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Know Your Submersible Pump from Inside Out

Know Your Submersible Pump

A submersible pump uses inertial force to drive the water out of wells, tanks, lakes, ponds or other vessels. This mechanical equipment remains submerged and it is installed with various surface and down-hole components. In a submersible pump installation, there are a handful of different products that work together, playing an important role in the overall function of the submersible pump. Ever look at some parts and wonder “Where does this belong?” or “How do these parts work together?” In this post, we take a look at a variety of products for submersible pumps, what their roles are and how they work together.

Surface Components:

  • Transformers
  • Motor Controllers
  • Junction Box
  • Wellhead

Main Down-Hole Components:

  • Motor
  • Seal
  • Pump
  • Cable

Additional Down-Hole Components

  • Data Acquisition Instrumentation
  • Motor Lead Extension
  • Cable Bands And Protectors
  • Gas Separator
  • Check Valves
  • Drain Valves

Components of Submersible Pump:

1. Submersible Water Pump

A submersible pump drives the water out of the wells and towards the surface using centrifugal force. A hermetically sealed motor helps in this action. It remains connected to the body of the pump. A submersible pump functions by converting the rotary motion into kinetic energy. The impeller blades attached to the pump convert the kinetic energy into pressure energy.

The main purpose of this pump is to drive water out of various reservoirs whilst staying submerged into the water or other fluids. This pump is equally useful in hot water-heavy oil applications. In this scenario, a hydraulic motor is used in wells instead of an electric motor and hydraulic motors are powered by pressurized liquid which is driven out by the submersible pumps.

This pumping device needs no priming due to staying submerged in water or any type of liquid. It is an excellent choice for many applications since no cavitation builds up inside the pump.

Single-stage submersible pumps are suitable for industrial applications or for drainage/sewage purposes.

Multi-stage submersible pumps are ideal for industrial, municipal, commercial, or residential applications.

2. Check Valve

The check-valve or non-return valve prevents the backflow of fluid into the pump. The location and number of the check-valves depends upon the depth of submersible well-pump configuration. A pump that is installed at less than 200 feet depth will need one check-valve on the surface of the wellbore and one check-valve at the pump’s exit or discharge. However, the number of check-valves increases when a pump is installed at a depth of 200 feet or more. The following factors are considered before installing check-valves.

  • Volume and velocity of water
  • Submersible well pump’s weight
  • Piping and friction loss of the piping
  • Pressure drops of the check-valve

3. Easy Tie Adapters

The easy-tie adapters are threaded into the discharge on the check-valve of the submersible pump and enter the poly riser pipe. It is possible to thread another adapter into the pitless adapter at the well-head. This additional adapter is connected to the ‘poly riser’ pipe after being threaded. The safety rope/cable is securely fastened through the lug with a hole. This particular part can be used to secure the submersible pump to the ‘well head’ in the event of a pipe failure.

4. Clamps

The hose clamps seal the poly pipe to barbed insert fittings. This results in a watertight sealing and a secure connection that cannot be pulled off. The clamps are made of 300-series stainless-steel which is known for excellent corrosion resistance. This series of stainless-steel requires simple maintenance and the strength of the alloy remains intact even at higher temperatures. Therefore, the steel clamps will last through the life of the system.

5. Heat Shrink Splice Kits

The pump cables stay connected to the leads on the pump’s motor and the ‘heat-shrink’ splice kits are designed to secure this underwater electrical connection. The cables are cut in a staggered position which decreases the diameter of the outer cable and sets the electrical connection.

6. Safety Rope

A submersible pump will fall to the bottom of a well and will get lost if the pipes become separated. A safety rope prevents the pipes from separating. It remains directly attached to the pump and secured at the well-head. If the riser pipe fails to function, then safety ropes can be used to pull a submersible pump out of the well. This is an additional benefit of having a safety rope.

7. Torque Arrestor

Torque arrestors are installed on 1-inch and 1-1/4-inch riser pipes and benefit a pump in different ways.

  • They keep a submersible pump centered and prevent it from twisting inside the well casing.
  • They protect the pump cable.

8. Pump Cable

A two-wire or three-wire pump is used with a submersible pump and the cables supply electrical power to the pump.

  • In a two-wire pump, the starting capacitor is built into the submersible motor.
  • The three-wire pumps have no capacitor built into the motor. They need a control box which remains inside the pump house at the well-head of the submersible pump.

9. Pressure Switch

A pressure switch controls the operations of the submersible pump. The built-in membrane of this switch moves backward and forward to exchange the pressure of a water system. There are different models of pressure switches, such as standard, medium and heavy-duty. Different models of pressure switches are designed to control different levels of pressure and electrical ratings.

10. Pressure Gauges

The users can easily monitor the functional status of a submersible pump using pressure gauges alongside being able to view the ON/OFF settings of a pump’s operating switch. The pressure gauges remain in the accessory parts of a submersible pump.

11. Impellers

The impellers of a submersible pump are fitted with multiple fixed blades. These rotating parts convert the kinetic energy of water into pressure energy and drive the water out of its original location.

12. Inlet and Outlet Valves

The inlet valve of a submersible pump is used to draw the water into the pump and the outlet valve is used to release the water from the pump.

13. Drain Valves

The drain valves are also known as the boiler drain valves or sediment faucets. They are present at the second outward facing accessory port. These valves are used in order to –

  • Collect water samples
  • Collect water from the systems
  • Drain the tank and water system if the pressure tank needs replacement

14. Ball Valves

It is possible to stop the supply of water to the pump-house using ball valves if any of the pump’s components fail to operate properly. These valves are installed at the exit (discharge side) of the pressure tank. They isolate the water-well pressure system from the plumbing system.

15. Sediment Filters

The efficiency and longevity of the water-treatment equipment decreases if there are sediments in the equipment. The sediment filters prevent any sediment from getting into the water-treatment equipment.


A submersible pump has to be installed along with multiple components and it is evident that each component plays an equally important role in ensuring the flawless function of a submersible pump. You may use this list to install a submersible pump along with all essential parts. Was this article helpful to you? Find more informative articles at Unnati Pumps.