S-97768A381 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and black oxide finish, ensuring longevity in harsh industrial environments.
• High load-bearing capacity offering 70,000 psi tensile strength and 35,000 psi shear strength for reliable performance in demanding applications.
• Precise alignment and spacing due to the 2" shoulder with tight tolerances, reducing assembly errors and improving mechanical stability.
• Easy installation and removal with a hex socket drive and knurled head, providing secure grip and reducing tool slippage.
• Consistent thread engagement from Class 3A fit and 1/4-20 UNC coarse thread, ensuring secure fastening and vibration resistance.
• Enhanced durability with Rockwell B55 hardness, maintaining structural integrity under repeated stress and wear.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, guaranteeing safety and regulatory adherence for global use.

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical alignment and durability challenges in industrial fastening applications. The 18-8 stainless steel material combined with a black oxide finish provides excellent corrosion resistance, making it ideal for machinery, automotive, and electronics assemblies exposed to moisture or chemicals. The 2" shoulder length with precise tolerances ensures accurate component spacing, reducing misalignment and wear in rotating parts like bearings and pulleys. With a hex drive and knurled head, it allows for quick, secure installation, minimizing downtime. The 1/4-20 UNC coarse thread and Class 3A fit deliver reliable clamping force, preventing loosening in high-vibration environments, thereby enhancing overall assembly reliability and lifespan.

Specification Summary & Compliance

This shoulder screw features a 1/4-20 UNC thread with Class 3A fit for high precision, and a shoulder diameter of 3/8" with tight tolerances (-0.004" to -0.002") to ensure consistent performance. It meets ASME B18.3 specifications for dimensional accuracy and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for various industrial sectors.