luna@lunaele.com
- Incoming control (IQC – on material received) Inspection points
Raw material identity & certificates: copper alloy grade, surface treatment/materiel specs. Coating verification (tin/silver/nickel plating type): thickness / coverage (as applicable). Dimensional check of terminal parts: critical dimensions linked to crimp barrel and mating interface. Packaging & moisture/protection: ESD-safe, anti-corrosion bags, shelf-life labeling. Sampling rule
Use AQL-based sampling (e.g., AQL levels defined per defect type: critical/major/minor). Full inspection for traceability-critical items (e.g., part number match, coating certificate match); otherwise sampling per AQL. 2) Process control (IPQC – during manufacturing/assembly) Inspection points (by operation)
Process parameter verification: stamping/forming parameters (die alignment, burr control) plating bath controls (if applicable) crimp tooling setup (die position, cycle count, wear condition) In-process crimp verification (for terminal-crimping customers): conductor crimp height/width within tolerance (use gauges) insulation crimp coverage and strain relief integrity check for wire strand cut, exposed strands, loose insulation capture Electrical/contact reliability monitoring (if your process includes validation steps): initial resistance trend checks (statistical monitoring) Visual and dimensional SPC: frequent checks of key dimensions of the crimp barrel and contact area maintain CPK/SPC on most critical CTQs Sampling rule
For CTQs (critical-to-quality), use 100% in-line checks where feasible (especially when crimp tooling is automated). Otherwise apply frequency-based checks (e.g., every X lots or every X pcs). Use run-at-rate sampling plus triggered audits when drift is detected (based on control charts). 3) Final inspection (OQC – end of line / before shipment) Inspection points
Final dimensional conformance (again focusing on CTQs). Pull-out strength / withdrawal resistance: meet spec limits with defined test method. Visual acceptance: no loose crimp, no deformation beyond limit, no excessive burrs, no damage to plating. Electrical test (if required): contact resistance or continuity test per customer requirement. Traceability & documentation: batch/lot number, heat/coil/plating lot ID, test results record COA/COC/inspection report completion Sampling rule
AQL sampling for packaged goods; use higher scrutiny for critical defects. If a lot fails: implement 100% sort on that lot after root-cause containment. 4) Overall control system Control plan defining CTQs, methods, frequency, acceptance criteria, and responsible roles. SPC/CPK monitoring on crimp height, insulation retention, and pull-out strength (or equivalent CTQs). Tooling wear management: scheduled die inspection/replacement, calibration verification. Lot traceability: link each shipped lot to incoming materials and in-process parameter records. Corrective action: immediate containment + 8D/RCFA when abnormal trends occur. If you tell me your terminal type (e.g., insulated crimp terminal, blade/F tabs, pin/socket) and whether you are doing crimping in-house or shipping terminals only, I can tailor the inspection points and sampling plan more precisely.
