S-8077A499 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 316 Stainless Steel construction, ideal for harsh environments including marine and chemical applications.
• Enhanced durability and wear resistance from the Black Oxide finish, providing a protective layer that reduces galling and extends service life.
• Superior load-bearing capacity with a tensile strength of 70,000 psi and shear strength of 35,000 psi, ensuring reliable performance under high stress.
• Precise and secure fit due to the Class 3A thread fit, minimizing backlash and improving assembly accuracy in precision mechanisms.
• Easy installation and removal with a hex socket drive and knurled head, offering excellent grip and torque transmission without slippage.
• Stable shoulder alignment featuring a consistent shoulder diameter and length, providing reliable pivoting and spacing in assemblies.
• Compliance with environmental standards including RoHS 3 and REACH, ensuring safe use in regulated industries worldwide.

Professional Applications & Engineering Value

This 4-40 UNC shoulder screw is engineered to address critical challenges in precision industrial applications, such as machinery linkages, pivoting assemblies, and electronic enclosures. The 316 Stainless Steel material offers superior resistance to corrosion and high temperatures, making it suitable for demanding environments like marine equipment or chemical processing plants. The Black Oxide finish not only enhances aesthetic appeal but also reduces friction and wear, preventing seizing during repeated adjustments. With a Class 3A thread fit and coarse threading, it ensures quick assembly and reliable holding power, minimizing the risk of loosening under vibration. The knurled head and hex drive design facilitate easy handling with standard tools, streamlining maintenance and reducing downtime in automated systems. Ideal for applications requiring exact shoulder positioning, this screw delivers consistent performance in robotics, aerospace components, and medical devices where precision and durability are paramount.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 3A thread fit for high precision, ensuring tight tolerances and reliable engagement. Key dimensions include a shoulder diameter of 1/8" with a tolerance of -0.004" to -0.002" and a shoulder length of 15/32" with a tolerance of -0.005" to 0.005", providing consistent alignment. Manufactured from 316 Stainless Steel with a Black Oxide finish, it meets industry standards for mechanical properties, including a hardness of Rockwell B79. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for global markets.