Development and Validation of a Bench Test Procedure for Post Mortem Testing of Relief Valves

摘要

In 2007, IIAR revised its recommended practice for replacing pressure relief valves on industrial ammonia refrigeration systems [Section 6.6.3 of Bulletin 110]. In addition to the prescriptive five-year relief valve replacement interval, the revisions to Bulletin 110 added an alternative replacement method based on an evaluation of in-service relief valve life using appropriate testing and data analysis methods. This paper describes the results of a research project that aimed to validate guidelines for the postmortem testing of relief valves. The purpose of the data collected by post-mortem testing is intended to support the alternative path to determine the service life of relief valves following their removal from the system prior to their disposal (i.e. post-mortem]. The testing procedure and data gathering methods described in this paper are intended for relief valves that have not discharged during their in-service life. A test rig suitable for post-mortem testing of relief valves was designed, constructed, and proof-tested. The function of the experimental rig was established by testing a range of alternative relief valves that included high and low set pressures; high and low capacities; as well as both new and used relief valves. The draft test procedure was modified using the information gathered during the rig proof-test. The results of this project include a relief valve test rig design and corresponding test procedures suitable for data collection by post-mortem testing of relief valves.