WEAR TESTS OF SLIDING SURFACES IN THE ENVIRONMENT OF MIXTURES OF LUBRICATING OILS AND REFRIGERANTS

Abstract

Elements of refrigeration compressors may be exposed to various types of wear processes, depending on the used oils and refrigerants. The presence of the refrigerant makes the lubricating properties and anti-oil mixture - factor much worse than in case of the lack of refrigerant oil. Current regulations on the use of ODS phase-out of working require refrigeration synthetic refrigerants HCFC (e.g. popular R22). The paper presents the effect of different mixtures of oils and refrigerants on friction coefficient and surface condition of cast iron and aluminium PA6. Tests were performed on a prototype machine using frictional node type block-on-ring, which is located inside a pressure chamber that simulates the refrigeration compressor. The results of the study confirm the possibility of using green refrigerant R290 (propane) as a substitute for R22, while keeping the existing mineral oil.