To improve the reliability of compressor subjected to repetitive pressure loading, a reliability methodology for parametric accelerated life testing (ALT) was suggested. It consisted of a parametric ALT plan, a generalized lifestress failure model with a new effort concept, an acceleration factor, and a sample size equation. Based on failure analysis, this parametric ALT should help an engineer uncover the design parameters affecting reliability during the design process of a compressor. As a test case, a compressor with a newly designed crankshaft subjected to repetitive pressure loading was studied. Using a mass and energy balance analysis, the pressure loads of compressor were analyzed. In the first ALT and field, the failure mode was compressor locking due to crankshaft wear. The missing design parameter of the crankshaft was the improper lubrication structure in the crankshaft. As a corrective action plan, the crankshafts were redesigned. In the second ALT, wear in the compressor crankshaft occurred. The minimum clearance between the crankshaft and thrust washer was then modified. After another parametric ALT with corrective action plans, the reliability of the newly designed compressor was expected to have a life of 10 years with a failure rate of 0.1%/year
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