Multistage Pumps

Multistage pumps are type of centrifugal pump that consists of two or more impellers mounted on a single shaft. These impellers are arranged in series within the pump casing. Each impeller stage adds a certain amount of pressure to the fluid being pumped. The design allows the pump to achieve high pressure output, making it suitable for applications where fluids need to be transported over long distances or to elevated heights.

Type:
Multistage pumps are available in many types, as listed below：
Horizontal multistage centrifugal pump
1.Multi-stage impeller structure: Multiple impellers are installed in series on the same shaft. Each stage of the impeller can increase the energy of the liquid, thereby achieving a higher head. The impeller is usually single-suction, that is, the liquid enters from one side of the impeller.
2.Segmented pump body: The pump body consists of multiple parts such as the water inlet section, the middle section, and the water outlet section. The sections are connected by bolts, which is convenient for manufacturing, installation and maintenance. This structure can adjust the number of pump stages by increasing or decreasing the number of middle sections according to different head requirements.

ZD self-balancing horizontal multistage centrifugal pump
1.ZD multistage pumps are generally used to transport clean water with a temperature of ≤105℃ or other liquids with physical and chemical properties similar to clean water.
2.ZD multistage pumps can be used to transport hot water, oils, corrosive or abrasive media with a temperature of ≤210℃ or even ≤225℃.
3.The pH value is generally between 6-8.

DG high pressure multistage boiler feed pump
1.Industrial boiler field: widely used in water supply systems of various industrial boilers, such as steam boilers and hot water boilers in thermal power plants, chemical plants, steel mills, paper mills, etc.
2.Urban heating system: can be used for hot water circulation and water replenishment in urban centralized heating systems.

D Urban water supply and drainage multistage pump
1.can delivery water to higher buildings or farther areas in the cityat a certain speed.
2. it can also provide a larger flow rate to meet the needs of large-scale water supply and drainage in the city.
3.during the peak period of urban water supply, it can ensure sufficient water supply; in terms of drainage, it can also quickly drain a large amount of accumulated water in heavy rain and other situations.

DY multistage pump for oil
1.The flow rate range of DY multi-stage oil pump is generally 3~350m³/h, and the head range is 13~400m.
2.This type of pump can convey temperature between - 20℃~105℃, viscosity less than 120 Centistokes of oily liquid can adapt to the common oil temperature and oil viscosity range in the petrochemical industry, ensuring the stable operation of the pump under different working conditions.

MD neutral mine multistage pump
1.MD mining multistage centrifugal pump is mainly used to transport neutral mineral water and other similar sewage with solid particle content not more than 1.5%.2.
2. The medium particle size should be less than 0.5 mm and the temperature of the delivery medium should not be more than 80℃. It is suitable for steel mills, mine drainage, sewage transportation and other occasions.
3.Flow rate: generally 3.7-1350m³/h,
4.Head: ranges from 17-1800m

Features:
1. Low NPSHr and dynamically balanced rotating parts
2. Various material options suitable for different liquid
3. Gland packing or mechanical seals on request
4. Centerline mounted casing is easy installation and maintenance
5. The balance disc and sleeve to protect shaft
6. Standard grease lubrication for temperature up to 140℃
7. Optimized diffuser construction for enhanced pump efficiency
8. No axial clearances when pump working and stop.
9. Provides optimum performance in high temperature service.

Application:
It adopts horizontal installation, has stable structure, small footprint and is easy to maintain. It is the preferred pump type in many large industrial projects. In the petrochemical industry, it is used to transport crude oil, refined oil and other media; in the mining industry, it can be used for mine drainage, etc., to pump underground water to the surface; in thermal power plants, it is used to transport circulating water, boiler feed water, etc.
How do multistage pumps work:
The working principle of a multistage pump is based on the centrifugal force generated by the rotation of the impellers. When the pump is started, the motor drives the shaft, which in turn rotates the impellers at a high speed. As the impellers spin, they impart kinetic energy to the fluid entering the pump.
The fluid enters the first impeller stage at the suction side of the pump. The centrifugal action of the first impeller accelerates the fluid radially outward, increasing its velocity and kinetic energy. This high-velocity fluid then exits the first impeller and enters the diffuser or volute of the first stage. The diffuser or volute is designed to convert the kinetic energy of the fluid into pressure energy by gradually slowing down the fluid and increasing its pressure.
After passing through the diffuser or volute of the first stage, the pressurized fluid enters the suction side of the second impeller stage. The process repeats in each subsequent impeller stage, with the fluid continuously gaining pressure as it passes through the series of impellers. Finally, the high-pressure fluid is discharged from the last impeller stage through the pump's discharge outlet.