S-90298A830 1/2"-13 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments.
• Exceptional thread precision with Class 3A fit and UNC coarse threads for reliable, vibration-resistant fastening.
• Accurate component alignment ensured by a 3" shoulder with tight ±0.005" length tolerance and ±0.001" diameter tolerance.
• Enhanced grip and torque application from the knurled head and 5/16" hex socket drive, preventing tool slippage.
• High mechanical strength with Rockwell B55 hardness, providing durability under heavy loads.
• Broad industry compatibility through compliance with ASME B18.3 standards for dimensional consistency.
• Environmental and safety assurance by meeting RoHS 3 and REACH regulations, supporting sustainable manufacturing.

Professional Applications & Engineering Value

This 1/2"-13 UNC shoulder screw is engineered to address critical alignment and load-bearing challenges in precision assemblies. The 18-8 stainless steel material, combined with a passivated finish, offers excellent resistance to corrosion and wear, making it suitable for machinery, automotive, and aerospace applications where exposure to moisture and chemicals is common. The 3" shoulder length with minimal tolerances ensures precise positioning of moving parts like gears and pulleys, reducing wear and maintenance needs. Its coarse UNC threads and Class 3A fit provide secure fastening in high-vibration environments, while the knurled head and hex socket drive facilitate easy installation and removal with standard tools, enhancing assembly efficiency and reliability in demanding industrial settings.

Specification Summary & Compliance

This shoulder screw adheres to tight dimensional standards, including a Class 3A thread fit for precise engagement and UNC coarse threading. The shoulder features a diameter of 5/8" with a tolerance of -0.001" to 0.001" and a length of 3" with a tolerance of -0.005" to 0.005", ensuring consistent performance. Manufactured in compliance with ASME B18.3 specifications, it also meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for global industrial use without hazardous substances.