Pump selection basis

When selecting a pump, it is crucial to consider various aspects based on the technological process and water supply and drainage requirements. These include the liquid delivery volume, the device head, the liquid properties, the pipeline layout, and the operating conditions. By taking into account these factors, you can identify the most suitable pump type for your specific needs. For example, the liquid delivery volume should align with the required flow rate, while the device head should match the necessary pressure requirements. Additionally, the properties of the liquid, such as temperature, viscosity, and corrosiveness, can impact pump selection. Finally, the pipeline layout and operating conditions can affect the pump's efficiency, reliability, and lifespan. Therefore, it is essential to thoroughly assess each of these factors to make an informed decision when choosing a pump.

Flow rate is a significant factor in choosing the right pump as it directly affects the production and conveying capacity of the entire system. It's necessary to calculate the normal, minimum, and maximum flow rates while designing the process. When selecting a pump, it's better to consider the maximum flow rate while keeping the normal flow rate in mind. If there is no maximum flow rate, it's recommended to consider 1.1 times the normal flow rate as the maximum flow rate.

When selecting a pump, the required head is a crucial performance factor to consider in the device system. It is recommended to increase the head by 5%-10% during the selection process. This ensures accurate pump selection based on the given information.

The properties of liquids are diverse, including the medium name, physical properties, chemical properties, and other characteristics. Physical properties encompass various factors such as temperature, density, viscosity, solid particle diameter, and gas content in the medium. These variables play a crucial role in determining the head of the system, calculating the effective cavitation residual quantity, and selecting the appropriate pump type. On the other hand, chemical properties refer to the liquid medium's corrosiveness and toxicity, which are vital when choosing pump materials and determining which type of shaft seal is suitable. Having a good understanding of these properties is essential for ensuring efficient and safe liquid transportation.

The layout of the pipeline system plays a crucial role in ensuring efficient liquid delivery. The conditions of the pipeline system include factors such as the height, distance, and direction of liquid delivery. It also involves determining the lowest liquid level on the suction side and the highest liquid level on the discharge side, along with other factors like pipeline specifications, length, materials, and fitting specifications.

These parameters are vital in calculating the system head and checking the NPSH. It is essential to ensure that the pipeline system is designed optimally to ensure smooth and uninterrupted liquid flow. By taking into account all the necessary conditions and data, engineers can lay out a pipeline system that is effective, efficient, and reliable.

6. When operating a pump, there are various factors to consider, including the temperature at which it operates, the pressure exerted by saturated steam, the absolute pressure on the suction side, the container pressure on the discharge side, the altitude at which it operates, the ambient temperature, whether the operation is intermittent or continuous, and whether the pump is fixed or removable. These operating conditions play a significant role in determining the pump's performance and efficiency.