Многоступенчатые и одноступенчатые центробежные насосы: руководство покупателя

Опубликован в 2025/05/29

Are you always confused about pump selection for industrial water supply? How to choose between multi-stage centrifugal pumps and single-stage pumps? In industrial manufacturing, agricultural irrigation, urban water supply and other scenarios, the choice of pumps is often a key decision that affects the whole body – insufficient head will lead to insufficient water pressure, too small flow cannot meet production needs, cost overruns may disrupt the budget, and maintenance troubles will affect long-term operational efficiency. When many users face the choice of “multi-stage VS single-stage центробежный насос“, they are often confused by questions such as “how much head can be achieved?” “Which one is more economical for large flow” and “Is the later maintenance expensive?” Today’s in-depth comparison guide will help you thoroughly sort out the differences between the two from principles to scenarios, from parameters to costs, and find the most suitable pump type!

In-depth comparison of the principles, performance, cost and application scenarios of multi-stage centrifugal pumps and single-stage pumps, helping you quickly lock in the optimal solution of the “head-flow-budget” triangle! It can be used in a variety of typical scenarios such as high-pressure water supply, agricultural irrigation, industrial processes, etc. The six-step purchase guide and quick check of common problems provide you with the best pump selection solution.

What is a multi-stage or single-stage centrifugal pump?

Multistage centrifugal pump: It connects 2 or more impellers in series on the same shaft. The liquid first enters the first-stage impeller for pressurization, and then flows into the second-stage impeller through the guide vane, repeating the “pressurization-diversion” process, and finally achieving a superimposed lift. For example, a single-stage pump is like climbing a flight of stairs, while a multi-stage pump is like climbing multiple layers in succession, and each layer makes the water pressure “go up a level”.

А single-stage pump has only one impeller. When the motor drives the impeller to rotate at high speed, the liquid is sucked into the center of the impeller, and is thrown to the edge of the impeller under the action of centrifugal force. After one pressurization, it is directly discharged from the pump body. This “one-time molding” structure determines its characteristics: simple structure, short process, but limited pressurization capacity.

Application of multi-stage and single-stage centrifugal pumps

Applicable scenarios of multi-stage centrifugal pumps

Multi-stage centrifugal pumps achieve step-by-step pressurization by connecting multiple impellers in series. The core advantage is high head, which is suitable for scenarios requiring high pressure or long-distance transportation.

(1) High-pressure scenario: water supply for high-rise buildings. As the building height increases, it is necessary to overcome greater gravitational potential energy. Multi-stage centrifugal pumps can achieve high-pressure transportation of liquids.

(2) Industrial high-pressure processes: such as boiler water supply, chemical high-pressure reaction, oil field water injection, etc. Such scenarios require stable high pressure. Multi-stage pumps can avoid the inefficiency of single-stage pumps that require multiple series connection due to insufficient head by connecting impellers in series.

(3) High-altitude areas: The atmospheric pressure is low, and high-lift pumps are required to ensure the normal transportation of liquids. Multi-stage centrifugal pumps can provide sufficient pressure to overcome the low-pressure environment in high-altitude areas and ensure the stability of liquid transportation.

Applicable scenarios of single-stage centrifugal pumps

Single-stage centrifugal pumps have only one impeller, simple structure, and smooth flow. The core advantages are large flow and low head, which are suitable for scenarios with high requirements for cost and installation convenience, including:

(1) Large flow and low head water supply: such as agricultural irrigation and primary water supply in water plants. Single-stage pumps have higher efficiency than multi-stage pumps due to the lack of impeller series resistance.

(2) Limited space or mobile scenarios: small factory supporting, vehicle-mounted emergency water supply pumps, single-stage pumps are smaller in size than multi-stage pumps, and installation and maintenance are more flexible.

(3) Home and small commercial applications: such as home tap water boosting, small air conditioning circulation system, laboratory low-head liquid transportation, single-stage pumps are simple to operate, low in energy consumption, and can meet daily low-pressure needs.

Multistage vs. Single-stage Centrifugal Pumps: Which to Choose?

Lift and flow:

single-stage pumps are selected for low lift and large flow; multi-stage pumps are selected for high lift and high flow, and low lift and low flow. The lift of a single-stage pump is generally ≤125 meters, and that of a multi-stage pump is >125 meters.

Efficiency:

The operating point of a single-stage pump may be biased to the left, resulting in large efficiency losses; the operating point of a multi-stage pump is in the middle, resulting in higher efficiency. For example, when the flow rate is 8m³/h and the lift is 60m, the multi-stage pump has a normal specific speed and higher efficiency.

Operating point position:

the operating point of a single-stage pump is biased to the left, and the water self-circulation is prone to damage the mechanical seal; the operating point of a multi-stage pump is in the middle, the water flow is normal, and the life of the mechanical seal is extended.

Motor power

The operating point of a single-stage pump is at the left end of the curve, and the motor power is high; the operating point of a multi-stage pump is in the middle, and the power is relatively low.

Performance adjustment

When the single-stage pump curve has a hump or the working condition is at the left end, it is difficult to adjust the operating state; the multi-stage pump curve decreases monotonically, the working condition is in the middle section, and the flow rate can be accurately adjusted.

Cost and maintenance

The multi-stage pump has a complex structure, high price and annual maintenance fee; the single-stage pump has a simple structure and is easy to install and maintain. Multi-stage pumps are more economical in the long run under high pressure and large flow, and single-stage pumps have low maintenance costs in small-scale and low-head scenarios.

In short, whether to choose a multi-stage centrifugal pump or a single-stage pump, you must consider multiple factors such as head, flow, efficiency, cost, and scenario. Multi-stage pumps are suitable for high-head and high-pressure scenarios; single-stage pumps are more advantageous in large-flow and low-head scenarios. When choosing a pump, you need to weigh the pros and cons based on your needs. We are a professional multi-stage and single-stage центробежный насос manufacturer with rich experience and professional technology. Насосы Walker поддерживает индивидуальные насосы на основе информации о вашей шахте. Связаться с нами Больше подробностей!