S-90324A136 5/16"-18 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 18-8 stainless steel construction, ideal for harsh industrial environments and reducing maintenance costs.
• Superior torque transmission and non-slip grip from the knurled socket head and 3/16" hex drive, ensuring secure fastening even in high-vibration applications.
• Reliable left-hand thread engagement for specialized assemblies where reverse threading prevents loosening under counter-clockwise rotational forces.
• High mechanical strength and durability with a tensile strength of 70,000 psi and Rockwell B55 hardness, providing a robust and long-lasting fastening solution.
• Precision alignment and spacing offered by the 3/8" shoulder diameter, acting as a reliable pivot or bearing surface in mechanical linkages.
• Guaranteed thread fit and interchangeability through the Class 3A thread fit and UNC coarse thread standard, ensuring consistent performance and easy replacement.
• Compliance with global environmental standards including RoHS 3 and REACH, making it suitable for use in regulated markets and eco-conscious supply chains.

Professional Applications & Engineering Value

This left-hand thread shoulder screw is engineered to address critical challenges in motion control and assembly systems. The 18-8 Stainless Steel provides excellent resistance to rust and corrosion, which is vital for equipment in moist or chemically aggressive environments. The coarse UNC thread and Class 3A fit ensure rapid assembly and a secure, precise fit, reducing the risk of cross-threading. The integral 3/8" shoulder diameter serves as a precise locating datum or bearing surface, preventing axial movement and misalignment in rotating assemblies like pivots, levers, and guide mechanisms. The knurled socket head with a hex drive allows for high-torque installation without stripping, making it a reliable choice for industrial automation, machinery, and heavy-duty equipment where vibration resistance and dimensional stability are paramount.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit for high-precision applications, ensuring tight tolerances and superior thread engagement. The manufacturing conforms to the UNC (Unified Coarse) thread standard with a left-hand direction. The shoulder diameter tolerance is maintained between -0.004" to -0.002", and the shoulder length tolerance is -0.005" to 0.005" for consistent performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for use in environments with strict environmental and safety standards.