SA 516 Grade 70 plates in stead of SA 516 Grade 60

[hirendhara1234]

For Pressure Vessel SA 516 Grade 70 plates can be used instead of SA 516 Grade 60 if all properties in Material test certificates are matching?

 

[Duwe6]

I'm inclined to say YES, but would need more info to make a better determination. Do you mean that your Gr.70 material will also meet all the allowable ranges of Gr.60? If so, that is definitely a YES.

 

[marty007]

It's important to understand why the customer may have wanted SA-516-60 in the first place.

One industry where I see this is for sour service applications where a softer material is desired. I have seen specifications where the customer also adds a note where the maximum tensile strength may not be more than x-ksi above the material specified minimum.

This can sometimes be worked around though. If the customer were to specify SA-516-60 with a maximum tensile say 20ksi above the minimum, you would have an allowable tensile range of 60-80ksi. If you can find SA-516-70 plate with a tensile less than 80ksi, the customer may agree to its usage. This requires some more careful oversight on the purchasing side and checking mill certs.

This is one situation where you have to be careful with such a substitution, it's important to understand WHY they wanted SA-516-60.

(On the other side of the coin, sometimes plant operators are just replacing old equipment and don't know any better...)

 

[weldstan]

SA-516 is often triple certified to 60, 65 & 70. See Marty007 re other reasons to only use grade 60.

 

[GenB]

In my area 516_60 is almost non existing. 7o is the norm unless its a repair.