S-94383A380 5/16"-18 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Superior load-bearing capacity with 140,000 psi tensile strength and 84,000 psi shear strength for reliable performance in high-stress applications.
• Precision alignment and smooth rotation ensured by the 1-1/2" shoulder with tight diameter tolerance for consistent part positioning.
• Enhanced corrosion resistance from the black oxide finish, extending service life in demanding industrial environments.
• Secure, non-slip installation with a knurled socket head and hex drive for improved grip and torque application.
• High thread reliability due to Class 3A fit and coarse UNC thread, reducing cross-threading risks and ensuring stable connections.
• Exceptional durability from Rockwell C32 hardened alloy steel, resisting wear and deformation under repeated use.
• Broad compliance with ASME B18.3, RoHS 3, and REACH standards, ensuring safety and environmental responsibility.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical challenges in precision machinery and assembly systems. The 1-1/2" shoulder length provides a stable bearing surface for rotating components like gears and pulleys, minimizing misalignment and reducing wear on mating parts. Its black oxide finish offers reliable corrosion protection in humid or abrasive conditions, while the Class 3A thread fit and coarse UNC thread ensure quick, secure fastening without sacrificing strength. Ideal for industrial automation, automotive fixtures, and conveyor systems, this screw delivers consistent performance where exact tolerances and high shear strength are paramount. The knurled socket head enhances handling during installation, speeding up maintenance and reducing downtime in production environments.

Specification Summary & Compliance

This shoulder screw maintains precise dimensional accuracy with a shoulder diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005". It features 5/16"-18 UNC coarse threads with a Class 3A fit for superior engagement, manufactured in accordance with ASME B18.3 specifications using ASTM A574 alloy steel. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets stringent environmental and safety standards for global industrial use.