM 2014
SaTCIP., A.177-A.182.
https://hdl.handle.net/21.15107/rcub_machinery_4914

Gnjatović N, Milojević G, Milenović IL, Stefanović AZ. ‘Design-in’ Faults - the Reason for Serious Drawbacks in High Capacity Bucket Wheel Excavator Exploitation. in Proceedings of the The Eighth Triennial International Conference Heavy Machinery - HM 2014. 2014;:A.177-A.182.
https://hdl.handle.net/21.15107/rcub_machinery_4914 .

Gnjatović, Nebojša, Milojević, Goran, Milenović, Ivan Lj., Stefanović, Aleksandar Z., "‘Design-in’ Faults - the Reason for Serious Drawbacks in High Capacity Bucket Wheel Excavator Exploitation" in Proceedings of the The Eighth Triennial International Conference Heavy Machinery - HM 2014 (2014):A.177-A.182,
https://hdl.handle.net/21.15107/rcub_machinery_4914 .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Arsić, Miodrag
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4910
AB  - Design of the buckets of the bucket wheel excavators has to meet the set of the functional requirements imposed by the processes of: (a) soil cutting; (b) filling; (c) transportation of the grabbed soil; (d) emptying. Optimal conduct of each of these processes imposes requirements, which are often in mutual collision. Except functional requirements, bucket structure has to meet, naturally, rigidity as well as strength criterion. During exploitation in harsh working conditions, failures of buckets occur relatively frequently. There are two basic types of bucket failures: structural and technological. In this paper, two bucket structural failures as well as one technological bucket failure are presented. Investigations' results pointed out that structural failures are caused by 'design-in' as well 'manufacturing-in' defects. Technological failure of the bucket was also of the 'design-in' type. Besides that, the redesigned buckets' are presented. Exploitation after the reconstruction fully confirmed the validity of the presented reconstruction design.
PB  - Banja Luka : Faculty of Mechanical Engineering
C3  - Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology
T1  - Buckets of the bucket wheel excavators: failures and redesign
EP  - 248
SP  - 243
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4910
ER  - 

@conference{
author = "Bošnjak, Srđan and Petković, Zoran D. and Arsić, Miodrag and Gnjatović, Nebojša and Milenović, Ivan Lj.",
year = "2013",
abstract = "Design of the buckets of the bucket wheel excavators has to meet the set of the functional requirements imposed by the processes of: (a) soil cutting; (b) filling; (c) transportation of the grabbed soil; (d) emptying. Optimal conduct of each of these processes imposes requirements, which are often in mutual collision. Except functional requirements, bucket structure has to meet, naturally, rigidity as well as strength criterion. During exploitation in harsh working conditions, failures of buckets occur relatively frequently. There are two basic types of bucket failures: structural and technological. In this paper, two bucket structural failures as well as one technological bucket failure are presented. Investigations' results pointed out that structural failures are caused by 'design-in' as well 'manufacturing-in' defects. Technological failure of the bucket was also of the 'design-in' type. Besides that, the redesigned buckets' are presented. Exploitation after the reconstruction fully confirmed the validity of the presented reconstruction design.",
publisher = "Banja Luka : Faculty of Mechanical Engineering",
journal = "Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology",
title = "Buckets of the bucket wheel excavators: failures and redesign",
pages = "248-243",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4910"
}

Bošnjak, S., Petković, Z. D., Arsić, M., Gnjatović, N.,& Milenović, I. Lj.. (2013). Buckets of the bucket wheel excavators: failures and redesign. in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology
Banja Luka : Faculty of Mechanical Engineering., 243-248.
https://hdl.handle.net/21.15107/rcub_machinery_4910

Bošnjak S, Petković ZD, Arsić M, Gnjatović N, Milenović IL. Buckets of the bucket wheel excavators: failures and redesign. in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology. 2013;:243-248.
https://hdl.handle.net/21.15107/rcub_machinery_4910 .

Bošnjak, Srđan, Petković, Zoran D., Arsić, Miodrag, Gnjatović, Nebojša, Milenović, Ivan Lj., "Buckets of the bucket wheel excavators: failures and redesign" in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology (2013):243-248,
https://hdl.handle.net/21.15107/rcub_machinery_4910 .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Milojević, Goran
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4908
AB  - This paper presents the results of the study dedicated to the problem of the bucket wheel excavator equalizing system (ES) strength. Finite element analysis of two wheel (TWB), four wheel (FWB) and eight wheel (EWB) bogies were conducted in order to determine weak points in ES structure. Strength and carrying capacity of FWB and EWB structures might be jeopardized due to their insufficient strength under lateral forces acting during curve travel. Severe failure of similar TWB structure is also presented and certain paraleles were made.
PB  - SaTCIP
C3  - 13th International Conference "Research and Development in Mechanical Industry" RaDMI 2013
T1  - Strength analysis of bucket wheel excavator’s eight wheel equalizing system
EP  - 10
SP  - 1
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4908
ER  - 

@conference{
author = "Bošnjak, Srđan and Petković, Zoran D. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Milojević, Goran",
year = "2013",
abstract = "This paper presents the results of the study dedicated to the problem of the bucket wheel excavator equalizing system (ES) strength. Finite element analysis of two wheel (TWB), four wheel (FWB) and eight wheel (EWB) bogies were conducted in order to determine weak points in ES structure. Strength and carrying capacity of FWB and EWB structures might be jeopardized due to their insufficient strength under lateral forces acting during curve travel. Severe failure of similar TWB structure is also presented and certain paraleles were made.",
publisher = "SaTCIP",
journal = "13th International Conference "Research and Development in Mechanical Industry" RaDMI 2013",
title = "Strength analysis of bucket wheel excavator’s eight wheel equalizing system",
pages = "10-1",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4908"
}

Bošnjak, S., Petković, Z. D., Gnjatović, N., Milenović, I. Lj.,& Milojević, G.. (2013). Strength analysis of bucket wheel excavator’s eight wheel equalizing system. in 13th International Conference "Research and Development in Mechanical Industry" RaDMI 2013
SaTCIP., 1-10.
https://hdl.handle.net/21.15107/rcub_machinery_4908

Bošnjak S, Petković ZD, Gnjatović N, Milenović IL, Milojević G. Strength analysis of bucket wheel excavator’s eight wheel equalizing system. in 13th International Conference "Research and Development in Mechanical Industry" RaDMI 2013. 2013;:1-10.
https://hdl.handle.net/21.15107/rcub_machinery_4908 .

Bošnjak, Srđan, Petković, Zoran D., Gnjatović, Nebojša, Milenović, Ivan Lj., Milojević, Goran, "Strength analysis of bucket wheel excavator’s eight wheel equalizing system" in 13th International Conference "Research and Development in Mechanical Industry" RaDMI 2013 (2013):1-10,
https://hdl.handle.net/21.15107/rcub_machinery_4908 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Jerman, Boris
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1804
AB  - This paper presents the results of the study dedicated to the problem of the bucket wheel excavator two-wheel bogie (TWB) strength. Two variants of the TWB structure were analysed: the originally designed and the redesigned. Three calculation models for stress state identification were used for each of the variants. The first does not iclude the influence of the track wheel axle on the lateral loads distribution. The second model includes the mentioned influence while the third considers the track wheel axle as a structural part of the TWB. Validation of the FE models is done by FE simulation of the experiment carried out on an originally designed testing bench. The obtained results fully clarify the occurrence of cracks in the original TWB structure, as well as the considerable impact of the track wheel axles on the TWB structure stress state.
PB  - Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek
T2  - Tehnički vjesnik
T1  - Impact of the track wheel axles on the strength of the bucket wheel excavator two-wheel bogie
EP  - 810
IS  - 5
SP  - 803
VL  - 20
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1804
ER  - 

@article{
author = "Bošnjak, Srđan and Petković, Zoran D. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Jerman, Boris",
year = "2013",
abstract = "This paper presents the results of the study dedicated to the problem of the bucket wheel excavator two-wheel bogie (TWB) strength. Two variants of the TWB structure were analysed: the originally designed and the redesigned. Three calculation models for stress state identification were used for each of the variants. The first does not iclude the influence of the track wheel axle on the lateral loads distribution. The second model includes the mentioned influence while the third considers the track wheel axle as a structural part of the TWB. Validation of the FE models is done by FE simulation of the experiment carried out on an originally designed testing bench. The obtained results fully clarify the occurrence of cracks in the original TWB structure, as well as the considerable impact of the track wheel axles on the TWB structure stress state.",
publisher = "Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek",
journal = "Tehnički vjesnik",
title = "Impact of the track wheel axles on the strength of the bucket wheel excavator two-wheel bogie",
pages = "810-803",
number = "5",
volume = "20",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1804"
}

Bošnjak, S., Petković, Z. D., Gnjatović, N., Milenović, I. Lj.,& Jerman, B.. (2013). Impact of the track wheel axles on the strength of the bucket wheel excavator two-wheel bogie. in Tehnički vjesnik
Faculty of Mechanical Engineering in Slavonski Brod, Faculty of Electrical Engineering in Osijek, Faculty of Civil Engineering in Osijek., 20(5), 803-810.
https://hdl.handle.net/21.15107/rcub_machinery_1804

Bošnjak S, Petković ZD, Gnjatović N, Milenović IL, Jerman B. Impact of the track wheel axles on the strength of the bucket wheel excavator two-wheel bogie. in Tehnički vjesnik. 2013;20(5):803-810.
https://hdl.handle.net/21.15107/rcub_machinery_1804 .

Bošnjak, Srđan, Petković, Zoran D., Gnjatović, Nebojša, Milenović, Ivan Lj., Jerman, Boris, "Impact of the track wheel axles on the strength of the bucket wheel excavator two-wheel bogie" in Tehnički vjesnik, 20, no. 5 (2013):803-810,
https://hdl.handle.net/21.15107/rcub_machinery_1804 .