Night-Shift Lead Bypasses Preheat and the Crew Follows Him
Your shop runs two shifts and 22 welders. Ray, the night-shift lead, has 25 years of experience, high output, and a strong following among the crew. The job is 1 in. A572 Grade 50 groove welds with a qualified WPS requiring 150 F minimum preheat and a 260 A maximum. In July, Ray skipped preheat documentation on 12 joints and ran about 300 A because, he says, the steel was warm from the sun and the higher current finishes faster. Ultrasonic testing found three cracks in those 12 joints. The customer audit is next week. Ray told you privately that he has done it this way for years and has never had a failure. The crew says the day-shift supervisor is just trying to hit him with paperwork. Your plant manager wants the audit to go smoothly and production to stay on schedule.
1. How do you handle the first conversation with Ray?
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Plan a private, fact-based conversation, not a public challenge. Bring the WPS, the ultrasonic reports, and the preheat records. Open with the specific gap: three cracked welds and no documented preheat on the night shift. Ask Ray to walk through what happened and why. Listen for a real constraint: maybe the preheat blankets were locked up, the temperature indicators were missing, or the WPS is impractical for the fit-up. Then restate the standard: the WPS is the contract, not a suggestion. If he believes the WPS is wrong, he can challenge it through engineering, not bypass it. Separate the behavior from his 25-year record. Set clear expectations and consequences, and document the conversation. Do not promise to hide it from the customer. The goal is to find out whether this is a logistics failure, a habit, or a test of authority.
2. What quality containment do you put in place before the audit?
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Treat all night-shift welds on that joint as suspect until inspected. Quarantine the affected parts, perform ultrasonic or magnetic particle testing as directed by the engineer, and repair per an approved repair WPS. Issue a nonconformance report. Notify the customer auditor before the audit with the facts and the corrective action plan; hiding it is worse than the defect. Review the last 30 days of preheat logs, gas records, and WPS adherence for the night shift to see whether the shortcut was isolated. Verify that the WPS is feasible on nights: are blankets, controllers, temperature-indicating crayons, and sufficient time available? If not, fix the logistics before disciplining the behavior. Assign a second check, such as night-shift QA sign-off on preheat before welding.
3. What long-term supervisory actions do you take to prevent recurrence without destroying Ray's influence?
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Use Ray as part of the solution rather than making him a martyr. Ask him to lead a night-shift toolbox talk on why preheat matters on that steel and to help audit the next week's joints. But hold the line: retraining, a written warning, and a follow-up audit with clear consequences if it recurs. Review incentive pay; if the bonus rewards feet and not first-pass yield, it is driving the behavior. Add a second check on preheat and current before welding. Track leading indicators such as preheat compliance and WPS parameter checks, not just defect rates. Meet with the crew and explain that the standard applies to everyone, including the lead. The goal is not to win the argument; it is to make the right method the easy method and to show that experience is valued when it supports the procedure.