S-90324A132 5/16"-18 Shoulder Screws

Key Features & Benefits at a Glance

• Superior Corrosion Resistance: Made from 18-8 Stainless Steel to withstand harsh environments, reducing maintenance and replacement costs.
• Exceptional Tensile & Shear Strength: Withstands up to 70,000 psi tensile and 35,000 psi shear loads, ensuring reliable performance in high-stress applications.
• Precision Class 3A Thread Fit: Guarantees tighter tolerances and a more secure, vibration-resistant connection compared to standard fits.
• Secure Anti-Loosening Design: Left-hand UNC coarse threads provide resistance to unintentional loosening in rotating machinery applications.
• Easy Installation & Removal: Hex socket drive and knurled head allow for a firm grip and straightforward tool engagement, speeding up assembly.
• Durable & Hardened Material: Rockwell B55 hardness ensures excellent wear resistance and long-term dimensional stability of the shoulder.
• Regulatory Compliance Assurance: Meets RoHS 3 and REACH standards, making it suitable for use in regulated industries and global markets.

Professional Applications & Engineering Value

This shoulder screw is engineered to act as a precise axle, pivot, or spacer in assemblies where rotational movement or precise alignment is critical. The 3/4" shoulder length provides a consistent bearing surface, eliminating the need for separate spacers and reducing component count. Manufactured from 18-8 Stainless Steel, it offers excellent corrosion resistance, which is vital for food processing, marine, and chemical industry equipment. The left-hand UNC coarse thread with a Class 3A fit is specifically designed for applications where standard right-hand threads would be prone to loosening from counter-clockwise motion, such as in certain types of motors, conveyor systems, and heavy machinery. This combination of precision, material strength, and specialized thread direction solves common challenges of part misalignment, corrosion-induced failure, and vibration-induced loosening.

Specification Summary & Compliance

This precision shoulder screw adheres to UNC thread standards with a Class 3A fit for superior thread engagement. The shoulder diameter is held to a tight tolerance of -0.004" to -0.002", and the shoulder length to -0.005" to 0.005". The manufacturing and material composition are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for demanding industrial and international applications.