S-91251A612 1 1/2"-12 x 8" 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.
• Corrosion-resistant black-oxide coating extends service life by protecting against rust and environmental degradation in harsh conditions.
• Fine UNRF thread design provides superior vibration resistance and secure fastening in precision assemblies.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining thread integrity and drive performance over repeated use.
• Partially threaded shank allows for precise clamping force control and reduces stress concentration in connected materials.
• Class 2A thread fit ensures easy assembly and consistent engagement with standard nuts and tapped holes, saving installation time.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety for global supply chain requirements.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to address critical challenges in heavy machinery, automotive, and construction sectors where vibration loosening and corrosion are common failures. The fine UNRF thread enhances grip in soft or brittle materials, while the 1 1/2"-12 thread size and 8" length provide ample engagement for thick assemblies. The hex drive design allows high torque application in confined spaces, ensuring secure fastening in structural frames, engine components, and industrial equipment. Its black-oxide surface treatment not only resists moisture and chemicals but also reduces galling during installation, prolonging tool life and maintenance cycles. Ideal for high-strength bolting applications, this screw delivers consistent performance under dynamic loads, minimizing downtime and replacement costs.

Specification Summary & Compliance

This socket head cap screw features a 1 1/2"-12 UNRF fine thread with Class 2A thread fit for precise dimensional accuracy per inch system standards. It is manufactured from alloy steel under ASTM A574 specifications, ensuring consistent mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances for safe industrial use.