S-91257A723 1/2"-13 x 2 3/4" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Maximum load-bearing capacity with 150,000 psi tensile strength, ideal for high-stress industrial applications
• Superior corrosion resistance through zinc yellow-chromate plating, extending service life in harsh environments
• Enhanced durability with Rockwell C33 hardness, maintaining structural integrity under repeated stress
• Secure fastening performance with Class 2A thread fit and UNC coarse threading for reliable engagement
• Easy installation and removal using standard external hex drive and 3/4" head width
• Partial threading design providing optimal grip length while reducing weight and material usage
• Full regulatory compliance meeting ASME B18.2.1, SAE J429, RoHS 3 and REACH standards

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver exceptional engineering value for heavy machinery, structural steel connections, and industrial equipment assembly. The zinc yellow-chromate plated steel construction provides superior corrosion protection in demanding environments, while the 1/2"-13 UNC coarse thread ensures rapid installation and vibration resistance. With 150,000 psi tensile strength and Rockwell C33 hardness, these fasteners maintain clamping force under extreme loads, preventing joint failure in critical applications. The partially threaded design concentrates strength where needed most, making them ideal for bolted connections requiring precise load distribution in construction, manufacturing, and heavy equipment maintenance.

Specification Summary & Compliance

This Grade 8 hex head screw features precise Class 2A thread fit with 1/2"-13 UNC coarse thread spacing and 2 3/4" length. Manufactured to ASME B18.2.1 and SAE J429 specifications, ensuring dimensional accuracy and performance reliability. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations for safe industrial use worldwide.