S-91259A864 5/8"-11 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 140,000 psi tensile strength and 84,000 psi shear strength for reliable performance in high-stress applications.
• Superior corrosion resistance thanks to the black oxide finish, extending service life in demanding industrial environments.
• Precise alignment and smooth rotation ensured by the 6 1/2" shoulder with tight diameter tolerance for reduced wear on mating components.
• Secure, high-torque installation enabled by the 3/8" hex socket drive and knurled head, preventing slippage during assembly.
• Consistent, reliable thread engagement with Class 3A thread fit and coarse UNC threads for quick assembly and vibration resistance.
• Enhanced durability and wear resistance from Rockwell C32 hardness, maintaining dimensional stability under repeated use.
• Global regulatory compliance meeting ASME B18.3, ASTM A574, RoHS 3, and REACH standards for safe, quality-assured integration.

Professional Applications & Engineering Value

This 5/8"-11 UNC shoulder screw is engineered to address critical alignment and load distribution challenges in industrial machinery, automation systems, and precision equipment. The alloy steel construction, combined with black oxide finish, provides excellent resistance to corrosion and wear, making it ideal for harsh environments. The 6 1/2" shoulder length acts as a precise axle or pivot, reducing friction and preventing misalignment in rotating assemblies like conveyor rollers, gear mechanisms, and robotic arms. With a Class 3A thread fit and coarse UNC threads, it ensures fast, secure fastening even in high-vibration settings, while the socket head design allows for compact installation in confined spaces. This screw delivers reliable performance in applications requiring high strength and dimensional accuracy, minimizing downtime and maintenance costs.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit and UNC thread standards for precise dimensional control. Shoulder diameter tolerance is -0.004" to -0.002", and shoulder length tolerance is -0.005" to 0.005", ensuring consistent performance. Manufactured in compliance with ASME B18.3 and ASTM A574 specifications, it also meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, guaranteeing safety and sustainability in industrial use.