S-91251A733 1/2"-13 x 5 1/4" 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 industrial applications, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish protects against rust and extends service life in harsh environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies with minimal backlash.
• High hardness rating (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use.
• 3/8" hex drive design allows for easy installation and high torque application with standard tools, improving assembly efficiency.
• Partially threaded shank enables optimal clamping force distribution, ideal for applications requiring precise joint control.
• Coarse UNRC threads facilitate quicker installation and better performance in materials prone to stripping or cross-threading.

Professional Applications & Engineering Value

Engineered for demanding industrial environments, this black-oxide alloy steel socket head cap screw delivers exceptional reliability in heavy machinery, automotive assemblies, and construction equipment where vibration resistance and high tensile strength are critical. The combination of Class 3A thread fit and coarse UNRC threads ensures secure fastening in soft materials or applications requiring frequent disassembly. The partial threading design provides superior clamp load distribution, preventing joint loosening under dynamic loads. With its 3/8" hex drive and standardized socket head profile, it enables efficient installation in confined spaces while maintaining compatibility with common industrial tools, significantly reducing assembly time and maintenance costs.

Specification Summary & Compliance

This socket head cap screw features precision Class 3A thread fit with 1/2"-13 UNRC coarse threads and partial threading configuration. Manufactured to ASTM A574 specifications, it ensures consistent quality and performance in industrial applications. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, guaranteeing safe use across various industries while meeting rigorous international regulatory requirements.