S-94705A833 1 1/4"-8 x 3 3/4" ASTM A193 Steel Heavy Hex Head Screws for High-Pressure Applications

Key Features & Benefits at a Glance

• Exceptional tensile strength of 125,000 PSI provides reliable performance in high-stress industrial environments, reducing the risk of fastener failure.
• ASTM Grade B7 material with Rockwell C35 hardness ensures superior durability and resistance to deformation under heavy loads and extreme conditions.
• Fully threaded 1 1/4"-8 UN fine thread design offers maximum grip and uniform stress distribution, enhancing joint integrity in critical assemblies.
• Class 2A thread fit guarantees precise, easy assembly and disassembly while maintaining secure fastening without galling or seizing.
• External hex drive and 2" head width allow for high-torque application with standard tools, speeding up installation in tight spaces.
• Right-hand thread direction and fine thread spacing deliver superior vibration resistance and improved clamping force in dynamic machinery.
• 3 3/4" length and robust steel construction provide versatility for thick-section connections, supporting long-term service in demanding applications.

Professional Applications & Engineering Value

This high-strength hex head screw is engineered to address critical challenges in heavy-duty mechanical systems, where vibration, high pressure, and thermal cycling are common. The ASTM Grade B7 steel composition, combined with Rockwell C35 hardness, ensures resilience against fatigue and corrosion, making it ideal for pressure vessels, valves, and structural assemblies. The fully threaded 1 1/4"-8 UN fine thread with Class 2A fit enables precise alignment and uniform load distribution, minimizing stress concentrations that lead to joint failure. By incorporating an external hex drive and right-hand thread, it simplifies maintenance and reduces downtime in industrial settings, offering a reliable fastening solution that meets rigorous ASTM A193 specifications for performance and safety.

Specification Summary & Compliance

This hex head screw features a 1 1/4"-8 UN fine thread with Class 2A thread fit for precise dimensional accuracy and ease of assembly. It complies with ASTM A193 specifications for high-temperature service and is manufactured from steel with a tensile strength of 125,000 PSI and hardness of Rockwell C35. The product adheres to industry standards for heavy-duty mechanical fasteners, ensuring consistent quality and reliability in applications requiring robust performance.