Reading a Weld Symbol on a Structural Drawing
A drawing for a steel bracket shows a fillet weld symbol on the arrow side with a 6 mm leg, a length of 150 mm, a pitch of 200 mm, and a tail note reading 'WPS 04, PWHT not required'. A second symbol on the same joint is on the other side of the reference line with a 5 mm leg and a length of 75 mm. The fabrication note says 'all welds continuous unless otherwise shown'. The client's inspector says the intermittent weld is not acceptable because the note requires continuous welds. The drawing revision is B, and you have revision A on the bench.
1. Interpret what the two symbols require and resolve the conflict with the general note.
Read the worked answer
The arrow-side symbol is a fillet weld, 6 mm leg, 150 mm long, repeated at a 200 mm pitch, so it is an intermittent weld with a 50 mm gap between segments. The other-side symbol is a 5 mm fillet, 75 mm long, which is a separate weld on the opposite face. The tail note ties the joint to WPS 04 and confirms post-weld heat treatment is not required.
The general note 'all welds continuous unless otherwise shown' is overridden by the specific symbol, because a dimensioned symbol is more specific than a general note. The intermittent weld is shown, so it is not covered by the default. The inspector's reading is understandable but incorrect on the drawing as written. The correct action is to confirm with the designer or document controller that revision B is current and that the intermittent weld is intended, and to record that confirmation. Do not simply weld continuously to satisfy the inspector without a documented change, because that changes the design and the WPS.
2. What would you do about the revision A drawing on the bench, and what checks would you make before welding?
Read the worked answer
Remove revision A from the work area and replace it with revision B, or mark it superseded and return it to document control. Welding to a superseded drawing is a common source of nonconforming work. Before welding, check that the revision on the drawing matches the revision on the work order, confirm the WPS number and that its qualified range covers 6 mm and 5 mm fillets on this material and thickness, and confirm the welder is qualified for the position and process. Check the joint preparation matches the drawing, and confirm the intermittent weld length and pitch with a tape before welding. Record the revision used on the inspection record. If there is any doubt about which revision applies, stop and ask rather than guess.