S-90311A137 8-32 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh or chemical-exposed industrial environments.
• Vibration-resistant locking provided by the integrated nylon patch, ensuring fastener integrity from -50°F to 250°F without loosening.
• High mechanical strength delivering 70,000 psi tensile and 35,000 psi minimum shear strength for demanding, high-stress applications.
• Precise Class 3A thread fit for tighter tolerances and reliable engagement in UNC coarse threading, reducing assembly play.
• Easy installation and removal with a standard hex socket (3/32" drive) and knurled head for improved grip during tool handling.
• Accurate shoulder dimensions with controlled diameter and length tolerances, providing consistent alignment and spacing in assemblies.
• Compliance with global regulations including RoHS 3 and REACH, ensuring safety and environmental standards for international supply chains.

Professional Applications & Engineering Value

This 8-32 UNC shoulder screw is engineered to address critical challenges in precision machinery, automation systems, and heavy-duty equipment. The 316 stainless steel material offers exceptional resistance to corrosion and oxidation, making it suitable for marine, chemical processing, and outdoor applications. The integrated nylon patch thread locker secures the fastener against vibrations and thermal cycling, eliminating the need for separate locking washers or adhesives. With a Class 3A thread fit and a robust shoulder diameter of 3/16", it provides exact positioning and load distribution in pivots, linkages, and rotating assemblies. The coarse UNC threads ensure quick assembly and high fatigue resistance, while the socket head with hex drive allows for compact installation in confined spaces. Ideal for OEMs and MRO professionals, this screw enhances assembly reliability, reduces maintenance cycles, and supports long-term operational efficiency.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 3A thread fit for precision engagement. Key dimensional tolerances include a shoulder diameter of 3/16" (tolerance: -0.004" to -0.002") and shoulder length of 5/8" (tolerance: -0.005" to 0.005"). The fastener is manufactured to meet RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, ensuring it is free of hazardous substances and suitable for regulated industrial markets. Mechanical properties include a hardness of Rockwell B79, tensile strength of 70,000 psi, and minimum shear strength of 35,000 psi, validating its use in high-performance applications.