API 607 Qualification for material change

[JY AN]

It is certified as a ferrite-based component according to API 607.
If I change the material of the bottom cover, disc, and stem to Nickel-Aluminum-Bronze or other metal, do I need to obtain a new certification?

 

[bcd]

Your situation is not clearly addressed by 607. Per section 7.2, you may either need to test a single valve to extend the material change from the ferritic tests, or test the full range. It depends upon how your interpret the first and last sentences of paragraph 7.2.3. Either way, your described material change requires a test. How many tests is not clear.

For another possible viewpoint, you can look at ISO 10497. At one time, it was a combined standard with 607, and it has additional words in paragraph 7.2.3. It adds, "testing of low melting point alloys, e.g., aluminum bronze, shall be limited to valves rated PN10. PN16, PN25, and PN40, Class 150 and Class 300." Not sure if this is relevant to your situation or not.

You will only get opinions in this forum. If you need something official, you need to submit an inquiry to the API standards committee. You can do this through their website. There is a link for requests for interpretation. Would be good to submit now as I believe the standard is currently being revised and your inquiry may inspire them to clarify the standard.

https://www.api.org/products-and-services/standards

 

[Nick_Gray_88]

Having been in your situation previously there is only one answer which customers will accept and inspectors will approve.

You have to consider any material outside of the three groups as individual alloys ( this extends to bolting too). I.e. you will have to test from scratch for each of these materials.

When you did your original test you could have used for trim components the worst case materials, then you could justify the continuation of the approval to better-case materials by desktop assessment.

This all stems from the historical view that low melting point alloys were fire safe but could not be tested; which as ISO 10497 shows is rubbish.

 

[HitokiriAoshi]

We are working on 607.. but the whole point of the fire testing is to demonstrate that a particular valve, after being in fire for 30 minutes (Average time to put out fire in refinery), can still maintain some level of control of media.. the key things on these valves is mainly the fastener material, fire safe gasket usage, and usage of spring (floating ball valves).

on larger valves, the soft goods don't even burn out.

most users will accept whatever certificate you have, if all you do is change some minor parts. the users that want to give you problem, will give you all kind of problem (like what nick gray was talking about). focus on 7.2.5 which describe which component is the key in triggering a re-test requirement, and try to talk to people who ACTUALLY know the standard, than some random "inspector"

Luke | Valve Hax |

https://valvehax.com/