RPad at Tee

[marchieV]

Good Day!

I just want to ask regarding the Reinforcing Pad on a tee.
The existing header and branch has RPad of 4.75mm BUT based
on the stress analysis report the RPad required is 7.92mm.
The construction engineer inform us that they will just add
another plate (RPad) in the existing RPad (4.75mm) in order
to compensate the required 7.92mm.
My question is, is there any code or standard that deviates
the adding of another plate(RPad)? [4.92mm + ??? Plate = 7.92 mm]
Also, what will be the consequances or negative effects of these
additional plate?

Thank you in advance.

 

[LittleInch]

What piping code is this to?

There should be guidance in there, but I'll be honest, it sounds like a quick fix to me which shouldn't be allowed.

How are they intending to join the two plates together?

My instinct is that unless the code specifically lets you do it, tell them it's not covered and do it properly.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[marchieV]

LittleInch,

Actualy the plant is already too old that is why the construction team
are afraid to replace the RPad of the tee specialy it is 45deg. tee and they
are also afraid that by replacing the RPad might cause fatigue on the tee.

Regarding the process of joining the two RPAd, actualy I have no idea
about it but one way I think is by welding it in the side.

Maybe you have another way to solve the problem.

Thank you for your reply.

 

[LittleInch]

My way is to cut out the tee and fit a proper one.

Anything else is a bodge.

IMO

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[TGS4]

I think that you need to get a second opinion on what reinforcing pad is actually required. For in-service equipment, regardless of Code of Construction, I would recommend getting an API-579 Fitness-For-Service assessment performed. For a 45 degree tee, you will be looking at a Level 3 assessment.

I don't think that slapping an additional plate on top of an existing reinforcing pad will do much. And completely replacing an existing reinforcing pad will not, in and of itself, cause fatigue.

 

[marchieV]

TGS4 & LitteInch,

Thank you for your advice.

I'll consider all your opinions.