S-91251A035 1 1/2"-12 x 3 1/2" 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.
• Black-oxide coating on alloy steel provides enhanced corrosion resistance and a durable finish for extended service life in harsh environments.
• Fine UNRF Class 2A threads offer superior vibration resistance and precise fit, minimizing loosening in dynamic assemblies.
• Fully threaded design allows for consistent clamping force along the entire length, improving joint integrity in heavy-duty setups.
• 1" hex drive socket head enables easy installation with standard tools, reducing assembly time and enhancing workplace efficiency.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety, meeting global industry standards.
• Rockwell C37 hardness ensures high wear resistance, maintaining thread integrity and durability under repetitive loads.

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-induced loosening and corrosion in machinery. The fine UNRF Class 2A threads provide a tight, secure fit that resists back-off in high-vibration environments like automotive or aerospace assemblies. With a 170,000 psi tensile strength and Rockwell C37 hardness, it withstands extreme mechanical stresses without deformation, making it ideal for heavy-duty applications in construction equipment or manufacturing systems. The fully threaded design ensures uniform load distribution, while the 1" hex drive simplifies maintenance in confined spaces. By combining durability with precision, these screws enhance assembly reliability and reduce downtime in demanding operations.

Specification Summary & Compliance

This socket head cap screw features precise Class 2A thread fit with UNRF fine threads and a 1 1/2"-12 thread size, ensuring accurate engagement in inch-system applications. It complies with ASTM A574 specifications for high-strength alloy steel fasteners, along with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial use without hazardous substances.