S-91257A970 1"-8 x 6 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum Load-Bearing Capacity: With a tensile strength of 150,000 PSI and Rockwell C33 hardness, this screw provides exceptional resistance to shear and tensile forces, ensuring reliable performance in high-stress applications.
• Superior Corrosion Protection: The zinc yellow-chromate plating offers enhanced resistance to rust and environmental degradation, extending the fastener's service life in harsh industrial settings.
• Optimized Thread Design: UNC coarse threading and Class 2A thread fit enable faster installation and reduced risk of cross-threading, improving assembly efficiency and connection integrity.
• High-Strength Material Compliance: Manufactured from Grade 8 steel, this hex head screw meets stringent ASME B18.2.1 and SAE J429 standards, guaranteeing consistent quality and mechanical properties.
• Secure External Hex Drive: The external hex head design allows for high torque application with standard tools, preventing stripping and ensuring tight, vibration-resistant fastening.
• Versatile Partial Threading: The partially threaded shank provides unthreaded grip length for better clamp load distribution, ideal for materials requiring precise clamping force.
• Environmental and Regulatory Safety: Compliant with RoHS 3 and REACH regulations, ensuring the fastener is free from hazardous substances and safe for various industrial uses.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address critical challenges in heavy machinery, structural steel connections, and industrial equipment assembly. The 1"-8 UNC coarse thread with Class 2A fit ensures rapid installation and robust holding power, minimizing downtime in production environments. The zinc yellow-chromate plating significantly enhances corrosion resistance, making it suitable for outdoor or humid conditions where durability is paramount. With a 150,000 PSI tensile strength and partial threading, it effectively distributes clamp loads and resists vibrational loosening in applications such as construction frameworks, automotive chassis, and manufacturing fixtures. By adhering to ASME B18.2.1 and SAE J429 standards, it delivers consistent performance, reducing the risk of fastener failure and maintenance costs in demanding engineering projects.

Specification Summary & Compliance

This fastener features a 1"-8 UNC coarse thread with Class 2A thread fit for precise dimensional accuracy and easy assembly. It is manufactured in accordance with ASME B18.2.1 and SAE J429 specifications, ensuring reliable mechanical properties and interchangeability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety for industrial use without restricted substances.