API 510 for Non-Pressurized Vessel

[mp08]

We are currently developing an inspection program for my company. We have several reactors that are kept under vacuum/atmospheric pressure. The only pressure is from the raw material pumps into them and the nitrogen blanket, which is only a few inH2O. These reactors were made under ASME Pressure vessel code with a MAWP of 43.5 psi.

I was going to setup the plan based on API 510 (for pressure vessels) initially since we have no data, but was looking at the exemptions part of the standard. My question is would these reactors fall under API 510 or not? They are made so they can be run up to 43.5 psi, but we have nothing that can generate that pressure (except for hazardous side reaction) or run at that pressure. My old company followed API 510 for all vessels (except storage tanks) but I'm not sure if that was an industry practice.

Thanks

 

[GulfCoastInspector]

I believe the answer to your question can be found in the first sentence of
API 510 TENTH EDITION, MAY 2014
Annex A
(normative)
Code Exemptions
The following classes of containers and pressure vessels are excluded from the specific requirements of this
inspection code, [highlight #FCE94F]unless specified by the owner/user.[/highlight]

Best of luck,
Larry

 

[Duwe6]

You are using these vessels 'in the manner of API 620', i.e. less than 15 psi, but well above ambient. Thus you get to pick either API 510 or API 653 for your Inspx directives. OR you could write your own spec for how and when to inspect these vessels.

FYI, I typically use 653 for Inspx of low-pressure [620] vessels. 510 is pretty much for actual pressure vessels [ > 15# ]. But whichever one of the three choices - 653, 510, house spec - you are required to follow it. Refusing to follow the chosen spec/procedure is one of the major items that OSHA looks for when auditing PSM programs.