S-91236A728 1/2"-13 x 4" ASME B18.2.1, ASTM A307 Low-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional Tensile Strength – With 60,000 psi tensile strength, this screw provides reliable holding power for demanding industrial applications, reducing the risk of fastener failure.
• Superior Corrosion Resistance – The zinc plating finish offers enhanced protection against rust and environmental degradation, extending service life in harsh conditions.
• Optimized Thread Design – Coarse UNC threads and Class 2A fit ensure quick assembly, secure fastening, and reduced cross-threading in a variety of materials.
• Robust Material & Hardness – Made from steel with Rockwell B69 hardness, it delivers excellent durability and resistance to wear under heavy loads.
• Convenient External Hex Drive – The hex head allows for easy installation and removal with standard tools, improving efficiency in maintenance and assembly operations.
• Partially Threaded Shank – This design provides unthreaded grip length for better clamp load distribution, ideal for structural and machinery fastening.
• Compliance with Industry Standards – Meets ASME B18.2.1 and ASTM A307 specifications, ensuring consistent quality, reliability, and interchangeability.

Professional Applications & Engineering Value

This 1/2"-13 UNC hex head screw is engineered to address critical fastening challenges in industrial applications such as machinery assembly, structural frameworks, and heavy equipment. The steel material and Rockwell B69 hardness provide the necessary toughness to withstand vibration and dynamic loads, while the zinc plating offers a protective barrier against moisture and chemicals, reducing maintenance needs. The coarse thread and Class 2A thread fit facilitate quick, secure installation in both metal and wood, minimizing assembly time and improving operational efficiency. Its partially threaded design ensures that the unthreaded portion bears the clamp load effectively, preventing loosening and enhancing joint integrity in high-stress environments.

Specification Summary & Compliance

This screw features a 1/2"-13 UNC coarse thread with Class 2A thread fit for precise dimensional accuracy and easy assembly. It is manufactured in accordance with ASME B18.2.1 and ASTM A307 standards, ensuring consistent performance and reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety and environmental responsibility for global supply chains.