Investigation of Valve Failures Using Statistical Analysis of
Proof Test Data

Ransome; H. A.; Ukpaka; C. P; Nkoi; B.

doi:https://doi.org/10.56201/ijemt.v8.no3.2022.pg9.23

📄 Download Paper

Investigation of Valve Failures Using Statistical Analysis of Proof Test Data

Ransome, H. A., Ukpaka, C. P, and Nkoi, B.

Abstract

This research work examined pressure relief valve (PRV) failures by using statistical analysis of proof test data obtained from the computerized maintenance management system (CMMS) of Liquefied Natural Gas (LNG) facilities site. This study comparatively investigated the 30 months approved inspection interval for the proof test of PRVs by the Department of Petroleum Resources (DPR) of Nigeria. In this research, failure rate and failure behaviour of PRVs were evaluated and analyzed using bathtub curve. Aging effect of PRV using regression analysis and the cause of failures were also analysed. Least square multiple linear regression was the statistical tool used for the analysis with the aid of EXCEL. After thorough analysis, the study depicted drop in failure rate at different times (years) at the bathtub curve. Also, the statistical analysis found that the ageing effect from five spring loaded PRVs evaluated was at most 0.4% per year with 95% confidence and the amount of variance explained per time was minimal (R-Square 7.6%). It was recommended that the inspection interval (30 months) as approved by DPR for proof test of PRVs was optimal with regard to the required integrity condition of the PRVs since test frequencies yielded better result and consequently less risk. Also, further testing and investigation should be pursued to determine if longer intervals between inspections were possible. Furthermore, analysis from the investigation of cause of failure showed that corrosion was a cause of PRV failure and contact area factors such as sticking and cold welding.

Keywords

Aging trendHazard functionMaintenanceNormal distributionPressureRelief valvesReliabilityRatio.

References

Adadande, S. A. Naniwadekar, A.M.&Rajkumar, B.P. (2014).Reliability Analysis of Pressure Relief Valve Manufacturing System.International Journal of Emerging Research and Technology,2(2), 64-70. API, R. (1991). 527, Seat Tightness of Pressure Relief Valves.American Petroleum Institute (API) Recommended Practice, 527, 196 – 204. ASME PCC-3 – (2007).Inspection Planning Using Risk-Based Methods: Published by the American Society of Mechanical Engineers, 2007. Awati, M.V., Jadhar, S.G.&Vinay, G.P. (2014).Analysis of Pressure Safety Relief Valve UsingFinite Element Analysis.International Journal of Engineering Development and Research, 2(3), 2968 – 2973. Bukowski, J. V. (2007). Results of Statistical Analysis of Pressure Relief Valve Proof Test Data Designed to Validate a Mechanical Parts Failure Database. Technical Report, September, Exida, Sellersville, PA. Bukowski, J. V.& Goble, W. M. (2009).Analysis of Pressure Relief Valve Proof Test Data.Process Safety Progress, 28(1), 24-29. Bukowski, J. V., Gross, R. E. & Goble, W. M. (2011). Probability of Initial Failure for Spring Operated Relief Valves. In ASME 2011 Pressure Vessels and Piping Conference (585-595).American Society of Mechanical Engineers. Bukowski, J. V. Gross, R. E.& Goble, W. M. (2013). Investigation of Adhesion Formation in New Stainless Steel Trim Spring Operated Pressure Relief Valves. In ASME 2013 Pressure Vessels and Piping Conference (V05AT05A079-V05AT05A079).American Society of Mechanical Engineers. Chien, C. H., Chen, C. H. & Chao, Y. J. (2009). A Strategy for the Risk-Based Inspection of Pressure Safety Valves.Reliability Engineering & System Safety, 94(4), 810-818. Ebeling, C. E. (2010). An Introduction to Reliability and Maintainability Engineering.Tata McGraw-Hill Education. Emily, M., Robert, D. & Stephen, P. (2013). Evaluating Risk and Safety Integrity Levels for Pressure Relief Valves Through Probabilistic Modelling. Journal of Pressure Vessel Technology. 10(2): 13-15. Gross, R. E.& Harris, S. P. (2006). Extending Pressure Relief Valve Inspection Intervals by Using Statistical Analysis of Proof Test Data.I ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. American Society of Mechanical Engineers. 4, 211-219. Gross, R. E.& Harris, S. P. (2008).Analysis of Safety Relief Valve Proof Test Data to OptimizeLifecycle Maintenance Costs.In Reliability and Maintainability Symposium, 2008.RAMS 2008. Annual,312-316. Hellemans, M. (2009).The Safety Relief Valve Handbook: Design and Use of Process Safety Valves to ASME and International Codes and Standards.

Investigation of Valve Failures Using Statistical Analysis of Proof Test Data

Abstract

Keywords

References

More Articles from INTERNATIONAL JOURNAL OF ENGINEERING AND MODERN TECHNOLOGY