Bulletin of
Vitebsk State
Technological
University

Abstract

Purpose of the article is to present the positions of calculation-experimental method for determination of longevity of details on the stage of planning on the criterion of fatigue strength. A calculation is executed in the probabilistic raising on the basis of information about the spectrum of loadings and these operating supervisions as it applies to the knitting needles of automatic half-hose machine. Recommendation for the calculation of cycles and sizes of loadings for needles, providing integrity of calculation from the dynamic model of shock co-operation of needles for determination of longevity are offered. Numeral – analytical method for determination of loading as polynomial dependence as function of casual arguments is used. Non-trivial approach is recommended for getting the histogram of relative frequencies of appearance of values of loadings which do not correspond to the normal law of distribution. Dependence of limit of the limited fatigue of needles is got on their cyclic longevity in a probabilistic form.

The results of calculation allow to analyze the efficiency of structural decisions of knitting mechanisms of automats on the level of tireless longevity
of needles to the set number of cycles of loadings on the stage of planning.

Analysis of influence of dynamic loadings on longevity of knittings needles of automatic half-hose machine