Replacement of Weld Reinforcement (Cap) 3

[niconieuwoudt]

thread292-158295
During Construction Phase and Installation of Process Piping, especially where piping flanges join up to rotating equipment, are very sensitive for alignment purposes. Some pipe spools are received from different parties (fully welded) and the pipe flange does not align properly (paralelism)with the equipment(pump) flange. The procedure to perform a proper alignment, is to grind the weld reinforcement (Cap) on a specified area and re-weld this grinded reinforcement. This added heat and cool off process, is just enough to align the two flanges.
The questions are:
1)is this an acceptable procedure?
2) as per ASME B31.1 Para 328.6,is this procedure regarded as a weld repair?
3) Which International Standard refer to this type of alignment practice.

 

[metengr]

So in other words, you are locally excavating material and using residual stresses from welding the excavation to pull the pipe into proper alignment.
If this is the case, as long as the welding is performed using a qualified welding procedure for the correct base material, certified welder and required nondestructive testing (NDT) is performed in accordance with the original code of construction requirements, this should be acceptable.
Yes, the operation above would be considered a weld repair because regardless of the reason for the excavation you are performing welding to restore possible wall thickness and/or the original weld contour.

 

[ramy123]

Nico
By the reinforcement cap you mean at the flange nick.

 

[niconieuwoudt]

ramy123,

On a butt welded joint, the capping (called the weld reinforcement). This procedure I've described, might be on a weld neck flange or other butt welded joint in order to align the piping flange properly to the equipment flange for stress free and parallel bolt-up purposes

 

[heatexguy]

Why not use heat from a torch?

 

[niconieuwoudt]

heatexguy,

It is a violation against Client Procedures and Client rejected a waiver request to apply heat by flame/torch.

 

[qcrobert]

As long as your Client has accepted the repair welding and it does not violate any Jurisdictional laws then you should be ok to make the repair.

You should check with either the plantsite Owner's AI or your AI for concurrence.

 

[stanweld]

Beware of using this technique when PWHT is required or the pipe system is operating in the Creep regime.