Advanced determination of safety factor of fatique strength of coiled springs

• Autorzy: Aryassov G. , Petritshenko A.
• Języki publikacji: EN

Abstrakty

EN

Coiled compression springs are widely used in suspension systems of vehicles, light weight trailers, trains etc and their task is to minimize dynamic loading effect to vehicles body or frame in different road condition over many years. In these systems, springs are exposed to large number of cycles of loading and determination of their durability and reliability quantities is important. Consequently, to increase the reliability of these systems, a more accurate determination of the values of the endurance limits of springs is necessary. Usually, in many strength problems, the major components of stress are static, with less accurately alternating stresses superposed. Most failures of springs are originated with stress of alternating type. The solution of problem is accomplished due to acting shear and axial stresses in plane of cross-section of spring wire. By existing theory, when springs are loaded by non-steady loading, then to consider of unlimited number of combinations of amplitude and mean stresses, the line of failure of the material must be used. Since experimental data for the line of failure of material are usually not at hand, it is customary to make a conservative approximation, that it is a straight line. However, use this straight line may give considerable mistakes on determination of the limit range stresses. To avoid fore aft mentioned mistakes, the method of approximation of the failure curve line by the line with the properly chosen parameters for the coiled compression and tension springs is proposed in this paper. Theory to use proper parameters in approximation of failure curve and calculation example with results is given as well.

Słowa kluczowe

EN

coiled springs; fatigue failure; safety factor; alternate stress; endurance limit stress

• Wydawca: Wydawnictwo Wrocławskiej Rady FSNT NOT
• Czasopismo: Journal of Machine Engineering
• Rocznik: 2008
• Tom: Vol. 8, No. 4
• Strony: 111--121
• Opis fizyczny: Bibliogr. 4 poz., rys.

Twórcy

autor

Aryassov G.

• Tallinn University of Technology, Department of Mechatronics

autor

Petritshenko A.

• Tallinn University of Technology, Department of Mechatronics

Bibliografia

• [1] FUCHS H., STEPHENS R., Metal Fatigue in Engineering, New York, J. Wiley, 1980.
• [2] RABINOVICH, I., Calculation of structures to load changing in time by random periodic law, Moscow, Machinbuilding, 1960.
• [3] SERENSEN S., KOGAEV V., SCHNEIDEROVITCH V., The Load Capacity and Strength Calculation of Machine Parts, Moscow, Machinbuilding, 1975.
• [4] TIMOSHENKO S., YOUNG D., Elements of strength of materials, Princeton, D. van Nostrand Company, 1962.