S-91268A360 1/2"-20 x 2 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 150,000 psi ensures reliable performance under extreme loads, reducing the risk of fastener failure in critical applications.
• Superior hardness (Rockwell C33) provides excellent resistance to wear and deformation, extending the service life of the screw in demanding environments.
• Grade 8 strength classification guarantees consistent high performance, making it ideal for heavy-duty industrial and machinery applications.
• UNF fine threading (1/2"-20) offers improved vibration resistance and a more secure fit compared to coarse threads, enhancing joint integrity.
• Partially threaded design allows for precise clamping force distribution, minimizing stress concentration and improving assembly stability.
• External hex drive and hex head facilitate easy installation and high torque application with standard tools, speeding up assembly processes.
• Compliance with ASME B18.2.1 and SAE J429 standards ensures dimensional accuracy and interoperability, supporting quality assurance in regulated industries.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address common industrial challenges such as high-stress fatigue and environmental degradation. Made from high-strength steel and featuring a 1/2"-20 UNF fine thread, it provides superior resistance to loosening under vibration, making it ideal for heavy machinery, automotive assemblies, and structural frameworks. The partially threaded design ensures that unthreaded portions bear load efficiently, reducing thread shear risks. With an external hex drive, it allows for quick, high-torque installations, streamlining maintenance and reducing downtime in industrial applications where reliability and durability are paramount.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including Class 2A thread fit for consistent assembly and ASME B18.2.1 / SAE J429 specifications. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material restrictions are met for global supply chain integration.