S-90298A574 1/4"-20 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 through Class 3A thread fit and controlled shoulder diameter tolerance (±0.001")
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness for demanding applications
• Secure installation and removal with 5/32" hex drive socket and knurled head for enhanced grip
• Reliable coarse threading using 1/4"-20 UNC standard for faster assembly and reduced cross-threading risk
• Industry compliance assurance meeting ASME B18.3 specifications and environmental standards (RoHS 3, REACH)
• Optimized shoulder design with 1/4" shoulder length providing stable bearing surfaces for rotating components

Professional Applications & Engineering Value

This stainless steel shoulder screw delivers critical engineering solutions where precision alignment and durability are paramount. The 18-8 stainless steel material with passivated finish provides exceptional corrosion resistance for machinery operating in humid or chemical-exposed environments. The Class 3A thread fit ensures tight tolerances in assemblies requiring minimal backlash, while the knurled head and hex socket drive facilitate secure installation in confined spaces. These shoulder screws are engineered for precision applications including rotating assemblies, pivoting mechanisms, and bearing retention systems where the shoulder serves as a precise locating diameter. The coarse UNC threading enables rapid assembly in production environments while maintaining the 70,000 psi tensile strength necessary for high-stress industrial applications.

Specification Summary & Compliance

This precision shoulder screw features 1/4"-20 UNC coarse threads with Class 3A fit for superior alignment accuracy. Critical dimensions include shoulder diameter tolerance of -0.001" to 0.001" and shoulder length tolerance of -0.005" to 0.005". Manufactured to ASME B18.3 specifications with full compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring both mechanical precision and regulatory adherence for industrial applications.