| 1 | Material Traceability | The supplier should identify stainless steel grade, heat number, thickness, finish, and supplier source for each production lot. | Material certificates should conform to the specified grade, such as ASTM A240/A240M for stainless steel plate and sheet where applicable. | Mill test certificate, incoming inspection record, lot-control procedure, and sample traceability report. | Incorrect alloy, mixed lots, corrosion, and inconsistent mechanical properties. |
| 2 | Press and Tooling Capability | Available presses, dies, feeders, and forming methods must match the material thickness, part geometry, tolerance, and production volume. | The equipment list should show suitable tonnage, bed size, stroke, speed, and progressive or compound-die capability for the target part. | Equipment list, press specifications, tooling photographs, die-maintenance records, and sample parts. | Cracking, springback, premature die wear, and unstable production output. |
| 3 | Dimensional Control | Critical dimensions and geometric tolerances must be measured using calibrated instruments and documented inspection plans. | Use a control plan with defined sampling frequency, measurement method, nominal value, tolerance, and reaction plan for out-of-specification results. | First Article Inspection report, control plan, gauge list, calibration certificates, and capability study. | Fit problems, assembly interference, leakage, and customer rejection. |
| 4 | Quality Management System | A documented quality system should control purchasing, production, inspection, nonconformities, corrective actions, and document retention. | ISO 9001 certification is a useful baseline; IATF 16949 may be required for automotive supply chains. | Valid certificate, certification scope, latest audit result, corrective-action records, and quality manual index. | Uncontrolled processes, recurring defects, and weak corrective action. |
| 5 | Surface Finish and Corrosion Protection | The supplier must control scratching, burrs, discoloration, contamination, passivation, cleaning, and any required secondary finish. | Surface requirements should be defined by measurable finish specifications, approved visual standards, and applicable passivation or cleaning procedures. | Surface standard, approved samples, passivation records, cleanliness test results, and packaging specification. | Cosmetic defects, corrosion, contamination, and premature field failure. |
| 6 | Process Capability and SPC | Critical characteristics should be monitored through statistical process control rather than final inspection alone. | For stable, normally distributed critical dimensions, many projects use Cpk ≥ 1.33 as an internal target; the customer specification takes priority. | Control charts, capability studies, process-risk analysis, and documented reaction plans. | Process drift, excessive variation, and hidden production instability. |
| 7 | Prototype and Tooling Development | The manufacturer should be able to review drawings, identify forming risks, design or manage dies, and validate samples before mass production. | A clear design-review process should cover material flow, bend radius, burr direction, springback, datum strategy, and tool-maintenance planning. | Design-for-manufacturing review, tooling schedule, trial reports, sample approval records, and change-control procedure. | Late tooling changes, prototype delays, and repeated sampling cycles. |
| 8 | Compliance and Environmental Controls | Products and processes should meet the destination market’s substance, safety, environmental, and waste-management requirements. | Where applicable, verify RoHS Directive 2011/65/EU, REACH Regulation (EC) No. 1907/2006, and ISO 14001 environmental-management certification. | Material declaration, restricted-substance statement, environmental certificate, chemical inventory, and waste records. | Import restrictions, regulatory non-compliance, and customer approval delays. |
| 9 | Capacity, Lead Time, and Delivery Reliability | Production planning should demonstrate sufficient machine availability, labor coverage, raw-material supply, and backup capacity. | Evaluate quoted tooling time, sampling time, mass-production lead time, minimum order quantity, and historical on-time-delivery performance. | Capacity-loading report, production schedule, on-time-delivery data, inventory policy, and business-continuity plan. | Missed launch dates, supply interruptions, and expedited freight costs. |
| 10 | Commercial Transparency and After-Sales Support | The quotation should clearly separate material, tooling, processing, finishing, packaging, freight, inspection, and engineering costs. | The supplier should provide a defined response time for quality issues, engineering changes, corrective actions, and replacement or rework decisions. | Itemized quotation, payment terms, warranty terms, escalation contacts, corrective-action template, and change-order policy. | Unexpected costs, communication gaps, unresolved defects, and ownership disputes. |