S-91327A197 3/8"-16 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with permanent nylon patch that maintains secure fastening from -50° to 250°F, preventing loosening in dynamic applications
• Exceptional corrosion resistance through 18-8 stainless steel construction with passivated finish, ensuring longevity in harsh industrial environments
• Precision alignment capability with 2" shoulder length and tight diameter tolerances (-0.004" to -0.002") for accurate component positioning
• High-strength performance delivering 70,000 psi tensile strength and Rockwell B55 hardness for demanding mechanical applications
• Superior thread quality with Class 3A fit and UNC coarse threading providing reliable engagement and installation consistency
• Easy installation and removal through knurled hex socket head design that prevents tool slippage during torque application
• Regulatory compliance assurance meeting ASME B18.3 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

This 3/8"-16 UNC shoulder screw delivers critical engineering solutions for precision machinery and industrial equipment where vibration resistance and alignment accuracy are paramount. The permanent nylon patch thread locker effectively prevents spontaneous loosening in high-vibration environments such as motors, conveyors, and automated systems, while the 18-8 stainless steel construction with passivated finish ensures corrosion resistance in demanding conditions. The precisely machined 2" shoulder length with tight tolerances provides exact component spacing and rotational alignment in assemblies, reducing wear and maintaining operational precision. These shoulder screws are engineered to withstand heavy loads with their 70,000 psi tensile strength, making them ideal for pivots, axles, and mounting applications across manufacturing, automation, and transportation industries.

Specification Summary & Compliance

This shoulder screw features precision Class 3A thread fit with UNC coarse threading (3/8"-16) and maintains dimensional compliance with ASME B18.3 specifications. The shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005" ensure consistent manufacturing quality. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial applications while meeting stringent material restrictions.