S-91259A447 5/8"-11 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional Shear & Tensile Performance – With 140,000 psi tensile and 84,000 psi minimum shear strength, this screw withstands high-stress applications without failure.
• Precision Class 3A Thread Fit – Ensures tight, secure fastening with minimal backlash in demanding assemblies.
• Corrosion-Resistant Black Oxide Finish – Extends service life by protecting the alloy steel from rust in harsh industrial environments.
• Knurled Socket Head for Non-Slip Grip – Provides superior handling during installation, even with gloves or oily conditions.
• Accurate Shoulder Diameter & Length – Maintains consistent alignment and spacing for rotating parts or pivot points.
• High Hardness (Rockwell C32) – Resists wear and deformation under repeated loads, ensuring long-term reliability.
• Compliance with Major Standards – Meets ASME B18.3, RoHS 3, and REACH, guaranteeing quality and environmental safety.

Professional Applications & Engineering Value

This 5/8"-11 UNC shoulder screw is engineered to address critical alignment and load-bearing challenges in industrial machinery. The alloy steel construction, combined with a black oxide finish, offers superior corrosion resistance and durability in environments exposed to moisture, chemicals, or high friction. The precisely machined 3/4" shoulder diameter and Class 3A thread fit ensure exact positioning for components like bearings, gears, and linkages, reducing vibration and misalignment. Its high tensile and shear strength makes it ideal for heavy-duty applications in automotive, aerospace, and manufacturing equipment, where failure is not an option. The knurled head and hex drive facilitate quick, secure installation, saving time in assembly lines.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 specifications with a Class 3A thread fit for precise UNC threading. Dimensions include a shoulder diameter of 3/4" (tolerance: -0.004" to -0.002") and shoulder length of 5/8" (tolerance: -0.005" to 0.005"), ensuring consistent performance. It is manufactured from alloy steel under ASTM A574 and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, meeting environmental and safety standards for global industrial use.