S-90807A128 5/16"-18 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 140,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure in demanding applications.
• Precision Class 3A thread fit provides superior thread engagement and vibration resistance, minimizing loosening in dynamic assemblies.
• Black oxide finish offers enhanced corrosion resistance, extending service life in harsh industrial environments without compromising dimensional integrity.
• Knurled socket head with hex drive allows for secure tool grip and easy installation, even in confined spaces or with gloved hands.
• Alloy steel construction with Rockwell C32 hardness delivers excellent wear resistance and durability, maintaining dimensional stability over repeated use cycles.
• Standard shoulder diameter and length with tight tolerances ensure precise alignment and smooth rotation in bushing or bearing applications.
• Full compliance with RoHS 3 and REACH regulations guarantees environmental safety and suitability for global industrial supply chains.

Professional Applications & Engineering Value

This alloy steel shoulder screw is engineered to address critical alignment and load-bearing challenges in precision machinery. The 5/16"-18 UNC coarse threading with Class 3A fit ensures secure fastening in high-vibration environments like automotive assemblies, robotics, and conveyor systems. The black oxide finish provides a protective layer against rust and corrosion, making it ideal for applications exposed to moisture or chemicals. The knurled socket head combined with a hex drive facilitates quick installation and removal, reducing assembly time in production lines. With a shoulder diameter of 5/16" and controlled tolerances, it offers exact positioning for rotating components, eliminating misalignment issues in pivots, linkages, and bearing mounts. This screw delivers consistent performance in industrial equipment, ensuring operational reliability and reduced maintenance costs.

Specification Summary & Compliance

This shoulder screw adheres to UNC coarse thread standards with a Class 3A thread fit for precise engagement. Dimensions include a thread size of 5/16"-18, shoulder diameter of 5/16" (tolerance: -0.004" to -0.002"), and shoulder length of 1 1/2" (tolerance: -0.005" to 0.005"). Manufactured from alloy steel with a hardness of Rockwell C32 and tensile strength of 140,000 psi, it meets rigorous industrial requirements. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for global markets.