S-97768A395 5/16"-18 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and black oxide finish, ideal for harsh industrial environments.
• Exceptional load-bearing capacity offering 70,000 psi tensile strength and 35,000 psi shear strength for reliable performance under stress.
• Precise alignment and smooth rotation enabled by the 3 3/4" shoulder with tight diameter tolerance, reducing wear in moving assemblies.
• Secure fastening with minimal play due to Class 3A thread fit and coarse UNC threads, ensuring vibration resistance and easy installation.
• Enhanced grip and tool engagement from the knurled socket head and hex drive, preventing slippage during torque application.
• Long-term durability supported by Rockwell B55 hardness, maintaining integrity through repeated use.
• Broad regulatory compliance meeting ASME B18.3, RoHS 3, and REACH standards for safe, global industrial use.

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical alignment and durability challenges in precision machinery. The 18-8 stainless steel material, combined with a black oxide finish, provides excellent resistance to corrosion and oxidation, making it suitable for applications in automotive, aerospace, and manufacturing equipment where exposure to moisture or chemicals is common. The 3 3/4" shoulder length and precise diameter tolerances allow for accurate positioning of components like gears, pulleys, and bearings, minimizing friction and extending service life. With a coarse UNC thread and Class 3A fit, it ensures quick assembly and reliable retention in high-vibration environments, reducing maintenance downtime. The socket head with knurling enhances tool grip, facilitating efficient installation in confined spaces. Ideal for use in industrial shoulder bolt applications, this screw delivers consistent performance where precision and strength are paramount.

Specification Summary & Compliance

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