Diagnosis of reciprocating compressor pistoncylinder liner wear fault based on lifting scheme packet

Key words:  lifting scheme packet  reciprocating compressor  wear  signal decomposition  diagnosis

Abstract:

Aiming at characteristics identification problem of weak signal for pistoncylinder liner wear fault of reciprocating compressors,a novel method to design adaptive undecimated lifting scheme packet (AULSP) was developed and applied to identify successfully weaksignal fault features of a certain reciprocating compressor. The minimum square sum of prediction difference of all sample points was taken as object function, and the initial operators that adaptively match the weaksignal features were calculated, then undecimated operators were constructed and used to calculate each frequency band on the next level. Noise can be restrained via thresholding operation. The signal length of each frequency band was the same as that of the original signal, thus timedomain fault features could be recognized without reconstruction. AULSP was applied to identify weak periodic impact signals caused by pistonliner wear.