TY  - CONF
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Mihajlović, Vaso M.
AU  - Milojević, Goran
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4912
AB  - The extremely heavy duty conditions of the Surface Mining Machines (SMM) provide fertile ground for the occurrence of the various types of failures in their travelling mechanisms and belonging substructures. Although failures of the SMM travelling mechanisms occur infrequently, they may lead to very serious or even disastrous consequences. Even in cases when consequences are not catastrophic they cause direct costs, as well as indirect costs due to the downtime that substantially diminishes the effects of SMM exploitation. Furthermore, replacement of damaged parts is executed on site, often in hard working conditions that essentially prolong the downtime of the complete surface mining system. This paper discusses the causes of the failures in the vital parts of the crawler travel gear of the bucket wheel excavators and spreaders: chain links, track wheels, two-wheel bogies and undercarriage. Based on the results of the analytical–numerical–experimental analyses, it was concluded
that: (a) chain links' failures are caused by 'manufacturing-in' defects; (b) track wheels'
failures are caused by 'design-in' and ' manufacturing-in' defects; (c) failures of the twowheel bogies and undercarriage are caused by 'design-in' defects. Besides that, the redesigned structures of the two-wheel bogies and undercarriage are presented. The validity of the presented reconstruction designs are unquestionably confirmed by their failure less exploitation after the reconstruction. Finally, the obtained results are important because the same problems could arise in the crawler travelling mechanisms of wide class of earthmoving and material handling machines.
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  - Strength problems of the travelling mechanisms of the open pit machines
EP  - 254
SP  - 249
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4912
ER  - 

@conference{
author = "Bošnjak, Srđan and Petković, Zoran D. and Gnjatović, Nebojša and Mihajlović, Vaso M. and Milojević, Goran",
year = "2013",
abstract = "The extremely heavy duty conditions of the Surface Mining Machines (SMM) provide fertile ground for the occurrence of the various types of failures in their travelling mechanisms and belonging substructures. Although failures of the SMM travelling mechanisms occur infrequently, they may lead to very serious or even disastrous consequences. Even in cases when consequences are not catastrophic they cause direct costs, as well as indirect costs due to the downtime that substantially diminishes the effects of SMM exploitation. Furthermore, replacement of damaged parts is executed on site, often in hard working conditions that essentially prolong the downtime of the complete surface mining system. This paper discusses the causes of the failures in the vital parts of the crawler travel gear of the bucket wheel excavators and spreaders: chain links, track wheels, two-wheel bogies and undercarriage. Based on the results of the analytical–numerical–experimental analyses, it was concluded
that: (a) chain links' failures are caused by 'manufacturing-in' defects; (b) track wheels'
failures are caused by 'design-in' and ' manufacturing-in' defects; (c) failures of the twowheel bogies and undercarriage are caused by 'design-in' defects. Besides that, the redesigned structures of the two-wheel bogies and undercarriage are presented. The validity of the presented reconstruction designs are unquestionably confirmed by their failure less exploitation after the reconstruction. Finally, the obtained results are important because the same problems could arise in the crawler travelling mechanisms of wide class of earthmoving and material handling machines.",
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 = "Strength problems of the travelling mechanisms of the open pit machines",
pages = "254-249",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4912"
}

Bošnjak, S., Petković, Z. D., Gnjatović, N., Mihajlović, V. M.,& Milojević, G.. (2013). Strength problems of the travelling mechanisms of the open pit machines. in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology
Banja Luka : Faculty of Mechanical Engineering., 249-254.
https://hdl.handle.net/21.15107/rcub_machinery_4912

Bošnjak S, Petković ZD, Gnjatović N, Mihajlović VM, Milojević G. Strength problems of the travelling mechanisms of the open pit machines. in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology. 2013;:249-254.
https://hdl.handle.net/21.15107/rcub_machinery_4912 .

Bošnjak, Srđan, Petković, Zoran D., Gnjatović, Nebojša, Mihajlović, Vaso M., Milojević, Goran, "Strength problems of the travelling mechanisms of the open pit machines" in Proceedings of the 11th International conference on accomplishments in Electrical and Mechanical Engineering and Information Technology (2013):249-254,
https://hdl.handle.net/21.15107/rcub_machinery_4912 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Atanasovska, Ivana
AU  - Milojević, Goran
AU  - Mihajlović, Vaso M.
PY  - 2013
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1724
AB  - The supporting truss of the counterweight boom is a vital part of the bucket chain excavator's (BCE) superstructure. The occurrence and propagation of cracks in the supporting truss columns' heads may lead to BCE collapse. The goals of the study presented in this paper were to: (a) diagnose the cause of cracks occurrence; (b) define the reconstruction design of the supporting truss columns and (c) validate the reconstructed structure by numerical-experimental analysis. In order to clarify the causes of cracks occurrence, experimental investigations were performed with the purpose of defining the chemical composition, tensile properties, impact toughness and macrohardness of the columns' material. Metallographic examinations were also conducted. Based on the results of finite elements analyses (FEA) and experimental analyses it can be concluded that cracks are caused by the 'design-in' defects. The redesign solution enabled repair and reconstruction in field conditions, without previously dismantling any substructure of the BCE superstructure. Thereby the time required for performing reconstruction is shortened and indirect costs due to the BCE downtime are considerably diminished. Both the experimental analysis of the stress state of the reconstructed columns in regular working conditions and the failure-free exploitation have confirmed the validity of the reconstruction design, while the BCE excavated approximately 8.5 x 10(6) t of coal and 1.8 x 10(6) m(3) of overburden after the reconstruction.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Bucket chain excavator: Failure analysis and redesign of the counterweight boom supporting truss columns
EP  - 333
SP  - 322
VL  - 32
DO  - 10.1016/j.engfailanal.2013.04.012
ER  - 

@article{
author = "Bošnjak, Srđan and Petković, Zoran D. and Atanasovska, Ivana and Milojević, Goran and Mihajlović, Vaso M.",
year = "2013",
abstract = "The supporting truss of the counterweight boom is a vital part of the bucket chain excavator's (BCE) superstructure. The occurrence and propagation of cracks in the supporting truss columns' heads may lead to BCE collapse. The goals of the study presented in this paper were to: (a) diagnose the cause of cracks occurrence; (b) define the reconstruction design of the supporting truss columns and (c) validate the reconstructed structure by numerical-experimental analysis. In order to clarify the causes of cracks occurrence, experimental investigations were performed with the purpose of defining the chemical composition, tensile properties, impact toughness and macrohardness of the columns' material. Metallographic examinations were also conducted. Based on the results of finite elements analyses (FEA) and experimental analyses it can be concluded that cracks are caused by the 'design-in' defects. The redesign solution enabled repair and reconstruction in field conditions, without previously dismantling any substructure of the BCE superstructure. Thereby the time required for performing reconstruction is shortened and indirect costs due to the BCE downtime are considerably diminished. Both the experimental analysis of the stress state of the reconstructed columns in regular working conditions and the failure-free exploitation have confirmed the validity of the reconstruction design, while the BCE excavated approximately 8.5 x 10(6) t of coal and 1.8 x 10(6) m(3) of overburden after the reconstruction.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Bucket chain excavator: Failure analysis and redesign of the counterweight boom supporting truss columns",
pages = "333-322",
volume = "32",
doi = "10.1016/j.engfailanal.2013.04.012"
}

Bošnjak, S., Petković, Z. D., Atanasovska, I., Milojević, G.,& Mihajlović, V. M.. (2013). Bucket chain excavator: Failure analysis and redesign of the counterweight boom supporting truss columns. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 32, 322-333.
https://doi.org/10.1016/j.engfailanal.2013.04.012

Bošnjak S, Petković ZD, Atanasovska I, Milojević G, Mihajlović VM. Bucket chain excavator: Failure analysis and redesign of the counterweight boom supporting truss columns. in Engineering Failure Analysis. 2013;32:322-333.
doi:10.1016/j.engfailanal.2013.04.012 .

Bošnjak, Srđan, Petković, Zoran D., Atanasovska, Ivana, Milojević, Goran, Mihajlović, Vaso M., "Bucket chain excavator: Failure analysis and redesign of the counterweight boom supporting truss columns" in Engineering Failure Analysis, 32 (2013):322-333,
https://doi.org/10.1016/j.engfailanal.2013.04.012 . .

TY  - CONF
AU  - Petković, Zoran D.
AU  - Bošnjak, Srđan
AU  - Gnjatović, Nebojša
AU  - Mihajlović, Vaso M.
AU  - Milojević, Goran
PY  - 2012
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4905
AB  - Bucket wheel excavator SchRs 350/5x12 is one of the oldest mining
machines still operating in open pit mines in Serbia. Bucket wheel drive
gearbox of classical type had to be substituted with planetary one, in order
to eliminate the original design drawbacks. Integration of new bucket
wheel drive solution requires a subtle redesign of the bucket wheel boom.
Calculation verification of bucket wheel boom structure is realized on
basis of comparative stress analysis of the original and redesigned
construction. Sixteen different load cases were analyzed. Results of finite
element analysis are presented in this paper. Presented redesign solution
makes the installation of new bucket wheel drive possible, maintenance
process easier and prolongs the service life of the machine.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proceedings of the XX International Conference MHCL’12
T1  - Redesign of the BWE SchRs 350 bucket wheel boom
EP  - 154
SP  - 149
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4905
ER  - 

@conference{
author = "Petković, Zoran D. and Bošnjak, Srđan and Gnjatović, Nebojša and Mihajlović, Vaso M. and Milojević, Goran",
year = "2012",
abstract = "Bucket wheel excavator SchRs 350/5x12 is one of the oldest mining
machines still operating in open pit mines in Serbia. Bucket wheel drive
gearbox of classical type had to be substituted with planetary one, in order
to eliminate the original design drawbacks. Integration of new bucket
wheel drive solution requires a subtle redesign of the bucket wheel boom.
Calculation verification of bucket wheel boom structure is realized on
basis of comparative stress analysis of the original and redesigned
construction. Sixteen different load cases were analyzed. Results of finite
element analysis are presented in this paper. Presented redesign solution
makes the installation of new bucket wheel drive possible, maintenance
process easier and prolongs the service life of the machine.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proceedings of the XX International Conference MHCL’12",
title = "Redesign of the BWE SchRs 350 bucket wheel boom",
pages = "154-149",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4905"
}

Petković, Z. D., Bošnjak, S., Gnjatović, N., Mihajlović, V. M.,& Milojević, G.. (2012). Redesign of the BWE SchRs 350 bucket wheel boom. in Proceedings of the XX International Conference MHCL’12
University of Belgrade, Faculty of Mechanical Engineering., 149-154.
https://hdl.handle.net/21.15107/rcub_machinery_4905

Petković ZD, Bošnjak S, Gnjatović N, Mihajlović VM, Milojević G. Redesign of the BWE SchRs 350 bucket wheel boom. in Proceedings of the XX International Conference MHCL’12. 2012;:149-154.
https://hdl.handle.net/21.15107/rcub_machinery_4905 .

Petković, Zoran D., Bošnjak, Srđan, Gnjatović, Nebojša, Mihajlović, Vaso M., Milojević, Goran, "Redesign of the BWE SchRs 350 bucket wheel boom" in Proceedings of the XX International Conference MHCL’12 (2012):149-154,
https://hdl.handle.net/21.15107/rcub_machinery_4905 .

TY  - GEN
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Gnjatović, Nebojša
AU  - Milenović, Ivan Lj.
AU  - Mihajlović, Vaso M.
AU  - Milojević, Goran
PY  - 2012
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5271
AB  - Роторни багер SRs 1200x24/4x4+VR (G ‐ 3) био је ангажован на ископу јаловине на „Пољу Д“ РБ Колубара. Дана 06.11. 2012. године дошло је до тешке хаварије машине изазване обрушавањем чела етаже.Суштина техничког решења јесте да се редизајном структуре која је претрпела тешко хаваријско оштећење обезбеди повољнија дистрибуција оптерећења, елиминишу геометријски концентратори напона и оствари повољнија дистрибуција крутости унутар структуре. Осим тога, оштра ограничења током развоја редизајниране структуре представљали су захтеви да се реконструкција обави у теренским условима, без демонтаже подсистема носеће конструкције. Тиме је време извођења реконструкције драстично скраћено и вишеструко су смањени губици изазвани застојем машине, односно, целокупног БТО система.
PB  - University of Belgrade, Faculty of Mechanical Engineering
T2  - ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М84)
T1  - Редизајн обртне платформе роторног багера SRs 1200
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5271
ER  - 

@misc{
author = "Bošnjak, Srđan and Petković, Zoran D. and Gnjatović, Nebojša and Milenović, Ivan Lj. and Mihajlović, Vaso M. and Milojević, Goran",
year = "2012",
abstract = "Роторни багер SRs 1200x24/4x4+VR (G ‐ 3) био је ангажован на ископу јаловине на „Пољу Д“ РБ Колубара. Дана 06.11. 2012. године дошло је до тешке хаварије машине изазване обрушавањем чела етаже.Суштина техничког решења јесте да се редизајном структуре која је претрпела тешко хаваријско оштећење обезбеди повољнија дистрибуција оптерећења, елиминишу геометријски концентратори напона и оствари повољнија дистрибуција крутости унутар структуре. Осим тога, оштра ограничења током развоја редизајниране структуре представљали су захтеви да се реконструкција обави у теренским условима, без демонтаже подсистема носеће конструкције. Тиме је време извођења реконструкције драстично скраћено и вишеструко су смањени губици изазвани застојем машине, односно, целокупног БТО система.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М84)",
title = "Редизајн обртне платформе роторног багера SRs 1200",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5271"
}

Bošnjak, S., Petković, Z. D., Gnjatović, N., Milenović, I. Lj., Mihajlović, V. M.,& Milojević, G.. (2012). Редизајн обртне платформе роторног багера SRs 1200. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М84)
University of Belgrade, Faculty of Mechanical Engineering..
https://hdl.handle.net/21.15107/rcub_machinery_5271

Bošnjak S, Petković ZD, Gnjatović N, Milenović IL, Mihajlović VM, Milojević G. Редизајн обртне платформе роторног багера SRs 1200. in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М84). 2012;.
https://hdl.handle.net/21.15107/rcub_machinery_5271 .

Bošnjak, Srđan, Petković, Zoran D., Gnjatović, Nebojša, Milenović, Ivan Lj., Mihajlović, Vaso M., Milojević, Goran, "Редизајн обртне платформе роторног багера SRs 1200" in ТЕХНИЧКО РЕШЕЊЕ (КАТЕГОРИЈА М84) (2012),
https://hdl.handle.net/21.15107/rcub_machinery_5271 .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Milojević, Goran
AU  - Mihajlović, Vaso M.
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5958
AB  - High capacities and key roles in the technological processes cause the extremely high financial losses in the case of high performance machines failures. This paper presents case studies of bucket wheel excavators, stackers and bucket chain reclaimers failures caused by design – in faults. Besides that, paper gives a redesign solutions which are developed by University of Belgrade – Faculty of Mechanical Engineering.
PB  - Faculty of Mechanical Engineering, Kraljevo
C3  - Proceedings of 7th International Triennial Conference Heavy Machinery „HM 2011“
T1  - The Design – in Faults as a Causes of the High Performance Machines Failures
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5958
ER  - 

@conference{
author = "Bošnjak, Srđan and Petković, Zoran D. and Milojević, Goran and Mihajlović, Vaso M.",
year = "2011",
abstract = "High capacities and key roles in the technological processes cause the extremely high financial losses in the case of high performance machines failures. This paper presents case studies of bucket wheel excavators, stackers and bucket chain reclaimers failures caused by design – in faults. Besides that, paper gives a redesign solutions which are developed by University of Belgrade – Faculty of Mechanical Engineering.",
publisher = "Faculty of Mechanical Engineering, Kraljevo",
journal = "Proceedings of 7th International Triennial Conference Heavy Machinery „HM 2011“",
title = "The Design – in Faults as a Causes of the High Performance Machines Failures",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5958"
}

Bošnjak, S., Petković, Z. D., Milojević, G.,& Mihajlović, V. M.. (2011). The Design – in Faults as a Causes of the High Performance Machines Failures. in Proceedings of 7th International Triennial Conference Heavy Machinery „HM 2011“
Faculty of Mechanical Engineering, Kraljevo..
https://hdl.handle.net/21.15107/rcub_machinery_5958

Bošnjak S, Petković ZD, Milojević G, Mihajlović VM. The Design – in Faults as a Causes of the High Performance Machines Failures. in Proceedings of 7th International Triennial Conference Heavy Machinery „HM 2011“. 2011;.
https://hdl.handle.net/21.15107/rcub_machinery_5958 .

Bošnjak, Srđan, Petković, Zoran D., Milojević, Goran, Mihajlović, Vaso M., "The Design – in Faults as a Causes of the High Performance Machines Failures" in Proceedings of 7th International Triennial Conference Heavy Machinery „HM 2011“ (2011),
https://hdl.handle.net/21.15107/rcub_machinery_5958 .

TY  - CONF
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Mihajlović, Vaso M.
AU  - Milojević, Goran
AU  - Milenović, Ivan Lj.
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5954
AB  - One way of solving the improperly parked cars problem is their towing by means of a special vehicle. Hanging the car and putting it onto that vehicle is realized by a special lifting device. This paper presents some design details of the 5 t lifting capacity device.
PB  - SaTCIP (Scientific and Technical Center for Intellectual Property) Ltd.
C3  - Proceedings of 11th International Conference of Research and Development in Mechanical Industry „RaDMI 2011“
T1  - CAD of the special car lifting device
VL  - 1
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5954
ER  - 

@conference{
author = "Bošnjak, Srđan and Petković, Zoran D. and Mihajlović, Vaso M. and Milojević, Goran and Milenović, Ivan Lj.",
year = "2011",
abstract = "One way of solving the improperly parked cars problem is their towing by means of a special vehicle. Hanging the car and putting it onto that vehicle is realized by a special lifting device. This paper presents some design details of the 5 t lifting capacity device.",
publisher = "SaTCIP (Scientific and Technical Center for Intellectual Property) Ltd.",
journal = "Proceedings of 11th International Conference of Research and Development in Mechanical Industry „RaDMI 2011“",
title = "CAD of the special car lifting device",
volume = "1",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5954"
}

Bošnjak, S., Petković, Z. D., Mihajlović, V. M., Milojević, G.,& Milenović, I. Lj.. (2011). CAD of the special car lifting device. in Proceedings of 11th International Conference of Research and Development in Mechanical Industry „RaDMI 2011“
SaTCIP (Scientific and Technical Center for Intellectual Property) Ltd.., 1.
https://hdl.handle.net/21.15107/rcub_machinery_5954

Bošnjak S, Petković ZD, Mihajlović VM, Milojević G, Milenović IL. CAD of the special car lifting device. in Proceedings of 11th International Conference of Research and Development in Mechanical Industry „RaDMI 2011“. 2011;1.
https://hdl.handle.net/21.15107/rcub_machinery_5954 .

Bošnjak, Srđan, Petković, Zoran D., Mihajlović, Vaso M., Milojević, Goran, Milenović, Ivan Lj., "CAD of the special car lifting device" in Proceedings of 11th International Conference of Research and Development in Mechanical Industry „RaDMI 2011“, 1 (2011),
https://hdl.handle.net/21.15107/rcub_machinery_5954 .