S-91247A870 3/4"-10 x 12" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength, ideal for heavy-duty structural and machinery applications
• Superior corrosion resistance from zinc plating, extending service life in harsh industrial environments
• Reliable mechanical performance ensured by Grade 5 steel and Rockwell C25 hardness for consistent durability
• Optimized coarse UNC threading provides faster installation and better grip in wood and soft materials
• Secure external hex drive allows for high-torque tightening with standard tools, preventing stripping
• Precision Class 2A thread fit ensures smooth assembly and interchangeability with standard nuts
• Versatile partial threading offers both strong clamping force and adjustable positioning flexibility

Professional Applications & Engineering Value

This 3/4"-10 UNC Grade 5 steel hex head screw is engineered to address critical industrial fastening challenges where vibration resistance, structural integrity, and environmental durability are paramount. The coarse thread design minimizes cross-threading risks during high-speed assembly in construction equipment, heavy machinery frames, and structural steel connections. Its zinc plating provides a sacrificial layer against oxidation, making it suitable for outdoor installations and humid operational environments. The partial threading allows unthreaded shank sections to bear shear loads directly, preventing joint loosening under dynamic stresses. With a 12-inch length and external hex drive, it delivers robust clamping force for large-scale fabrication, bridgework, and industrial plant maintenance, reducing downtime and replacement frequency.

Specification Summary & Compliance

This fastener maintains Class 2A thread tolerance for consistent fit with standard UNC nuts and features a 3/4"-10 coarse thread with a minimum 2-inch threaded length. Manufactured to ASME B18.2.1 and SAE J429 Grade 5 specifications, it guarantees dimensional accuracy and mechanical performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and regulatory acceptance in global industrial supply chains.