Factors affecting the efficiency of centrifugal pumps

Analyze the factors that affect the efficiency of centrifugal pump sets and propose improvement measures to improve the operational efficiency of centrifugal pumps and reduce equipment energy consumption.

Several factors affecting the efficiency of centrifugal pump sets

The efficiency of a centrifugal pump is the product of mechanical, volumetric, and hydraulic efficiency. The efficiency of a pump unit is the product of pump efficiency and motor efficiency. The main factors that cause low efficiency of centrifugal pump units are as follows.

The efficiency of the pump itself is the most fundamental impact. Under the same working conditions, the efficiency of pumps may differ by more than 15%.

2. The operating condition of a centrifugal pump is lower than the rated condition of the pump, resulting in low pump efficiency and high energy consumption.

3. The efficiency of the motor remains basically unchanged during operation. Therefore, choosing a high-efficiency motor is crucial.

The impact of mechanical efficiency is mainly related to design and manufacturing quality. After selecting the pump, the impact of later management is relatively small.

5. Hydraulic losses include hydraulic friction and local resistance losses. After a certain period of pump operation, it is inevitable to cause surface wear of components such as impellers and guide vanes, increase hydraulic losses, and reduce hydraulic efficiency.

6. The volume loss of a pump, also known as leakage loss, includes three types of leakage losses: impeller sealing ring, interstage, and axial force balance mechanism. The level of volumetric efficiency is not only related to design and manufacturing, but also to later management. After continuous operation of the pump for a certain period of time, due to friction between various components, the gap increases and the volumetric efficiency decreases.

7. Due to blockage of the filter cylinder, pipeline intake, and other reasons, the centrifugal pump is evacuated and idling.

8. Before starting the pump, employees do not pay attention to the preparation work before starting the centrifugal pump, and basic operating procedures such as warm-up pump, disc pump, and filling pump are not thoroughly executed, often causing cavitation of the pump, causing high pump noise, vibration, and low pump efficiency.