S-91259A125 5/8"-11 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 140,000 psi tensile strength and 84,000 psi shear strength for reliable performance in demanding applications.
• Enhanced corrosion resistance and reduced galling thanks to the black oxide finish, extending service life in harsh industrial environments.
• Precise alignment and reduced wear with a knurled head and standard shoulder fit, ensuring stable component positioning and smooth assembly.
• Superior thread engagement and vibration resistance from Class 3A UNC coarse threads, providing secure fastening in high-stress conditions.
• High durability and hardness with Rockwell C32 rating, maintaining structural integrity under repeated loads and impacts.
• Easy installation and removal using a standard 3/8" hex drive socket head, saving time and reducing tool wear.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety and environmental responsibility.

Professional Applications & Engineering Value

This 5/8"-11 UNC shoulder screw is engineered from alloy steel to address critical challenges in industrial assemblies, such as misalignment and component wear. The black oxide finish not only provides corrosion resistance but also minimizes friction in high-movement applications like machinery pivots and rotating shafts. With a coarse thread design and Class 3A thread fit, it ensures quick, secure installation in heavy-duty equipment, reducing the risk of loosening under vibration. The precise shoulder diameter and length tolerances allow for accurate positioning in jigs, fixtures, and automotive systems, enhancing overall engineering efficiency and longevity. Ideal for use in industrial fasteners for manufacturing and automation, this screw delivers consistent performance where precision and strength are paramount.

Specification Summary & Compliance

This shoulder screw adheres to tight dimensional tolerances, including a shoulder diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005", with a Class 3A thread fit for high precision. It meets ASME B18.3 specifications and is manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) standards, ensuring environmental safety and regulatory adherence.