Lamination Test Of Pipes According to ASME B31.3

[mmbguide]

hello to all

our design code is asme b31.3 and we want to get the pipes lamination examination, which reference is practicable for that? dose asme b31.3 have any suggestion for that?

thank you

 

[XL83NL]

Lamination examination? You mean to verify the through thickness, also known as the z-test? B31.3 does not address this. Either the product standard may (e.g. ASTM), the client specification, or your own supplemental purchase order spec. In any case, B31.3 does not have any suggestion for that, other than the general remark that ‘materials shall be free from ... ’.
In general I can’t quickly think of a situation where your pipe is so thick and fabricated in such a way, that one should concern about laminations.

 

[MJCronin]

It is my understanding that the ASME/ASTM piping materials permitted for use in B31.1 and B31.3 are of such a quality level that lamination is never a concern.

ASME B31.1 and B31.3 do not permit the use of any material.

I am aware that some thick carbon steel sections used to construct structures must have an examination for lamination defects

MJCronin
Sr. Process Engineer

 

[Dhurjati Sen]

Dear mmb

Lamination is a rolling defect.
It is a common occurrence where plates are involved, for example, in the construction of storage tanks. However, for large diameter pipes which are made from plates, lamination is an issue.

You can find out lamination by ultrasonic testing.

Before ordering the pipes, check the ASTM specification for any Supplementary Requirements that puts a check on inclusions etc. and subsequently laminations.

I have come across situations that after years of service, lamination in large diameter pipes have been misreported as HIC !!!

DHURJATI SEN

 

[weldstan]

Primarily service conditions should dictate the need to check for lamination. UT is the method to determine freedom from lamination. Your P.O. for the pipe should indicate requirements for testing. Practically it should only be done on welded pipe made from rolled plate/skelp. If ordering direct from the pipe mill, UT could be done on the plates prior to forming and welding.