The Three Core Stages of Valve Manufacturing
Valve manufacturing is akin to precision surgery, where every step is critical to the final performance:
Casting/Forging: The valve body is formed using lost-foam or sand-casting techniques, while the valve core undergoes multiple rounds of high-temperature forging.
Machining: Five-axis CNC machine tools are employed to precision-finish the sealing surfaces, maintaining a flatness tolerance within 0.01 mm.
Heat Treatment: Valve stems undergo nitriding treatment, achieving a surface hardness exceeding HRC 60.
Specialized Processes for Key Components
The secret to a valve's longevity lies in the details:
Sealing Surface Hardfacing: Utilizes plasma hardfacing with cobalt-based alloy powder, capable of withstanding temperatures up to 800°C.
Valve Seat Lapping: Manual lapping, guided by an optical flatness tester, ensures a leak-free seal.
Corrosion Protection: The internal cavity features a sprayed coating with a thickness exceeding 200 μm, successfully passing a 2,000-hour salt spray test.
The Pinnacle of Assembly and Testing Expertise
Assembling the finished product is like conducting a symphony:
Low-Temperature Assembly: Metal-seated valves are assembled in a -10°C environment to accommodate for thermal expansion.
Dynamic Testing: A computer-controlled hydraulic test bench simulates 100,000 open-and-close cycles.
Intelligent Inspection: Industrial endoscopes are used to inspect internal flow channels, while X-ray flaw detection is applied to critical welds.