S-94383A250 1/4"-20 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 shoulder screw provides reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior Corrosion Resistance: The black oxide finish enhances durability by protecting the alloy steel from rust and corrosion, extending service life in harsh industrial environments.
• Precision Thread Fit for Secure Assembly: Class 3A thread fit ensures tight, consistent engagement with mating parts, minimizing loosening and improving overall assembly reliability.
• Enhanced Grip and Handling: The knurled head texture offers improved grip during manual installation or removal, facilitating easier handling without compromising the socket head's integrity.
• High Hardness for Wear Resistance: Rockwell C32 hardness provides excellent resistance to wear and deformation, maintaining dimensional stability under repeated use.
• Wide Industry Compliance: Meets ASME B18.3 and ASTM A574 standards, ensuring compatibility and reliability in regulated applications, while RoHS 3 and REACH compliance supports environmental and safety requirements.
• Optimized Shoulder Dimensions for Alignment: Precision-machined shoulder with tight diameter and length tolerances ensures accurate component alignment and reduces misalignment issues in assemblies.

Professional Applications & Engineering Value

This 1/4"-20 shoulder screw is engineered to address common industrial challenges, such as component misalignment and fastener fatigue. Made from alloy steel with a black oxide finish, it resists corrosion in demanding environments like machinery, automotive, and aerospace assemblies. The UNC coarse thread and Class 3A fit provide secure fastening, reducing vibration-induced loosening. The socket head with hex drive allows for easy installation in confined spaces, while the knurled texture enhances grip. Ideal for pivots, axles, and guides, this screw ensures precise shoulder alignment, minimizing wear and extending equipment lifespan in industrial applications.

Specification Summary & Compliance

This shoulder screw features precise dimensions, including a thread size of 1/4"-20 with Class 3A thread fit and UNC coarse threading for reliable engagement. The shoulder diameter and length adhere to tight tolerances (e.g., shoulder diameter tolerance of -0.004" to -0.002") to ensure accuracy. It complies with ASME B18.3 and ASTM A574 manufacturing specifications, guaranteeing consistent quality. Additionally, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) standards, supporting environmental and safety regulations for industrial use.