S-90298A628 5/16"-18 ASME B18.3 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
• Precise component alignment ensured by the 1-1/2" shoulder with tight ±0.005" length tolerance for reliable assembly
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness for demanding applications
• Secure fastening and easy installation featuring Class 3A thread fit and 3/16" hex socket drive with knurled head
• Industry-standard compatibility with UNC coarse threads and compliance with ASME B18.3 specifications
• Enhanced durability and longevity through robust material properties and controlled shoulder diameter tolerance (±0.001")
• Environmental compliance assurance meeting RoHS 3 and REACH regulations for safe, sustainable use

Professional Applications & Engineering Value

This 5/16"-18 UNC shoulder screw is engineered to address critical alignment and wear challenges in precision machinery, automation systems, and rotating assemblies. The 1-1/2" shoulder length with minimal tolerance provides exact positioning for gears, bearings, and linkages, reducing misalignment and component wear. Manufactured from 18-8 stainless steel with a passivated finish, it resists corrosion in humid or chemical-exposed environments, extending service life. The Class 3A thread fit and coarse UNC threading ensure vibration-resistant connections, while the socket head with knurled texture allows for quick, tool-friendly installation in confined spaces. Ideal for OEM and MRO applications, this screw delivers reliable performance where dimensional stability and industrial durability are paramount.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit and UNC coarse thread standards for precise engagement. Shoulder dimensions include a diameter tolerance of -0.001" to 0.001" and length tolerance of -0.005" to 0.005", ensuring high dimensional accuracy. It conforms to ASME B18.3 manufacturing specifications and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, guaranteeing environmental safety and industry acceptance.