S-91273A185 5/16"-18 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for harsh industrial environments
• Enhanced grip and torque transmission thanks to the knurled hex socket head design
• High mechanical strength with 70,000 psi tensile and 35,000 psi shear strength for demanding applications
• Precise component alignment enabled by the 4" shoulder length with tight tolerances
• Reliable and quick assembly with coarse UNC threads and Class 2A fit for consistent fastening
• Durable, long-lasting performance backed by Rockwell B55 hardness
• Compliance with global standards including RoHS 3 and REACH for safe, regulated use

Professional Applications & Engineering Value

This 18-8 stainless steel shoulder screw is engineered to solve critical alignment and pivot point challenges in industrial machinery, automation systems, and precision equipment. The 4" shoulder length provides a stable, precisely machined bearing surface that prevents component misalignment and reduces wear on moving parts. The coarse 5/16"-18 UNC thread and Class 2A fit ensure rapid, secure installation in high-vibration environments, while the knurled hex socket head offers superior grip for torque tools, preventing cam-out during assembly. Its high tensile and shear strength makes it ideal for heavy-duty applications where reliability and durability are paramount.

Specification Summary & Compliance

This shoulder screw features a 5/16"-18 UNC coarse thread with Class 2A thread fit for standard tolerance. The shoulder diameter tolerance is -0.004" to -0.002", and the shoulder length tolerance is -0.005" to 0.005" for precise engineering applications. It is manufactured from 18-8 Stainless Steel with a hardness of Rockwell B55. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations.