Reliability Design of the Hinge Kit System (HKS)in a Commercial Refrigerator Subjected to Repetitive Impact Loading

Based on field data and a tailored set of accelerated life tests, the hinge kit system (HKS) of a closing door in a refrigerator was redesigned to improve its reliability. Using a force and moment balance analysis, the mechanical impact loads of HKS were calculated in closing the refrigerator door. At first ALT the HKS failure happened in the fracture of the kit housing, and oil damper was leaking in breaking up HKS. The failure modes and mechanisms found in 1st ALT were similar to those of the failed samples obtained in the field. The missing design parameters of HKS included the corner rounding and rib of the housing hinge kit, the oil sealing way ofthe oil damper, and the material of the cover housing. Based on second ALTs, the fracturing occurred in the cover housing. The missing design parameter of the cover housing in HKS was the plastics material. After two rounds of parametric ALT with corrective action plans, reliability of the new HKS is guaranteed to be over B1 life 10 years with a yearly failure rate of 0.1%.