S-91327A146 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with nylon patch thread locker maintains secure fastening from -50° to 250° F, preventing loosening in dynamic applications
• Superior corrosion resistance from 18-8 stainless steel construction with passivated finish ensures long-term reliability in harsh environments
• Enhanced installation control through knurled socket head design provides superior grip and torque transmission during assembly
• Precision thread engagement with Class 3A thread fit guarantees consistent performance and reliable mating with threaded components
• High strength-to-weight ratio delivers 70,000 psi tensile strength and Rockwell B55 hardness for demanding mechanical applications
• Optimized shoulder design with precise diameter and length tolerances ensures accurate alignment and smooth rotational movement
• Industry compliance assurance meeting ASME B18.3 specifications and environmental regulations including RoHS 3 and REACH

Professional Applications & Engineering Value

This 1/4"-20 UNC shoulder screw delivers exceptional engineering value in precision assemblies requiring both structural support and rotational functionality. The 18-8 stainless steel construction with passivated finish provides reliable corrosion resistance for industrial equipment, automotive components, and machinery operating in challenging environments. The integrated nylon patch thread locker addresses critical vibration-induced loosening concerns in rotating assemblies, while the knurled socket head with 5/32" hex drive ensures secure tool engagement during installation. The precision-machined shoulder with tight diameter and length tolerances maintains accurate component alignment in pivot points, bearing mounts, and linkage systems, making it ideal for applications where both fastening and precise spacing are required.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit and UNC coarse thread specifications ensuring reliable engagement. The shoulder features precise dimensional control with diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005". This shoulder screw complies with ASME B18.3 manufacturing specifications and meets environmental standards including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, making it suitable for global industrial applications requiring certified components.