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Understand more about Diaphragm Pump

Diaphragm pumps mainly use membranes to separate the liquid from the movable column and the pump cylinder. One side of the diaphragm pump’s internal structure is made of highly corrosive materials, while the other side contains oil or water. Its exterior is usually made of plastic, aluminum alloy, cast iron, stainless steel and other materials. Diaphragm pumps use power operation to change the flow of the medium in the pump by receiving the control signal from the regulator. Diaphragm pumps are suitable for use in various industries, such as clean water, high-strength acid liquids, and viscous liquids. The operation of the diaphragm pump is simple and the price is cheap.

How does a diaphragm pump works

Diaphragm pump is also known as a pneumatic diaphragm pump. It is a positive displacement pump, which mainly relies on the reciprocating movement of the diaphragm to change the volume of the working chamber. Its transmission methods can be categorized into hydraulic transmission, pneumatic transmission and mechanical transmission.

There is a centrally connected shaft in the two working chambers of the diaphragm pump. This shaft passes through the center of the air valve. The two sides of the shaft are connected to two symmetrical working chambers, each of which has a diaphragm. When the compressed air enters the pump, the compressed air will be pushed into one of the working chambers through the air distribution mechanism, which will drive the movement of the diaphragm and discharge the gas in the other working chamber. Once the end of the stroke is reached, the air distribution mechanism will automatically push the compressed air into the other working room and push the diaphragm to move the diaphragm in the opposite direction. At this time, the two diaphragms will start to reciprocate continuously.

The cylinder head part of the diaphragm pump mainly uses a diaphragm to separate the liquid to be transported and the working liquid. The diaphragm is usually made of materials with good flexibility and corrosion resistance, such as polytetrafluoroethylene. When the diaphragm moves to the transmission mechanism, the pump cylinder will work under negative pressure, which will suck the liquid into the pump. When the diaphragm moves to the other side, it will expel the liquid. Generally, the pneumatic diaphragm pump has good sealing performance, so the liquid will not easily leak during transportation. It is suitable for transporting highly corrosive and highly viscous liquids.

Why do we choose to use a diaphragm pump?

Diaphragm pump is one of the pumps that are suitable for use in various industries for processing and transporting various fluids. The diaphragm pump can be installed in various places, as long as it has compressed air, the diaphragm pump can use compressed air as a power to transport liquid. Therefore, the diaphragm pump does not need electricity to drive, and does not produce sparks, which is suitable for transporting some flammable and explosive medium. There are no rotating components inside the diaphragm pump, so it will not cause friction or damage to the medium. The maintenance cost of the diaphragm pump is relatively low, and there is no leakage issue during the operation.

Diaphragm pumps can be used to handle viscous liquids, such as mud. They can usually absorb liquid automatically and work efficiently. The size of the diaphragm of the diaphragm pump and its working chamber can determine the pressure that the pump can withstand and the speed of the flow rate. The media that the diaphragm pump can deliver are mainly the following:

1. Highly corrosive chemicals (strong acid, strong alkali)

2. Viscous liquids, such as sewage, mud, pottery glaze slurry, glue and adhesives

3. Volatile or flammable liquid

4. Emulsifiers, creams

5. Pigments and paints

6. Liquid foods, such as sauces, jams, etc.

7. Medical drugs

8. High temperature liquid

Precautions when using the diaphragm pump:

  1. Ensure that the particle size in the medium does not exceed the safety standards of the pump.

  2. When compressed air enters the pump, make sure that the pressure cannot be greater than the safety pressure range that the pump can withstand.

  3. When installing the pump, it is necessary to fix the pump to avoid impact and sparks during vibration.

  4. It is necessary to regularly check whether the pump system is safe and reliable.

  5. When using the pump, it is necessary to avoid placing the pump near a fire source or an explosive place. Try to place it in a well-ventilated environment.

Read through the article above, we can understand the basic information of diaphragm pump and how does it works in the industry sector. If you would like to know more about the diaphragm pump or purchase it and spare parts, please contact our MecHero at 011-7000 7687 or email We're looking forward to serve you better. MecHero is an online platform which provide various hardware products such as mild steel, stainless steel, carbon steel, pvc, piping accessories, bearing, etc.

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