S-91251A911 1"-8 x 1 3/4" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under extreme loads, reducing the risk of fastener failure in critical applications.
• Superior hardness (Rockwell C37) provides excellent wear resistance and durability, extending service life in high-stress environments.
• Precision Class 3A thread fit guarantees tight, secure fastening with minimal backlash, ideal for applications requiring high vibration resistance.
• Black-oxide coating on alloy steel offers enhanced corrosion resistance, protecting against rust and ensuring long-term reliability in harsh conditions.
• 3/4" hex drive design allows for high-torque installation with standard tools, enabling efficient assembly and maintenance operations.
• Fully threaded construction ensures consistent clamping force along the entire length, providing uniform load distribution.
• Compliance with ASTM A574, RoHS 3, and REACH assures material quality and environmental safety, meeting strict industrial and regulatory standards.

Professional Applications & Engineering Value

These socket head cap screws are engineered to solve critical fastening challenges in demanding industrial environments. The black-oxide alloy steel construction combined with Class 3A UNRC coarse threads delivers superior vibration resistance and fatigue strength, making them ideal for heavy machinery, automotive assemblies, and structural applications where loosening under dynamic loads is a concern. The 1"-8 coarse thread provides quick assembly and disassembly while maintaining strong holding power. With their high tensile strength and corrosion-resistant surface treatment, these fasteners eliminate common failure points in equipment subjected to extreme pressures and environmental exposure, ensuring extended service life and reduced maintenance costs.

Specification Summary & Compliance

This socket head cap screw features precision Class 3A thread fit with UNRC coarse thread specifications (1"-8 thread size). Manufacturing complies with ASTM A574 standards for alloy steel socket head cap screws, ensuring consistent quality and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for use in regulated industries and international markets.