S-94705A815 1 1/8"-8 x 4 1/4" 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 superior load-bearing capacity and resistance to failure in high-stress applications.
• ASTM Grade B7 steel construction offers excellent durability and reliability for demanding industrial environments and high-temperature service.
• Class 2A thread fit ensures smooth, precise assembly and reliable engagement with mating components, reducing the risk of cross-threading.
• Partially threaded design allows for effective clamping over a specific grip length, providing enhanced joint stability and vibration resistance.
• External hex drive and hex head facilitate easy installation and high-torque tightening with common tools, speeding up assembly processes.
• Rockwell C35 hardness delivers excellent wear resistance and maintains fastener integrity under repetitive stress and harsh conditions.
• Fine thread spacing (8 UN) offers improved adjustment precision and superior holding power compared to coarse threads in specific applications.

Professional Applications & Engineering Value

This high-strength hex head screw is engineered to solve critical challenges in heavy-duty industrial and construction settings. Manufactured from ASTM A193 Grade B7 steel, it provides exceptional resistance to tension, fatigue, and elevated temperatures, making it ideal for pressure vessels, structural connections, and machinery assembly. The partially threaded configuration concentrates clamping force over the 1 3/4" grip length, preventing loosening from vibrations—a common issue in dynamic environments. With a right-hand UN fine thread and external hex drive, it ensures quick, secure installation, reducing downtime. This industrial fastener meets the rigorous demands of sectors requiring 125,000 PSI tensile strength and reliable performance under continuous load.

Specification Summary & Compliance

This fastener adheres to Class 2A thread fit tolerances for consistent, reliable mating. It conforms to ASTM A193 specifications for high-temperature or high-pressure service, ensuring material and manufacturing consistency. The 1 1/8"-8 UN fine thread follows standardized dimensions for compatibility. The product is designed to meet industry requirements for heavy-duty applications, with compliance focused on mechanical properties and dimensional accuracy as per referenced standards.