S-91264A626 3/8"-16 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity – With 140,000 psi tensile strength and 84,000 psi shear strength, this shoulder screw reliably handles high-stress applications without failure.
• Secure Vibration-Resistant Locking – Integrated nylon pellet thread locker maintains fastener integrity in temperatures from -50° to 250°F, preventing loosening in dynamic environments.
• Precision Shoulder Alignment – Tight shoulder diameter tolerance (-0.004" to -0.002") ensures accurate component positioning and smooth rotational movement.
• Durable Corrosion-Resistant Finish – Black oxide coating on alloy steel enhances wear resistance and provides moderate protection against rust in industrial settings.
• High-Strength Material Construction – Alloy steel with Rockwell C32 hardness offers superior durability and fatigue resistance for long service life.
• Industry-Standard Compliance – Manufactured to ASME B18.3 and ASTM A574 specifications, guaranteeing consistent quality and dimensional accuracy.
• Easy Installation with Hex Drive – 1/4" hex socket drive allows for efficient tightening in confined spaces using standard tools.

Professional Applications & Engineering Value

This 3/8"-16 UNC shoulder screw is engineered to solve critical alignment and vibration challenges in precision assemblies. The alloy steel construction with black oxide finish provides the necessary strength and moderate corrosion resistance for demanding environments like machinery, automotive fixtures, and rotating equipment. The 1 1/4" shoulder length acts as a precise axle or pivot point, maintaining component spacing while reducing wear on moving parts. Combined with the Class 3A thread fit and nylon pellet thread locker, it effectively prevents backlash and self-loosening under continuous vibration, ensuring reliable performance in industrial shoulder bolt applications where operational stability is paramount.

Specification Summary & Compliance

This shoulder screw features 3/8"-16 UNC coarse threads with Class 3A thread fit for precise engagement, and shoulder dimensions maintained within tight tolerances (diameter: -0.004" to -0.002"; length: -0.005" to 0.005"). It is manufactured in compliance with ASME B18.3 and ASTM A574 standards, and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations.