S-91264A170 3/8"-16 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capability – With 140,000 psi tensile and 84,000 psi shear strength, this shoulder screw reliably handles high-stress applications without failure.
• Secure Vibration-Resistant Locking – Integrated nylon pellet thread locker maintains fastener integrity in dynamic environments from -50° to 250°F.
• Precision Alignment & Reduced Wear – Class 3A UNC thread fit and standard shoulder fit ensure accurate positioning and minimize component abrasion.
• Corrosion Resistance & Durability – Black oxide finish on alloy steel provides enhanced protection against rust in demanding industrial settings.
• Easy Installation & Removal – Hex socket drive with knurled head offers superior grip and torque application for efficient maintenance.
• Rigorous Quality Assurance – Manufactured to ASME B18.3 standards, guaranteeing consistent performance and interchangeability.
• Broad Operational Compatibility – RoHS 3 and REACH compliance ensures safe use across various industries without regulatory concerns.

Professional Applications & Engineering Value

This 3/8"-16 UNC shoulder screw is engineered to address critical challenges in precision machinery, automated assembly systems, and rotating equipment. The alloy steel construction, hardened to Rockwell C32, resists deformation under continuous load, while the black oxide finish adds a layer of corrosion resistance essential in humid or chemically exposed environments. The 1/2" shoulder diameter and 4" shoulder length provide a stable pivot or spacer, reducing misalignment and wear on adjacent parts. Integrated nylon pellet thread locker secures the fastener against loosening from vibrations, common in motors and conveyors, ensuring long-term reliability without the need for additional adhesives. By combining high tensile strength with precise Class 3A thread fit, this screw minimizes downtime and maintenance costs in industrial applications requiring repeatable accuracy.

Specification Summary & Compliance

This shoulder screw features Class 3A thread fit with UNC coarse threading for secure engagement, and shoulder diameter tolerance of -0.004" to -0.002" for precise assembly. It conforms to ASME B18.3 specifications and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability.