Sealing Performance of a Mobile AC Compressor Shaft Seal

摘要

In the last years, environmental concerns such as the destruction of the ozone layer and global warming led to the demand of tighter air conditioning (AC) systems. The compressor has been identified as the most emissive component of the AC system. Due to its complex structure and sealing mechanism, the shaft seal is the leak-prone part. This paper presents an experimental study of several lip seal designs to characterize the gas leakage among contact surfaces and through the polymeric lips. An original experimental setup has been developed in order to measure the gas leakage throughout the seal and to visualize the polymeric lips deformation in standstill mode. Leak rate measurements were carried out by measuring the variation of HFC-134a concentration inside an accumulation volume using an infrared gas spectrophotometer. The gas pressure and the shaft surface roughness impact on those results, as well as the presence of lubricating oil in the sealing zone are discussed.