S-94383A390 5/16"-18 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional strength and durability with alloy steel construction and 140,000 psi tensile strength, ensuring reliable performance in high-stress applications.
• Superior corrosion resistance thanks to the black oxide finish, extending service life in harsh industrial environments.
• Precise alignment and reduced wear with a 2" shoulder length and tight ±0.005" tolerance, providing stable bearing surfaces for moving parts.
• High thread reliability with Class 3A fit and UNC coarse thread, offering excellent vibration resistance and easier assembly.
• Secure and easy installation featuring a knurled socket head with hex drive, preventing slippage and enabling efficient torque application.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety, quality, and environmental responsibility.
• Optimal hardness and shear strength with Rockwell C32 hardness and 84,000 psi minimum shear strength, resisting deformation under heavy loads.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical challenges in precision machinery and industrial assemblies. The 2" shoulder length with minimal tolerance provides a stable pivot or axle, reducing misalignment and wear in rotating components like gears, pulleys, and linkages. The black oxide finish enhances corrosion resistance, making it ideal for environments exposed to moisture or chemicals. With a Class 3A thread fit and UNC coarse thread, it ensures secure fastening in high-vibration settings, such as automotive or manufacturing equipment. The knurled socket head allows for quick, tool-friendly installation, minimizing downtime. By meeting ASME B18.3 specifications, it delivers consistent performance for demanding applications like robotics, conveyor systems, and precision instruments, where reliability and durability are paramount.

Specification Summary & Compliance

This shoulder screw adheres to precise dimensional standards, including a Class 3A thread fit for tight tolerances and a shoulder length tolerance of ±0.005". It conforms to ASME B18.3 manufacturing specifications and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for global industrial use.