S-93691A420 5/16"-18 MS51576-32, NASM51576 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.
• High mechanical strength offering 70,000 psi tensile strength and Rockwell B55 hardness for reliable, long-lasting performance under load.
• Precise alignment and stability ensured by a controlled 3/8" shoulder diameter and 5/8" shoulder length with tight tolerances for accurate component positioning.
• Easy installation and removal using a standard 3/16" hex drive socket head, providing secure torque application in confined spaces.
• Consistent thread engagement with a 5/16"-18 UNC coarse thread and Class 2A fit, facilitating quick assembly and reducing cross-threading risks.
• Compliance with stringent standards including MS51576, RoHS 3, and REACH, ensuring material safety and reliability for industrial applications.
• Durable right-hand thread design with coarse spacing for robust fastening in high-vibration settings, minimizing loosening over time.

Professional Applications & Engineering Value

This precision shoulder screw is engineered to address critical alignment and durability challenges in industrial machinery, automation systems, and precision instruments. Made from 18-8 stainless steel with a passivated finish, it resists corrosion and wear in demanding environments, while the UNC thread and Class 2A fit ensure reliable fastening. The precisely machined shoulder—with diameters and lengths held to tight tolerances—provides exact axial positioning for components like bearings, gears, and linkages, reducing assembly errors and maintenance needs. Ideal for applications requiring high tensile strength and consistent performance, this screw supports efficient production and long-term operational stability in sectors such as aerospace, automotive, and manufacturing.

Specification Summary & Compliance

The screw features a 5/16"-18 UNC thread with Class 2A dimensional accuracy and a precise shoulder diameter of 3/8" (tolerance: -0.001" to 0") and shoulder length of 5/8" (tolerance: 0" to 0.002"). It meets MS51576 manufacturing specifications and complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity for industrial use.