Experimental Study On Fault Diagnosis In Valve Of Reciprocating Compressor

The suction and discharge valves of a reciprocating compressor are the components which often fail. If the failure of the valves is not detected on time, it will cause further damage to the compressor. This paper presents an investigation on the detection of failure of suction and discharge valves in a 05G compressor which is used in a refrigerator of a trailer.The objective of the investigation is to establish a method and a vibration measurement system for diagnosing the valve failures in an 05G compressor. In order to reach this goal, the baselines of vibrations of the cylinder heads are first ascertained by measurement with a signal analyzer CAMD-6100 developed by Northwestern Polytechnical University. Then a suction or a discharge valve in one of the two front, central and rear cylinders is removed respectively, the same measurement and analysis are performed. The results of different cases are compared with those under normal condition. Evident differences have been revealed in the results. Finally the valves with given failure supplied by the manufacturer of the compressor are installed in different cylinders, the vibrations of the cylinder heads are measured and evaluated again with the same system CAMD-6100. Based on these results, a measurement method and criteria for detecting the valve failures in 05G compressors are developed and verified in the further proceeding of the investigation. The results show that the breakage of a suction or a discharge valve can be detected by means of the established method and criteria.