S-91259A508 8-32 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Durability: Made from high-grade alloy steel with a Rockwell C32 hardness, ensuring long-lasting performance in demanding industrial environments.
• Superior Corrosion Resistance: Black oxide finish provides enhanced protection against rust and wear, extending the screw's service life.
• Precise Thread Engagement: Class 3A thread fit with UNC coarse threads ensures reliable, vibration-resistant connections for critical assemblies.
• Easy Installation and Grip: Knurled socket head with a standard hex drive (3/32") allows for secure tool engagement and reduces slippage during tightening.
• Accurate Shoulder Alignment: Features a 3/16" shoulder diameter with tight tolerances, providing consistent pivot points and spacing in precision mechanisms.
• High Load Capacity: Tensile strength of 140,000 psi supports heavy-duty applications without compromising structural integrity.
• Broad Compliance: Meets ASME B18.3 specifications and is RoHS 3 and REACH compliant, ensuring safety and environmental standards are upheld.

Professional Applications & Engineering Value

These 8-32 UNC thread shoulder screws are engineered to address common challenges in precision machinery, such as maintaining alignment and reducing wear in rotating assemblies. The alloy steel construction, combined with a black oxide finish, offers excellent resistance to corrosion and abrasion, making them ideal for automotive, aerospace, and industrial equipment. The Class 3A thread fit and coarse UNC thread design ensure quick assembly and reliable performance under vibration, while the knurled socket head enhances grip for efficient installation. By providing a sturdy shoulder length of 3/16", these screws serve as dependable pivots or spacers, minimizing part movement and improving overall system durability in high-stress environments.

Specification Summary & Compliance

This shoulder screw adheres to precise dimensional standards, including a Class 3A thread fit for superior accuracy and UNC coarse threads (8-32 size) to facilitate easy engagement. Manufacturing follows ASME B18.3 specifications, ensuring consistency and reliability. The product is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and suitable for global industrial use.