Tehnički vjesnik, Vol. 18 No. 4, 2011.
Izvorni znanstveni članak
Model for fatigue lifetime prediction of torsion bars subjected to plastic presetting
Vinko Močilnik
; ERD d.o.o., Engineering, Design & Development, Črneče 186, 2370 Dravograd, Slovenia
Nenad Gubeljak
orcid.org/0000-0002-3276-8431
; University of Maribor, Faculty of Mechanical Engineering, Smetanova ul. 17, 2000 Maribor, Slovenia
Jožef Predan
; University of Maribor, Faculty of Mechanical Engineering, Smetanova ul. 17, 2000 Maribor, Slovenia
Sažetak
The torsion presetting of a spring-bar is a common technique for extending the elastic twist-angle and increasing torque, but it reduces fatigue lifetime. Spring-bars are used as shock absorbers in caterpillar machines. Spring-bars, made from high strength fine-grain steel, grade VCN, provide a high level of absorbed energy. Any slight change in the presetting procedure has a strong influence on fatigue-lifetime. Within the same loading range, springs can exhibit low-cyclic or high-cyclic fatigue behavior regarding different presetting levels. A model for fatigue-lifetime and shear-stress levels is proposed on the basis of performed tests. Considering prescribed fatigue tests, it is possible to optimize a spring bar's geometry, in order to survive the required number of cycles.
Ključne riječi
presetting; torsion; spring-bars; fatigue; lifetime; cyclic fatigue; torque; spring steel
Hrčak ID:
75400
URI
Datum izdavanja:
27.12.2011.
Posjeta: 6.044 *