Introduction
A pump is a device used to move gases, liquids or slurries. A
pump moves liquids or gases from lower pressure to higher pressure. Technically, a pump is a unit used for
transportation of liquids, fluids and gases through pipes or similar channels.
The functionality of pumps is very simple; it consists of a suction mechanism
at one end where the material is drawn in. Counter pressure is developed at the
other end which forces the material out.
Pumps Classifications
Pumps
are classified as mentioned in below diagram
Positive Displacement Pump
Positive
Displacement Pump is one in which a definite volume of liquid is delivered for
each cycle of pump operation. Positive Displacement Pump differs from
Centrifugal Pump, which deliver a continuous flow for any given pumps speed and
discharge resistance.
 Positive Displacement ClassificationÂ
Reciprocating Pumps
In
a reciprocating pump, a volume of liquid is drawn into the cylinder through the
suction valve on the intake stroke and is discharged under positive pressure
through the outlet valves on the discharge stroke.
Piston Type
Piston pumps use a cylindrical mechanism to create a reciprocating motion along an axis, which then builds pressure in a cylinder to force gas or fluid through the pump. Piston pumps are used in lower pressure applications.
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        Piston Pump
Plunger Type
Plunger
Pumps are very similar to Piston Type and can be either vertical or horizontal
acting. The different between Plunger pump and Piston pump that the Plunger
pumps do not have piston rings, but are sealed only where the plunger
penetrates the casing
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   Plunger Pump
Diaphragm Type
A diaphragm pump is a positive displacement pump that uses a combination of the reciprocating action of a rubber or Teflon diaphragm and suitable non-return check valves to pump a fluid.
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         Diaphragm Pump
Rotary Pumps
Positive
displacement rotary pumps are pumps that move fluid using
the principles of rotation. The vacuum created by the rotation of the pump
captures and draws in the liquid.
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Gear Type
A
Gear pump uses the meshing of gears to pump fluid by displacement &
commonly used for hydraulic fluid power applications. Gear pumps are fixed
displacement, meaning they pump a constant amount of fluid for each revolution
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      External gear pump
Screw Type
Screw
pump is one of the oldest types of pump. It is a kind of rotary, positive
displacement pump that has one or more screws to transfer high or low viscosity
fluids along an axis.
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      Screw Pump
Lobe Type
Lobe
pumps are positive displacement pumps that use rotating lobes to direct flow.
Lobe pumps are similar to gear pumps in operation in that fluid flows around
the interior of the casing.
  Lobe Pump
Kinetic pumps
Kinetic Pumps transform fluid kinetic energy into fluid static pressure energy. Centrifugal Pumps are good example of this type of pump.Centrifugal Pump
A
centrifugal pump is a rot dynamic pump that uses a rotating impeller to increase the velocity of a fluid.
The fluid enters the pump impeller along the rotating axis and is accelerated
by the impeller, flowing radially outward into a volute chamber, from where it exits into the
downstream piping system.Â
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      Centrifugal
pump
Axial Flow Centrifugal Pump
Mixed Flow Type
These
pumps borrow characteristics from both radial flow and axial flow pumps
 Mixed Flow Centrifugal Pump
Jet Pumps
A
jet pump is a combination of a volute centrifugal pump and a nozzle-venture
arrangement. The driving force lifting the water in this type of pump is
provided by a high pressure nozzle which creates a low pressure region in a
mixing chamber. This low pressure causes water to flow into the pump.
 jet pump
Air-Lift Pumps
Air-lift
pumps operate on the principle that a mixture of air and water will rise in a
pipe surrounded by water. An air-lift pump basically consists of a vertical
pipe partially submerged in water and an air supply tube allowing compressed
air to be fed into the pipe at a considerable distance below the static water
surface. The mixture of water and air is lighter than the water outside the
pipe and it rises in the pipe.
    Air-lift pumps
Hydraulic Ram Pumps
A
hydraulic ram pump is a motor less low flow rate pump. It uses the energy of
flowing water to operate. It is suitable for use where a large flow rate is not
required. The flow rate of typical commercially available units is limited to
approximately 14 gallons per minute.
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          Hydraulic ram pump
Regenerative Turbine Pumps
There
are two types as mentioned below
Overhung Impeller Type
Overhung Impellers are mounted on the extreme end of the shaft in a cantilevered condition hanging from the support bearings.
Impeller between Bearings Type
The
impeller (or impellers) is mounted on a shaft with bearings at both ends. These
pumps are further separated as single stage and multistage configurations.
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