Based on our field experience across Singapore lines, torque-related rejects almost always trace back to one of three root causes. In short, fix these three and your reject rate on fastener-driven defects typically drops by 60-90%.
The three primary causes of torque rejects
- Uncalibrated tools. Tools drift out of tolerance without anyone noticing. For example, a torque wrench that was accurate six months ago may now sit 10-15% out. As a result, nobody catches it until a batch of parts gets rejected.
- Operator error. Common mistakes include missed fasteners, re-hitting joints, or applying torque in the wrong sequence. Without clear error-proofing, even skilled operators make these mistakes under time pressure.
- Wrong tool selection. A tool used outside its effective range gives poor repeatability. For example, a 10-100 Nm wrench on a 15 Nm joint delivers inconsistent results.
How to eliminate torque-related rejects
First, calibrate every torque tool on a fixed schedule. We recommend 6 or 12 months. Next, use Mountz cam-over or click-type wrenches on critical joints. Therefore, your tool stops at the preset torque every time. In addition, train operators on joint sequence and re-strike rules.
Above all, log critical events. A data-logging driver records every fastener with timestamp and torque value. As a result, you have an audit trail that satisfies ISO 6789 and ISO 13485 requirements.
Quick checklist to cut rejects this quarter
- Verify every torque tool against a calibrated reference each shift.
- Match tool range to joint torque, with the joint near the mid-range.
- Use cam-over tools where over-torque risk is high.
- Log critical events for traceability.
- Review reject data weekly to spot drift early.
Want a tool review for your line? Contact Phil Industries or WhatsApp our engineer at +65 98539030.