Structured Methods to Increase the Lifetime of Mechanical Products Such as Gear by Parametric Accelerated Life Testing for Power System

Abstract

This investigation explains the implementation of parametric accelerated life testing (ALT) as an algorithm to recognize design imperfection and rectify it. It covers (1) a module BX life with an ALT plan, (2) design for fatigue, (3) ALTs with alterations, and (4) discernment if the final design(s) obtains the targeted BX lifetime. A (generalized) life–stress formulation is recommended. As a case study, an ice-maker was utilized. The gear teeth made of cast iron was fracturing in a refrigerator. To reproduce the field failure and rectify it, a parametric ALT was carried out. At the first ALT, the gear teeth made of cast iron partly cracked under severe cold conditions in the freezer. It was modified by changing the material from cast iron to a sinter-hardened powder metallurgy nickel steel. At the second ALT, the authors discovered the fractured helix made of polycarbonates (PC). As a modification, strengthened rib on the front and side of the helix the thickness was attached. At the third ALT, there was no concern, and the life of the auger motor was manifested to have a B1 life 10 years.