| 1 | Material Grade and Traceability | Steel grade, heat number, mill certificate, chemical composition, and lot-to-lot traceability. | Verify the material certificate against the purchase specification and the applicable bar-steel standard, such as ASTM A29/A29M or an equivalent national standard. | 15% | 0–5 |
| 2 | Dimensional Accuracy | Measured diameter, length, straightness, runout, chamfer, and tolerance results for finished shafts. | Check inspection records using calibrated micrometers, gauges, and coordinate-measuring equipment. Specify ISO 286 limits and fits where applicable. | 15% | 0–5 |
| 3 | Surface Finish | Surface roughness value, visual inspection results, grinding marks, scratches, pits, and surface defects. | Request Ra measurements and confirm the evaluation method under ISO 21920. Define the required Ra value on the technical drawing. | 10% | 0–5 |
| 4 | Heat Treatment Capability | Available processes, furnace records, hardness results, case depth where applicable, and distortion-control procedures. | Verify hardness using Rockwell methods described in ISO 6508 and compare results with the approved drawing or purchase specification. | 12% | 0–5 |
| 5 | Mechanical Performance | Tensile strength, yield strength, elongation, hardness, and test direction for representative production lots. | Review laboratory reports based on ISO 6892-1 for tensile testing or the test method specified in the purchase agreement. | 12% | 0–5 |
| 6 | Machining and Process Control | Equipment list, CNC turning capacity, grinding capability, process flow, first-article inspection, and in-process controls. | Audit the documented process flow and compare actual equipment capability with shaft diameter, length, tolerance, and geometry requirements. | 10% | 0–5 |
| 7 | Quality Management System | Valid certificate, scope of certification, corrective-action records, calibration system, and nonconformance procedure. | Confirm the certificate scope and validity through the issuing certification body. ISO 9001 is a commonly used quality-management reference. | 8% | 0–5 |
| 8 | Inspection Documentation | Inspection plan, dimensional report, material certificate, hardness report, final inspection report, and certificate of conformity. | For metallic products, request the documentation level stated in the order; EN 10204 defines common inspection-document types such as 2.1, 2.2, 3.1, and 3.2. | 6% | 0–5 |
| 9 | Production Capacity and Lead Time | Monthly capacity, current utilization, standard production lead time, sample lead time, and on-time delivery history. | Compare documented capacity with the required annual volume and verify delivery performance using purchase-order records or references. | 6% | 0–5 |
| 10 | Packaging, Corrosion Protection, and Logistics | Packaging specification, rust-prevention method, moisture protection, bundle weight, marking, export documents, and shipping terms. | Approve packaging through sample shipment testing and confirm that product identification remains legible throughout transport and storage. | 6% | 0–5 |
