S-91274A152 1/4"-20 x 3/8" ASME B18.3, ASTM A574, ASTM B117 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.
• Superior corrosion resistance from the zinc-flake coating, ideal for harsh environments and extending service life.
• Precise Class 3A thread fit provides consistent engagement and vibration resistance, minimizing loosening in dynamic assemblies.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use.
• Coarse UNC thread design allows for quick assembly and disassembly, saving time in maintenance and production.
• Standard hex drive (3/16") ensures compatibility with common tools and secure torque application without stripping.
• Fully threaded right-hand design delivers maximum grip along the entire length, enhancing holding power in various materials.

Professional Applications & Engineering Value

This zinc-flake-coated alloy steel socket head cap screw is engineered to address critical challenges in heavy-duty industrial settings, such as machinery, automotive, and construction equipment. The 1/4"-20 UNC coarse thread and Class 3A fit provide superior resistance to vibration and loosening, ensuring long-term stability in high-load applications. The zinc-flake coating offers robust protection against corrosion, meeting ASTM B117 salt spray test standards, which is essential for outdoor or humid environments. Its 170,000 psi tensile strength and Rockwell C37 hardness make it ideal for assemblies requiring durability and reliability, reducing downtime and maintenance costs. This screw is a trusted solution for engineers seeking compliance with ASME B18.3 and ASTM A574 specifications, delivering consistent performance in demanding conditions.

Specification Summary & Compliance

This socket head cap screw features a 1/4"-20 UNC coarse thread with a Class 3A thread fit for precise dimensional accuracy and reliable engagement. It is manufactured in accordance with ASME B18.3 and ASTM A574 standards, ensuring consistent quality and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmental and safety requirements. Additionally, it meets ASTM B117 for salt spray testing, validating its corrosion resistance in industrial applications.