S-8077A572 5/16"-18 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel and Black Oxide finish, ideal for harsh environments and extended service life.
• High mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for reliable performance under heavy loads.
• Precise Class 3A thread fit ensures tight, secure fastening with minimal backlash in critical assemblies.
• Convenient installation and removal via a socket head with a 3/16" hex drive and knurled head for enhanced grip.
• Accurate alignment and spacing with a 4" shoulder length and controlled tolerances for consistent component positioning.
• Broad industry compliance meeting ASME B18.3 standards, RoHS 3, and REACH for safe, regulated use.
• Durable coarse UNC threading provides robust engagement and resistance to vibration loosening in dynamic applications.

Professional Applications & Engineering Value

This 316 Stainless Steel shoulder screw is engineered to address common industrial challenges such as misalignment, corrosion, and mechanical failure. The Black Oxide finish enhances surface durability and provides an additional layer of protection against oxidation and wear, making it suitable for applications in marine, chemical processing, and outdoor equipment. The 4" shoulder length and precise diameter tolerances ensure accurate pivot points and bearing surfaces in machinery, reducing wear on moving parts. With a Class 3A thread fit and coarse UNC threading, it offers quick assembly and high resistance to vibration, ideal for use in industrial fasteners for conveyors, robotic arms, and precision instruments. The combination of high tensile and shear strength supports heavy-duty operations, while the socket head design allows for easy access in confined spaces, streamlining maintenance and reducing downtime.

Specification Summary & Compliance

This shoulder screw features a 5/16"-18 UNC thread with Class 3A fit for high precision, a shoulder diameter of 3/8" with tight tolerances (-0.004" to -0.002"), and a shoulder length of 4" (±0.005"). It complies with ASME B18.3 specifications for dimensional accuracy and is RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, ensuring environmental safety and regulatory adherence in industrial applications.