S-91259A116 3/8"-16 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Superior load-bearing capability with 140,000 psi tensile strength and 84,000 psi minimum shear strength for demanding industrial applications
• Precise component alignment through Class 3A thread fit and controlled shoulder diameter tolerances (-0.004" to -0.002")
• Enhanced corrosion resistance with black oxide finish protecting against environmental degradation in harsh operating conditions
• Optimized torque transmission via 1/4" hex drive socket head with knurled texture for secure tool engagement
• Reliable mechanical performance ensured by Rockwell C32 hardness and alloy steel construction
• Simplified assembly processes with UNC coarse threads and 5 1/2" shoulder length providing stable rotational support
• Regulatory compliance assurance meeting ASME B18.3 specifications and RoHS/REACH environmental standards

Professional Applications & Engineering Value

This alloy steel shoulder screw delivers exceptional engineering value in precision mechanical assemblies where exact component positioning is critical. The 3/8"-16 UNC coarse threads with Class 3A fit provide secure fastening while the precisely machined 1/2" shoulder diameter acts as a reliable locating surface for bearings, gears, and rotating components. The black oxide finish offers substantial corrosion protection in industrial environments, extending service life without compromising dimensional accuracy. With its 5 1/2" shoulder length maintaining tight tolerances, this socket head shoulder screw solves alignment challenges in machinery, automation systems, and precision equipment where vibration resistance and positional stability are paramount. The combination of high-strength alloy steel and controlled manufacturing tolerances makes it ideal for applications requiring repeated disassembly and reassembly without performance degradation.

Specification Summary & Compliance

This shoulder screw maintains Class 3A thread fit per UNC standards with precise dimensional control including shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005". Manufactured to ASME B18.3 specifications with material compliance to ASTM A574, ensuring consistent performance across industrial applications. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for industrial components.