How Does An Electric Pump Work? | How to Select Electric Pump

A pump is an equipment that transfers a fluid (liquid or gas) or slurries through the mechanical action by converting electrical power into hydraulic power. The working of a pump depends on various energy sources such as wind power, manual operation, engines, or electricity. The pump size varies depending on the application, and the pump sizes range from small to large-scale industries. There are multiple types of pumps and electric water pump is one of them.

This is a short introduction to the pump. Now, let’s move to our main topic, “electric pump.”

What is an Electric Pump?

An electric water pump (EWP) is an electrically powered mechanical device. This pump drives through an electric motor. Power supplies from the transformer via the switchboard. After that, this power deliveres from the switchboard to the electric pump via a power cord that attaches to the water pipe.

Electric submersible pumps are also called ” submergible ” because they are mainly used in oil production for the manual lifting of oil.

electric pump

Mechanical pumps are used for various purposes, including ventilating and filtering ponds, filtering aquariums, pumping water from wells in the automotive industries for fuel injection and water cooling.

In the medical industry, pumps are utilized in the biochemical process of drug development and manufacture. They are used as artificial hearts and artificial replacements for parts of the human body, particularly penile prostheses and artificial hearts.

In the energy industries, electric pumps use for pumping natural gas and oil, for driving cooling towers, and other parts of air conditioning, ventilation, and heating systems.

How does an electric pump work?

An electric water pump requires electricity to run, and the transformer provides the necessary electricity through a switchboard. The motor of the electric pump converts electrical energy into mechanical energy.

In the case of electric pumps, the entire assembly immerses in the pumping liquid. Some of these pumps can be submerged or placed in a dry location, while others can be completely submerged.

The submersible pump used in the ESP device is a multistage centrifugal pump that works in a perpendicular position.

As the electric submersible pump shaft rotates, the impeller also rotates, and it forces the liquid to the bottom through the inlet of the pump or gas separator. Artificial lift data needs to determine the input-to-production ratio and productivity index that represent the potential productivity from the reservoir.

An artificial lift is a method that lifts hydrocarbons by the reservoir to the surface because the pressure in the reservoir is insufficient to force the oil to the surface. There are two types of artificial lifts: above-ground facilities and underground facilities.

The mechanism of operation of mixed flow and radial pumps is that the diffuser loses its kinetic energy when the generated liquid is subjected to the enormous centrifugal force caused by the high speed of the impeller. In the diffuser, the kinetic energy converts into pressure energy.

For better understanding working of ESP, watch the below-given video

Read More: Working of Electric Vacuum Pump

Features of Electrical Submersible Pump (ESP)

An electrical motor works at a comparatively constant speed, and the pump rotates through a shaft that connects to the parts of the guard. The device powers from below through cables attached to the pipeline, and liquid enters into the pump during operation.

As the liquid is generated, the pump becomes very efficient, and a large amount of free gas makes the pump ineffective. ESP can only handle 10% to 20% free gas or more than that; it can result in poor performance.

Some other features of ESP are given below:

  • This pump can produce high-temperature wells, gassy wells and high viscosity oil, e.tc.
  • The pump and the motor are suspended on the tubing at a certain depth in the well.
  • An electrical water pump is economical and effective in lifting large volumes of liquids from wells.
  • It has high cost than other methods.
  • If conditions are favourable, then ESP can run for several years.

Read Also: Working of Submersible Pump

Components of the Electrical Pump

 The electric pump has the following major components:

  1. Motor
  2. Casing
  3. Pump
  4. Protector
  5. Power Cables 
  6. Switchboard 
  7. Inlets 
  8. Transformer

Electric Submersible Pump components

1) Motor

The ESP has a two-pole three-phase squired cage induction motor that operates at 60Hz with a speed of 3500rpm. This motor is fill up with very high insulating mineral oil to ensure dielectric strength. It has excellent lubricity and thermal conductivity of bearings.

The motor frame can be one piece or multiple bolted-on tanned pieces to provide the required performance. The motor selects according to the maximum outside diameter that can be operated in a given frame size.

2) Pump

Main article: Pump and its types

An electric submersible pump is a multistage centrifugal pump. A well-designed electric centrifugal pump operates the pump in the optimal flow rate range. This flow rate adjusts according to the capacity of the reservoir.

The stage type used decides the design volume fraction of liquid production. The number of stages determines the total number of construction heads produced and the required motor power.

3) Protector

The protector is also known as an equalizer or sealed section. It fills with oil that high resistance. The main objective of the protector is to insulate the motor oil from the fluid in the wellbore while balancing the pressure at the bottom of the wellbore and the internal pressure.

The protector has specific functions. It has a thrust bearing that connects the pump to the motor by linking the casing to the drive shaft. It also uses for isolating the motor oil from the downhole fluid and absorbing the axial thrust from the pump shaft.

Read More: Different Types of Pumps

4) Power Cables

A special submersible cable uses to power the downhole motor. These power cables have two types: round cables and flat cables. An electric cable is one of the three conductors that act as a conductor to serve electricity from the switchboard to the motor.

The composition and thickness of the insulation layer determine the resistance of the conductor to leakage current.

5) Inlet

An electric pump has two types of inlets that are standard inlet and gas separator inlet. These inlets used to permit liquid to enter inside the pump. The intake reduces the quantity of gas entering into the gas pump separator. If the gas to liquid ratio is higher than the pump capacity, we use a gas separator inlet.

6) Transformer

An electric submersible pump has three transformer configurations: one three-phase autotransformer, one standard three-phase transformer, and three single-phase transformers. A transformer requires because the primary voltage drop does not match the requirements of the down-hole motor voltage.

7) Switchboard

A control panel or switchboard is a motor control device with a standard switchboard voltage range of 600V to 4900V. The control panel also knows as the control panel work surface.

The complexity of control panels ranges from simple motor starter/disconnector to very complex monitoring devices. It provides safety to prevent damage to the down-hole device. Solid-state switchboards protect underground equipment by detecting abnormal power services and turning them off.

Read Also: Different types of Submersible Pumps

8) Wellhead

The wellhead is a type of well-fitting suspension hose that use as a pressure-limited seal. It supplies a tight seal of pressure around power cords and pipes. It prevents gas from moving through the cord.

9) Pressure sensing instrument (PSI)

This part of the ESP provides sufficient downhole’s temperature and pressure data. The pressure-sensing instrument consists of two main parts: a PSI surface-hole unit and the other one is PSI down-hole unit.

10) Junction box

The junction box links the power cord from the switchboard to the well-type power cord. It can release gases that may leak from the well power cable into the atmosphere. This will prevent gas from building up in the switchboard.

What to look at while purchasing an electric pump?

When you start to purchase an electric pump, you will search for a pump that fulfils your requirements.  Some important factors to consider when start shopping for the best electric pump are:

  • Weight: If you frequently go to the office to commute or travel, a light pump is a good idea.
  • Sound: Few pumps generate less noise compared to others. If you want to use your pump in a community of people, you must choose a quieter pump.
  • Costs: Cost is the most important factor that should be considered during shopping for a pump. Therefore, you must choose a low-cost pump that also fulfils your requirements.

What are the advantages and disadvantages of an electrical pump?

AdvantagesDisadvantages
These pumps can use in water and oil wells.Its motor has severe overheating problems.
The electric pump has a low lifting cost.Well pumped off
These pumps can use for different confined areas such as urban and offshore areas etc.Stuck pump problems.
Can use in deviated well.This pump has a lack of cooling problems.
Almost possible to pump off the reservoirMaximum volume drops off fast with depth.
This pump has a high volume at a shallower depth.Tubing must be pulled to change the pump or cable.
Permanently mounted downhole pressure and temperature monitors. Control equipment required on each well
 Not easily adjustable for subsurface Systems
 This pump has a high repairing cost.
 Formation gas does not include aid inflow.

FAQ Section

Can we drive a car without an electric water pump?

If we drive a car without a water pump, our car’s engine can immediately overheat, resulting in an uncomfortable and expensive shutdown.

Does an electric water pump add horsepower?

In simple words, it doesn’t add. In contrast to a mechanical water pump, an electric water pump is battery-operated. This means that no tape feed is required.

How does an electric water pump work?

The pump impeller directs engine coolant through the engine block, absorbs heat during the intake stroke, and reaches the radiator. In the radiator, the coolant dissipates the heat and returns to the pump.

What are the benefits of an electric water pump?

In electric water pumps, manufacturers can (with greater accuracy) adjust the amount of coolant flowing through the engine within a certain temperature range. Therefore, it is highly effective and meets the specific cooling needs of the engine.

How is an electric water pump different from a mechanic water pump?

In contrast to mechanical water pumps, electric water pumps are battery-operated. This means that no tape feed is required.

Read More
  1. Centrifugal Pump working and types
  2. Submersible Pump Working 
  3. Different types of Pumps
  4. Working of Vacuum Pump

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