Automotive nut cold heading die

* High-grade powder metallurgy steel + AlCrN PVD coating – specially formulated for automotive boron/alloy steels (grade 10/12), resists galling and fatigue. * Precision hex/flange cavity geometry – ensures exact across-flats and concentricity to bore, critical for subsequent tapping and wheel nut fitment. * Optimized taper and venting grooves – guarantees smooth part ejection at high stroke rates, eliminates sticking and surface pick-up. * Superior compressive strength (HRC 58–60, compressive yield > 4,500 N/mm²) – withstands heading loads up to 250 t without plastic deformation, maintaining critical thread-pilot diameters. * Mirror-finished internal contour (Ra ? 0.08 µm) – prevents metal adhesion, ensures bright, scuff-free inner walls across millions of cycles. * Designed for multi-station nut formers – proven stable at 250+ strokes/min, scrap rate <0.3% in mass automotive production. * Customizable bore diameters and hex sizes – adaptable to M4–M24 automotive series (DIN/ISO/SAE standards) and various flange profiles. * Optional DLC or duplex coating – extends die life by 50-100% under poor lubrication or high-silicon steel conditions. * 100% ultrasonic inspection + CMM dimensional check – guarantees zero internal micro-cracks, meeting automotive industry zero-defect requirements. * Interchangeable cartridge design – quick replacement without adjusting header timing, reducing downtime by 40%.