S-91264A619 3/8"-16 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity: With a tensile strength of 140,000 psi and minimum shear strength of 84,000 psi, this screw reliably handles high-stress applications without failure.
• Secure Vibration Resistance: Integrated nylon pellet thread locker maintains fastener integrity from -50° to 250°F, preventing loosening in dynamic or thermal cycling environments.
• Precision Alignment and Durability: The 1/2" shoulder diameter with tight tolerances ensures accurate component positioning and reduces wear in rotating assemblies.
• Corrosion-Resistant Protection: Black oxide finish provides a durable layer that resists rust and extends service life in industrial conditions.
• High-Strength Material Construction: Made from alloy steel with Rockwell C32 hardness, offering superior toughness and fatigue resistance for long-term use.
• Easy Installation and Removal: Socket head with 1/4" hex drive allows for straightforward tightening in confined spaces, improving assembly efficiency.
• Reliable Thread Performance: Class 3A UNC coarse threads ensure a precise, secure fit with reduced risk of cross-threading during installation.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical challenges in precision machinery and heavy-duty industrial equipment. The 3/8"-16 UNC coarse thread with Class 3A fit provides excellent engagement in high-vibration environments, while the 1/2" shoulder diameter maintains exact alignment for components like gears, bearings, and linkages. The black oxide finish enhances corrosion resistance, crucial for operations in humid or corrosive settings. Integrated nylon pellet thread locker secures fastenings against shock and thermal expansion from -50° to 250°F, making it ideal for automotive, aerospace, and manufacturing assemblies where reliability is paramount. Its 140,000 psi tensile strength ensures it can withstand extreme loads without deformation, reducing maintenance needs and downtime.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit and UNC coarse thread standards for precise tolerance. Shoulder dimensions include a diameter of 1/2" with tolerance of -0.004" to -0.002" and length of 1/2" with tolerance of -0.005" to 0.005". It conforms to ASME B18.3 and ASTM A574 manufacturing specifications, ensuring consistent quality. The product is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting environmental and safety regulations for global industrial use.