S-91257A996 1"-14 x 9" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 150,000 psi ensures reliable performance in the most demanding heavy-duty applications
• Superior corrosion resistance with zinc yellow-chromate plating protects against harsh environmental conditions
• Precision extra fine threading (1"-14 UNS) provides superior vibration resistance and secure fastening
• Rockwell C33 hardness rating delivers excellent durability and wear resistance for long service life
• Partial threading design allows for optimal clamp load distribution and reduced stress concentration
• Class 2A thread fit ensures smooth assembly and consistent performance across applications
• Full regulatory compliance with ASME B18.2.1, SAE J429, RoHS 3, and REACH standards guarantees quality and safety

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers exceptional engineering value for heavy-duty industrial applications where vibration resistance and structural integrity are critical. The extra fine thread pitch (1"-14 UNS) provides superior holding power in materials prone to stress relaxation, while the partial threading design concentrates clamping force where it's needed most. The zinc yellow-chromate plated steel construction offers outstanding corrosion protection in challenging environments, from manufacturing facilities to outdoor equipment. With its external hex drive and substantial 1 1/2" head width, this fastener enables high-torque installation without stripping, making it ideal for structural assemblies, heavy machinery, and high-stress connections where failure is not an option.

Specification Summary & Compliance

This high-performance hex head screw features precise Class 2A thread fit tolerances with 1"-14 extra fine UNS threading and 2 1/2" minimum thread length. Manufactured to exacting ASME B18.2.1 and SAE J429 Grade 8 specifications, it delivers consistent quality and performance. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets while maintaining the 150,000 psi tensile strength and Rockwell C33 hardness required for the most demanding industrial applications.