Heavy Duty Industrial Dual Plate Check Valve

Heavy-duty industrial dual plate check valves are non-return valves specifically designed for high-pressure and large-flow applications. Featuring a dual-disc split design and a heavy-duty valve body, they are well suited for demanding industrial environments such as petrochemical processing, power generation, and metallurgy. Driven by the pressure of the flowing medium, the two valve discs open and close synchronously to ensure one-way flow control, offering the key advantages of reliable sealing, strong impact resistance, and high flow efficiency.

The structural design focuses on suitability for heavy-duty service. The valve body is manufactured from high-strength materials such as WCB/WCC cast steel and WC6/WC9 chromium–molybdenum alloy steel, produced through integral forging or thick-wall casting. The wall thickness complies with API 6D and ASME B16.34 standards, providing excellent pressure resistance and deformation resistance to withstand high-pressure impacts and frequent operating cycles in heavy industrial applications. The dual discs are made from austenitic stainless steel or wear-resistant alloy materials, with sealing surfaces overlay welded with Stellite 6 or hardfacing alloys (hardness ≥ HRC 58), offering outstanding wear and corrosion resistance. The symmetrical dual-disc design balances forces evenly and reduces opening and closing impact.

The valve seat adopts a metal hard-sealing structure combined with a spring preloading mechanism, ensuring tight contact between the dual discs and the seat. Leakage performance meets ANSI B16.104 Class V requirements. The disc shaft undergoes quenching, tempering, and nitriding treatment, and together with graphite packing, ensures leak-free operation. Built-in damping springs slow down the closing speed, effectively suppressing water hammer.

Key technical parameters include nominal sizes from DN50 to DN1200 (2"–48"), pressure ratings from PN16 to PN420 (Class 150 to 2500 LB), and an operating temperature range of –29 °C to 550 °C. Special high-temperature versions made from Inconel alloys can withstand extreme temperatures up to 650 °C. Connection types include flanged ends (in accordance with ASME B16.5 and GB/T 9113) and butt-welded ends, making the valve compatible with heavy industrial piping systems. Manufacturing and testing strictly follow standards such as API 598, GB/T 12224, and BS 1868, including shell hydrostatic tests, seat leakage tests, and non-destructive examinations (UT/RT), ensuring compliance with the safety requirements of heavy industrial service.

In terms of performance, the valve offers three major advantages. First, it provides high load-bearing capability: the heavy-duty body and dual-disc structure are well suited for high-pressure, large-flow conditions, ensuring long-term operation without deformation. Second, it delivers efficient opening and closing: the synchronized motion of the dual discs results in low operating resistance, with response speed approximately 30% faster than that of single-disc check valves. The flow resistance coefficient is ≤ 0.4, resulting in low pressure drop. Third, it offers strong impact resistance and durability: the damping springs and symmetrical force distribution reduce water hammer, while the wear-resistant sealing surfaces significantly extend service life—by approximately two to three times compared with conventional check valves. These valves are suitable for media such as crude oil, natural gas, steam, and high-temperature oils, and are typically applied in refinery catalytic units, main steam pipelines of thermal power plants, long-distance oil and gas transmission lines, and blast furnace gas pipelines in metallurgical plants, effectively preventing reverse flow that could cause equipment damage and system shutdowns.