Reciprocating compressor prognostics of an instantaneous failure mode utilising temperature only measurements

Abstract

Reciprocating compressors are critical components in the oil and gas sector, though their maintenance cost is known to be relatively high. Compressor valves are the weakest component, being the most frequent failure mode, accounting for almost half the maintenance cost. One of the major targets in industry is minimisation of downtime and cost, while maximising availability and safety of a machine, with maintenance considered a key aspect in achieving this objective. The concept of Condition Based Maintenance and Prognostics and Health Management (CBM/PHM) which is founded on the diagnostics and prognostics principles, is a step towards this direction as it offers a proactive means for scheduling maintenance. Despite the fact that diagnostics is an established area for reciprocating compressors, to date there is limited information in the open literature regarding prognostics, especially given the nature of failures can be instantaneous. This work presents an analysis of prognostic performance of several methods (multiple linear regression, polynomial regression, K-Nearest Neighbours Regression (KNNR)), in relation to their accuracy and variability, using actual temperature only valve failure data, an instantaneous failure mode, from an operating industrial compressor. Furthermore, a variation for Remaining Useful Life (RUL) estimation based on KNNR, along with an ensemble technique merging the results of all aforementioned methods are proposed. Prior to analysis, principal components analysis and statistical process control were employed to create ! ! and ! metrics, which were proposed to be used as health indicators reflecting degradation process of the valve failure mode and are proposed to be used for direct RUL estimation for the first time. Results demonstrated that even when RUL is relatively short due to instantaneous nature of failure mode, it is feasible to perform good RUL estimates using the proposed techniques.

Methodology of Experimental Investigations of Valve Operation

“…If defects are found, they are eliminated, and then the valve is installed on the cylinder seat. If the valves have reached their service life, they must be replaced with new ones [7].…”

Evaluation of gas separator effect on operability of gas-motor piston compressor valves

“…It is studied in [10,11] that piston compressors are critical components in the oil and gas sector, although their operating costs are known to be rather high. Compressor valves are the weakest components, being the most frequent type of failure, and they account for nearly half of maintenance costs.…”

Failure analysis of refinery hydrogen reciprocating compressors

“…The early disclosure of wear symptoms will significantly reduce the costs of repair and will allow for repair planning. According to studies [1,2,6,8,9,10,12,14,15,22,25,29,30,31,32,33,34] conclusions can be drawn on damage or wear of components and functional units of reciprocating compressors on the basis of: However, it should be noted that the diagnostics of piston compressors is difficult in terms of interpreting the results. Single, independently recorded diagnostic symptoms can lead to false and often contradictory conclusions.…”