S-91236A599 5/16"-18 x 4" ASME B18.2.1, ASTM A307 Low-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc plating, extending service life in harsh industrial environments
• High tensile strength of 60,000 psi ensures reliable performance under heavy loads and vibration
• Class 2A thread fit provides consistent, easy assembly while maintaining secure fastening
• Partially threaded design offers optimal grip and clamping force for varied material thicknesses
• External hex drive and hex head enable quick installation with standard tools, reducing assembly time
• Coarse UNC threads deliver faster driving and superior resistance to loosening in wood and metal
• Compliance with ASME B18.2.1/ASTM A307 guarantees dimensional accuracy and mechanical reliability

Professional Applications & Engineering Value

These heavy-duty hex head screws are engineered to solve critical fastening challenges in construction, machinery, and structural assemblies. The steel material with zinc plating combats rust and corrosion, making them ideal for outdoor or high-moisture environments. With a 60,000 psi tensile strength and Rockwell B69 hardness, they withstand significant stress without failure. The partially threaded 5/16"-18 UNC coarse thread design ensures strong grip in both soft and hard materials, while the external hex drive allows for efficient torque application. Perfect for industrial applications requiring durable, compliant fasteners that meet rigorous standards.

Specification Summary & Compliance

This screw features a Class 2A thread fit per UNC standards, ensuring precise dimensional tolerance. It complies with ASME B18.2.1 and ASTM A307 specifications for mechanical properties and manufacturing consistency. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting environmental and safety regulations for global industrial use.