Китайский производитель центробежных насосов
Китайский производитель центробежных насосов
The impeller of a regenerative turbine pump is a uniform-thickness disc with many radial small vanes on both sides of its outer edge. On the pump casing, corresponding to the vanes, there is an annular flow passage of constant cross-section, which is divided by a tongue into suction and discharge sides connected respectively to the suction and discharge pipelines of the pump.As the liquid inside the pump rotates with the impeller, it generates a certain centrifugal force, is thrown outward into the annular passage in the casing, and is forced to flow back under the restriction of the passage shape, re‑entering the next vane channel from the root of the vanes. Therefore, the motion trace of the liquid between the vanes and the annular passage is a forward spiral relative to the stationary pump casing, and a backward spiral relative to the rotating impeller. The regenerative turbine pump gets its name from this vortex motion of the liquid.Liquid can enter between the vanes multiple times continuously to gain energy until it is discharged from the outlet. The operation of a regenerative turbine pump is somewhat similar to that of a multistage centrifugal pump, but it has no energy conversion device such as a volute or guide vanes as in centrifugal pumps.Regenerative turbine pumps transfer energy to the liquid mainly through multiple continuous impingements, enabling them to develop relatively high pressure. During energy transfer, considerable energy loss occurs due to repeated liquid impacts, resulting in relatively low pump efficiency, generally 20% to 50%.
Regenerative turbine pumps are only suitable for applications requiring low flow rate (1–40 m³/h) and high head (up to 250 m), such as fire pumps, gasoline pumps for aircraft refueling trucks, small boiler feed pumps, etc.They can handle highly volatile and gas‑containing liquids, but shall not be used for pumping viscous liquids with viscosity greater than 7 Pa·s or dirty liquids containing solid particles.
Features of regenerative turbine pumps: small flow rate, high head, and self-priming capability. They are suitable for conveying liquids similar to water without solid particles and with viscosity less than 5°E, such as gasoline, kerosene, alcohol, etc.Typical applications include water replenishment for small steam boilers, chemical industry, pharmaceuticals, high-rise building water supply, etc.Wetted parts can be made of stainless steel and other materials for handling corrosive liquids such as acids and alkalis.The allowable temperature range of the conveyed medium is -20 ℃ to +80 ℃.
Structurally, they can be classified into:single-stage, two-stage, multistage;close-coupled type, etc.
Applications of Regenerative Turbine Pumps
Type W single-stage close-coupled regenerative turbine pumps are used for pumping clean water or liquids with physical and chemical properties similar to water, at a temperature not exceeding 60℃.They are commonly used as boiler feedwater pumps and widely applied in shipbuilding, light industry, textile, chemical industry, metallurgy, machinery manufacturing, aquaculture, fixed fire pressure stabilization, heat exchanger units, agricultural long-distance sprinkler irrigation, and other fields.
The small size and light weight of regenerative turbine pumps offer significant advantages in marine applications.
They feature self-priming capability or can achieve self-priming with simple auxiliary devices.
With a steeply drooping head characteristic curve, they are insensitive to pressure fluctuations in the system.
Some regenerative turbine pumps allow gas-liquid mixture delivery, which is important for handling volatile liquids containing gas and high-temperature liquids with high vapor pressure.
They have a simple structure with easy casting and machining processes. Some parts can be made of non-metallic materials such as plastics and nylon molded impellers.
Disadvantages of Regenerative Turbine Pumps
Low efficiency, generally not exceeding 55%, with most pumps achieving only 20–40%, limiting their development toward high-power applications.
Poor cavitation performance.
Not suitable for highly viscous media. As liquid viscosity increases, head and efficiency drop sharply. Medium viscosity is limited to within 114 cSt.
Strict requirements for radial and axial clearances between the impeller and pump body create difficulties in manufacturing and assembly.
Only suitable for pumping clean liquids. Solid particles cause wear that increases clearances, degrading performance or disabling the pump.