S-91264A798 5/8"-11 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Superior load-bearing capacity with 140,000 psi tensile strength and 84,000 psi shear strength for reliable performance in high-stress assemblies
• Enhanced corrosion resistance thanks to the black oxide finish, extending service life in harsh industrial environments
• Precision Class 3A thread fit ensures tight tolerances and secure fastening, minimizing vibration-induced loosening
• Integrated nylon pellet thread locker maintains clamp load integrity across a wide temperature range (-50° to 250°F)
• Knurled socket head design provides improved grip during installation, even with gloved hands or in oily conditions
• Alloy steel construction with Rockwell C32 hardness delivers excellent durability and wear resistance
• Standardized UNC coarse threading enables quick assembly and disassembly while resisting cross-threading

Professional Applications & Engineering Value

This high-performance shoulder screw addresses critical engineering challenges in precision machinery and heavy-duty equipment. The alloy steel core provides exceptional structural integrity for rotating assemblies, pivot points, and locating applications where shoulder diameter accuracy is paramount. The black oxide finish creates a protective barrier against rust and chemical exposure in manufacturing environments, while the nylon pellet thread locker eliminates the need for separate locking compounds in automated assembly processes. With UNC coarse threading and Class 3A thread fit, this fastener maintains precise alignment in high-vibration applications such as robotics, conveyor systems, and industrial automation equipment, reducing maintenance downtime and improving operational reliability.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit and precise shoulder diameter tolerance (-0.004" to -0.002"). Thread specifications conform to 5/8"-11 UNC coarse thread standards. Complies with ASME B18.3 dimensional requirements and material specifications per ASTM A574. Meets environmental regulations including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance for restricted substances.