Compressor System Check Valve Failure Hazards

CONCLUSIONS 
Industry data supports expected check valve failure frequencies of between 1/10 years 
and 1/100 years. Lack of adequate maintenance and testing, fouling, corrosion and 
compressor surge are factors that can negatively impact check valve reliability in 
compression systems. Check valve failure can go undetected for many years even with 
an appropriate maintenance program that involves check valve inspection and 
refurbishing during all major turnarounds. Check valve failure scenarios can result in 
equipment overpressure in excess of 300% MAWP, excessive flare loading conditions, 
and compressor/turbine reverse rotation that can result in major mechanical damage as 
well as a gas release and fire. Simple settle-out calculations can be used to identify at-
risk systems. Where hazards exist, check valves should be classified as safety critical 
devices with appropriate maintenance programs implemented involving shop inspection, 
refurbishing and testing of check valves during every major turnaround. However, 
additional protective measures are frequently necessary to mitigate risks in order to 
comply with company risk mitigation standards as well as to achieve compliance with the 
ASME Boiler and Pressure Vessel Code. Where additional risk mitigation is needed, a 
number of alternatives exist to mitigate hazards, each with their associated advantages 
and disadvantages. 
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REFERENCES 
1. Williams, J. P., “Reliability for Safety Instrumented Systems,” Chemical 
Engineering Progress, pp. 27-32 (September 2004) 
2. King, R. E., “Auto-Refrigeration/Brittle Fracture Analysis of Existing Olefins Plants-
-Translation of Lessons Learned to Other Processes,” Journal of Hazardous Materials, 
Vol. 142, Issue 3, pp.608-617 (11 April 2007). 
3. “Dynamic Characteristics of Check Valves,” Val-Matic Valve and Manufacturing 
Corporation (2003). Access via: 
www.valmatic.com
4. “Guidelines for Process Equipment Reliability Data”, New York, AIChE Center for 
Chemical Process Safety. (1989). Access via: 
http://www.saunalahti.fi/~ility/
) 
5. McElhaney, K. L., “Failure Modes and Causes for Swing and Lift Type Check 
Valves,” prepared by the Oak Ridge National Laboratory (ORNL) for the U.S. 
Nuclear Regulatory Commission (1997). 
6. Hart, K., McElhaney, K. L., Casada, D. A., “Efforts by the Nuclear Industry to 
Evaluate Check Valve Failures”, presented at the Third NRC/ASME Valve and Pump 
Symposium, Washington, D.C., July 1994. 
7. Hart, K., “The Use of Check Valve Performance Data to Support New Concepts 
(PRA, Condition Monitoring) for Check Valve Programs”. 
8. “Safety Alert: Failure of the Backflow Protection System in a Hydrotreater.” Mary 
Kay O’Conner Process Safety Center, Centerline Vol. 8, No. 2, pp. 14-16 (2004) 
9. Sims, R. J., Yeich, W. G., “Guidance on the Application of Code Case 2211 – 
Overpressure Protection by System Design,” WRC Bulletin 498, (Jan. 2005) 
10. American Petroleum Institute, “ANSI/API Recommended Practice 521, Pressure 
Relieving and Depressuring Systems,” 5
th
Edition (Jan. 2007).