Gear Pump Types and Its Working

The gear pumps essential as well as most frequently used pumps. As the name suggests, these pumps are inbuilt with gears. The main function of these gears is to provide force energy to the water within the pumps. In simple terms, the function of this pump is to transfer the water from one location to another location with the help of gear instrument. If the system’s force remains similar then they’ll supply you the fixed flow speed. This article discusses an overview of Gear-Pumps. So let us discuss an overview of these pumps with types, working, advantages, disadvantages and their applications.


What is a Gear Pump?

The gear pump definition is, it is a PD (positive displacement) rotating pump which assists you to move water otherwise fluid with the help of inbuilt gears. This type of pump includes two or more gears that create vacuum force to drive the liquid within the pump. This pump can be built with different parts like shaft, rotors, and casing.

Gear Pump
Gear Pump

These pumps have high-pressure and are available in tiny sizes to supply constant liquid flow & a pulseless as contrasted to other types of pumps such as diaphragm & peristaltic pumps. The main benefits of using these pumps are superior like it can drive high thickness fluids, easy to use, operate and also maintain.

How does it Work?

The gear pump working principle is, it uses the gears actions otherwise rotating actions to move liquids. The rotating part extends the seal of liquid by the pump case to create suction at the inlet of the pump. Liquid drawn into the pump can be included in the rotating gears cavities and moved to the expulsion.

Types of Gear Pumps

These pumps are classified into different types but some of the basic gear pump designs are classified into two types which include the following.

  • External Gear Pump
  • Internal Gear Pump

1). External Gear Pump

An external gear-pump can be built with two gears namely interlocking and identical where interlocking gear is held up with separate shafts. In general, single gear can be driven with the help of a motor to drive the other gear. In a few cases, shafts can be driven by electrical motors, and these are held with bearings on every casing side.

When the gears appear from the mesh on the pump’s inlet side, they make an extended quantity. Fluid supplies into the cavities as well as trapped with the teeth of gear because the gears continue for rotating next to the casing of the pump. The trapped liquid can be moved from the inlet side to the discharge side in the region of the casing.

When the gears teeth become linked on the discharge surface of the gear-pump, then the amount can be decreased & the liquid is forced out beneath force. No liquid can be moved back throughout the center, among the gears, since they are linked. Close tolerances among the gears as well as the covering let the pump to expand suction on the inlet & stop liquid from leaking reverse from the expulsion side. The designs of these pumps can use helical, spur, otherwise herringbone gears.

Features of External Gear Pump

The features of this pump include the following

  • These pumps are solid in size with a simple design
  • These are sufficient to distribute high capacities because of their huge outlets.
  • It manages the pressures like low, medium otherwise high
  • The shaft support as well as close tolerance on both surfaces of gears.

2). Internal Gear Pump

An internal gear pump works on a similar principle except the two linking gears sizes are different with one revolving within the other. The rotor is a larger gear and also an inner gear, and it has the teeth projecting inside. A minor external gear is mounted, and this is mainly designed for linking by the rotor so that the teeth of the gear connected at a single end. A bushing and pinion can be connected to the pump case that holds the idler within the location.

A permanent semi-circular formed divider otherwise spacer seals the void shaped through the off-center mounting location of the idler & performs like a seal among the ports like inlet & outlet. When the gears appear from the mesh on the pump’s inlet side, they make an extended quantity. Fluid supplies into the cavities as well as trapped with the teeth of gear because the gears continue for rotating next to the casing of the pump. The trapped liquid can be moved from the inlet side to the discharge side in the region of the casing.

When the gears teeth become linked on the discharge surface of the pump, then the amount can be decreased & the liquid is forced out beneath force. Inner gear pump plans only utilize spur gears.

Features of Internal Gear Pumps

The features of internal gear pumps include the following

  • It can be run for a small phase.
  • It has a huge and big footprint.
  • The net positive suction head (NPSH) requirement is very low.

Advantages and Disadvantages of Gear Pumps

The advantages of these pumps include the following.

  • Maintenance is simple
  • It handles an extensive range of viscosities
  • Output is controllable
  • Easy to reconstruct
  • Cavitations are less sensitive

The disadvantages of these pumps include the following.

  • The liquid should be free of abrasives
  • Interlocking gears can also be loud

Applications of Gear Pumps

The gear pumps applications include the following.

  • These pumps are usually used for driving high thickness fluids like oil, resins, paints, otherwise foodstuffs.
  • These pumps are chosen where a high force o/p is necessary. These pipes are preferred in any condition wherever the supply is unequal. Because the pump output is not really influenced by force.
  • Both the internal and external pumps are commonly used in different fuel, lube oils, solvents and alcohols
  • The external pumps are used in chemical preservative, polymer metering, mixing and blending of chemical, agriculture, industrial, and mobile hydraulic applications.

Thus, this is all about the gear pump,  this pump can be used to move a liquid with frequently surrounded a permanent volume in linking cogs otherwise gears, moving it automatically to push a flat pulse-free flow relative to the rotating velocity of its gears. Here, is a question for you, what are the main features of a gear pump?