316/316L 1

[BrunoA]

Hi all,

I'm designing a pressure vessel using some 10in NPS pipe, and I would like to know if I can use this kind of material. We have pipe we would like to use that is certified 316/316L. When we checked the boiler and pressure vessel code it lists pressure and temperature ratings for 316 stainless up to 1500 degF but the 316L rating doesn't go as high. I would like to know if anyone can tell me, preferably with a link to the source, what the pressure temperature ratings for 316/316L are. Moreover, I need to make sure that they are as high as (or close to) what the code lists for 316.

Thank you for the help,

Bruno

 

[rneill]

Material that is certified 316/316L is dual graded in other words it fully meets the requirements of both the regular 316 Grade as well as the low carbon 316L grade.

In cases like this, you are permitted to use the properties listed for either of the two materials: 316 or 316L.

There is a code interpretation on this somewhere I'm sure but I don't have the reference right now but if you wanted to scan through them, you should be able to find it.

 

[BrunoA]

thanks for the quick response. which code are you referring to for me to scan for this info? the only info I've found only refers to the chemical composition of the material. have you seen anything that specifically lists pressure/temp. ratings for the dual certified 316?

 

[vesselfab]

nothing is listed as dual certified

the pipe and fittings meet both specifications

if you are required to use 316 use the 316 charts

if you are required to use 316L use the 316L charts

 

[BrunoA]

It's not that I don't believe you, or the salespeople or everyone else who's told me the same thing, but my managers want me to show them some code or reference that spells it out a bit more directly (preferably with regard to the pressure and temp. ratings). Does anyone have a code or material spec. they could refer me to?

 

[JStephen]

You need to get your supplier to confirm that a "361/316L" means that it meets both 316 and 316L requirements, which would be the common understanding. Or you could compare your mill test reports to the ASME spec.

 

[jte]

Bruno-

Pull out Section II-D 2009 and flip it open to page 892.

A common inquiry topic is the permissibility of using material that is identified with two or more specifications (or grades, classes, or types), even if they have different strengths, or even if one of them is not permitted for use in the construction code of application. The Committee has addressed variants of these questions in several interpretations: I-89-11, IIA-92-08, VIII-1-89-269, and VIII-1- 89-197.

The rest goes on to answer your question in more detail. You might have to pay attention to carbon content in the MTR. Enjoy!

jt

 

[jte]

Also, don't forget to read the notes in II-D Table 1A as listed for your particular material. Note G12 applies to SA-312 316 materials and clarifies the required carbon content. Your material may be dual certified as meeting the requirements of both the straight and L grade chemistries, but this note becomes part of the requirement under your situation - and may disqualify the material.

jt

 

[MrBTU]

ASME Code Interpretation:
Interpretation: VIII-1-86-187
Subject: Section VIII, Division 1, UHA-1
Date Issued: December 14, 1987
File Number: BC87-424
Related Documents: VIII-1-89-65

Question: Stainless steel materials have been received from suppliers with dual markings and dual certifications for 304/304L and 316/316L. Material test reports show that the material meets all the chemical and physical requirements of Section II, Part A for the specific material. May this material be used in the design and construction of both plain grade and low-carbon grade stainless steel vessels?

Reply: Yes.

 

[curtis2004]

BrunoA,
What section is your vessel built? For what service?

 

[BrunoA]

Section I for superheater tubes rated at 1500 deg F.

 

[michigander]

I don't understand your managements concern regarding a very common industrial practice. Materials are commonly dual certified. In the 70's and 80's it was common to use SA-53B grade pipe in pressure vessels that was also dual certified as API-5L pipe. Does the API cert preclude you from using it as ASME material? Nonsense! If the manufacturing processes and chemical compositions meet the requirements of 4 different specifications, you can quadruple certify a material.

I regularly design 316L vessels using the higher allowables of 316 as long as I am sure the material will be dual certified.

Michigander

 

[BrunoA]

Thank you all for the feedback. We were somewhat unfamiliar with this situation as we've not had to use this material at the elevated temperatures that we're dealing with for this design. Between this thread and code interpretations (as mentioned above), we've reached a consensus to move forward with this material.

Thanks again,

Bruno