S-91286A330 1/2"-13 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 in high-stress applications, reducing the risk of fastener failure.
• Superior corrosion resistance with zinc-flake coating extends service life in harsh industrial environments, minimizing maintenance needs.
• High hardness rating (Rockwell C33) provides excellent wear resistance, maintaining thread integrity through repeated use.
• Precise Class 2A thread fit with UNC coarse threading enables quick assembly and secure fastening in various materials.
• Partially threaded design allows for controlled clamping force and prevents over-tightening in critical joints.
• External hex drive with 3/4" head width offers superior torque transmission for efficient installation with standard tools.
• Compliance with ASME B18.2.1 and SAE J429 Grade 8 ensures consistent quality and interchangeability in professional applications.

Professional Applications & Engineering Value

Engineered for demanding industrial environments, these Grade 8 hex head screws deliver exceptional performance where reliability is critical. The zinc-flake coated steel construction provides superior corrosion protection compared to conventional platings, making these 1/2"-13 UNC coarse thread fasteners ideal for outdoor equipment, heavy machinery, and structural assemblies exposed to moisture and chemicals. The partially threaded configuration ensures optimal stress distribution, preventing thread stripping in soft materials while maintaining high tensile strength capabilities. With their external hex drive design, these screws accommodate high torque applications common in construction, manufacturing, and automotive sectors, providing secure fastening solutions that withstand vibration and dynamic loads.

Specification Summary & Compliance

These hex head screws feature precise Class 2A thread fit with 1/2"-13 UNC coarse threading and 2 1/2" length, manufactured to ASME B18.2.1 specifications and meeting SAE J429 Grade 8 requirements. The fasteners are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring they meet current industry standards for hazardous substance restrictions.