S-91286A394 1/2"-20 x 6" 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 Grade 8 classification and 150,000 psi tensile strength for critical structural applications
• Superior corrosion protection through zinc-flake coating that withstands harsh industrial environments
• Precise thread engagement with UNF fine threads and Class 2A fit ensuring vibration resistance and reliable fastening
• Heavy-duty construction featuring Rockwell C33 hardness for exceptional wear resistance and durability
• Optimized torque transmission via external hex drive and 3/4" head width for secure installation with standard tools
• Versatile partial threading allowing both clamping and alignment functions in complex assemblies
• Regulatory compliance assurance meeting ASME B18.2.1, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver engineering excellence where failure is not an option. The UNF fine thread configuration provides superior resistance to vibrational loosening in heavy machinery, automotive systems, and structural steel connections. With 150,000 psi tensile strength and Rockwell C33 hardness, these fasteners maintain integrity under extreme static and dynamic loads. The zinc-flake coated surface offers exceptional corrosion protection, extending service life in outdoor and chemically aggressive environments. The partially threaded design enables precise clamping force distribution while the external hex drive ensures reliable torque application during installation. These industrial fasteners solve critical challenges in construction equipment, manufacturing machinery, and transportation infrastructure where high-strength bolts must perform consistently under demanding conditions.

Specification Summary & Compliance

Manufactured to exacting ASME B18.2.1 specifications and SAE J429 standards, these hex head screws feature precision Class 2A thread fit with 1/2"-20 UNF fine threads and 6" length. The partially threaded configuration provides optimal performance with 1 1/4" minimum thread length. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations ensures these components meet global manufacturing requirements for hazardous substance restrictions.