Weld Profile Acceptance Criteria

Weld Reinforcement and Acceptance Criteria

• Weld reinforcement exceeding specified amounts in the weld reinforcement table is considered unacceptable.

Socket and Fillet Welds

• As-welded surfaces are permitted, but must be free from coarse ripples, grooves, overlaps, abrupt ridges, undercut, and valleys.
• The surface condition of finished welds must be suitable for non-destructive examinations.
• Fillet welds may vary from convex to concave.
• The size of a fillet weld is determined by the length of the largest inscribed right Isosceles triangle (equal leg) or the leg length of the largest right triangle (unequal leg).
• Theoretical throat of an equal leg fillet weld is 0.7 times the size.

Fillet Weld Profiles and Slip-On/Socket Welded Flanges

• Typical minimum fillet weld details for slip-on flanges and socket-welding components are provided in fillet weld diagrams.
• For slip-on and socket-welded flanges, X min. is 1.4 times T1 (minimum pipe wall thickness) or thickness of the hub, whichever is smaller, but not less than 1/8 in.

Weld Reinforcement Table (ASME B31.3)

• Thickness of reinforcement or internal weld protrusion depends on the thickness of the base material.
• External weld reinforcement and internal weld protrusion must be fused with and merged smoothly into the component surface.

Acceptance Criteria for Completed Welds (Butt Welds)

• As-welded surfaces are permitted, but must be free from coarse ripples, grooves, overlaps, abrupt ridges, undercut, and valleys.
• The surface condition of finished welds must be suitable for radiographic and other non-destructive examinations.
• Undercuts must not exceed 1/32 in. and shall not encroach on the minimum required section thickness.
• Concavity of the root surface must not reduce the total thickness of the joint, including reinforcement, to less than the nominal thickness of the thinner component being joined.
• Excess root penetration is limited to 1/8 in. or 25% of the nominal wall thickness of the thinner component being joined, down to ¼ in. wall thickness.