S-8077A632 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from 316 stainless steel construction, ideal for harsh industrial environments and outdoor applications.
• Exceptional mechanical strength with a tensile strength of 70,000 psi and shear strength of 35,000 psi for reliable performance under high stress.
• Precise alignment and reduced wear with a Class 3A thread fit and standard shoulder fit, ensuring accurate component positioning and longevity.
• Enhanced durability and wear resistance provided by the black oxide finish, which also offers a sleek, non-reflective appearance.
• Secure and easy installation with a knurled socket head and 3/16" hex drive, allowing for high-torque application without slippage.
• Broad compatibility with 1/4"-20 UNC coarse threads, making it suitable for a wide range of machinery and assembly applications.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring product safety and environmental responsibility.

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to address critical challenges in precision assembly and motion control systems. The 3" shoulder length acts as a precise pivot, shaft, or spacer, minimizing misalignment and wear in rotating assemblies such as gears, bearings, and linkages. The Class 3A thread fit and coarse UNC threads provide secure fastening with excellent resistance to vibration loosening, which is vital in high-cycle machinery. The black oxide finish not only enhances corrosion resistance but also reduces galling, a common issue in stainless steel fasteners. Combined with a knurled socket head for non-slip torque application, this screw delivers reliable performance in demanding sectors like automation, packaging equipment, and material handling, where precision and durability are non-negotiable.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit for high precision and features a shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005". It conforms to ASME B18.3 specifications and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets strict industry and environmental standards for safe use in global markets.