S-91274A196 1/4"-20 x 2 1/2" 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 zinc-flake coating extends service life in harsh industrial environments, minimizing maintenance and replacement costs.
• Precise Class 3A thread fit provides secure, vibration-resistant connections, enhancing assembly integrity and reducing loosening over time.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use and disassembly.
• Partially threaded design allows for controlled clamping force, ideal for applications requiring precise grip length and alignment.
• Hex socket drive enables easy installation in confined spaces with standard tools, improving assembly efficiency and reducing labor time.
• Compliance with major standards including ASME B18.3 and ASTM A574 ensures consistent quality and interoperability in professional settings.

Professional Applications & Engineering Value

This Socket Head Cap Screw is engineered for demanding industrial applications where reliability and durability are critical. The zinc-flake-coated alloy steel construction provides robust corrosion resistance, making it suitable for machinery, automotive assemblies, and outdoor equipment exposed to moisture and chemicals. The 1/4"-20 UNC coarse thread with Class 3A fit ensures quick assembly and high vibration resistance, reducing the need for frequent retightening in dynamic environments. Its partially threaded rod allows precise engagement in tapped holes or nuts, preventing cross-threading and distributing stress evenly. With a tensile strength of 170,000 psi and Rockwell C37 hardness, it withstands heavy loads and impact, ideal for construction, aerospace, and manufacturing sectors requiring high-strength fasteners that comply with ASME B18.3 and ASTM specifications.

Specification Summary & Compliance

This screw features a 1/4"-20 UNC thread with Class 3A fit for precise dimensional accuracy and a coarse thread spacing that facilitates rapid installation. It meets ASME B18.3 for socket head cap screws, ASTM A574 for alloy steel material properties, and ASTM B117 for salt spray corrosion testing. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, ensuring adherence to environmental and safety regulations for industrial use.