Hi everybody, I have a question 1

[Giuseppe76]

Hi everybody,

I have a question about a pig trap designed as per ASME VIII div 1 and which should be U-stamped.
I have received a comment told me that material like ASTM A694 F60/65 cannot be U-stamped cause is not listed in ASME VIII div 1.
Does anybody know if is possible to U-stamp material not listed in ASME VIII div 1?

Thanks
Giuseppe

 

[SnTMan]

Giuseppe76, it is possible but can be difficult. Turn to part UG-10 in your Code book.

Before proceeding, make sure your customer and your AI will accept the material.

Regards,

Mike



The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[LittleInch]

First and foremost, pig traps should not ever be designed to ASME VIII

They are part of a pipeline system and should be designed to your pipeline code which allows ASTM A694 ( well MSS Sp-44 does).

Whoever made this decision has made a significant error.

Pig traps are NOT Pressure vessels.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[LittleInch]

Guiseppe76,

I realise the answer may not be what you wanted to hear, but replies were provided and it is now down to you to respond in turn. That's how this site works.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Giuseppe76]

Hi Littleinch,

Sorry i am in vacation and not easy to reply.
Anyway, it was not that the question. Design is not up to me, and even if it could be as you sais, now i am facing another kind of problem.

Thanks
Giuseppe

 

[LittleInch]

Thank you for the reply. So if design is not your responsibility what is?

The same item can be used but with a revised design to B31.4 or 31.8.

Normally the issue is that the ID of the trap doesn't match the ID of the pipeline.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[weldstan]

Pig traps have been designed to ASME VIII but seldom stamped. And because the pig trap is a part of the piping system, it need not be stamped, at least here in the USA.

 

[SnTMan]

If designed to but not stamped the subject material may be acceptable.

On Edit: The complication is establishing plausible allowable stresses. Perhaps from another Code?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Giuseppe76]

Thanks to all for the replies.
The point is still there, despite the design rules, this trap has been designed as pressure vessel (probably wrong) and fabricator has purchased the ASTM material. This material is not listed in the Asme materials and, thus, not clear if can be certified by Asme with U-stamp. i have checked, and in my understanding, Asme could certify material not includes in their list but the process could take time. At the end, the best solution should be to derogate from contract and design the trapa as not pressure vessel.

Rgds
Giuseppe

 

[weldstan]

A Code Case will take some time to be accepted nd I have written a couple of Code Cases in the distant past. You must tell the purchaser of your plans and ask for the deviation to the Contract.

 

[LittleInch]

So if you're not the designer or fabricator, what is your role?

ASTM F60/545 is a forging material, commonly used for flanges or other fittings so you can weld to API 5L X65 to make use of the thinner pipe material.

If the main body is thicker than this you might be bale to cut the flanges off and weld different ones on which are acceptable ASME VIII.

Or re do the design to the pipeline code and see if the materials are thick enough ( almost certainly).

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Giuseppe76]

My company is the owner, designer is contracted to another entity and fabricator is sub contracted by designer.
I am the material/welding lead but design has been done during feed, now i am doing EPCIC, is clear now?

Anyway, i do agree with weldstan

Rgds
Giuseppe

 

[weldstan]

If you are the Owner and Purchaser of said equipment, you may change the design requirements at will provided the design meets Jurisdictional requirements. If your designer called out for such a design and Code stamping of his design which cannot be stamped, find yourself a new designer. He is obviously incompetent.

 

[GenB]

Hi. I got to say something,
UG-10 does not apply to this type of issues.
The ASME most likely will reject its use on code Works,
it locks tests that cannot be done afterwards. My opinion only.

General Blr. CA,USA