Q. Requirements for vessels with thickness?

The following additional requirements are applicable, as specified,  to Carbon Steel and Low Alloy steel pressure vessels with main shell thicknesses greater than 50.8 mm:

• Prior to release from the supplier, all plate materials shall be Ultrasonically Examined (UT) in accordance with SA-435 or SA-578.
• The carbon content for Carbon Steel plates and forgings shall be limited to 0.30% max.
• All vessel connections shall be flanged.
• All nozzles shall be of the integrally forged, self-reinforcing type.
• Reinforcing pads for opening reinforcement are not permitted.
• Nozzle internal projections shall be flush with the contour of the vessel.
• 100% radiography (RT) shall be carried out on all category A, B, and C butt welds.
• Radiography shall be carried out after PWHT.
• 100% UT shall be carried out on all forgings over 75 mm in thickness.
• 100% UT shall be carried out on all category D welds.
• 100% Magnetic particle examination (MT) shall be carried out on all cut edges of pressure containing parts including all nozzle openings.
• 100% MT shall be carried out after PWHT on all areas from which temporary attachment welds have been removed.