S-91247A326 7/16"-20 x 2 3/4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior tensile strength of 120,000 PSI ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Zinc plating provides excellent corrosion resistance, extending service life in harsh industrial environments and reducing maintenance costs.
• Fine UNF threading (7/16-20) offers improved vibration resistance and better clamping force compared to coarse threads.
• Grade 5 steel construction with Rockwell C25 hardness delivers optimal balance of strength and durability for demanding applications.
• Partially threaded design with Class 2A thread fit allows for precise engagement and easier alignment during assembly.
• External hex drive with 5/8" head width enables high-torque installation using standard tools, improving installation efficiency.
• Compliance with major industry standards including ASME B18.2.1 and SAE J429 ensures consistent quality and interchangeability.

Professional Applications & Engineering Value

This Grade 5 steel hex head screw with 7/16-20 UNF fine threading is engineered to solve critical fastening challenges in industrial applications. The combination of 120,000 PSI tensile strength and Rockwell C25 hardness provides exceptional load-bearing capacity for machinery, structural assemblies, and heavy equipment where vibration resistance is crucial. The zinc plating surface treatment offers reliable protection against corrosion in demanding environments, while the partially threaded design ensures optimal stress distribution and prevents thread damage during repeated disassembly. These hex head screws are particularly valuable in automotive, construction, and manufacturing sectors where ASME B18.2.1 compliance and consistent performance under dynamic loads are essential requirements.

Specification Summary & Compliance

This fastener maintains Class 2A thread fit tolerance for consistent engagement and features 7/16-20 UNF fine threads with a minimum thread length of 1 1/8". Manufactured to ASME B18.2.1 specifications and meeting SAE J429 Grade 5 requirements, it ensures dimensional accuracy and mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, making it suitable for global industrial applications.