S-91259A705 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, these screws reliably handle high-stress applications without failure.
• Superior Corrosion & Wear Resistance: The black oxide finish on alloy steel provides enhanced durability in harsh industrial environments.
• Precision Alignment & Stability: The 1/2" shoulder diameter with tight tolerances ensures accurate component positioning and reduces wear on mating parts.
• High Thread Reliability: Class 3A thread fit with UNC coarse threads offers secure fastening and vibration resistance in dynamic assemblies.
• Easy Installation & High Torque Transfer: The 1/4" hex socket drive and knurled head allow for efficient tightening with standard tools, minimizing installation time.
• Consistent Performance & Compliance: Manufactured to ASME B18.3 standards with Rockwell C32 hardness, ensuring uniform quality and mechanical properties.
• Environmentally Safe for Global Use: Compliant with RoHS 3 and REACH regulations, making them suitable for international supply chains and sensitive applications.

Professional Applications & Engineering Value

This 3/8"-16 UNC shoulder screw is engineered to address critical challenges in precision machinery and heavy-duty equipment. The alloy steel construction, combined with a black oxide finish, provides excellent resistance to corrosion and abrasion, extending service life in demanding environments like automotive assemblies, industrial robots, and conveyor systems. The socket head with hex drive design allows for compact installation in confined spaces, while the shoulder diameter acts as a precise pivot or bearing surface, reducing alignment issues and component wear. By integrating Class 3A thread fit and high tensile strength, these screws ensure reliable performance under dynamic loads, minimizing maintenance downtime and enhancing operational safety in industrial applications.

Specification Summary & Compliance

This shoulder screw features a 3/8"-16 UNC thread with Class 3A fit for precise engagement, and a shoulder diameter of 1/2" with tolerances from -0.004" to -0.002". It meets ASME B18.3 specifications and is manufactured from alloy steel hardened to Rockwell C32. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) standards, ensuring adherence to environmental and safety regulations for global industrial use.