| Material Grade | Food-contact stainless steel should normally be declared as AISI 304/EN 1.4301 or an equivalent grade. AISI 316/EN 1.4401 offers higher molybdenum content for improved chloride resistance. | Request the material specification, mill certificate, and random third-party material identification testing. | 15% | ____ |
| Bowl Thickness | For residential double sinks, a declared thickness of approximately 1.0–1.5 mm is commonly used. Confirm whether the stated thickness applies to the actual bowl rather than only the rim or sound-deadening pad. | Check technical drawings, production samples, and multiple measurement points using a calibrated thickness gauge. | 12% | ____ |
| Dimensions and Tolerances | Key dimensions include overall length, width, depth, bowl size, divider height, corner radius, drain opening, and cabinet cut-out. Production tolerances should be documented rather than described only as “standard.” | Approve a dimensioned drawing and inspect pre-production and mass-production samples against the drawing. | 10% | ____ |
| Welding and Seam Quality | Welds should be continuous where required, fully blended, free from visible pinholes and cracks, and resistant to staining after proper finishing and passivation. | Use visual inspection, dye-penetrant testing where appropriate, and a water-leak test for every approved production batch. | 12% | ____ |
| Surface Finish | Common finishes include brushed, satin, polished, and PVD-coated surfaces. The finish should be uniform, free from deep scratches, discoloration, burrs, visible dents, and inconsistent grain direction. | Compare the approved golden sample with random cartons under consistent lighting and inspect the entire visible surface. | 10% | ____ |
| Drainage Performance | The two bowls should drain without persistent water pooling. Drain position, bowl slope, overflow design, and compatibility with the selected waste kit directly affect performance. | Conduct a practical drainage test with both bowls, checking residual water and flow around the drain area. | 8% | ____ |
| Accessories and Compatibility | Confirm the included waste strainers, clips, seals, overflow parts, templates, and installation instructions. Drain-hole size and waste-kit dimensions must match the destination market. | Review the packing list, installation manual, technical drawings, and a complete assembled accessory set. | 7% | ____ |
| Quality Management | A documented quality system should cover incoming material inspection, forming, welding, polishing, leak testing, final inspection, traceability, and corrective actions. | Request current quality certificates, inspection records, process-control plans, and sample nonconformity reports with corrective actions. | 10% | ____ |
| Production Capacity and Lead Time | Evaluate documented monthly capacity, tooling availability, production scheduling, peak-season planning, and standard lead time for samples and repeat orders. | Verify capacity during a factory audit and compare quoted lead times with recent production and shipping records. | 6% | ____ |
| Packaging and Export Readiness | Packaging should protect the rim, corners, surface, drain fittings, and accessories during container handling. Carton markings and shipping documents should match the purchase order. | Perform a packaging drop or transport simulation where appropriate and inspect packed samples before shipment. | 5% | ____ |
| Commercial Terms and After-Sales Support | Compare total landed cost, minimum order quantity, tooling charges, payment terms, warranty period, replacement policy, response time, and spare-parts availability. | Obtain a written quotation and warranty policy, then verify response quality through pre-order technical communication. | 5% | ____ |
