S-94361A381 1/2"-20 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capability: With a tensile strength of 140,000 psi, this shoulder screw reliably handles high-stress applications without failure, ensuring long-term operational safety.
• Precision Positioning & Alignment: The 2" shoulder length with tight diameter tolerance (-0.004" to -0.002") guarantees exact component alignment, reducing assembly errors and improving machine performance.
• Superior Corrosion & Wear Resistance: The black oxide finish provides a durable protective layer, extending service life in demanding industrial environments.
• High Thread Reliability: Class 3A UNF fine threads offer superior fit and vibration resistance compared to coarse threads, minimizing loosening in dynamic applications.
• Enhanced Grip & Easy Installation: The knurled head and 5/16" hex drive allow for secure handling and efficient torque application, speeding up assembly processes.
• Consistent Material Performance: Alloy steel with Rockwell C32 hardness ensures uniform strength and durability, supporting repetitive use in automated systems.
• Broad Regulatory Compliance: Meets RoHS 3 and REACH standards, making it suitable for global supply chains and environmentally conscious industries.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical alignment and load distribution challenges in precision machinery. The 2" shoulder length with controlled tolerances acts as a precise pivot or spacer, eliminating misalignment in assemblies like rotating shafts, conveyor systems, and robotic arms. The Class 3A UNF fine thread ensures a tight, secure fit in high-vibration environments, preventing thread stripping and maintaining clamp load. Combined with the black oxide finish, it resists rust and wear in humid or abrasive conditions, reducing maintenance frequency. Ideal for CNC equipment, automotive jigs, and packaging machinery, this screw delivers reliable precision positioning and enhances overall equipment longevity.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit for superior engagement and meets UNF fine thread standards (1/2"-20). Shoulder diameter tolerance is maintained at -0.004" to -0.002", with shoulder length tolerance of -0.005" to 0.005" for consistent precision. Manufactured from alloy steel with Rockwell C32 hardness and 140,000 psi tensile strength, it complies with RoHS 3 (2015/863/EU) under exemption 6(a) and REACH (EC 1907/2006) regulations, ensuring suitability for industrial and export applications.