S-90298A813 1/2"-13 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh environments and reducing replacement frequency
• Enhanced installation security through the knurled hex socket head design, preventing tool slippage and ensuring precise torque application
• High mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness, providing reliable performance under heavy loads
• Precise component alignment enabled by the 4 3/4" shoulder length with tight tolerances, minimizing assembly play and vibration
• Secure thread engagement with Class 3A thread fit and 1/2"-13 UNC coarse threads, offering excellent vibration resistance and faster assembly
• Broad regulatory compliance meeting ASME B18.3, RoHS 3, and REACH standards, ensuring quality and environmental safety for global projects
• Optimized for industrial duty with 35,000 psi minimum shear strength, suitable for high-stress mechanical applications

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical alignment and durability challenges in precision industrial applications. The 18-8 Stainless Steel material provides excellent corrosion resistance, extending service life in moist or chemically aggressive environments. The 4 3/4" shoulder length with controlled tolerances ensures accurate positioning of moving parts like gears, pulleys, and linkages, reducing wear and maintenance downtime. Combined with the Class 3A thread fit and coarse UNC threads, it delivers robust, vibration-resistant fastening for machinery, automotive assemblies, and conveyor systems. The hex socket drive with knurling enhances grip during installation, preventing cam-out and ensuring consistent clamping force in high-torque applications.

Specification Summary & Compliance

This shoulder screw maintains Class 3A thread fit per UNC standards, with shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005" for precise assembly. It is manufactured in compliance with ASME B18.3 specifications and adheres to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring both dimensional accuracy and material safety for industrial use.