“TRL” is an acronym for Technology Readiness Level. This is a new acronym for me. I’m trying to learn more about it and its implications for mechanical seals — especially for API 682 5th Edition because the API lawyers are insisting that the TRL method and reference to RP-691 be added to API 682 5th Edition.
API RP-691 is a Recommended Practice from the American Petroleum Institute (API). An API Recommended Practice is a document that communicates recognized industry practices. In contrast to a Recommended Practice, an API standard appears to be much more binding and rigid. API standards typically include references to Recommended Practices.
API RP-691 is titled “Risk-based Machinery Management”. This 198 page document was published in June 2017 and is in its first edition. It is available through API; costs $163 and can be purchased here. Although I do not have a copy (and, apparently, API will not give a complimentary copy to the API 682 Task Force), RP-691 does not appear to have specific recommendations for mechanical seals. It does, however, include pumps. A preview of RP-691 is available here. Be sure to click on the “Look Inside” icon to get a preview of RP-691.
In its description, RP-691 is said to define “the minimum requirements for the management of health, safety, and environmental (HSE) risks across the machinery life cycle. It shall be applied to the subset of operating company and/or vendor defined high-risk machinery.” The proposed seal standard, API 682 5th Edition, certainly includes high risk machinery as defined in RP-691: high temperatures, pressures exceeding 600 psig and specific gravities less than 0.5 even though all services may not be high risk.
From other sources, I learned that Technology Readiness Levels range from TRL 0 to TRL 9 with TRL 0 marking the beginning of research and TRL 9 being proven technology. API appears to be assigning TRL 7 to machinery that has been used successfully in the field for three years. That being the case, seals having been successfully Qualification Tested per API 682 would probably be assigned TRL 5 or TLR 6 but I’m just guessing at this point.
I have no objection to API inserting the reference to RP-691 into API 682 and it wouldn’t matter if I did. I understand that the new TRL clauses are written somewhat generically in order to be inserted into other API standards as well. I was told that the same clauses would be inserted into the next edition of the pump standard, API 610. The API 682 Task Force was told that the paragraphs referencing RP-691 were mandatory and could not be edited or revised. My concern is that, as written, the new clauses appear to completely overlook the Qualification Tests of API 682 and leave evaluation up to the judgement of the purchaser.
Technology Readiness Level especially irritates me because, during the development of API 682 1st Edition, we were specifically told that field experience did not count. As a result, the seal OEMs were forced into conducting expensive Qualification Tests by the API some 25 years ago and have spent many man-hours and millions of dollars on those tests. If the TRL requirements had been available/required at the time of developing API 682 1st Edition, not only would those requirements have been incorporated into the 1st Edition but there would have been no reason for developing, much less conducting, the Qualification Tests.
Mechanical seals are a mature and proven technology. Every seal OEM almost certainly has products that have been around for 30 – even 60 years – and also has many end users that have achieved 6 to 8 year MTBR with their products. Therefore, a TRL rating of 7 for mechanical seals will quickly become the norm. The TRL requirements will soon be taken for granted and become meaningless and ignored except that the TRL will take precedence over the Qualification Tests.
Obviously, passing a Qualification Test will not and should not result in a TRL higher than the rating of 7 granted for 3 years of actual service. That being the case, why should a seal OEM bother with the Qualification Tests at all? I predict the demise of the API 682 Qualification Tests.
Here are some links for information about Technology Readiness Levels (TRL):
https://www.nasa.gov/directorates/heo/scan/engineering/technology/txt_accordion1.html
https://en.wikipedia.org/wiki/Technology_readiness_level