Структурная модель и расчет показателей надежности сборных торцовых фрез

Abstract

The cutter body and the insert holding mechanism are highly reliable elements that have a probability of failure-free operation close to unity in the period of time before the tool stops. The reliability of the cutter is assessed by the reliability of its inserts (cutting part), which often fail due to breakages and chipping. The assembled face milling cutter has a reliability model of a parallel-serial type with a constant loaded reserve caused by the constructive redundancy of the tool. The cutter performance criterion is the load capacity of the plate (tooth), determined by the "breaking" feed. Models of reliability and examples of evaluating the reliability of face mills with the number of teeth z = 6 at various tool feeds are presented. The calculation of the reliability of the tool was made using a logical- probabilistic method. It was found that there is an extreme (optimal) feed, which determines the specified level of tool reliability as a whole, and the change in feed has a nonlinear effect on the level of reliability of face milling.