Compressor Body Temperature and Lubrication 2013-01-1501

The paper addresses compressor body temperature (crankcase) importance to the vehicle AC system long-term durability. Majority of OEM vehicle test evaluation is to see if AC system can pass compressor discharge temperature and discharge pressure targets. Most OEMs adopt 130°C max compressor discharge temperature and 2350 kpag head pressure as the target. From the field, although some of the compressor failure results from a high compression ratio, and compressor discharge temperature that are caused by the poor front end airflow, etc., high percentage compressor failed systems exhibit not too high compression ratio and compressor discharge temperature, but having the trace of high temperature in the shaft area, gasket area, etc. With introducing more and more variable swash plate compressor applications, OEMs start to see more and more compressor failures that are not related to a high compressor discharge temperature but the trace of high compressor body temperature. Higher compressor body temperature than a compressor discharge temperature exists in the normal vehicle operation in addition to traditional compressor VDA (Verband der Automobilindustrie) test (high compressor ambient temperature conditions).

The compressor healthy lubrication concept is proposed to evaluate the compressor long-term sustainability in the paper.