S-90602A249 5/16"-18 x 3" 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 applications, reducing the risk of fastener failure.
• Superior corrosion resistance from zinc yellow-chromate plating extends service life in harsh industrial environments.
• High hardness rating (Rockwell C32) provides excellent wear resistance and maintains thread integrity during repeated use.
• Easy installation and removal with external hex drive design and coarse UNC threads that reduce cross-threading risks.
• Flanged head design distributes clamping force evenly, eliminating the need for separate washers in many applications.
• Precision Class 2A thread fit ensures consistent engagement and reliable performance in assembled components.
• Partially threaded shank allows for optimal grip range and controlled clamping force in various material thicknesses.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these Grade 8 hex head screws deliver exceptional performance where failure is not an option. The zinc yellow-chromate plated steel construction provides superior protection against corrosion in outdoor equipment, machinery, and structural assemblies. The UNC coarse thread design ensures rapid installation and superior vibration resistance in heavy machinery, construction equipment, and automotive applications. With partial threading and flanged head, these fasteners provide precise clamping control while eliminating washer requirements, streamlining assembly processes. The external hex drive offers high torque capability for secure installations in confined spaces, making them ideal for maintenance and manufacturing operations where reliability is critical.

Specification Summary & Compliance

This 5/16"-18 x 3" hex head screw features Class 2A thread fit tolerance for precise engagement and UNC coarse thread spacing for optimal performance. Manufactured to meet IFI 111/SAE J429 specifications for Grade 8 fasteners, ensuring consistent quality and dimensional accuracy. The partially threaded design provides controlled clamping with minimum thread length of 7/8". Compliant with industry standards for heavy-duty applications requiring 150,000 psi tensile strength and Rockwell C32 hardness.