Fastener Quality Control: 7-Point Inspection Checklist Before Shipment
From wire rod traceability to salt-spray hours — the checklist our QC team runs on every fastener batch.
Fasteners look like commodities until a batch fails in the field. These seven checks catch 95% of quality escapes before the container leaves the port.
1. Wire rod traceability: every heat number must map to a mill certificate. 2. Dimensional sampling: thread gauge go/no-go on 32 pcs per size per batch. 3. Hardness: HRC verification against the declared property class — an 8.8 bolt that reads HRC 35+ was quenched wrong and will snap.
4. Coating thickness: X-ray fluorescence on zinc plating, minimum 5μm for indoor, 8μm+ for outdoor use. 5. Salt spray: 72h for standard zinc, 500h+ for Dacromet/Geomet — ask for the lab photos, not just the number.
6. Torque-tension testing on a sample of 10: friction coefficient drift outside 0.10–0.16 causes assembly-line rework for your customer. 7. Packaging drop test: a carton that bursts at 80cm will not survive transloading in Rotterdam.
We publish per-batch inspection reports with photos to every buyer. If your current supplier can't, that's a conversation worth having.
Send your requirements — FOB/CIF quote within 24 hours.
