S-91286A325 1/2"-13 x 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, minimizing the risk of fastener failure in critical assemblies.
• Superior corrosion resistance from the zinc-flake coating protects against harsh environmental conditions, extending service life and reducing maintenance needs.
• High hardness rating (Rockwell C33) provides excellent wear resistance, maintaining structural integrity through repeated use and high-stress applications.
• Coarse UNC threading enables faster installation and easier alignment, reducing assembly time and labor costs in industrial settings.
• Precision Class 2A thread fit ensures consistent engagement and secure fastening, preventing loosening due to vibration or dynamic loads.
• Partially threaded design offers optimal clamp force distribution, ideal for applications requiring precise joint compression without thread interference.
• Compliance with major standards including ASME B18.2.1, RoHS 3, and REACH guarantees product quality, safety, and environmental responsibility for global supply chains.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, this Grade 8 hex head screw addresses common challenges in construction, machinery, and structural assemblies where high tensile strength and corrosion resistance are critical. The zinc-flake coated steel construction provides long-lasting protection against rust and chemical exposure, making it suitable for outdoor equipment, automotive frames, and manufacturing plants. Its UNC coarse thread and external hex drive facilitate quick installation with standard tools, reducing downtime in production lines. The partially threaded configuration ensures secure clamping in bolted joints, preventing shear stress concentration and enhancing overall assembly reliability. By meeting ASME B18.2.1 specifications, it delivers consistent performance in high-vibration environments, ensuring operational safety and reducing maintenance intervals.

Specification Summary & Compliance

This fastener features a 1/2"-13 UNC coarse thread with Class 2A tolerance for precise fit and reliable engagement. It complies with ASME B18.2.1 manufacturing standards, ensuring dimensional accuracy and mechanical properties. The product is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, adhering to environmental regulations for hazardous substance restrictions. With a specified tensile strength of 150,000 psi and Rockwell C33 hardness, it meets the rigorous demands of Grade 8 fastener classifications for industrial use.