S-90298A851 5/8"-11 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 18-8 stainless steel construction and passivated finish, ensuring long-term reliability in harsh industrial environments.
• Precision alignment and reduced wear thanks to the 4" shoulder with tight ±0.005" length tolerance, providing stable bearing surfaces for rotating components.
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness, offering reliable load-bearing capacity for demanding applications.
• Secure, high-precision threading with Class 3A UNC thread fit, ensuring consistent engagement and vibration resistance in assembled parts.
• Easy installation and removal via the 3/8" hex socket drive and knurled head, allowing for efficient maintenance with standard tools.
• Compliance with industry standards including ASME B18.3, RoHS, and REACH, guaranteeing quality and environmental safety for global supply chains.
• Optimized for heavy-duty use with coarse 5/8"-11 UNC threads, providing quick assembly and high clamping force in machinery and equipment.

Professional Applications & Engineering Value

This stainless steel shoulder screw is engineered to address critical alignment and durability challenges in precision assemblies and industrial machinery. The 4" shoulder length with minimal tolerance (±0.005") ensures exact positioning of moving parts like gears, pulleys, and linkages, reducing misalignment and wear. Made from 18-8 stainless steel with a passivated finish, it resists corrosion from moisture, chemicals, and outdoor exposure, extending service life in applications such as conveyor systems, automation equipment, and heavy-duty manufacturing tools. The Class 3A thread fit and coarse UNC threading provide secure fastening under dynamic loads, while the knurled head and hex socket drive facilitate quick installation and maintenance, minimizing downtime in production environments.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 specifications, with precise dimensional controls including a shoulder length tolerance of -0.005" to 0.005" and diameter tolerance of -0.001" to 0.001". Threading follows UNC standards with a Class 3A fit for high accuracy. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety requirements for industrial use worldwide.