S-91286A347 1/2"-13 x 4 1/2" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 PSI tensile strength, ideal for high-stress industrial assemblies.
• Superior corrosion resistance from zinc-flake coating, extending service life in harsh environments.
• High hardness rating of Rockwell C33 ensures minimal wear and deformation under repeated use.
• Reliable coarse UNC threading provides faster installation and reduced cross-threading risks.
• Optimized partial threading allows for precise clamping force control in varied material thicknesses.
• Grade 8 strength classification guarantees consistent performance for heavy machinery and structural applications.
• External hex drive design enables high-torque tightening with standard tools, improving assembly efficiency.

Professional Applications & Engineering Value

Engineered for demanding environments, this Grade 8 hex head screw combines high-strength steel and a zinc-flake coated finish to resist corrosion in industrial settings like construction, machinery, and transportation equipment. The 1/2"-13 UNC coarse thread and Class 2A thread fit ensure quick, secure fastening, reducing assembly time while maintaining alignment accuracy. With partial threading, it offers flexibility for applications requiring unthreaded shank sections to bear shear loads, making it a versatile choice for heavy-duty bolting where vibration resistance and long-term reliability are critical.

Specification Summary & Compliance

This screw adheres to ASME B18.2.1 and SAE J429 Grade 8 standards, with precise Class 2A thread fit and UNC coarse thread specifications. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity for global industrial use.