S-91670A313 10-32 x 3/4" ASTM A574 Left-Hand Threaded Alloy Steel 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 critical assemblies.
• Corrosion-resistant black-oxide coating on alloy steel enhances durability and extends service life in harsh industrial environments.
• Precision Class 3A thread fit provides superior engagement and vibration resistance, ideal for applications requiring tight tolerances.
• Left-hand UNF fine threading offers secure fastening in reverse-thread applications, preventing loosening from counter-clockwise motion.
• Standard hex socket drive allows for easy installation with common tools, improving assembly efficiency and reducing downtime.
• Full threading along the 3/4" length ensures consistent grip and adjustability across the entire fastener for versatile mounting solutions.
• Compliance with ASTM A574, RoHS 3, and REACH guarantees material quality and environmental safety, meeting global regulatory standards.

Professional Applications & Engineering Value

Engineered for demanding industrial settings, these black-oxide alloy steel socket head cap screws address common challenges like vibration-induced loosening and corrosion. The left-hand thread design is crucial in machinery where reverse rotation occurs, maintaining secure fastening without additional locking mechanisms. With a Rockwell C37 hardness and 170,000 psi tensile strength, they withstand extreme loads in automotive, aerospace, and heavy equipment assemblies. The 10-32 UNF fine thread and Class 3A fit ensure precise alignment and reduced wear, while the black-oxide surface treatment resists rust, making them suitable for humid or abrasive environments. This combination delivers long-term reliability, minimizing maintenance needs and downtime in high-performance fastener applications.

Specification Summary & Compliance

This socket head cap screw adheres to inch system measurements with a length of 3/4", head diameter of 5/16", and 5/32" hex drive. Thread specifications include 10-32 UNF left-hand fine threads with a Class 3A fit for high precision. Manufacturing follows ASTM A574 standards, ensuring consistent quality and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and safe for industrial use.