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 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. There are multiple types of pumps and the electric water pump is one of them. This article mainly explains the electric pump working, types and applications.

What is an Electric Pump?

An electric pump is a device that uses electricity to move fluids, such as chemicals, oil, or water. This pump is driven by an electric motor. The electric motor gets power from the transformer via the switchboard. 

electric pump

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

In the medical industry, electric 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 are used for pumping natural gas and oil, for driving cooling towers, and other parts of air conditioning, ventilation, and heating systems.

Electric Pump Working

An electric water pump requires electricity to run. It is connected to a transformer that 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 shaft of the electric submersible pump 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.

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, etc.
  • 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

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.

Read More: Different Types of Pumps

3) Protector

The protector is also known as an equalizer or sealed section. It fills with oil that has 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.

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 are used to permit liquid to enter the pump. The intake reduces the quantity of gas entering 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 starters/disconnectors 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

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.  Consider the below-given tips to buy an electric pump:

  • 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.

Advantages and Disadvantages of 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.

Applications of Electric Pumps

Electric pumps are used for multiple applications. The electric pumps are most commonly used for:

  • Chemical dosing: They utilize to add an accurate amount of chemicals, such as disinfectants, alkalis, or acids, to water treatment systems or other industrial processes or homes.
  • Water supply: Electric pumps are used to supply water from reservoirs, canals, or wells to offices, farms, or homes.
  • Fuel transfer: Electric pumps are used to deliver different fuels, such as diesel or gasoline, from the fuel tank to aircraft, boats, or vehicles. These pumps are commonly found in airports, marinas, and gas stations.
  • HVAC System: They are used in HVAC systems to circulate refrigerant or water through cooling or heating coils.
  • Irrigation: These types of pumps are usually employed to deliver water to lawns or crops for irrigation. You may also use them to pump water from wells, lakes, or rivers and supply it by using drip irrigation systems, sprinklers, or other methods.

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  and Types
  3. Different types of Pumps
  4. Working of Vacuum Pump
  5. Reciprocating Pump Working and Types

Leave a Comment