Quality Control In Chain Making
| Raw Material Receiving Inspecion (steel bars and wires) |
Visual inspection (steel code, heat no.,
surface finish, quantiy, etc.) |
Dimensional check
(sample percentage) |
Mechanical property retest and chemical
composition check by samples per heat or batch |
Materials acceptance
and inventory login |
| Bar Cutting |
| Check size, heat no., cutting length design |
Cut length measurement |
Tagging of cut bars in bucket |
| Links Making (bending, welding, trimming and/or forming) |
| Welding parameters setting |
Electrode cleaning |
Welding records/curve check |
Trimming smoothness |
Sample links dimensional check |
| Heat-treatment |
| Quenching and tempering parameters setting |
Furnace calibration |
Temperature monitor |
Heat-treatment records/curves review |
| Manufacturing Force Testing to 100% Chains |
| Proof machine calibration |
Force setting per chain size and grade |
Loading of full chain with records |
| Links & Chains Dimensional Check |
| Caliper calibration |
Links measurement frequency |
Chain length / gauge length measurement with preset tension / force or hanged vertical |
Dimensional records |
Out-of-tolerance links marking and rework |
| Surface Finish Check and Grinding |
| Links surface visual inspecton for free of cracks, dents, overcut and other defects |
Repair by grinding |
Links determined unacceptable for replacement |
Records |
| Mechanical Property Tests
(breaking force , hardness , V-notch impact , bending , tensile , etc as applicable) |
| Breaking force test per applicable standard and client's specs |
Hardness test on link surface and/or cross section per standards and client's rules |
Other mechanical tests as required per chain type |
Test failure and retest, or chain failure determination per standards and client's rules |
Test records |
| Special Coating and Surface Finishing |
| Special coating fnish per client's specs, including painting, oiling, galvanization, etc. |
Coating thickness check |
Coating report |
| Packing and Tagging |
| Packing & tagging means per client's specs and applicable standards |
Packing material (barrel, pallet, bag, etc.) suitable for lifting, handling and sea transportation |
Photo records |
| Final Data Book and Certification |
| Per client's specs and order terms |
