S-8077A498 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh environments and extended service life.
• Exceptional mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for reliable performance in demanding applications.
• Precise and secure fit ensured by the Class 3A thread tolerance, minimizing the risk of loosening under vibration.
• Enhanced durability and wear resistance from the black oxide finish, which also provides a sleek, non-reflective appearance.
• Easy and secure installation with a standard socket (hex) head and 5/64" drive, complemented by a knurled texture for improved grip.
• Robust shoulder design with a 15/16" length and tight tolerances for accurate component alignment and spacing.
• Compliance with major environmental regulations including RoHS 3 and REACH, ensuring safety and suitability for global markets.

Professional Applications & Engineering Value

This 4-40 UNC shoulder screw is engineered to solve critical challenges in precision assembly and industrial machinery. The 316 stainless steel material provides outstanding resistance to corrosion and chemicals, making it perfect for marine, chemical processing, and food-grade equipment where moisture and aggressive agents are present. The black oxide finish not only enhances corrosion protection but also reduces galling during installation. With its Class 3A thread fit and robust 70,000 psi tensile strength, it ensures a secure, vibration-resistant connection in applications like pivots, rotating shafts, and spacers. The knurled head and socket drive allow for easy torque application in confined spaces, improving assembly efficiency and reliability in automated systems and high-precision instruments.

Specification Summary & Compliance

This shoulder screw adheres to UNC coarse thread standards with a Class 3A thread fit for high precision. Key dimensional tolerances include a shoulder diameter tolerance of -0.004" to -0.002" and a shoulder length tolerance of -0.005" to 0.005". It is manufactured to deliver 70,000 psi tensile strength and 35,000 psi minimum shear strength, with a material hardness of Rockwell B79. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets stringent environmental and safety standards for industrial use.