S-91251A533 1/4"-20 x 1/4" ASTM A574 Alloy Steel Socket Head Screws
Alloy Steel Socket Head Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure in demanding applications.
- Superior corrosion resistance from the black-oxide finish extends service life in harsh industrial environments, minimizing maintenance and replacement costs.
- Precise Class 3A thread fit guarantees tight, secure fastening with minimal play, enhancing assembly accuracy and vibration resistance.
- Hex socket drive design allows for easy installation and removal in confined spaces, improving efficiency and reducing tool slippage.
- Rockwell C37 hardness provides excellent wear resistance and durability, ensuring long-term performance in repetitive or high-load scenarios.
- Full threading offers consistent engagement along the entire length, enabling flexible positioning and strong clamping force.
- Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety, meeting global regulatory standards for industrial use.
Professional Applications & Engineering Value
This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to address critical challenges in industrial settings, such as vibration loosening and corrosion-induced degradation. The UNC coarse thread and Class 3A fit provide superior holding power in metals and composites, reducing the need for frequent retightening in machinery, automotive, and heavy equipment assemblies. The alloy steel construction combined with a black-oxide surface treatment resists oxidation and wear, making it ideal for outdoor or humid environments. Its hex drive and fully threaded design facilitate quick installation in tight spaces, streamlining production lines and maintenance workflows while ensuring consistent, high-strength fastening.
Specification Summary & Compliance
This socket head cap screw features a 1/4"-20 UNC coarse thread with a Class 3A thread fit for precise dimensional accuracy. It meets ASTM A574 specifications for high-strength alloy steel fasteners and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity.
