In 2014 API revised Standard 520 (and 521) including omitting a portion of the Standard's title where "in refineries" was omitted. This change now impacts PSV's for the upstream production portion of the industry. Is compliance retroactive to 1972 or only to the effective date of the revision?
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Api 520/521
#1
Posted 07 December 2016 - 07:32 AM
#2
Posted 08 December 2016 - 09:46 AM
As I know, API 520/521 has been applied in the oil/gas upstream PSV and pressure-relieving system designs for much earlier than 2014.
#3
Posted 11 December 2016 - 05:01 AM
Dear,
It is important to note that API 520 was a "recommended practice" (RP) up to the year 2000, 7th edition. Since 2008 it is a standard. Similarly API 521 was a RP up to 1997. It became a standard API STD 521 since 2007, 5th edition.
What this implies is that if you are mentioning in your engineering documents the reference as API STD 520 / 521 for PSVs and this reference is accepted in the base design document by the client, then you are mandated to use the content including equations / formulas for PSV sizing and the client has to accept it. Since it is a standard and not a recommended practice this can also be used as an admissible evidence for any litigation in a court of law involving any industrial dispute related to PSV design.
Regards,
Ankur.