S-91259A484 5/16"-18 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional durability with alloy steel construction and 140,000 psi tensile strength for reliable performance in heavy-duty applications
• Superior corrosion resistance through black oxide finish, extending service life in harsh industrial environments
• Precision thread engagement with Class 3A fit and UNC coarse threads ensuring secure fastening and vibration resistance
• Enhanced grip and torque application from knurled socket head with hex drive design for easy installation
• Accurate component alignment through precisely machined shoulder with tight diameter and length tolerances
• High hardness rating of Rockwell C32 maintains structural integrity under repeated loads
• Industry compliance assurance meeting ASME B18.3 specifications for guaranteed dimensional accuracy

Professional Applications & Engineering Value

This alloy steel shoulder screw with black oxide finish provides critical solutions for precision machinery and industrial equipment requiring exact component positioning. The knurled socket head with hex drive enables high-torque installation while preventing slippage in confined spaces. Engineered with Class 3A thread fit and UNC coarse threads, it maintains secure fastening in high-vibration environments common in manufacturing automation, robotics, and power transmission systems. The precisely machined shoulder diameter and length with tight tolerances ensure accurate bearing surfaces and pivot points, eliminating misalignment issues in assemblies. With 140,000 psi tensile strength and corrosion-resistant finish, this shoulder screw delivers long-term reliability in demanding applications where precision and durability are paramount.

Specification Summary & Compliance

This shoulder screw features precision 5/16"-18 UNC threads with Class 3A fit for superior thread engagement. The shoulder maintains tight dimensional control with diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005". Manufactured in compliance with ASME B18.3 specifications and material standards per ASTM A574. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for industrial components.