ASME B18.3 Torx Countersunk Machine Screw

Product Parameter

Material & Raw-Material Inspection

All raw materials strictly comply with American fastener material standards. Carbon steel raw bars adopt high-purity low-carbon steel with stable tensile and hardness properties, avoiding brittle fracture during high-torque assembly. Stainless steel materials pass component inspection to ensure full corrosion resistance consistent with US industrial requirements. Each batch of raw materials is accompanied by material test reports (MTC), with sampling detection of tensile strength, yield strength and surface finish. Impure and substandard raw materials are completely eliminated to ensure every finished screw meets ASME B18.3 dimensional tolerance and mechanical performance standards, supporting long-term stable use of US-standard equipment projects.

Quality Control & Production Flow

Produced in full accordance with ASME B18.3 standard production procedures: raw material screening → precision cold heading forming of countersunk head → integral Torx recess stamping → unified UNC/UNF thread rolling → heat treatment strengthening → surface anti-rust treatment → full-size tolerance inspection → thread gauge detection → torque sampling test → finished product packaging. The Torx star groove is precisely formed with uniform depth and symmetrical lobe structure, effectively preventing tool slipping. Thread rolling ensures standard tooth pitch and complete tooth shape, achieving zero-gap matching with American standard nuts and threaded holes. Each batch undergoes salt spray test and fatigue resistance test to stabilize batch quality.

Technical Notes & Engineering Remarks

This product is a dedicated US standard fastener, only suitable for matching UNC/UNF unified thread systems, not compatible with metric thread holes to avoid assembly mismatch. The 100° countersunk head is designed for flush installation, effectively reducing surface protrusion and avoiding structural friction and interference of equipment. The Torx drive structure can bear 30% higher torque than cross recess screws, suitable for high-precision and high-tightness assembly requirements. For outdoor and coastal engineering projects, 316 stainless steel or hot-dip galvanized models are recommended to enhance salt spray and aging resistance. All dimensional tolerances follow ASME national standard grades to ensure interchangeability with imported original parts.

Order & Customization Description

Full range of US standard Torx countersunk machine screw sizes are in stock, supporting fast delivery for North American market orders and US-standard engineering projects. We support personalized customization of non-standard inch lengths, special thread specifications and enhanced anti-corrosion processes. Official standard compliance certificates, mechanical performance test reports and salt spray test reports can be provided for project bidding and acceptance. Support OEM laser marking and exclusive export packaging, with stable supply capacity for long-term batch orders from overseas agents and engineering customers.