S-94705A849 1 1/4"-8 x 7 1/2" ASTM A193 Steel Heavy Hex Head Screws for High-Pressure Applications

Key Features & Benefits at a Glance

• Exceptional tensile strength of 125,000 psi ensures reliable performance under extreme loads, reducing the risk of fastener failure in critical applications.
• Superior material hardness (Rockwell C35) provides excellent resistance to wear and deformation, extending service life in demanding environments.
• Partially threaded design with a 4 1/2" grip length offers optimal clamping force and vibration resistance, ideal for heavy machinery and structural assemblies.
• Precision UN fine threads with Class 2A fit ensure smooth engagement and consistent torque application, minimizing assembly errors and improving joint integrity.
• Large 2" hex head with external drive allows for easy installation and high torque application using standard tools, speeding up maintenance and assembly processes.
• Compliance with ASTM A193 specifications guarantees material quality and manufacturing consistency, meeting rigorous industrial standards for safety and reliability.
• Robust steel construction combined with inch-system dimensions ensures compatibility with existing equipment and international engineering designs.

Professional Applications & Engineering Value

This Grade B7 steel hex head screw is engineered to address common industrial challenges such as high-stress fatigue, thermal cycling, and corrosive operational environments. The partially threaded configuration provides a secure grip across a 4.5-inch shank, distributing clamping force evenly to prevent joint loosening in vibrating machinery like pumps, compressors, and pressure vessels. With its UN fine thread and Class 2A tolerance, it ensures precise alignment and reduces the risk of cross-threading during installation, saving time and labor in assembly lines. The ASTM A193 compliance and high tensile strength make it a trusted choice for oil and gas, power generation, and construction sectors where fastener integrity is non-negotiable. Its external hex drive and durable steel material further support efficient maintenance and long-term operational stability.

Specification Summary & Compliance

This fastener adheres to Class 2A thread fit for consistent dimensional accuracy and features a 1 1/4"-8 UN fine thread with a 3-inch thread length. Manufactured in accordance with ASTM A193 specifications for high-temperature service, it meets ASTM Grade B7 requirements, ensuring material traceability and performance reliability. The product conforms to industry standards for heavy-duty applications, with full compliance to relevant material and safety regulations, including RoHS and REACH where applicable.