S-90409A191 5/8"-18 x 3" IFI 111, SAE J429 High-Strength Grade 8 Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 psi tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance and durability through Grade 8 steel construction with Rockwell C32 hardness
• Enhanced vibration resistance provided by UNF fine threading and Class 2A thread fit for secure fastening
• Easy installation and removal with external hex drive and 15/16" head width for standard tool compatibility
• Improved load distribution through the integrated flange design, eliminating the need for separate washers
• Reliable industrial compliance meeting IFI 111/SAE J429 standards for quality assurance
• Environmentally responsible manufacturing with RoHS 3 and REACH compliance for global regulatory acceptance

Professional Applications & Engineering Value

This Grade 8 hex head screw delivers exceptional engineering value in demanding industrial environments where failure is not an option. The 5/8"-18 UNF fine threading provides superior resistance to vibration loosening compared to coarse threads, making it ideal for machinery, heavy equipment, and structural applications. The partially threaded design ensures precise clamping force concentration while the flanged head distributes load evenly across surfaces, preventing material deformation. Manufactured from high-strength steel with Rockwell C32 hardness, this fastener maintains integrity under extreme mechanical stress and repetitive loading conditions. The external hex drive accommodates standard industrial tools for efficient installation in confined spaces, reducing assembly time and labor costs in manufacturing, construction, and maintenance operations.

Specification Summary & Compliance

This heavy-duty fastener features precision Class 2A thread fit with 5/8"-18 UNF fine threading and right-hand thread direction. The 3" length includes a minimum thread length of 1-1/2" with partial threading and incorporates a flanged head measuring 1-21/64" in diameter. Manufactured to IFI 111 specifications where identified as SAE J429 compliant, this screw meets rigorous industrial standards. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant regarding substance restrictions, ensuring environmental regulatory adherence for global industrial applications.