S-8077A795 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh industrial environments and prolonged service life.
• Exceptional mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for reliable performance under high-stress conditions.
• Precise alignment and smooth rotation enabled by the 5" shoulder length with tight tolerances, reducing wear on mating components.
• High-accuracy Class 3A thread fit ensures secure, vibration-resistant fastening with the 1/4"-20 UNC coarse thread for quick assembly.
• Enhanced durability and minimal maintenance from the black oxide finish, which provides added corrosion protection and a sleek appearance.
• Secure, non-slip installation with the knurled socket head and hex drive, allowing for high-torque application without stripping.
• Compliance with industry standards including ASME B18.3, ensuring consistent quality and interchangeability in professional applications.

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to address critical challenges in industrial fastening, such as misalignment and component wear. The 5" shoulder length provides a precise pivot or bearing surface, commonly used in machinery, automation systems, and assembly jigs where smooth rotational movement is essential. The black oxide finish enhances corrosion resistance, making it suitable for moist or chemically aggressive environments, while the Class 3A thread fit and UNC coarse thread ensure quick, reliable assembly with high resistance to loosening under vibration. With a Rockwell B79 hardness and robust tensile strength, it delivers long-term reliability in heavy-duty applications, reducing downtime and maintenance costs.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 specifications, with precise dimensions including a 1/4"-20 UNC thread and Class 3A thread fit for high accuracy. The shoulder diameter tolerance is -0.004" to -0.002", and shoulder length tolerance is -0.005" to 0.005", ensuring consistent performance. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmentally responsible and safe use in various industrial sectors.