Four Findings on the Same Joint

1. Preheat verified with a 150 deg F stick against a 200 deg F minimum. This is a false record. A stick that melts at 150 deg F proves only that the steel reached 150 deg F, which is 50 deg F below the minimum. Stop welding on that joint, measure properly, bring the full thickness to at least 200 deg F and re-mark. The welds already made on it need disposition.
2. Electrode exposure. At 10 a.m. the rods are out about 3.5 hours against a 4 hour limit. Not yet a violation, but one coffee break away from one. Write the removal time (10:30) on the quiver, return the rods to the oven for redrying per the WPS, and reissue from the oven. Never top up a quiver with fresh rods without noting it.
3. Interpass read with an IR gun on mill scale. Infrared reads surface and reads low on low-emissivity scale, so 390 deg F could be hiding a joint over the 450 deg F limit or well under it. Require contact thermocouple or a Tempilstik appropriate to the maximum, and re-measure before the next pass.
4. Tags signed by someone using the wrong instrument. This is record integrity rather than weld quality: withdraw the tags and replace them with a genuine measurement record signed by an authorized person.

You cannot accept them on the tag, and you cannot condemn them on the tag either. Establish facts first: which joint, which passes, actual preheat if it can still be measured, heating method and setpoint, ambient, thickness, and time since welding.

• If the joint can be shown to have been at or above 200 deg F (heater settings with monitoring, a second instrument, a supervisor's own measurement), document it and accept. The tag was wrong; the joint may be fine.
• If it cannot be shown, treat the welds as made outside the qualified preheat. On 1 in A572 Gr 50 with E7018, low preheat raises hydrogen-assisted cracking risk in the HAZ.

Dispositions in order of preference: (a) remove and re-weld with verified preheat; (b) leave in place subject to additional examination, magnetic particle or ultrasonic, performed after a delay of at least 24 to 48 hours so that delayed cracking has had time to open, with written acceptance by the engineer.

A same-day visual inspection proves nothing about delayed cracking. Hold production on that joint until the preheat verification method is corrected.

• Preheat: specify the instrument against the requirement. For a 200 deg F minimum, use a stick rated at or just above 200 deg F, never below. Measure at four points minimum, both sides of the joint, after soak. Record temperature, time and the name of the person who measured on the traveler.
• Interpass: contact measurement, taken at the point where the next pass starts and at the hottest point of the joint, before every pass. Record the maximum.
• Electrodes: oven at the WPS temperature with the recorder chart retained; quivers signed out and in with times; anything out more than four hours goes back for redrying per the WPS and manufacturer, never back in the quiver.
• Filler control: only opened, dry, correctly classified electrodes; issued count against returned count at the end of shift.
• Authority: helpers and apprentices may take temperatures only after training and written authorization to sign for it. A tag signed by someone using an out-of-range stick has no value at all.
• Surveillance: spot-check one joint per crew per shift against these controls and log the check. Trends matter more than any single check.