The Fundamentals of End Suction Centrifugal Pump Explained

End Suction Pump Meaning

Each type of pump has its own strengths and weaknesses. As a buyer, you will often find it difficult to choose among the multiple pump types that can be selected for the same application. In this blog, almost all of your questions regarding end suction pumps will be answered.

An end suction pump is the most basic type of centrifugal pump typically designed with a casing. The suction is present on one end and the discharge is placed at the top. Hence, the name end-suction pump is given.

End Suction Pump Working

End suction centrifugal pumps normally contain an impeller and a casing which has coil windings. When the pumped liquid passes through the blades and fins of the impeller, its velocity increases. This liquid then passes through the volute casing. Here its high velocity is converted to into high pressure through a process of diffusion.

End suction pumps can be driven by any of these:

  1. A.C. electric motor
  2. D.C. motor
  3. hydraulic motors
  4. air motors
  5. petrol and diesel engines
  6. steam turbines

End suction pumps may be close-coupled or frame-mounted. These pumps are the best choice for intermittent and non-critical service applications.

End Suction Pumps Types - Close Coupled & Frame Mounted

As discussed earlier, end suction centrifugal pumps are basically of two types:

End suction Frame Mounted
Pumps – DN Series
End suction Close Coupled
Pumps – DNJ Series
End suction Frame Mounted Pumps – DN Series End suction Close Coupled Pumps – DNJ Series
End Suction Pumps – RCP Series Stainless Stamped End suction
Pumps – RST series
End Suction Pumps – RCP Series Stainless Stamped End suction Pumps – RST series

1) Frame Mounted End Suction Pump:

The frame mounted end suction pump has shaft and bearings that are independent of the motor. In order to transfer energy from the motor to the pump, a coupling between them is required. The frame-mounted category of end suction pump comes with a double volute design. The main features of this design are increased efficiency and lower life cycle costs. The footed bearing frame provides ease of maintenance while the footless volute permits discharge orientation flexibility. The impellers are trimmed and balanced offering customization as per the requirements, reduced noise, vibration and harshness and prolonged seal and bearing life.

2) Close Coupled End Suction Pump:

These are end suction centrifugal pumps in which the pump shaft and motor shaft are the same. Also, the pump bearings and motor bearings are the same. In this type, the impeller is directly attached to the one end of the motor shaft. Close coupled pumps require less space. They are also cheaper than frame-mounted pumps. Close coupled design provides space savings and compact construction. A permanent rigid alignment in these pumps is done to eliminate the need for all other alignments. This in turn, prolongs seal and bearing life.


There is a wide range of applications of the end suction pumps. They can be used in almost every industry dealing with transfer of liquids. Some of the areas include:

  1. Air Conditioning
  2. Heating and Ventilating
  3. Refrigeration
  4. Fire Protection and fighting
  5. Water transport and supply
  6. Cooling towers
  7. Plumbing
  8. Food and Drink Manufacture
  9. Circulating
  10. Industrial Water Pressure Boosting
  11. Industrial liquid transfer
  12. Water Treatment plants
  13. Irrigation
  14. Drainage
  15. Sprinkler systems
  16. Factory Pumping
  17. Chemical Process Industry
  18. Petroleum Products
  19. General Industry

About HI & NEMA and its standards

The Hydraulic Institute (HI) decides the product standards for the North American pumping industry. It also defines how the pump products should be, how their installation must be done, how they must be operated, their performance standards, testing of the equipment, the life of the machinery and their quality.

Also, the National Electrical Manufacturers Association (NEMA) actively defines product, process, or procedure with reference to their composition, dimension, construction, characteristics safety, and ratings.

These standards are widely utilized not only throughout North America but also worldwide. These two organizations implement sound technical standards that benefit the end user, as well as the manufacturer. They help you:

  1. Improve safety
  2. Improve the durability of the pumps
  3. Bring about economies in the product
  4. Enhance their performance by improving their efficiency
  5. Eliminate all the misunderstandings between the manufacturer and the buyer
  6. Assure quality levels
  7. Assist the buyer in selecting the proper product for his specific requirement

Opting for Rotech end suction centrifugal pumps has its own benefits:

  1. You can have great energy savings through their improved hydraulic design. Rotech Pumps are compliant with HI and NEMA standards. This creates a better efficiency in each individual pump which provides fabulous performance and minimizes the overall average power consumption.
  2. Rotech provides reliable end suction pumps that have a robust design. Longer pump life can be ensured by their extra features like sturdy bearing assembly and secure impeller fastening.
  3. Providing excellent customer service is their cornerstone for success. Rotech believes that a smart pump design will reduce the cost of maintenance. It provides modular construction and features.

Final Words

With a multitude of centrifugal pump configurations available in the market, it is extremely important for you as a consumer to fully evaluate the strengths and weaknesses of each type of end suction pump when buying a new pump for your industry so as to minimize the maintenance costs, especially when you are dealing with critical applications.

If you would like to learn more about suction pumps and their types, you may log on to the website