Material selection issues for Pressure vessel

[arksurat]

I am making a pressure vessel as per ASME VIII div I for
crude oil seperator. My design pr/temp are 1440 psi / 100 DegC.

Shell material: 32mm thick, A 516 gr70 plate.
If I procure normalised plate, is it required to carry out
any SR / normalising after rolling prior to welding?
Is it mandatory as per code to order ultrasonically tested plate?
If so, as per which ASME standard (A435 / A577 / A578)?

Piping Material : API 5L X52 grade
As per API there are 2 classes PSL1 and PSL2.
Which class is required for my application?

 

[twjag]

See ASME Sect VIII, Div 1 UCS-56 for PWHT requirements.
See UCS-79 for heat treatment requirements for formed shells & heads.

See ASME Sect VIII, Div 1 paragraphs UG-4 & UCS-5 for material requirements, including pipe. API pipe may not be used for pressure parts, unless also certified to an ASME Mtl Spec listed in, & allowed by, ASME Section IID.

 

[arksurat]

The code refers to ASME Part II A for selection of material.
As per part II, SA 516 Gr70, UT is only optional / SR.
So my interest is to locate the guide lines in selecting the
appropriate UT code in my case.

 

[JamesBarlow]

Every vessel that we make, even non-coded vessels, are UT'd. The cost of this, in our case, is rather small compared to the overall cost of the material so we take the conservative approach.

The lowest pressure I have ever dealt with is 5,000psi so an inclusion in the material could cause a lot of problems, possibly killing someone.

I would get the UT done even if you don't think it needs it. That peace of mind knowing the material has been tested is worth a lot more than the cost of the test.

 

[twjag]

Material Specification SA 516 lists Supplementary Requrement S8, S9, & S11 for UT Examination, & the applicable Specification for each. Review the listed Specs & determine that which best fits your conditions, or the customer's requirements.

 

[Halket]

Q1) "Shell material: 32mm thick, A 516 gr70 plate.
If I procure normalised plate, is it required to carry out
any SR / normalising after rolling prior to welding?"
A1) No material treatment is required PRIOR to welding.

Q2) "Is it mandatory as per code to order ultrasonically tested plate?"
A2) Ultrasonic testing is normally used when the material is sufficient thickness to cause concerns about possibility of laminar separation or when the material is bonded (to check for separation between backing and liner).

Q3) "Piping Material : API 5L X52 grade
As per API there are 2 classes PSL1 and PSL2.
Which class is required for my application?"
A3) This decision is partly based on a review of your COMPLETE service conditions.

Hope that this helps....

Steve Halket
halket2@yahoo.com