S-91274A472 1/2"-13 x 2 3/4" 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 provided by zinc-flake coating extends service life in harsh industrial environments, minimizing maintenance needs.
• Precise Class 3A thread fit guarantees secure, vibration-resistant connections, enhancing assembly integrity and safety.
• High hardness rating (Rockwell C37) offers excellent wear resistance, maintaining dimensional stability under repeated use.
• Partially threaded design allows for optimal clamping force control, ideal for applications requiring specific grip lengths.
• Standard hex drive compatibility with 3/8" drive tools enables quick installation and removal, improving workflow efficiency.
• 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 to address critical challenges in heavy-duty industrial applications, such as machinery assembly, automotive systems, and construction equipment. The zinc-flake-coated alloy steel construction provides robust protection against corrosion and chemical exposure, significantly extending component lifespan in demanding environments. With its 1/2"-13 UNC coarse thread and Class 3A fit, it delivers superior clamping force and vibration resistance, preventing loosening under dynamic loads. The partially threaded rod design allows for precise engagement in tapped holes or with nuts, reducing stress concentration and improving joint reliability. Ideal for use where high tensile strength and durability are paramount, this fastener ensures long-term performance in applications ranging from precision instruments to structural frameworks, supported by compliance with industry-leading specifications.

Specification Summary & Compliance

This socket head cap screw adheres to Class 3A thread fit tolerances per UNC standards, ensuring precise engagement and consistent performance. Manufacturing complies with ASME B18.3 for dimensional accuracy and ASTM A574 for material properties, while corrosion resistance is validated per ASTM B117. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, guaranteeing environmental safety and suitability for global industrial supply chains.