Welding AR plate to SA516-70 Code issues?

[acaughey]

Hi All,
I have a pressure vessel where my customer wants AR plate welded to the interior of the vessel at the product inlet. Is anyone aware of any code issues with this or can someone point me to a section in the code that talks about this?
Thanks,
Aaron

 

[metengr]

I have a pressure vessel where my customer wants AR plate welded to the interior of the vessel at the product inlet. Is anyone aware of any code issues with this or can someone point me to a section in the code that talks about this?

If the AR (abrasion resistant) plate is subjected to pressure, it is not permitted for use in the vessel. This is described in ASME Section VIII, Div 1 General Requirements.

 

[acaughey]

Thanks for you response. The AR plate will be welded to the inside of the vessel and is not intended to contain pressure. The shell of the vessel is SA516-70 which will be containing the pressure. Essentially my customer wants a thicker harder wall at the product inlet, I suppose you could look at it as welding a baffle plate of AR inside the vessel. I dont know if I explained myself very well, but do you think this would be permitted?
Thanks

 

[vesselfab]

it's permitted as long as the plate is identified with an MTR and a p-no so a welding procedure can be assigned.

 

[metengr]

acaughey;
AR plate is abrasion resistance high stregnth low alloy steel that has no P-No. To make this task easier you might want to investigate a weld overlay on a carbon steel substrate. The overlay can be tailored for abrasion resistance. The qualification of the weld overlay is straight forward and is not considered part of the design of this vessel, in other words, you can design the overlay as a barrier coating.

 

[unclesyd]

We use weld overlay quite often in flash tanks and other process with tangential entry.

We mainly use Hastelloy C as a weld overlay as it gives us abrasion and corrosion resistance along with easy application.

 

[acaughey]

All,
Thanks for your responses, I will check into a weld overlay.

 

[JoeTank]

vesselfab,
I am assuming that the AR plate will be welded to the pressure boundary and will not be required to resist pressure loads. If true, I don't beleieve that ASME VIII requires that the material have a P-number. It does state that it must be of weldable quality and mentions a carbon content limit (35%, I think... Code not in-hand now). If a welding procedure can be qualified per ASME IX, then it's of weldable quality material (again, Code not in hand, so I can't cite the pp). I think these statements are in UW-5 and UG-10. I have seen numerous applications of AR material in ASME VIII vessels. Some worked well, some did not.

Personally, I have always required an ASME-listed material for items that weld to the pressure boundary. But, sometimes it is just not possible.

Joe Tank

 

[metengr]

JoeTank is correct, it is UW-5 (b). A Section IX, WPS must be qualified to demonstrate proof of acceptable weld quality in addition to the carbon content being less than 0.35% by mass. The AR plate specification must be listed on the WPS.

 

[vesselfab]

I stand corrected.

Our shop practice becomes engrained and start thinking it is rules.

Old School....we track heat number for every piece of material and must have SA specification.

We don't do weld procedures without p no.

Like i said....just old school thinking.

 

[JoeTank]

vesselfab,
Nothing wrong with old school. It typically represents best practices, but sometimes it takes on a life of it own as to whether it's a Code requirement or a corporate policy.

Joe Tank