S-90311A111 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel construction, ideal for harsh industrial environments and extending service life.
• Secure, vibration-resistant fastening thanks to the integrated Nylon Patch thread locker, preventing loosening under dynamic loads.
• High-strength performance delivering 70,000 psi tensile and 35,000 psi shear strength for reliable use in demanding applications.
• Precise and reliable fit ensured by the Class 3A thread fit, providing consistent clamping force and assembly accuracy.
• Wide operational temperature range from -50° to 250° F, maintaining locking integrity in varied thermal conditions.
• Easy installation and removal with a standard hex socket (5/64" drive) and knurled head for improved grip and torque application.
• 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 thread shoulder screw is engineered to address critical challenges in precision assemblies where alignment and vibration resistance are paramount. The 316 Stainless Steel material offers excellent resistance to corrosion from chemicals and moisture, making it ideal for industrial applications in marine, chemical processing, and food equipment. The coarse UNC thread and Class 3A fit ensure quick assembly with high accuracy, while the Nylon Patch thread locker provides a dependable locking mechanism that eliminates the need for additional adhesives, reducing assembly time and cost. The robust socket head with hex drive allows for high-torque installation in confined spaces, enhancing efficiency in automated production lines and machinery maintenance.

Specification Summary & Compliance

This shoulder screw features a 4-40 UNC coarse thread with a Class 3A thread fit for precise dimensional accuracy. Key specifications include a shoulder diameter of 1/8" with a tolerance of -0.004" to -0.002", and a shoulder length of 1/8" with a tolerance of -0.005" to 0.005". It is manufactured to high standards with a hardness of Rockwell B79 and complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability for industrial and engineering use.