S-94383A350 5/16"-18 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Tensile and Shear Strength: Withstands up to 140,000 psi tensile and 84,000 psi shear forces, ensuring reliable performance in high-stress industrial applications.
• Superior Corrosion Resistance: Black oxide finish provides enhanced protection against rust and wear, extending service life in harsh environments.
• Precision Thread Fit: Class 3A UNC coarse threads offer tighter tolerances for secure, vibration-resistant fastening and reduced risk of loosening.
• Durable Alloy Steel Construction: Made from high-grade alloy steel with Rockwell C32 hardness for excellent wear resistance and long-term durability.
• Easy Installation and Removal: Hex socket drive (3/16") and knurled head allow for quick, slip-resistant tool engagement, speeding up assembly and maintenance.
• Accurate Shoulder Dimensions: Tight shoulder diameter and length tolerances ensure precise alignment and smooth rotation in machinery and pivoting applications.
• Compliance with Industry Standards: Meets ASME B18.3, RoHS 3, and REACH regulations, guaranteeing safety and environmental responsibility for global supply chains.

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical challenges in precision machinery, automation, and assembly systems. The alloy steel core, combined with a black oxide finish, resists corrosion and abrasion, making it ideal for environments exposed to moisture, chemicals, or frequent movement. The 5/16"-18 UNC coarse thread and Class 3A fit ensure secure fastening with minimal backlash, crucial for applications like rotating shafts, linkages, and bearing mounts where alignment and stability are paramount. The knurled head and hex drive facilitate easy installation even in confined spaces, reducing assembly time and improving maintenance efficiency. By providing consistent performance in high-load scenarios, this screw minimizes downtime and enhances the reliability of industrial equipment.

Specification Summary & Compliance

The screw features precise dimensions, including a shoulder diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005", ensuring accurate fits for standard shoulder applications. Threads adhere to UNC coarse standards with a Class 3A fit for superior engagement. Manufacturing complies with ASME B18.3 specifications under ASTM A574, and it is fully RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, meeting environmental and safety requirements for industrial use.