S-8077A545 5/8"-11 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and black oxide finish, ideal for harsh industrial environments.
• Exceptional mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for reliable performance in heavy-duty applications.
• Precise thread engagement with Class 3A fit and UNC coarse threads ensuring secure, vibration-resistant fastening.
• Easy installation and removal featuring a 3/8" hex socket drive and knurled head for improved grip and torque application.
• Accurate alignment and spacing provided by the 4 1/4" shoulder with tight tolerances for consistent assembly in machinery and pivots.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH for safe, regulated use in global markets.
• Durable wear resistance with Rockwell B79 hardness, extending service life in high-stress applications.

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to address critical challenges in industrial settings, such as corrosion from chemicals or moisture and mechanical stress from heavy loads. The black oxide finish enhances surface durability and reduces galling, while the UNC coarse threads and Class 3A thread fit provide reliable fastening that resists loosening under vibration. Commonly used in machinery assemblies, pivoting mechanisms, and precision equipment, the shoulder screw ensures accurate component alignment with its precisely machined shoulder, minimizing wear and maintenance downtime. Its high tensile and shear strength makes it suitable for demanding applications in automotive, aerospace, and manufacturing industries, where failure is not an option.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 specifications, with a Class 3A thread fit for precise tolerance and a shoulder diameter tolerance of -0.004" to -0.002". It meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance standards, ensuring environmental safety and regulatory acceptance. The design includes a 5/8"-11 UNC coarse thread and standard shoulder fit, providing consistent performance in industrial fastening applications.