S-91251A501 2-56 x 1 1/8" ASTM A574 Alloy Steel Socket Head Screws
Alloy Steel Socket Head Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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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.
- Precise Class 3A thread fit provides superior engagement and vibration resistance, minimizing loosening in critical assemblies.
- Black-oxide coating on alloy steel offers enhanced corrosion resistance and a durable, non-reflective finish suitable for industrial environments.
- Hex socket drive (5/64") allows for high-torque installation with standard tools, enabling secure fastening in confined spaces.
- Coarse UNC threads facilitate quicker assembly and disassembly, improving efficiency in maintenance and production workflows.
- Full threading along the 1-1/8" length ensures consistent grip and adjustability across the entire fastener, accommodating various material thicknesses.
- Rockwell C37 hardness provides excellent wear resistance, extending the screw's service life in repetitive or abrasive conditions.
Professional Applications & Engineering Value
These 2-56 UNC Socket Head Cap Screws are engineered to address common industrial challenges such as vibration-induced loosening and corrosion in machinery and equipment. The black-oxide alloy steel construction, combined with a Class 3A thread fit, ensures tight, reliable fastening in high-vibration environments like automotive assemblies, aerospace components, and precision manufacturing tools. The coarse thread design allows for rapid installation, reducing assembly time while maintaining high tensile strength to withstand dynamic loads. Ideal for applications requiring compact, high-strength fasteners with hex drive compatibility, these screws deliver consistent performance in OEM and MRO settings, enhancing operational reliability and reducing maintenance costs.
Specification Summary & Compliance
This product adheres to inch system measurements with a Class 3A thread fit per UNC standards, ensuring precise dimensional accuracy. It meets ASTM A574 specifications for alloy steel socket head cap screws and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming environmental safety and material integrity for global industrial use.
