S-91259A744 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.
• Precision Thread Fit for Secure Assembly – Class 3A thread fit ensures tight, vibration-resistant connections, reducing the risk of loosening in dynamic environments.
• Corrosion-Resistant Black Oxide Finish – Provides durable protection against rust and wear, extending service life in harsh industrial conditions.
• Knurled Head for Enhanced Grip – The knurled socket head allows for easy manual adjustment and secure tool engagement, improving installation efficiency.
• Long, Accurate Shoulder for Precise Alignment – The 7" shoulder with tight diameter and length tolerances ensures consistent component spacing and smooth rotational movement.
• High-Strength Alloy Steel Construction – Offers Rockwell C32 hardness for superior durability and resistance to deformation under heavy loads.
• Broad Regulatory Compliance – Meets ASME B18.3 specifications and is RoHS 3/REACH compliant, ensuring safety and environmental standards are upheld.

Professional Applications & Engineering Value

This 3/8"-16 UNC shoulder screw is engineered to address critical alignment and load distribution challenges in industrial machinery. The alloy steel core, combined with a black oxide finish, resists corrosion and wear in demanding environments such as automation systems, pivoting mechanisms, and precision fixtures. The 7" shoulder length provides a stable bearing surface, minimizing misalignment and reducing wear on mating components. With a Class 3A thread fit and knurled socket head, it ensures secure, repeatable assembly—ideal for applications requiring high tensile and shear strength, such as robotics, conveyor systems, and heavy-duty equipment mounts.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 standards, with a Class 3A thread fit for precise engagement. Key dimensional tolerances include a shoulder diameter of -0.004" to -0.002" and shoulder length of -0.005" to 0.005". It is manufactured from alloy steel under ASTM A574 and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability.