Regarding how pneumatic diaphragm pumps regulate flow rate

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This post was last edited by Shanghai Nengyu Pumps and Valves on 2018-4-21 at 21:32. Pneumatic diaphragm pumps boast the advantages of simplicity and multiple ways to control flow rate. Flow control is generally achieved through two methods: 1. By regulating the pressure of the compressed air (air source) at the inlet; under constant other conditions, the air pressure is proportional to the flow rate at the outlet of the diaphragm pump. 2. The outlet flow rate can also be adjusted by regulating the opening degree of the valve at the outlet pipe of the diaphragm pump. In practical operation, adjusting the flow rate by controlling the pressure of the air supply is the preferred method; it is the simplest way to do this, and it also helps to extend the pump’s service life as well as reduce energy consumption A compressed air source is used; generally, the starting pressure for a pneumatic diaphragm pump is 0.2 MPa, with a maximum operating pressure of 0.7 MPa (this value should not be exceeded, as doing so may shorten the lifespan of the diaphragm under prolonged and intensive use). Within this pressure range, an air filter and pressure reducing valve can be installed after the air inlet but before it, so as to adjust the pressure of the air supply to an appropriate level. The higher the pressure, the faster the diaphragm moves inside the cylinder, resulting in a higher flow rate; conversely, as the pressure decreases, the diaphragm moves more slowly, and the flow rate also decreases. Moreover, since diaphragm pumps are not metering pumps, they cannot precisely control the flow rate; they cannot replace metering pumps and can only provide approximate control over the flow rate.