Non Positive Displacement Pump
Fluid handling is a crucial aspect in modern industrial and civil applications. And it is in this area that non-displacement pumps, as a key piece of equipment, are continually pushing the boundaries of fluid handling technology. From water supply systems to wastewater treatment plants, from oil extraction to chemical production, non-displacement pumps are ubiquitous and play a key role.
What is a non-Positive displacement pump?
A non positive displacement pump is a type of pump used for transferring fluids that works differently than a positive displacement pump. Volumetric pumps by changing the volume of the pump chamber to realize the liquid suction and discharge, such as piston pumps and gear pumps. Non positive displacement pump does not depend on the change of the pump chamber volume to realize the transmission of fluid.
Applications For Non Positive Displacement Pumps
- Water supply systems: Non positive displacement pumps are one of the most common pumps used in water supply systems for lifting and transferring tap water or industrial water.
- Wastewater treatment: They are capable of handling liquids containing solid particles, such as sewage, drainage, and industrial wastewater, and are commonly used in sewage treatment plants and drainage systems.
- Chemical Industry: Non positive displacement pumps are used in the chemical industry to convey various liquids and chemicals such as acids, alkalis, solvents, corrosive liquids etc.
- Agricultural Irrigation: Non positive displacement pumps are commonly used in agricultural irrigation systems for lifting and conveying water to meet the needs of agricultural irrigation and to improve crop yields.
- Construction Engineering: Non positive displacement pumps are used in construction engineering for water lifting, drainage, sewage and fire fighting systems, etc. to ensure the normal operation and safety of buildings.
Displacement and Non Positive Displacement Pumps
Displacement pumps and non positive displacement pumps are two different types of pumps, the main difference between them is the working principle and application scenarios.
Principle of work
Positive Displacement Pump: A positive displacement pump draws in and discharges liquid by changing the volume of the pump chamber. In each operating cycle, the change in the volume of the pump chamber causes the liquid to be sucked in, then compressed and discharged. Volumetric pumps have higher pressures and lower flow rates, and are suitable for applications with high pressure requirements, providing a stable flow and pressure output.
Nonpositive displacement pump: Non positive displacement pumps do not rely on changes in pump chamber volume to achieve the transfer of liquids, but rather the use of other principles, such as centrifugal force, vortex effect, etc. to transport fluids.Non positive displacement pumps are usually suitable for high flow, low pressure applications where the output pressure and flow rate are more restricted.
Advantages and Disadvantages Of Non Positive Displacement Pumps
Advantages
- Suitable for high flow scenarios: Non positive displacement pumps are usually suitable for high flow application scenarios, capable of efficiently transferring large quantities of liquids or gases.
- Simple structure: Simple structure reduces maintenance cost and time cost.
- Stable operation: does not rely on changes in the volume of the pump chamber to achieve fluid transfer, which is conducive to the stable operation of the system.
- Strong adaptability: The non positive displacement pump is suitable for a variety of different types of fluids, including liquids and gases, and has strong adaptability and versatility.
- No pulsation flow: can provide a relatively uniform flow, will not produce pulsation flow, suitable for the application of the flow stability requirements of the higher scenarios.
Disadvantages
- Not suitable for high pressure scenarios: For high pressure scenarios, non positive displacement pumps may be less suitable.
- Lower efficiency: Compared to some positive displacement pumps, non positive displacement pumps may be less efficient in some specific situations.
- Requires external energy for drive: Non positive displacement pumps usually require an external energy source (e.g. electricity or mechanical energy) for drive, and therefore may suffer in the absence of a stable energy supply.
Types of Non Positive Displacement Pumps
Centrifugal Pumps: Centrifugal pumps are one of the most common and widely used non positive displacement pumps. It generates centrifugal force by means of a rotating impeller, which draws liquid through the center of the pump and discharges it through the pump outlet. AOBL vertical multistage pumps are suitable for transferring liquids such as water, oil & chemicals, etc.
Screw pumps: Screw pumps utilize a rotating screw to convey liquid from the suction port of the pump to the discharge port. Eccentric screw pumps are suitable for conveying high viscosity liquids and liquids containing solid particles, such as petroleum, chemical and food industries.
Vortex pumps: Vortex pumps utilize the vortex effect to draw liquid in from the suction port of the pump and discharge it through the vortex effect. These pumps are suitable for handling liquids containing solid particles, such as sewage and wastewater treatment.
Chemical pumps: Chemical pumps are pumps specially designed to convey chemicals, corrosive liquids, solvents and corrosive media. Chemical pumps are widely used in chemical production, petrochemical, pharmaceutical industry and other fields, such as sulfuric acid, hydrofluoric acid, sodium hydroxide and so on.
Drive Pumps: Drive pumps are pumps used in industrial processes to transfer a variety of fluid media such as water, oil, chemicals, etc. MP Magnetic Drive Pumps offer high efficiency, stability and reliability for a wide range of industrial processes.
Summary
Non positive displacement pumps provide indispensable support to our lives and production as a key fluid transfer device, whether for water supply, drainage, irrigation or wastewater treatment.
AOBL is a pump manufacturer offering air operated diaphragm pumps, sanitary diaphragm pumps, filter press feed pumps and a range of pump accessories, contact us to be able to produce a customized solution for you.