%T A case study of reliability assessment for centrifugal pumps in a petrochemical plant
%A M. Muhammad
%A M.A.A. Majid
%A N.A. Ibrahim
%C Athens
%P 398-404
%X Centrifugal pumps are widely used in petrochemical industry and in some instances, the number of pumps used could easily amount to hundreds of pumps in a typical petrochemical plant. Consequently, the reliability of these pumps essentially translates into stable and reliable plant operation as the pumps performances are critical in ensuring continuous plant productivity. Reliability assessment for repairable equipment, which in this case centrifugal pumps, is highly dependent upon the assumption of the state after each repair. The post repair states can be categorized into three different states namely, 'as good as new', 'as bad as old' and the states in between. In practice, however, the usual state of equipment after repair follows the state of 'better than old but worse than new' which lies somewhere in between the two extremes. This paper focuses on the reliability assessment of the centrifugal pumps at a refinery plant that has been in operation for more than 10 years using a more robust process called generalized renewal process (GRP). This process has been proposed to model not only the 'inbetween' states but also the two extreme post repair states. A case study utilizing centrifugal pump failure data is used as a comparative appraisal of reliability assessment between GRP, perfect renewal process (PRP) and non-homogenous Poisson process (NHPP). The underlying distribution for time to first failure for these pumps is assumed to follow the two-parameter Weibull distribution and the parameters for the models are estimated using maximum likelihood estimation (MLE). The GRP solution based on the case study showed better description of the failure distribution even with limited available failure data in contrast with other assumptions as indicated by the likelihood values.
%K As bad as old; As good as new; Continuous plant; Failure data; Failure distributions; Petrochemical industry; Plant operations; Poisson process; Pump failure; Reliability assessments; Renewal process; Repairable systems; Underlying distribution, Asset management; Centrifugal pumps; Life cycle; Maximum likelihood estimation; Petrochemical plants; Poisson distribution; Pumps; Reliability analysis; Research; Weibull distribution, Repair
%O cited By 11; Conference of 4th World Congress on Engineering Asset Management: Engineering Asset Lifecycle Management, WCEAM 2009 ; Conference Date: 28 September 2009 Through 30 September 2009; Conference Code:94588
%J Engineering Asset Lifecycle Management - Proceedings of the 4th World Congress on Engineering Asset Management, WCEAM 2009
%L scholars540
%D 2009