does a 300# Gate Valv LCC body API Trim 12 meet NACE MR1075-2003

[Gorman3]

I supplied these valves to a company who now claims that they do not meet the NAVE MR107-2003 (not the combined ISO version). I believe that if they don't meet the spec the reason would be that a trim 12 valve cannot by nature meet that spec, and therefore they should have ordered something else.

My NACE valve are always stressed relieved, use NACE compliant bolting and are checked for hardness check. In all these years we have never had this complaint. So I am thinking that the customer should have ordered a different valve in the 1st place.

Can anyone confirm? I'm digging thru this mess of a spec but am having trouble finding an answer.

thanks

PS - they have also claimed a

 

[SJones]

Being an international guy, I only work with ISO 15156!!!! Anyway, as Trim 12 is essentially 316 and, therefore, comes under Table A.2 of Technical Circular 1, 2007, you will note that you have two options:

1. max 60 deg C and/or max 1 bar a partial pressure H2S

or

2. maximum of 50 ppm chloride in the fluid

In each case, the material has to have a maximum hardness of 22 HRC.

So, how does your material fail to meet the requirements?

Either way, it is up to the end user - not you - to work out whether the valve materials and the environment they will see meet these restrictions.

Did they explicitly state the environment?

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[reverman]

NACE MR075 compliance is completely dependent on environment

If you have conditions that allow the use of carbon steel and 316 stainless steel. Then you should be okay neither material should be over 22HRC.

One caution that probably is'nt an Issue with an LCC valve But may be a problem with WCB or WCC valves. Some manufactures use solid 410 stainless as a standard for wedges and backseat bushings on Trim 8 valves. if this valve was converted from trim 8 to trim 12 the 410 parts may still be in the valve with 316 or stellite overlays on them. If that is the case the 410 stainless is not NACE compliant.

 

[GainControl]

reverman,

Why do you say 410 stainless is not NACE compliant?

Table A.18 in NACE MR0157/ISO 15156-3:2003(E) lists S41000 "...for any equipment or components".

Thanks.

 

[reverman]

410 is only compliant if it is in the double annealed condition. Which as a standard it usually is not.