Purchasing Advice Views: 13

Purchasing acceptance - how to inspect countersinks on delivery: 1) Check documents - delivery note, invoice, purchase order: supplier, name, spec, quantity, price consistent; 2) Count quantity - matches the order, no short or extra; 3) Verify specs - angle (angle gauge, within +/-0.5 deg), head diameter (micrometer, within +/-0.05mm), shank (h6 or h7), overall length, material (HSS/HSS-E/Carbide), coating (TiN gold/TiAlN violet-black/AlCrN dark gray/DLC black); 4) Visual inspection - smooth surface, no cracks, rust or knocks; coating even, no peeling or bubbles; edges sharp, no chipping, rolling or burrs; shank clean, no rust; 5) Dimensional accuracy - micrometer for diameters, indicator for runout (under 0.02mm), angle gauge for angles; 6) Material confirmation - check markings, request material certificates (spectrum analysis report); do not judge by price alone - cheap tools may be standard HSS sold as cobalt; 7) Edge inspection - magnifier: check every flute, no unevenness; 8) Hardness test - Rockwell: HSS HRC62-64, HSS-E HRC65-67; 9) Marking check - laser marking on the tool (brand, spec, material, batch), certificate and QC stamp in the packaging; 10) Keep records - file acceptance records; contact the supplier promptly on any issue; trial-cut the first piece to confirm machining quality before batch use.