S-91327A228 1/2"-13 Shoulder Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking: Permanent nylon patch thread locker prevents loosening under dynamic loads, maintaining clamp force in high-vibration environments.
• Superior corrosion resistance: 18-8 Stainless Steel with passivated finish offers excellent protection against rust and corrosion, extending service life.
• High-strength durability: 70,000 psi tensile strength and Rockwell B55 hardness ensure reliable performance under heavy mechanical stress.
• Precision alignment: 1" shoulder length with controlled diameter tolerance provides accurate component positioning and reduces bearing wear.
• Secure installation: Knurled head and 1/4" hex drive offer superior grip and torque transmission, preventing tool slippage.
• Wide temperature tolerance: Thread locker remains effective from -50° to 250°F, suitable for diverse operating conditions.
• Regulatory compliance: Meets RoHS 3 and REACH standards, ensuring safety and environmental responsibility in global markets.

Professional Applications & Engineering Value

This 18-8 Stainless Steel shoulder screw is engineered to solve critical assembly challenges in demanding industrial settings. The 1/2"-13 UNC Class 3A thread with coarse spacing ensures rapid installation and high load-bearing capacity, while the precision shoulder diameter maintains exact alignment in rotating machinery, conveyor systems, and precision instruments. The integrated nylon patch thread locker provides permanent resistance to vibration-induced loosening, eliminating the need for separate locking hardware. With its passivated finish enhancing corrosion resistance, this fastener delivers long-term reliability in manufacturing equipment, automotive assemblies, and outdoor applications where environmental factors and mechanical stress are concerns.

Specification Summary & Compliance

This shoulder screw features precision Class 3A thread fit per UNC standards, ensuring tight tolerances for secure fastening. The shoulder maintains a diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005" for consistent performance. Manufactured from 18-8 Stainless Steel with passivated finish, it complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, meeting international environmental and safety standards for industrial components.