S-91247A548 1/4"-20 x 1 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 industrial and construction applications, reducing the risk of fastener failure.
• Zinc plating provides excellent corrosion resistance, extending the service life of the screw in harsh environments and minimizing maintenance needs.
• Grade 5 classification and Rockwell C25 hardness offer a robust balance of strength and durability, ideal for heavy-duty mechanical assemblies.
• Coarse UNC threading with Class 2A fit allows for quick and secure installation, reducing assembly time while maintaining vibration resistance.
• Partially threaded design enables precise clamping force distribution, preventing joint loosening in dynamic load conditions.
• External hex drive and standard hex head facilitate easy installation with common tools, improving workflow efficiency on the job site.
• Compliance with ASME B18.2.1, SAE J429, RoHS 3, and REACH ensures adherence to industry standards and environmental regulations, providing peace of mind for professional procurement.

Professional Applications & Engineering Value

This Grade 5 hex head screw is engineered to address critical challenges in industrial fastening, where high tensile strength and corrosion resistance are paramount. The 1/4-20 UNC coarse thread with Class 2A fit ensures reliable engagement in materials like steel and aluminum, reducing the risk of cross-threading and stripping during assembly. The zinc plated finish protects against rust and oxidation in demanding environments such as construction sites, machinery, and automotive applications, while the partially threaded shank provides optimal grip length for secure joint integrity under vibration and dynamic loads. By meeting ASME B18.2.1 and SAE J429 specifications, this screw delivers consistent performance, minimizing downtime and enhancing safety in heavy-duty fastening scenarios.

Specification Summary & Compliance

This fastener features a 1/4"-20 UNC coarse thread with Class 2A thread fit for precise dimensional accuracy, ensuring compatibility with standard nuts and tapped holes. It adheres to ASME B18.2.1 and SAE J429 manufacturing standards, guaranteeing consistent quality and performance. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting environmental and safety regulations for use in various industries.