Questions About Pumps

What is efficiency?

When we talk about the efficiency of most types of machines, we are usually referring 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 units of measure, is one half unit, the efficiency of it is 50%.

 

What exactly is specific speed and how does it affect the pump curve?

Specific speed was first applied to centrifugal pumps on the 1800’s and was then a modified version of one developed for water turbines. You will find that most pump designers tend to see specific speed as the most important contributor to centrifugal pump design, allowing the use of existing design and the test data in order to design similar higher and lower flow pumps as the specific speed of a pump is independent of the size.

 

What are the individual efficiencies that affect operation?

• Volumetric efficiency
• Hydraulic efficiency
• Combined efficiency
• Mechanical efficiency

 

How is efficiency preserved?

One of the most important parts of the volute is the cutwater, or tongue. The cutwaters purpose is to maintain the flow into the throat while still minimizing recirculation back into the case. The optimum clearance between the cutwater and the impeller periphery is the smallest distance that doesn’t give rise to pressure pulsations during the vane tip passing. A properly designed pump will generally have a full sized impeller which meets these clearance criteria. When your impeller is getting trimmed, the distance increases and then allows more fluid to recirculate back into the case. As the recirculation increases, the hydraulic efficiency will decrease.

 

How does the curve shape affect the efficiency?

The typical performance curve is basically flat at low values of specific speed and it will become steeper as the Ns increases. The pump efficiency is lowest at low values of Ns and it will increase as the Ns increases. It reaches its max in the mid-to-high 2000 range and it will also begin to decrease above 3000.

 

Contact Ernest Electro on 011 792 9550/1/2 or visit our website on www.ernestee.co.za for more information about submersible pumps, sewage pumps and more.

The Role Of De-Watering In Mining

De-watering is a very important part of mining and it has a very important role when it comes to keeping the open pit and underground sites clean, dry and safe. In certain mining projects the de-watering is more important than it is for other projects. This is due to the location of the mine and the mine itself. If a mining project is not prepared for any water problems, they could face very large, and very costly setbacks to their operations. This is all preventable with a little bit of planning and proper management.

What Is De-Watering?

De-watering is the process of essentially keeping the mine dry, but with complex twists. This is because each site and mine is different, there are different means and methods to keeping things safe and dry. A mining site would focus on either or both objectives of: general mine dewatering (this process pumps the water away from the mine and its structures) and pore water pressure reduction (this process of strengthening the structure by controlling the pressure of the water while keeping it out of the mine.)

The Benefits of Mine De-Watering

A de-watering plan for the mine needs to be planned out and in detail long before any operations begin in order to ensure that everything is well understood. It is important to note that the most appropriate objective is being acknowledged and treated in order to ensure the true safety of the mine and miners. It is great for reducing the costs of blasting onsite. It reduces the cost of haulage as dry ore and waste rock weigh less than wet material. It improves the general condition of the working environment for the miners.

Ernest Electro Engineering

If you are in need of de-watering equipment, be sure to contact Ernest Electro Engineering. They supply professional and reliable mining de-watering equipment that allows you to keep your site dry and secure.

Why You Need A Water Softener

 

It may seem like a strange concept to some that you get hard and soft water, however this is a very common occurrence. The difference between the two is that hard water is water that contains a higher quantity of dissolved minerals, while soft water is treated water that with the only ion present being sodium, and rain water is naturally soft water. Hard water is the preferred drinking water because it contains more minerals than soft water. But we still do process our water in order to have soft water. The reason is that soft water is better for our chores and our homes.

The Problem With Hard Water

The problem with hard water lies within its reaction to our everyday household detergents, soaps and cleaners. The combination of hard water and certain chemicals or elements of the detergents create drain curd and other plumbing problems. Hard water has a negative reaction with our clothes and the washing detergents that we use, that leaves them grey and faded. It leaves a scale build up on your appliances, and it leaves stains on your sinks and bathtubs throughout the house.

Other Negative Effects of Hard Water

Hard water causes dry skin and hair, which is not always 100% preventable by shampoos, moisturisers and soaps. It blocks up our pores because it might not dissolve all the soap on our skin and that leads to blackheads. Hard water leaves your glassware brittle after a few washes, which makes it more sceptical to breakage. Hard water will increase your water bill in the long run because your plumbing will eventually need to work harder to deliver the water.

The Benefits of a Water Softener

A water softener is a highly beneficial thing to have if your home has hard water. The benefits will leave you feeling more refreshed physically, and all the things around you will have a longer lifespan and have a cleaner finished look. It will allow you to save money on your water bill, and on plumbing costs. You will be able to get more wear out of your clothes and you will not find yourself constantly buying new glasses. A water softener is an investment into your home, your wallet and yourself.

Ernest Electro

If you are in need of a water softener, be sure to get the best quality water softener, be sure to contact Ernest Electro Engineering.

What Is a Multi Crusher and Where Would I Use One?

A multicrusher is essentially a chopping unit. They are used to process liquids that contain solids in them, so that they can be rendered into a consistent medium. Utilising heavy-duty blades installed in a pumping system, inconsistent liquids can be run through these devices to render them into a usable form. There are a number of applications that are well suited to their use. Let’s explore a few of them here.

Multicrushers and Environmental Processes

There are a number of everyday, environmental processes that require a multicrusher to be completed. Processing sewerage is one such application that is essential for both municipal and industrial settings. Further industrial applications related to environmental processes include feeding dewatering devices, and processing mixed waste of water and oil.

Multicrushers and The Chemical Industry

The chemical industry sees a regular need to process liquids in various forms such as acids, solvents, fats, oils and pastes. Latex products often need multicrushers for processing, such as paints and coatings.

Multicrushers and Construction

Many of the crucial materials used for construction, such as concrete, are processed using multicrushers. In addition to concrete, these appliances also process mineral sludge, drilling mud, plaster masses, coating and more.

Multicrushers and Manufacturing

From ceramics to food, many manufacturing processes benefit greatly from utilising a multicrusher. Where manufacturing is concerned, these devices are used to process clay, lime, ceramic, and glazing. Where food is processed, everything from meat, fish, fruit, veg, starches and sugars (such as molasses) can be rendered using these wholly versatile devices.

Contact Ernest Electro Today

If your business could stand to benefit from sourcing a high-quality multicrusher for its unique processes, why not get one from us at Ernest Electro Engineering. Contact one of our representatives for further details today, or visit our website for more information on sourcing one for yourself.

What Must I Consider When Choosing a Borehole Pump?

There is a lot to think about when choosing the right borehole pump for your uses. You have to consider the lay of the land, your own budget, the depth of the borehole itself and much, much more. This can make selecting and installing a pump difficult. However, fear not, we are here to tell you exactly what you need to think about when doing it, to ensure that you get it right the first time, in no time.

What Will You Use the Pump For?

The application of your pump will have a lot to do with what type of motor you select, and so this is a good place to start when making your decision. Applications may include garden irrigation, filling a reservoir or for general household use. You may need a more specialised application that requires a higher capacity, such as dewatering mines and irrigating crops or watering livestock. All of these applications have specific requirements when it comes to the pump that you choose.

How Much Water Does the Pump Need to Move?

This is closely tied to the boreholes application. It makes sense that the more flow required, the greater the pressure needed. Some applications might need more pressure over flow, or vice versa. To make the right choice, you will need to consider your needs for supply very carefully.

How Far Does the Water Need to Go?

The distance that the water needs to be pumped at will have a direct effect on which pump you opt for. Firstly, there is the depth of the borehole to consider, since deeper ones need stronger pumps to be effective. Secondly there is the distance travelled along a horizontal distance once it has been drawn from the earth. Thirdly, you will want to consider ground elevation, since elevation at the water’s end-point will require more power for pumping.

Contact Ernest Electro Engineering for Details

While this will give you a good starting point, there is a lot to consider when selecting a borehole pump. To get it right the first time, contact a representative from Ernest Electro Engineering, a leading supplier of borehole motors in Johannesburg, for more details.

The Benefits of Oddesse Submersible Motor Pumps

There are just some jobs that your standard pump cannot do, and this can be for a large variety of reasons, such as environmental conditions or different pressures, or the type of work that the pump would have to do. This creates the need for the creation of other pumps, so that they can do the jobs that other pumps cannot. This had led to a market that has now got a very wide variety of pumps that are all designed to do different jobs for different conditions. It might get overwhelming to understand why certain pumps could be better to use than others, so here are the benefits of an Oddesse submersible motor pump.

The Uses of Oddesse Submersible Motor Pumps

A pump like the Oddesse Submersible Motor Pump is great for a few reasons, one being that is is suitable for a variety of environments. There are examples of the different uses of this kind of pump:  domestic water supply in water works, dewatering in mining and underground construction, saltwater delivery, pressure boosting systems, and it is great for water usage that is not just saltwater or seawater but also freshwater and brackish water. The applications are quite large in number as it is a versatile piece of equipment.

The Benefits of Oddesse Submersible Motor Pumps

There are a number of benefits that accompany a pump like this, other than the wide variety of its uses, this includes a small outer diameter, it has low operation costs, there are long intervals between maintenance, thus there will be minimal amount of time or money spent of repairs for the pump, the pump is environmentally friendly as well as recyclable. The pump has the ability to be installed either vertically or horizontally, suiting your needs better.  The pump allows you to make adjustments with the frequency converters.

Ernest Electro

One does not have to look far or wide to find such a versatile and handy pump. Ernest Electro is here to help you get the best Oddesse Submersible Pump or other great pumps to help you complete your projects and get your work done. Visit their website today to find out more about this pump, and place your order!

Electric Motor Rewinding

Electric motor units perform a great amount of work in today’s times. They keep many different electronic devices working and running properly. Various types of electric motors are used to make our lives run smoother, however, they can cost a pretty penny to replace. Luckily, electric motor rewinding can be done in order to get your motor working again without the high price tag.

There are many factors and reasons to consider when deciding whether to have your motor rewound instead of purchasing a new one. Professional care is needed when rewinding an electric motor as it is delicate. Even a small error throughout the process could result in quite a loss. It is by no means a simple task to rewind a motor, it is best to have a professional take a look and handle the rewinding process. At Ernest Electro we have professionals who are happy to help rewind your electric motors.

How do you know electric motor rewinding is for you?

When a motor’s insulation is damaged or ruined, the electricity will begin to transfer from winding to winding which will cause excess heat and damage the motor. Power problems often also result in the motor being damaged. Ensuring you take care of the routine maintenance which includes rewinding when necessary is going to extend the life and the productivity of your electric motor.

When rewinding a motor, first the motor housing is removed in order to expose the windings. Then the wire from the tabs on the brush pads is carefully removed. The wind free coils then get cut from the motor. The insulation is inspected to ensure it is still in good shape, then the armature is rewound. The exact same winding pattern is recreated and the number of coils around each of the windings. The windings are then connected and the wires double checked to ensure that the tabs aren’t touching. Once all of the above is done, the motor housing is then reassembled.

To rewind an electric motor is very tedious and quite difficult. Unless you are experienced, having a professional in the field take on the task is the way to go. At Ernest Electro we specialize in the rewinding of many different electric motors. Visit our website on www.ernestee.co.za/ for more information.

Difference between ac and dc electric motors

An electric motor is a machine that turns electrical energy into mechanical energy. An electrical signal is applied to the input of the motor, and the output of the motor produces a distinct amount of torque related to the characteristics of the motor. If you compare the attraction and repulsion of the north and south poles of a bar magnet, you’re on your way to understanding what has to happen within the motor. To achieve rotation, there has to be some interaction between magnetic flux produced by electromagnetism within the motor. DC motors and AC motors accomplish this task in different ways.

DC machines can be classified as self-excited, independently excited, permanent magnet (PM), and brushless. Self-excited machines can be further classified as shunt, series, and compound. Compound machines can be further classified as cumulative and differential. Cumulative and differential machines can be further classified as long shunt and short shunt. There are is an array of electrical configurations for a DC machine.

AC machines can be classified as induction, wound rotor, and synchronous. Induction motors can be further classified as 3-phase and single-phase. A 3-phase induction motor can be further classified as delta wound or wyes wound. Single-phase motors can be further classified as split phase, capacitor start, capacitor start/capacitor run, shaded pole, repulsion start, and universal. There are several varieties of AC motors.

The induction motor is frequently referred to as a squirrel cage induction motor. This is due to the fact that the rotor is constructed in a manner similar to a squirrel’s cage. An induction motor has a rotor rotating part and a stator stationary part within the motor covering. As soon as, an AC signal is applied to the stator winding, a rotating magnetic field is produced. This rotating magnetic field induces a signal in the rotor, which then also generates a rotating magnetic field. The interaction of these rotating magnetic fields causes rotation. This is a vital principle to keep in mind because in the case of a DC motor, the magnetic field is not time varying due to the applied signal.

For more information go to Ernest Electro, they offer equipment such as AC and DC motors and more.

About Side Channel Pumps

The side channel pump is a niche product that is somewhere in between a centrifugal pump and a displacement pump. Initially, these types of liquid ring pumps we designed to pump gas, air and liquid mixtures. A side channel pump can be used for many different applications.

A side channel pump will generally have these following characteristics:

• Offer the ability to transport gas without any interruptions to the fluid flow or damage to the bearings.
• They have automatic self-priming capability
• Offers maximum power consumption that its highest head and lowest flow rate.
• Narrows columns (side channels) are not suitable for abrasive particles in the fluids.
• A very low suction head (NPSH) is required.
• A steep capacity-head (Q-H) curves ideal for pressure-dependent system regulation.

When the pump is started, it initially functions just like a displacement pump because of its self-priming capability, but once the side channels are filled with liquid, it will begin to operate like a centrifugal pump does. The centrifugal effect will then cause a collection of liquid in the outer region of the side channel and in the impeller cells, this forms the liquid ring that is necessary for the self-priming process. The inner region is where the gas builds up. A side channel pump is also able to operate as vacuum pump for a certain amount of time before the auxiliary liquid starts to heat up and then finally evaporates.

Besides the pumps self-priming capability, it has the added advantage of also being able to handle big gas flows with the liquid. In some processes, it’s essential that the pump can, as least temporarily, evacuate vapours and gasses from the process without the liquid flow being interrupted. The standard radial centrifugal pump has a very limited capacity to transport gas within the medium. Even with a lower gas content, the liquid flow can immediately damage or interrupt the pump bearings because of dry running.

The pressure build-up that is caused by the sum of the individual pulses during the liquid movement will create an internal multi-stage effect, even when there is only one impeller. A lower potential pump speed is possible because of higher pump heads thus helping to reduce the pump’s NPSH requirement compared to a high-speed pump. With a lower pump speed, you will have the additional advantage that part load performance, mechanical loads and noise can be controlled better and the pump’s expected service life is then generally increased.

At Ernest Electro we specialise in a wide variety of pumping systems and solutions in Johannesburg. Visit our website on www.ernestee.co.za for more information.

Why Your Pool Needs a Pump

Having a swimming pool is a lot of hard work and entails plenty of upkeep; this is why there are companies that offer the service of pool maintenance. However, that does not offer the most effective means of keeping your swimming pool clean and inviting all day long. That is why there are swimming pool pumps and automotive pool cleaners. The swimming pool pump offers movement to the water in the pool in order to keep it in its best condition.

How Does the Pump Work?

The swimming pool pump, also known as a centrifugal pump, is a motorised piece of machinery that creates a vacuum for the pool, the pool cleaner or Kreepy-Krauly to act as an underwater vacuum that cleans the floor of the pool as well as creating water movement. The swimming pool pump is powered by a pool motor, which allows the pump to function and create that vacuumed suction. These two products need to be compatible otherwise the motor or the pump will have a shorter lifespan.

Why Get A Swimming Pool Pump?

By getting a swimming pool pump, you are allowing your pool to have a self-cleaning function. This self-cleaning function allows you the freedom to complete other tasks and activities throughout the day and week that you would not have had the chance to get to if you had to clean your pool about once or twice a day, or alternatively, you would neglect your pool in order to give your attention to those other tasks.  A pool pump would assist in catching all the dust and floating debris into a filter, which will need to be checked and cleaned out, manually, twice a week.

Getting a Pool Pump

Swimming pool pumps are not one size fits all, the size and placement of the pool will depend of the pump and motor size. The location will determine how much debris will need to be cleaned out of the pool on a daily or weekly basis. This will influence the size and strength of the pool pump. To find out about the best pool pump and motor needs for your pool or to cater to any other water pump needs that you have, visit Ernest Electro.