Differentiating between SA 106B and API 5L X-42

[LISAEK]

What is the best way to identify an line already in service as SA 106B or API 5L X-42 using non-destructive techniques? The carbon contents are similar so I don't think we can use carbon content. How does X-42 get it's strength - by heat treatment? Do other elements play a role also? Thank you for your help.

 

[Metaljon]

Not easy as the chemical composition can overlap. The Manganese on the X42 has a slightly higher upper level of 1.3wt% compared to ASTM A106B which has a maximum of 1.06wt%. Try using a PMI chemical analyser.

 

[LISAEK]

Metaljon, thank you for your information. Lisa

 

[stanweld]

Most A-106B pipe is certified by the manufacturers as A/SA-106B, A/SA-53B, API 5LB and API 5LX-42. So it will be very difficult to ascertain which is which. Also check Si content. A/SA-106B is fully killed, whereas A-53 and the API pipe may or may not be. You should not consider X-42 as a "high strength" steel; however the increased Mn max does provide the manufacturer the ability to increase the carbon equivalent when increased thickness dictates the need to achieve the SMYS.

 

[LISAEK]

Thanks, Stanweld. I knew it could be stamped for multiple grades so appreciate the help. Lisa