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  • Sewage Pumps
  • Zuwa Pumps



Ernest Electro Engineering understands how the right decision can make a massive positive difference to your operations, while the wrong ones can be setbacks you would rather avoid.

To help you make an informed decision when working with us, we offer answers to some of our most Frequently Asked Questions (FAQs) about our pumps and their related topics. Can’t find the answer you were looking for in this FAQ? Be sure to get in contact with one of our representatives for details…

What is Pumps Efficiency?

This refers to how well it can convert one form of energy to another.

If there is one unit of energy supplied to the machine, and its output in the same unit of measurement is one half unit, the efficiency of it is 50%.

How Does Specific Speed Affect the Pump Curve?

Most pump designers see specific speed as the most important contributor to centrifugal pump design, It allows existing designs to be used, and yields test data that can be used to design similar higher and lower flow pumps as the specific speed of a pump is independent of the size.

How Does Pump Curve Shape Affect Efficiency?

Typical performance curves are flat at low values of specific speed, which becomes steeper on the curve as force increases. Efficiency is reduced at flow force levels, while it increases with them. The curve will reach its maximum in the mid-to-high 2000Nrange, and will begin decreasing above 3000N

What is a submersible pump?

The primary distinction between a submersible pump and any other type is that a submersible pump is completely submerged in the liquid it must pump. As a result, these pumps can be used in a wide range of pumping applications.

How does a submersible water pump work?

Submersible pumps are submerged in water. Their motors are typically airtightly sealed and coupled to the pump’s body. Submersible pumps push water to the surface when rotary energy is first converted into kinetic energy and then pressure energy. Water pressure forces water into the pump, where it is moved to the surface by pressure energy.

What kinds of submersible pumps are there?

Depending on your water needs, there are several types of submersible pumps to choose from: bladder and ballast pumps, borehole pumps, booster pumps, centrifugal pumps, condensate pumps, dewatering pumps, fountain pumps, grinder pumps, macerator pumps, micropumps, sampling pumps, trash pumps, utility pumps, well pumps, etc.

Are submersible pumps safe?

Because the electric cables connected to the motor of the submersible pump are sealed, they can be used safely in fluid medium or water. In addition, the pump and motor are mechanically connected and cannot be easily separated. As a result, finding and installing a matching pump size is simple and safe if you have accurately measured the borehole diameter.

How do I choose a submersible pump?

Examine future needs before purchasing a submersible pump. For example, consider whether the pump will be used in a pond or for a watering hole that will feed a herd of dairy cows on your property. Perhaps you require a heavy-duty pump to function effectively in the wastewater industry. Because the pump’s durability is determined by its run time, installing a large pump is a waste of money. Understand how the motor works to evaluate its effectiveness. Under their load limit, premium quality pumps operate efficiently. The full load amperage (FLA) rating is the most accurate way to determine how much workload the motor shaft can handle. The impeller attached to the submersible pump must also be considered. Another thing to consider is the pump head. It is the amount of pressure that a submersible pump can generate. It is calculated from the water/liquid surface that must be pumped.

What is a submersible dewatering pump?

A submersible dewatering pump is used to remove water/fluid from wastewater tanks, rainwater pits, mining pits, and other similar locations. The impeller vanes of these pumps allow suspended solid particles to pass through, and the vane design determines the particle sizes the pump can handle. These pumps typically have an open or semi-open impeller and a sealed electric motor that serves as the prime mover.

What are submersible pumps used for?

Submersible pumps can be used for borehole or open-well applications in clear water applications. In addition, submersible pumps are commonly used for water circulation and irrigation systems in residential apartments, commercial complexes, and municipal and industrial water circulation and irrigation systems. Submersible dewatering and cutter pumps are used for sewage treatment plants, water wells and deep well drilling, and mine dewatering.

Some submersible pump applications include:

· Boreholes

· Drainage

· Firefighting

· General industrial pumping

· Mine dewatering and irrigation systems

· Seawater handling

· Sewage pumping

· Sewage treatment plants

· Slurry pumping

· Water well and deep well drilling

What are the advantages of a submersible pump?

· Simple to set up. Unlike surface pump sets, a submersible pump installation does not require a foundation.

· Priming is unnecessary because the pump is always submerged, and water is present inside the pump due to the pressure gradient.

· The operation is completely silent. The submersible pump produces less noise than a surface pump. These pumps also have the benefit of being underground.

Do submersible pumps have check valves?

Submersible pumps have check valves that allow water to flow in only one direction. Some submersible pumps include built-in check valves and can be used without an external check valve if the pump setting is not too deep.

Can submersible pumps operate horizontally?

Yes, single-stage open-well submersible pumps are horizontally installed. However, borehole submersible pumps are installed vertically.

Can a submersible pump run continuously?

Yes, this pump is designed to operate while completely submerged in water and will turn off when the water level reaches six millimetres.

Is it possible for a submersible well pump to overheat?

This occurs when the pump does not have consistent water flow. The issue is that if there isn’t enough water, there won’t be enough fluid to keep the motor cool. In situations like this, your pump will overheat and break down.

Why do submersible pumps break down?

The five most common causes of submersible pump failure are temperature and overheating, hydraulic loading, motor seals, voltage supply, and voltage spikes.

What causes my submersible pump to overheat?

If the pump loses prime, the water inside the pump casing can become extremely hot due to impeller friction and eventually turn to steam. A small air leak in the suction line or a leaking shaft seal are the most likely causes of a pump losing prime.

Is it possible for a submersible well pump to run dry?

Submersible pump motors rely on the flow of water past the motor for cooling, and if the pump is left on when the well runs dry, it will overheat, melt the insulation on the windings, and eventually stop working.

How far can a submersible pump be submerged?

A deep-well submersible pump draws water through a single pipe that connects the inside well to the house using a pressure tank. Although a submersible pump can extract water from depths of up to 120 m, it must be removed from the well casing for repairs.

Can a submersible sump pump operate indefinitely?

A sump pump can run continuously and cycle flood water for up to 22 hours if you have a good quality sump pump, the proper environmental settings, and keep it well maintained. Sump pumps can work nonstop for nearly a day before faltering, slowing down, or burning out.

Can you leave a submersible pump underwater?

A submersible water pump performs the same function as a standard water pump in that it drains water. It does, however, have the added benefit of being placed even underwater and still functioning properly. Some pumps function only when completely submerged underwater, while others function even when placed on a dry surface.

How long can a submersible pump be submerged?

Submersible pumps operate underwater and have a longer lifespan. The water surrounding these pumps keeps them cool, reducing wear and tear. A submersible pump will last about 15 years if the water contains little sediment, but it will only last about six years if it includes a lot of sediment.

Does a submersible pump need priming?

Submersible pumps have a submerged suction intake, which eliminates the need for priming. These pumps are typically used as a backup when priming a standard end-suction centrifugal pump would be difficult. When using a submersible well pump, make sure to use a flow induction sleeve to keep it from overheating.

Priming is not required if your pump is submerged, such as a submersible or vertical pump. Furthermore, when the pump is at a lower elevation than the supply, there is no need to prime it. This is because the low elevation ensures that the pump suction is completely filled with liquid at all times, a condition known as flooded suction.

Well pumps must be primed to reduce the risk of pump damage during start-up. Priming prevents the pump impeller from becoming gas-bound and unable to pump the required liquid. If you want consistent operation, ensure the pumps are primed so that air or gases are expelled from the suction and replaced with liquid. Keep in mind that the pump will not function properly if it is not filled with liquid. Furthermore, failing to prime the pump will result in an overheated pump system and can cause damage to the pump’s internal components.

A self-priming pump eliminates the need for priming. This means that the pump can expel air and gases from itself. You also don’t need to prime a pump if it’s in a location where it’ll always be full of liquid.

If you do not prime the pump and provide the necessary fluid, it will run dry and may cause damage to the pump’s components. Furthermore, failing to prime a pump or priming it incorrectly can result in a malfunction. Pump repair is not only costly, but it can also be inconvenient because you must wait for the pump to be repaired before you can use it again.

What happens if the water pump runs dry?

Running a standard centrifugal pump with a mechanical seal dry will generally result in the mechanical seal being damaged. Other centrifugal pumps, such as mag drive pumps, can overheat quickly and, because they are made of plastic, can frequently melt the internals of the pumps.

Pump dry run protectors are available to stop the pump before any damage occurs.

Positive displacement pumps like a peristaltic hose pump or an air-operated diaphragm pump are not damaged when they run dry.

Pumps with rubber on metal inside, like helical rotor pumps, will melt quickly and cause significant damage.

Contact Ernest Electro for Details

If you would like answers to further questions or would like to know more about our offers, be sure to get in contact with a representative from Ernest Electro today.

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