THE FRICTION AND WEAR BEHAVIOR IN CONTROLLED ALTERNATIVE REFRIGERANT ATMOSPHERE

Increased wear occurred in the actual refrigeration compressor when HF C refrigerants were substituted for CFCs to comply with the Montreal P rotocol. A cause of this increased wear was believed to be the inferio r extreme-pressure (EP) or antiwear capability of the alternative refr igerant HFC-134a as the environment gas, compared to that for CFC-12 r efrigerant which is currently used. However, under some severe conditi ons, it was found that the alternative also showed some antiwear or EP effect by forming a fluoride layer on a sliding surface. The reason H FC-134a did not exhibit a lubricating effect, even though it had some capability to form a fluoride layer, was that the sliding condition re quired for HFCs to form a protective layer was more severe than that o ccurring in actual compressors, The mechanism of the atmospheric effec t of refrigerant gases on friction and wear is also discussed.