S-90602A218 5/16"-18 x 1 1/4" IFI 111, SAE J429 High-Strength Grade 8 Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 150,000 PSI ensures reliable performance in high-stress and heavy-duty applications, reducing the risk of fastener failure.
• Superior corrosion resistance provided by the zinc yellow-chromate plating extends service life in harsh or outdoor environments, minimizing maintenance needs.
• High hardness (Rockwell C32) offers excellent wear resistance and durability, maintaining thread integrity under repeated use and vibration.
• Precise Class 3A thread fit with UNC coarse spacing allows for easier, faster assembly and a secure, vibration-resistant connection.
• Integrated flange design eliminates the need for a separate washer, providing a larger bearing surface for improved load distribution and simplified installation.
• Compliance with SAE J429/IFI 111 specifications guarantees consistent quality, dimensional accuracy, and interchangeability for industrial and automotive applications.
• Fully threaded shank ensures maximum grip and holding power along the entire length, ideal for applications requiring strong clamping force.

Professional Applications & Engineering Value

This Grade 8 hex head screw, manufactured from zinc yellow-chromate plated steel, is engineered to address critical challenges in demanding industrial environments. Its high tensile strength and Rockwell C32 hardness make it suitable for heavy machinery, construction equipment, and automotive assemblies where structural integrity is paramount. The UNC coarse thread and Class 3A fit facilitate quick installation while resisting loosening under vibration, a common issue in dynamic applications. The flanged head distributes clamp load effectively, reducing surface pressure and preventing damage to connected materials. This combination of material properties and thread design ensures long-term reliability, making it an optimal choice for engineers and procurement specialists seeking durable, high-performance industrial fasteners that meet rigorous standards.

Specification Summary & Compliance

This fastener adheres to precise dimensional and performance criteria, including a Class 3A thread fit for tight tolerances and UNC coarse threading with a 5/16"-18 thread size. It is manufactured in compliance with SAE J429 and IFI 111 specifications, ensuring consistency and reliability. The product meets common industry requirements for material and performance, though specific declarations for RoHS or REACH should be verified per lot. The zinc yellow-chromate plating provides corrosion protection, aligning with typical industrial surface treatment standards for enhanced durability.