S-91251A731 1/2"-13 x 4 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 in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish extends service life in harsh industrial environments, minimizing maintenance needs.
• Precise Class 3A thread fit provides tight, secure connections with reduced vibration loosening for enhanced assembly integrity.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use and disassembly.
• Partially threaded design allows for optimal clamping force distribution, ideal for applications requiring precise grip length.
• Coarse UNRC threading enables quick installation and removal, saving time in assembly and maintenance operations.
• Hex socket drive compatibility with 3/8" tools ensures easy access in confined spaces and secure torque application.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in heavy-duty industrial settings, such as machinery assembly, automotive systems, and structural frameworks. The ASTM A574 compliant material, combined with a Class 3A thread fit and coarse UNRC threading, delivers superior vibration resistance and load-bearing capacity, preventing joint failure under dynamic stresses. The black-oxide surface treatment enhances corrosion protection in humid or chemically aggressive environments, while the partially threaded configuration allows engineers to optimize clamping force without compromising strength. Ideal for applications requiring high tensile strength and durability, this fastener ensures long-term reliability in demanding operations, from manufacturing equipment to construction projects.

Specification Summary & Compliance

This socket head cap screw adheres to precise dimensional standards, including Class 3A thread fit for tight tolerances and UNRC coarse threading with a 1/2"-13 size. It meets ASTM A574 specifications for material quality and performance, and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory adherence for industrial use.