S-90117A537 1/4"-20 x 1/2" ASME B18.3 Alloy Steel Wire-Lockable Socket Head Screws

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 on alloy steel, extending service life in harsh industrial environments without compromising structural integrity.
• Precise Class 3A thread fit guarantees tight, secure connections with minimal backlash, ideal for applications requiring vibration resistance and repeatable assembly.
• Hex socket drive design allows for high-torque installation with standard tools, enabling efficient assembly and maintenance in confined spaces.
• Full threading along the 1/2" length provides uniform load distribution and versatile positioning, accommodating various material thicknesses without sacrificing grip.
• Coarse UNC thread profile facilitates quick installation and reduces cross-threading risks, speeding up production cycles in high-volume settings.
• Compliance with ASME B18.3 and environmental regulations ensures interoperability with standardized components and adherence to global safety and sustainability mandates.

Professional Applications & Engineering Value

Engineered for industrial machinery, automotive assemblies, and precision equipment, this socket head cap screw addresses critical challenges like vibration-induced loosening and environmental degradation. The black-oxide alloy steel construction combats rust and wear, while the Class 3A thread fit maintains alignment in dynamic loads. Its 1/4"-20 UNC coarse thread and hex drive enable rapid, secure fastening in tight spaces, reducing downtime. By integrating high tensile strength with standardized dimensions, it supports reliable fastening solutions in sectors demanding durability and regulatory compliance, from manufacturing to aerospace.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit tolerances per UNC standards, ensuring precise engagement. Manufactured under ASME B18.3 specifications, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance for environmental safety. Dimensions include a 1/2" length with fully threaded coarse spacing, backed by Rockwell C37 hardness for consistent performance.