S-8077A636 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and black oxide finish, ideal for harsh industrial environments.
• Precise alignment and secure pivoting ensured by the 3/8" shoulder diameter with tight tolerance control.
• High-strength performance with 70,000 psi tensile strength and 35,000 psi shear strength for demanding mechanical applications.
• Reliable, vibration-resistant fastening due to the Class 3A thread fit and coarse UNC thread for quick assembly.
• Easy installation and removal with a hex socket drive and knurled head for improved grip and torque application.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH for quality and environmental safety.
• Durable, long-lasting use supported by Rockwell B79 hardness and robust material properties.

Professional Applications & Engineering Value

This 1/4"-20 UNC shoulder screw is engineered to address critical challenges in precision machinery and assembly. The 316 stainless steel material, combined with a black oxide finish, provides exceptional corrosion resistance, making it suitable for applications exposed to moisture, chemicals, or outdoor conditions. The coarse thread design allows for faster installation and reduces cross-threading risks, while the Class 3A thread fit ensures tight, secure connections that resist loosening under vibration. Commonly used in industrial equipment, such as pivoting joints, gear assemblies, and conveyor systems, the shoulder screw offers a precise shoulder diameter for accurate component alignment and smooth rotational movement. Its hex drive and knurled head enhance usability in tight spaces, improving efficiency in maintenance and production lines.

Specification Summary & Compliance

This shoulder screw adheres to strict dimensional and performance standards, including Class 3A thread fit for precise tolerance and UNC coarse thread specifications. It meets ASME B18.3 manufacturing guidelines, ensuring consistency and reliability. The product is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and safe for various industrial applications. Key specifications include a shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005", providing the accuracy required for high-performance assemblies.