S-91259A914 1/4"-20 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Superior strength and durability with 140,000 psi tensile strength and 84,000 psi shear strength, ideal for high-stress industrial applications.
• Precise shoulder alignment featuring a 5" shoulder length with tight tolerances for accurate component positioning and reduced assembly wear.
• Enhanced corrosion resistance thanks to the black oxide finish, providing reliable performance in demanding environments.
• Secure and easy installation with a knurled socket head and 5/32" hex drive, ensuring non-slip torque application and quick assembly.
• Consistent thread performance due to Class 3A thread fit and 1/4"-20 UNC coarse thread, offering reliable fastening and vibration resistance.
• High hardness and wear resistance from Rockwell C32 hardness, extending service life in repetitive motion applications.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety, quality, and environmental responsibility.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address common industrial challenges such as misalignment, component wear, and fastener failure in high-load scenarios. The 5" precision shoulder length with minimal tolerances ensures exact alignment in machinery, reducing stress on moving parts and prolonging equipment life. Its black oxide finish provides essential corrosion protection, making it suitable for humid or abrasive environments. The 1/4"-20 UNC coarse thread and Class 3A fit deliver secure fastening with excellent vibration resistance, ideal for assembly lines, automotive systems, and heavy-duty manufacturing. Combined with a knurled socket head for easy grip, this screw minimizes installation time and enhances reliability in industrial applications requiring repeated adjustments.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit and UNC coarse thread standards, with precise dimensions including a shoulder diameter tolerance of -0.004" to -0.002" and shoulder length tolerance of -0.005" to 0.005". It meets ASME B18.3 specifications and is manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for global industrial use.