Model of selective assembly process of rod-piston group parts of internal combustion engines

Abstract

Functioning of conrod-piston group of internal combustion engine is considered. It is shown that the main method of assembly of this unit is selective assembly, which provides the required accuracy of parts joints. The scheme of the assembly set-making is given, a mathematical model of the process of its selective assembly with the selected strategy is built. As a strategy, a single-variant set-making is proposed, in which the assembly is carried out from the groups of the same numbers. The constructed model allows to determine the process indicators, in particular, the probability of obtaining suitable assembled sets, the probability of incomplete elements, forming work in progress and preliminary scrappage. The task of optimal assembly of rod-piston group at specified values of extended tolerances and arrangement of tolerance intervals by rational selection of boundaries of selective groups is set. The solution of this task is given.