S-91251A954 1 1/4"-7 x 20" 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.
• Superior corrosion resistance from the black-oxide finish prolongs service life in harsh industrial environments, minimizing maintenance needs.
• Precision Class 2A thread fit with UNC coarse threads provides easy assembly and secure fastening, saving time during installation.
• Partially threaded design allows for controlled clamping force and reduced thread galling, enhancing joint integrity.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining dimensional stability under heavy loads.
• Compliance with ASTM A574, RoHS 3, and REACH ensures material quality and environmental safety, supporting regulatory requirements.
• 7/8" hex drive and standard socket head enable efficient torque application with common tools, improving workflow efficiency.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to address critical challenges in heavy machinery, construction, and automotive assemblies where vibration and dynamic loads are common. The 1 1/4"-7 UNC coarse thread design resists loosening and provides rapid installation, while the partially threaded rod type concentrates stress away from the thread roots, reducing fatigue failures. With a 20" length and high tensile strength, it secures large structural components without compromising on durability. The black-oxide surface treatment adds a protective layer against rust and oxidation, making it ideal for outdoor or corrosive settings. By integrating ASTM A574 specifications, this fastener delivers consistent performance in demanding industrial applications, ensuring long-term reliability and reduced downtime.

Specification Summary & Compliance

This socket head cap screw features a 1 1/4"-7 UNC coarse thread with Class 2A thread fit for standard tolerance and easy assembly. It is manufactured in accordance with ASTM A574 for material consistency and performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety standards for hazardous substances.