Evaluation of effect of surface quality of machined rail way wheels on fatigue strength

Rostislav Fajkoš,

Radim Zima

Abstrakt

Railway transport capacities all over the world have been growing, a phenomenon which is accompanied by the requirement to increase axle loads of freight rolling stock. Apart from new wheel designs for higher axle loads, the requirements of their safety and reliability have also been growing, since these wheels are often used in extreme climactic conditions. Cruising speeds of passenger trains been increasing, which likewise brings more stringent requirements concerning the quality and safety of the supplied railway wheels. This paper describes methods of evaluating fatigue strength of railway wheel webs and methods of evaluating the quality of machined railway wheel webs. Results of fatigue tests performed on wheels machined in a standard way are compared with wheels which have been treated by shot peening, a treatment frequently used to increase the fatigue strength of wheel webs of the railway wheelset.

Słowa kluczowe: railway wheels, shot peening, fatigue strength, surface layer
References

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