Dear All Members,

Good day Sir, could I ask one question?. I have done a nozzle opening on complete vessel. After discussed with my client, nozzle to be relocate. Could I patch that hole using plate or need to cut and replace with new plate?. Any part in ASME allow to patch a hole?.

Sir, could you advice us regarding this matter?.

Kindly, your prompt respond are appreciated.

Thank you.

Best regards,

Faizol.

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Faizol
(PV-elite User)

I have experienced similar situation before two times. First was in main shell and other was in hemispherical dish end. Both times cut off material was rewelded with proper weld edge preparation followed by 100% RT. Designer concurrence has to be taken and joint will be categorized as A. Same has to be included in as built drawing by giving proper seam number in weld map. NCR is required and its disposition should be similar as specified in your ASME Quality Control Manual.

I will prefer that the same hole should be provided nozzle with blind flange provided there is no obstruction at site. What is the diameter of the hole and thickness? What is the grade of material? It is better that you provide more information.

[quote="faizol"]Dear All Members,

Good day Sir, could I ask one question?. I have done a nozzle opening on complete vessel. After discussed with my client, nozzle to be relocate. Could I patch that hole using plate or need to cut and replace with new plate?. Any part in ASME allow to patch a hole?.

Sir, could you advice us regarding this matter?.

Kindly, your prompt respond are appreciated.

Thank you.

Best regards,

Faizol.[/quote]

See UW-34 and in this forum Sect. VIII Div.1: "Spin holes"
mauro

Mauro, I would be reluctant to compare such a patch to an axisymmetrical spin hole in a dished head- a pipe patch is stressed in a non-homogenous way! This results in shear rather than pure tension in case of any irregularities. I think this weld has to be categorized as A with all consequencies. And I would use the cut-out to plug it back to reduce any stress concentrations due to possible dissimilar thicknesses/properties.

Faizol, don't forget to maintain out-of-roundness!

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Konrad Anikiel