Why can the Pneumatic Diaphragm Pump automatically adjust the flow rate according to the back pressure and is suitable for conveying medium and high viscosity fluids?

The power system of the Pneumatic Diaphragm Pump is based on compressed air, which is completely different from the traditional pumps driven by motors. The operation of traditional pumps depends on a motor with a fixed speed, and its output power is basically constant. When the back pressure changes during the conveying process, the working state of the pump is easily affected. The pneumatic diaphragm pump uses compressed air as the power medium, introduces compressed air into the pump body through the air inlet, and uses air pressure to push the diaphragm to reciprocate. This power transmission method makes the operation of the pump directly related to the air pressure. When the back pressure changes, the air pressure balance in the pump also changes, which in turn prompts the diaphragm movement frequency and stroke to automatically adjust, and realize the adaptive change of flow rate. ​
Specifically, when the pipeline resistance of the pneumatic diaphragm pump conveying fluid increases, that is, when the back pressure increases, the original air pressure balance inside the pump body is broken. At this time, the compressed air entering the pump body will automatically adjust the force and frequency of pushing the diaphragm according to the pressure difference, the reciprocating speed of the diaphragm will slow down, and the amount of fluid delivered each time will be reduced accordingly, thereby reducing the overall flow rate; conversely, when the back pressure decreases, the pipeline resistance becomes smaller, the force of the compressed air pushing the diaphragm increases, the diaphragm movement speed increases, and the pump flow rate increases accordingly. This automatic adjustment mechanism based on the change of air pressure balance gives the pneumatic diaphragm pump the ability to operate stably under complex working conditions. ​
When conveying medium and high viscosity fluids, the advantages of pneumatic diaphragm pumps are more significant. Medium and high viscosity fluids have the characteristics of poor fluidity and high resistance. Traditional pumps often face many challenges when conveying such fluids. For example, when a centrifugal pump conveys high viscosity fluids, the viscosity of the fluid will increase the resistance of the impeller rotation, resulting in a significant decrease in the efficiency of the pump, and even "air binding" may occur, making it impossible to convey the fluid normally; although the gear pump can provide a certain pressure, when handling high viscosity fluids, the wear between the gear and the pump body will increase, shortening the service life of the equipment, and it is also difficult to accurately control the flow rate.​

The pneumatic diaphragm pump effectively overcomes these problems through its unique structural design and working mode. It adopts a double diaphragm structure inside. The diaphragm alternately sucks and discharges liquid under the push of compressed air. This working mode has a small shear force on the fluid and will not damage the molecular structure and physical properties of medium and high viscosity fluids. Moreover, the sealing performance between the diaphragm and the pump body is good, which can form a stable pressure chamber during the conveying process, and can ensure the smooth passage of the fluid even in the face of the resistance of high viscosity fluids. At the same time, because its flow rate can be automatically adjusted with the back pressure, when conveying medium and high viscosity fluids, it can automatically match the most suitable conveying flow rate according to the actual viscosity of the fluid and the pipeline resistance, ensuring the stability and continuity of fluid conveying. ​
In actual industrial production, these two characteristics of pneumatic diaphragm pumps have been widely used. In the food processing industry, the conveying of high viscosity materials such as chocolate sauce and peanut butter is a key link in production. These materials are not only high in viscosity, but also extremely sensitive to factors such as temperature and shear force during the conveying process. Any inappropriateness will affect the taste and quality of the product. With the characteristics of automatic flow adjustment and low shear force, the pneumatic diaphragm pump can automatically adjust the flow rate according to the accumulation of materials in the pipeline, ensuring that the materials are evenly and stably transported to each processing station without destroying the delicate texture and flavor of the materials. ​
In the chemical industry, many corrosive medium and high viscosity chemical raw materials need to be accurately transported. Pneumatic diaphragm pumps can choose suitable corrosion-resistant materials according to different chemical media, such as polytetrafluoroethylene diaphragms and stainless steel pump bodies, to ensure that there will be no leakage and corrosion problems when transporting highly corrosive fluids. At the same time, during the chemical reaction process, as the reaction proceeds, the pressure and fluid viscosity in the pipeline may change. The pneumatic diaphragm pump can adjust the flow rate in real time according to the back pressure to ensure that the chemical raw materials are transported in a precise proportion, providing guarantee for the smooth progress of the chemical reaction. ​
In the field of building materials, the transportation of high-viscosity building materials such as tile adhesives and putty is also inseparable from pneumatic diaphragm pumps. During the construction process, the construction environment and requirements are complex and changeable, and the pipeline length, height and viscosity of the materials will be different. Pneumatic diaphragm pumps can automatically adjust the flow rate according to the back pressure under different construction conditions, accurately transport construction materials to the designated location, and improve construction efficiency and quality. ​
In the sewage treatment industry, the transportation of medium and high viscosity materials such as sludge also faces many difficulties. Sludge contains a large number of solid particles and impurities, which are easy to block the pipeline, and the viscosity is high, making it difficult to transport. Pneumatic diaphragm pumps have a large flow channel, which can allow particles of a certain size to pass through, reducing the risk of blockage. At the same time, its automatic flow adjustment feature enables it to automatically adjust the flow rate according to the concentration of the sludge and the pipeline resistance when transporting sludge, ensuring the stable operation of the sludge conveying system. ​
From the perspective of equipment maintenance, these two characteristics of pneumatic diaphragm pumps also bring significant advantages. Because its flow rate can automatically adapt to changes in back pressure, it does not require frequent manual adjustment during the transportation process, reducing the workload of operators and the possibility of operating errors. Moreover, because it can effectively transport medium and high viscosity fluids, it avoids equipment failures caused by fluid blockage, wear and other problems, extends the service life of the equipment, and reduces the maintenance cost and maintenance frequency of the equipment.​
Although pneumatic diaphragm pumps perform well in automatic flow adjustment and conveying medium and high viscosity fluids, in actual applications, they also need to be reasonably selected and configured according to specific working conditions and needs. For example, it is necessary to select the appropriate material according to the chemical properties of the conveyed fluid, and determine the model and specifications of the pump according to the flow and head requirements. Only in this way can the advantages of pneumatic diaphragm pumps be fully utilized to achieve efficient and stable fluid delivery.