S-91257A854 3/4"-10 x 4 3/4" 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, minimizing failure risks.
• Superior corrosion resistance from zinc yellow-chromate plating extends service life in harsh industrial environments, reducing maintenance and replacement frequency.
• High hardness rating (Rockwell C33) provides excellent wear resistance and durability, maintaining fastener integrity under high stress.
• Coarse UNC threading offers faster installation and better debris clearance, ideal for quick assembly in rugged conditions.
• Partially threaded design allows for precise clamping force control, preventing joint loosening in vibrating machinery.
• External hex drive and hex head enable easy installation with standard tools, improving workflow efficiency on the job site.
• Compliance with ASME B18.2.1 and SAE J429 standards guarantees consistent quality, dimensional accuracy, and interchangeability for engineering projects.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address critical challenges in heavy-duty industrial applications, such as construction machinery, agricultural equipment, and structural assemblies. The steel material combined with zinc yellow-chromate plating provides a robust barrier against corrosion, essential for outdoor or high-moisture environments. Its UNC coarse thread and Class 2A thread fit ensure secure fastening even in materials prone to wear, while the partially threaded section concentrates stress appropriately to prevent shear failure. By meeting ASME B18.2.1 and SAE J429 specifications, it delivers predictable performance, reducing downtime and enhancing safety in engineering systems requiring high tensile strength and reliability.

Specification Summary & Compliance

This fastener features a 3/4"-10 UNC coarse thread with Class 2A dimensional tolerance for consistent fit. It complies with ASME B18.2.1 and SAE J429 standards, ensuring adherence to manufacturing and material requirements. The product is manufactured from steel and includes zinc yellow-chromate plating for corrosion protection, supporting compliance with common industry regulations for safety and performance.