S-97768A271 8-32 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and black oxide finish, ideal for harsh industrial environments.
• Exceptional mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for heavy-duty, high-stress applications.
• Precise alignment and spacing ensured by the 2" shoulder with controlled tolerances, reducing assembly errors and improving component fit.
• Reliable, vibration-resistant threading with 8-32 UNC coarse threads and Class 3A fit for secure fastening in dynamic conditions.
• Easy installation and removal using the hex socket drive and knurled head, providing superior grip and torque application.
• Compliance with major industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety and regulatory acceptance.
• Durable performance backed by Rockwell B55 hardness, maintaining integrity under repeated use and load.

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical alignment and load-bearing challenges in precision machinery, automation systems, and assembly jigs. The 18-8 stainless steel material combined with a black oxide finish provides excellent resistance to rust and wear, extending service life in moist or chemically exposed settings. The 2" shoulder length and precise diameter tolerances allow for accurate positioning of moving parts like gears, pulleys, and linkages, minimizing backlash and misalignment. With UNC coarse threads and a Class 3A thread fit, it ensures tight, reliable connections that resist loosening under vibration, making it ideal for industrial equipment, robotics, and automotive applications where durability and precision are paramount.

Specification Summary & Compliance

The screw features an 8-32 UNC thread with Class 3A fit for high precision, a shoulder diameter of 1/4" with tight tolerances (-0.004" to -0.002"), and a shoulder length of 2" (±0.005"). It is manufactured in compliance with ASME B18.3 standards and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring it is free of hazardous substances and suitable for global industrial use.