S-8077A866 1/4"-28 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh industrial environments and chemical exposure
• Exceptional precision alignment provided by the 3/4" shoulder with tight diameter tolerance for reduced component wear
• High-strength performance delivering 70,000 psi tensile strength and 35,000 psi shear strength for demanding applications
• Premium thread accuracy with Class 3A UNF fine threads ensuring secure, vibration-resistant fastening
• Enhanced durability from black oxide finish that provides additional corrosion protection and reduced light reflection
• Secure installation with 5/32" hex socket drive and knurled head for superior torque application and grip
• Regulatory compliance meeting ASME B18.3 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

This 1/4"-28 UNF Class 3A shoulder screw delivers exceptional engineering value in precision assembly applications where alignment and corrosion resistance are critical. The 316 stainless steel construction combined with black oxide finish provides superior protection against corrosive environments, making it ideal for marine, chemical processing, and food equipment applications. The precisely machined 3/4" shoulder with tight diameter tolerance ensures accurate component positioning while reducing wear on mating parts. The socket head design with 5/32" hex drive and knurled texture allows for secure installation in confined spaces, while the Class 3A thread fit maintains vibration resistance in high-stress assemblies. These shoulder screws solve common engineering challenges of misalignment, corrosion failure, and installation accessibility in industrial machinery and precision equipment.

Specification Summary & Compliance

This precision shoulder screw features 1/4"-28 UNF Class 3A threads with fine thread spacing and right-hand thread direction. The shoulder maintains a diameter of 5/16" with tolerance of -0.004" to -0.002" and length of 3/4" with tolerance of -0.005" to 0.005". Manufactured to Rockwell B79 hardness with 70,000 psi tensile strength and 35,000 psi minimum shear strength. Fully compliant with ASME B18.3 specifications, RoHS 3 (2015/863/EU), and REACH (EC 1907/2006) environmental regulations.