S-90044A529 5/16"-18 x 3 1/2" ASME B18.3, ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
• Corrosion-resistant black-oxide finish on alloy steel enhances durability and extends service life in harsh industrial environments.
• Precise Class 3A thread fit provides superior engagement and vibration resistance, minimizing loosening in dynamic assemblies.
• Standard hex socket drive allows for easy installation with common tools, improving assembly efficiency and reducing labor time.
• Full threading along the 3-1/2" length offers versatile fastening options and consistent clamping force across the entire shank.
• Rockwell C37 hardness rating ensures high wear resistance and maintains structural integrity under repeated loads.
• Compliance with ASME B18.3 and material standards guarantees consistent quality and interoperability in professional applications.

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw is engineered to address critical challenges in heavy-duty industrial settings, such as machinery assembly, automotive systems, and structural frameworks. The 5/16"-18 UNRC coarse thread design, combined with a Class 3A thread fit, ensures secure fastening even under high vibration and dynamic loads, preventing unintentional loosening. The corrosion-resistant black-oxide surface treatment protects against rust and chemical exposure, making it ideal for environments where moisture or contaminants are present. With a high tensile strength of 170,000 psi and Rockwell C37 hardness, it delivers reliable performance in applications requiring robust, long-lasting connections without compromising on precision or safety.

Specification Summary & Compliance

This socket head cap screw features a 5/16"-18 thread size with Class 3A fit and UNRC coarse threading, ensuring dimensional accuracy and compatibility with standard components. It is manufactured in accordance with ASME B18.3 specifications and meets ASTM A574 material requirements. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its adherence to environmental and safety standards for industrial use.