R290 has been considered for use in air-conditioning systems as a low global warming potential (GWP) refrigerant. This paper describes the tribological characteristic of the vane-piston tribopair in a R290 rotary compressor. For the purpose of simulating the tribopair working conditions

the vanes and rolling pistons of a compressor were directly adopted as test specimens. All of the tribological tests were performed under sealed high-pressure conditions

with test conditions such as the relative sliding speed

loads

and temperatures set based on actual operating conditions of a compressor

and the friction coefficients

scuffing resistances

and wear depths were measured. Furthermore

the morphological changes were investigated using a scanning electron microscope after the tests. As a comparison benchmark

tests were also conducted using R410A/polyolester oil. From these tests

it was evident that the friction coefficients and scuffing load of the vane-piston interface in the presence of R290/mineral oil were respectively 0.05–0.1 and 300 N higher than those of R410A/polyolester. On the other hand

the wear resistance ability with R290/mineral oil was better than that with R410A/polyolester.