S-8077A843 1/4"-20 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
• Enhanced durability and wear resistance from the black oxide finish, providing long-lasting performance and reduced maintenance
• High load-bearing capability with 70,000 psi tensile strength and 35,000 psi shear strength for demanding applications
• Precise alignment and smooth rotation thanks to the 13/16" shoulder length with tight tolerances for reduced vibration
• Easy installation and removal using the 5/32" hex drive and knurled head for secure tool grip
• Reliable thread engagement with Class 3A fit and coarse 1/4"-20 UNC threads for quick assembly in various materials
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH for quality assurance and regulatory safety

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to address critical challenges in industrial settings, such as misalignment, corrosion, and mechanical stress. The black oxide finish enhances surface hardness and provides a protective layer against rust, making it suitable for automotive, machinery, and marine applications where moisture and chemicals are present. The 1/4"-20 UNC coarse thread ensures fast, secure fastening in soft materials or when rapid assembly is required, while the 13/16" shoulder acts as a precise pivot or spacer, reducing wear on moving parts. With a Rockwell B79 hardness and high tensile strength, it withstands heavy loads and repetitive motion, minimizing downtime and maintenance costs in precision engineering and heavy-duty equipment.

Specification Summary & Compliance

This shoulder screw features precise dimensions, including a shoulder diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005", ensuring consistent fit in Class 3A thread applications. It adheres to ASME B18.3 standards for dimensional accuracy and performance, and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, guaranteeing safety and environmental responsibility in industrial use.