| Material and Casting Quality | Body material, cover material, screen material, casting grade, corrosion allowance, and material traceability. | Material grades must match the purchase specification. Common reference standards include ASTM A126 for gray iron pressure-retaining castings and EN 1561 for grey cast iron. | Material certificates, heat or melt records, casting inspection reports, and approved drawings. | 20% | High |
| Pressure and Leakage Testing | Shell-test pressure, seat or closure-test pressure, test medium, holding time, and acceptance criteria. | The supplier should provide a documented test procedure based on the applicable project standard, such as EN 12266-1 or API 598 where specified by the buyer. | Factory test reports, calibrated-gauge records, test procedures, and sample test videos when required. | 18% | High |
| Design and Connection Compliance | Strainer type, flow direction, end connection, face-to-face dimension, pressure class, drain arrangement, and screen-removal method. | Dimensions and flanges must comply with the selected standard. Relevant references may include ASME B16.1 for cast-iron flanges or EN 1092-2 for cast-iron flanges. | Dimension drawings, 2D or 3D CAD files, pressure-rating charts, and connection-standard declarations. | 15% | High |
| Filtration Performance | Screen material, mesh opening, open-area ratio, removable-screen design, pressure-drop data, and cleaning access. | The screen opening and filtration rating must be clearly stated and verified against the application. The supplier should provide pressure-drop data for the specified flow rate where required. | Screen drawings, mesh certificates, flow-test data, and application-specific sizing calculations. | 14% | High |
| Quality Management System | Quality-system certification, incoming inspection, process controls, final inspection, nonconformance handling, and calibration management. | A valid ISO 9001 certificate issued for the relevant manufacturing site is preferred. The certificate scope and validity should be independently checked. | Certification document, certificate verification record, inspection plan, calibration list, and corrective-action samples. | 12% | High |
| Production Capability | Foundry capacity, machining equipment, pattern-making capability, production lead time, monthly output, and subcontracting controls. | The supplier should demonstrate control of casting, machining, assembly, coating, and final testing. Outsourced processes must be identified and controlled. | Factory audit, equipment list, process flow chart, production photos, capacity statement, and sample purchase-order records. | 9% | Medium |
| Documentation and Traceability | Product drawings, bill of materials, inspection reports, packing list, certificate of conformity, and material documentation. | Each shipment should be traceable to the purchase order, product model, material batch, inspection result, and quantity supplied. | Sample quality dossier, serial or batch-number system, inspection checklist, and document-control procedure. | 7% | Medium |
| Commercial and Export Reliability | Quotation completeness, payment terms, packaging method, export experience, response time, warranty terms, and after-sales support. | The quotation should identify specifications, inclusions, delivery terms, packaging, inspection arrangements, warranty coverage, and spare-screen availability. | Formal quotation, proforma invoice, packaging specification, warranty policy, reference-project evidence, and communication records. | 5% | Medium |