Leakage Reduction on Seal Parts of HFC134a MAC Compressors

Typical belt-driven Mobile Air-Conditioning (MAC) compressors require durable seals between a rotating driveshaft and stationary casing in addition to casing and hose connection O-ring seals. This paper explores the experiential and theoretical relationships of HFC134a seal design and materials and also suggests possible improvements.

Testing revealed that shaft and O-ring permeation comprised a large part of the total leak rate of HFC134a MAC compressors during static-state leak-rate measurements.

Furthermore, testing and Taguchi statistical analysis methods clarified equations concerning permeation area, distance and leak rate. Resulting design and material improvements reduced compressor HFC134a Leak Flow Rates (LFR) by approximately fifty percent.