Dual grade material

[Pipeline10]

Hi,
I appreciate any feedback on this. I need a ASTM A572 Gr60 material for welding procedure development, but vendor is offering A572 Gr50 which meets all chemistry and mechanical properties of Gr 60. MTR is not stating dual grade. Can I use this material as a dual grade material and qualify welding procedure for Gr60?

 

[metengr]

Are you qualifying the WPS to Section IX or other code, like API?

 

[Pipeline10]

I am qualifying for both Section IX and API 1104.

 

[metengr]

Not an issue for ASME Section IX because both material grades are the same, P-No 1, with different group numbers. For API 1104, you need to have dual certified material or material specified to Grade 60 to qualify for the higher yield strength material.

 

[Pipeline10]

Thanks! What do you mean by dual certified? Is the MTR require to state that or if mechnical properties and chemistry matches both grades we can use it as a dual certified?

 

[david339933]

Remember if impacts are applicable, group # becomes an essential variable and grade 50 will not qualify grade 60.

 

[metengr]

Is the MTR require to state that or if mechanical properties and chemistry matches both grades we can use it as a dual certified?

Yes.