S-90429A197 3/4"-16 x 5" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional Load-Bearing Capacity: With a tensile strength of 130,000 psi and Rockwell C37 hardness, this screw withstands extreme mechanical stresses, reducing the risk of failure in heavy-duty assemblies.
• Precise Thread Engagement: Class 3A thread fit ensures tight, reliable fastening with minimal backlash, enhancing joint integrity in vibration-prone environments.
• Optimized Drive Efficiency: The 1/2" hex drive allows for high-torque installation using standard tools, speeding up assembly while preventing cam-out.
• Secure Flush Mounting: The 82° countersink angle and flat head design enable a smooth, recessed fit, eliminating protrusions and improving safety in machinery.
• Durable Material Construction: Alloy steel composition offers superior resistance to wear and fatigue, extending service life in demanding industrial applications.
• Regulatory Compliance Assurance: Meets ASTM F835 specifications and is RoHS 3/REACH compliant, ensuring environmental safety and global supply chain acceptance.
• Versatile Thread Design: UNF fine threads provide increased clamping force and better resistance to loosening under dynamic loads compared to coarse threads.

Professional Applications & Engineering Value

This 3/4"-16 UNF flat head screw is engineered to address critical challenges in heavy machinery, structural frameworks, and high-vibration equipment. The alloy steel construction, combined with a Rockwell C37 hardness rating, ensures durability against shear and tensile forces, making it ideal for applications where fastener failure could lead to costly downtime. The Class 3A thread fit and fine thread spacing enhance grip strength in materials like steel or cast iron, reducing the need for frequent retightening. Its partial threading allows for precise clamp load distribution, while the 82° countersink angle facilitates seamless integration into angled surfaces, common in automotive or aerospace assemblies. By complying with ASTM F835, it guarantees consistent performance in industrial fasteners requiring high reliability.

Specification Summary & Compliance

This fastener adheres to Class 3A thread fit tolerances per UNF standards, ensuring precise thread engagement. It meets ASTM F835 specifications for mechanical properties and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances. The inch system dimensions, including a 5" length and 1/2" hex drive, are manufactured to consistent industrial benchmarks for interoperability.