The selective method of calculation because of the profitability is successfully applied several centuries. However when calculating non-failure operation in case of fatigue failures (often sudden) when there is a considerable sedate communication of m=10-15 for the supermulti-cycle field of loading between durability (hardness, an endurance limit) and the operating tension, decrease in the minimum resource of details will make 10-100 and more times. It turns out because of an unaccounted main part of population. In our example of 104-50=9950 pieces of such details, i.e. their potential refusals. Therefore for this case a selective method – the intermediate stage of calculations.
Keywords: selection, fatigue resource, population of final volume, sedate communication
Researches of hardness of various steel grades for the purpose of determination of density of their distribution and distribution of extremes of selections are conducted. Results of the received researches are used for definition of a resource of details with use of a graphic method of transition from selection to set.
Keywords: selection, fatigue resource, population of final volume