S-91264A716 1/2"-13 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capability: With a tensile strength of 140,000 psi and shear strength of 84,000 psi, this screw ensures reliable performance in high-stress industrial environments.
• Secure Vibration-Resistant Locking: Integrated nylon pellet thread locker maintains fastener integrity across a wide temperature range from -50° to 250°F, preventing loosening under dynamic loads.
• Precision Thread Fit for Accurate Assembly: Class 3A thread fit provides tight tolerances, reducing the risk of cross-threading and ensuring consistent, repeatable installations.
• Corrosion-Resistant Surface Protection: Black oxide finish enhances durability by resisting rust and wear, extending service life in harsh operating conditions.
• Optimized Shoulder Design for Component Alignment: The 1 1/2" shoulder with controlled diameter tolerance facilitates precise positioning of moving parts, minimizing misalignment and wear.
• Easy Installation with Standard Drive System: 5/16" hex socket drive allows for efficient torque application using common tools, speeding up assembly and maintenance processes.
• Compliance with Industry Standards: Meets ASME B18.3 and ASTM A574 specifications, ensuring interoperability and reliability in regulated applications.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical challenges in machinery assembly, where vibration resistance and component alignment are paramount. The 1/2"-13 UNC coarse thread with Class 3A fit ensures rapid, secure fastening in heavy-duty equipment, while the nylon pellet locking mechanism eliminates the need for additional adhesives, simplifying maintenance in industrial automation and precision manufacturing systems. The black oxide finish provides a protective layer against corrosion, making it suitable for environments exposed to moisture or chemicals. By integrating a knurled socket head and standardized hex drive, it reduces installation time and tool wear, delivering consistent performance in conveyor systems, robotic arms, and fixturing applications.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit per UNC standards, with a shoulder diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005" for precise dimensional control. It conforms to ASME B18.3 and ASTM A574 manufacturing specifications, ensuring material consistency and mechanical properties. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, supporting environmentally responsible sourcing and usage in global markets.