How to Install Mechanical Seal in an End Suction Centrifugal Pump

End Suction Centrifugal Pump

Centrifugal pumps have a rotating shaft that sticks out from the back of the pump casing through a seal chamber or stuffing box. The mechanical seal is needed to prevent fluid from leaking into the atmosphere along this shaft. Failure of these mechanical seals can have serious implications for the pump’s safety and reliability. It is therefore very important to install the seal properly.

How a Mechanical Seal Works in an End Suction Centrifugal Pump

A mechanical seal needs two smooth and flat seal faces in contact, one that is rotating with the shaft and another that is stationary with the casing. The faces are sealed to their holders using secondary seals. These are flexible so that they’re placed in contact and move to compensate for any misalignments or wear and tear. The faces however need lubrication to function at their best.

Steps for Installing a Mechanical Seal in Centrifugal Pumps

Here are 7 simple steps to follow when you are installing or replacing a mechanical seal in end suction centrifugal pumps:

1. Make sure the power is off

Make sure you cut the power so that the motor is not in motion. It’s even better to be doubly sure by cutting the main supply so that the motor may not start up while you’re working on it. 

2. Isolate the fluid from the pump

Next up, shut both inlet and outlet isolation valves and drain the pump casing by removing the drain plug.

3. Dismantle the pump

Use a wrench to unscrew the bolts holding the housing of the pump in place. Detach the pump carefully and keep the bolts safe for reassembly later.

4. Identify the stuffing box arrangement

If the pump is of the back pull-out design, remove the spacer element in the coupling, remove the casing bolts and pull the pump away from the casing. You can then access the seal without having to disconnect the casing from the piping. 

In case the pump is not a ‘back pull-out design, you’ll have to completely disconnect the pump after you disconnect the coupling between the pump and shaft. If the pump is a close-coupled design, you’ll have to remove the entire pump.

5. Remove the impeller

Dismantle the impeller of the pump. You can find the seal located on the shaft behind the impeller. Detach the shaft by holding it in place using a wrench and then rotate the impeller to unscrew it.

6. Detach the old seal

After removing the impeller, you can access both the rotary and stationary seal parts. The parts are usually held in place with screws all along the shaft. Remove the screw and pull away the rotary seal parts, and then remove the stationary part of the seal.

7. Replace the seal

Now place the replacement seal parts along the shaft. Push the stationary part into the casing using a new o-ring or gasket material. 
For any guidance on your centrifugal pumps, including all your sealing needs, feel free to speak to our experts at 022 43436655 or email us at We at VEMC are authorised Kirloskar dealer based in Mumbai and deal in a range of Kirloskar centrifugal pumps including multistage centrifugal pumps, (also called horizontal multistage pumps).

Centrifugal Pumps are Energy Guzzlers. How does Pump Energy Audit Help?

Centrifugal Pumps

A centrifugal pump can seriously raise your energy costs if you’re not keeping tabs on its efficiency levels. It is necessary that you take timely measures to eliminate inefficiencies or replace the pump altogether as the last resort. The most effective method in this regard is a thorough energy audit that can bring forth all the irregularities or issues with the pump’s performance. It can also give an estimate of energy savings if you switch to a different pump. In this blog, we talk about how an energy audit of your centrifugal pump can contribute to significant savings and cut down on costs.

Costs of Pumping

Pumping is a rather expensive affair across the world and more so in an energy-strapped developing country like India. According to some estimates, pumps consume 10% of power across the world, and switching to a more efficient water pump could save up to 4% of electricity globally. 

The main reasons behind the high costs of pumping could be an inappropriate selection of pumps, old inefficient design, improper layout, etc. By switching over to a more energy-efficient pump, you can reduce your bills, increase productivity, boost profits and enhance business competitiveness.

Centrifugal Pumps Consume a Lot of Power

Centrifugal pumps consume anywhere between 25% and 60% of a plant’s electrical motor energy. This can be made worse if the pump is improperly sized or poorly performing. Lack of maintenance and poor condition of the pumps is other reasons for the spike in running costs of a pump. This requires proper matching of a pump of the right capacity with the operation at hand. Likewise, a properly scheduled maintenance regime is a must to eliminate inefficiencies and overdrawing electricity over the lifespan of the pump.

Steps to Follow

An energy audit is the best way to keep the rising electricity costs in check. It is highly beneficial for business, society, and the environment at large. A pump energy audit is conducted by following these steps:

  1. Shortlist all the pumps for the audit
  2. Measure parameters like flow, pressure, and energy consumption
  3. Calculate the pumping efficiency
  4. Discuss the case with a specialist like an engineer or the maintenance staff
  5. Analyze data
  6. List recommendations and present them in the final report

How you can Save Energy

After an energy audit, you can get an in-depth understanding of the gaps, and the affirmative action that must be taken to fill them. With comprehensive data collection, analysis and modeling, it also gives you an idea about how much you can save by switching to a new alternative. In most industrial pumping systems, energy audits can help save up to half the energy costs!
VEMC can take care of the energy audit services of your pumps. We have all the expertise required to carry out Performance Measurement and energy optimisation of pumps and motors. Our team can provide a superior analysis of your current energy consumption and also the annual expenditure followed by a cost-returns-based proposal for different alternatives. For further information, feel free to call us at 022 43436655 or email us at

How are the centrifugal pumps important for various machines

The Kirloskar centrifugal pumps – and all other centrifugal pumps for that matter – are a kind of a dynamic axisymmetric turbomachine that work-absorbing. Industries use them to move fluids. In this case, they get help by changing the rotating kinetic energy to hydrodynamic energy that you need for the flow of the fluids. This rotational energy comes from an electric motor or an engine. The fluid, in this case, enters the impeller that is present close to the turning axis. Before this, it flows outward in a centrifugal motion. It flows into the volute chamber that is also referred to as diffuser. Industries use these pumps in areas such as water, petroleum, sewage, and petrochemical pumping. 

How do these pumps work?

As the centrifugal pumps distributors would tell you, these pumps work like most other pumps out there. This is in the sense that they also convert rotational energy, which is coming from the motors to the energy that you get in moving fluids. In this case, a part of the fluid goes into the kinetic energy that is contained in the fluids. This fluid enters via the eye of a particular casing. It normally gets caught up in the impeller blades.  After this, the fluid gets twirled in a vague and outward manner.   

Vertical centrifugal pumps 

You can always buy a centrifugal water pump in India from the top brands such as Kirloskar. The vertical centrifugal pumps happen to be known as cantilever pumps as well. They are built in such a way that they contain a shaft that is unique to them. They also have a bearing support configuration. It is this particular design that permits the volute to hang in on the sump even as the bearings are placed externally. This kind of pump does not use any stuffing box to seal the shaft. It can use throttle bushing though.

Froth pumps

A centrifugal pump in India can generate the froth and take care of the same as well. These pumps come in handy when it comes to separating rich minerals like bitumen from sand as well as clays. These pumps normally contain air that would block the traditional pumps. This can lead to significant loss of the prime as well. When these pumps are used in the paper and pulp industry the impeller are drilled with holes. In this case, the air goes out to the back of the impeller in question. 

Multistage centrifugal pumps

You also get Kirloskar centrifugal pumps that can be regarded as multistage centrifugal ones. The suppliers of these pumps design them in such a way that they have at least 2 impellers. These can be put over on the same shaft or they may be mounted on separate shafts as well. In the journey, in this case, the fluid is directed towards the center. In this case, it makes its way towards the discharge. This happens over the outer diameter. In the case of the outlets with higher pressure, the impellers can get connected in the series. In case of higher flow outputs, these impellers can get connected in parallel.