Diaphragm metering pumps are a type of pump that pumps liquid (such as water, chemicals, gas, etc) in a particular motion and therefore flow. The rate of flow can be changed at any time and as the name suggests, diaphragm metering pumps work by compression and decompression; so the liquid can only pass through the pump during specified motions. In this type of pump, the natural flow of fluid is maintained and the fluid will not go back in the opposite direction.

Diaphragm Metering Pumps – Where Are They Commonly Found

These pumps are designed to be used in the following areas:

  • Water treatment plants
  • Chemical processing plants – the handling of corrosive fluids
  • Swimming pools
  • Farming and agricultural industry – the handling of slurry
  • Food processing and manufacture
  • Brewing and distilleries

The main benefit of working with high pressure pumps is that there is very low possibility of product leakage and in the case of poisonous or hazardous liquids or chemicals, this is imperative.

How do diaphragm metering pumps work? Diaphragm metering pumps can be operated on fluid power (hydraulics) or mechanically. The diaphragm itself is made of a durable and heavy duty material which also prevents liquid from seeping through the seal. Some diaphragm metering pumps come with an auto-detection failure system which proves to be very beneficial in keeping the metered fluid contaminant-free.

Types Of Hydraulic Operated Diaphragm Metering Pumps

There are three main types of hydraulic operated diaphragm metering pumps:

  • Single
  • Double
  • Sandwich

Single diaphragm metering pumps has a partition so that the hydraulic chamber is carefully sealed away from the fluid that is being discharged.

Double diaphragm metering pumps has two diaphragms just as you might expect from its name. If a highly corrosive fluid damages one diaphragm, the backup diaphragm will take over the job of the damaged one which provides enough time to replace the worn out diaphragm. This ensures that the dangerous liquid does not leak out. This type of pump is generally made to handle double the flow than that of the single. The way in which they are designed means that there is no contact whatsoever between the power source and fluid being pumped.

Finally, sandwich diaphragm metering pumps are essentially two of the same pumps fitted together to work as one. The beauty of this type of metering pumps is that should one of them fail unexpectedly, the other one can act as a backup and they are monitored internally by a pressure gauge. Next we will take a look at electronic metering pumps.