Pumps with remote ejector
In the “Pumps” section we will consider another type of pump - this centrifugal pumps with a remote ejector. Applicable centrifugal pumps with remote ejector, for lifting water from a depth of up to 45 meters from wells or deep wells. They are used to create pressure in small water supply systems, as well as for filling containers and tanks. The effect of lifting water from such a depth is achieved through the use of a remote ejector. The ejector is lowered into a well or well and connected to the inlet pipes of the pump using two pipes.
Pumps with a remote ejector are used for pumping clean water. Abrasive or any other aggressive liquids can damage the pump. It is also prohibited to use the pump for pumping flammable, combustible or explosive liquids.
Technical characteristics and materials of pumps
Performance characteristics:
The temperature of the pumped liquid is no more than 35° C
Ambient temperature no more than 40° C
Maximum suction depth 45 m.
Noise level in continuous operation no more than 70 dBA
The pump is designed for long-term operation
Engine:
2 pole asynchronous electric motor, number of revolutions 2850 min -1
Insulation class F
Protection class IP 44
Materials:
The pump body is made of cast iron
The impeller is made of plastic (noryl)
The diffuser is made of plastic (noryl)
The remote ejector body is made of cast iron
Venturi tube and remote ejector nozzle are made of plastic (noryl)
The pump shaft is made of stainless steel
Mechanical seal - graphite/ceramic
Operating principle, installation and connection of centrifugal pumps with a remote ejector
The main difference between pumps with a remote ejector and self-priming and normally priming centrifugal pumps is that on the suction side of the pump there are two pipes for connecting two pipelines - supply and return. The supply pipeline, with a diameter of 1 1/4″, supplies water to the pump. The return pipeline recirculates water from the pump to the remote ejector; its diameter is one size smaller than the supply one and is 1″.
Remote ejectors are manufactured in two sizes for four and two inch wells (Fig. 1).
Remote ejector 4″ and 2″
The remote 4″ ejector consists of three parts: body (item 1), nozzle (item 2) and Venturi tube (item 3). The remote 2″ ejector consists of the same main parts as the four-inch one, plus it comes with a special adapter (item 5) for mounting on a well. When installing a remote ejector in a well, it is necessary to install a check valve with a mesh (item 4).
(Fig. 2) shows installation diagrams of centrifugal pumps with a remote ejector for 4″ and 2″ wells.
In four-inch wells, an installation scheme with two pipelines is used. For two-inch wells, a slightly different installation scheme is used. The ejector is mounted on the supply pipeline, and a casing pipe is used as the return pipeline. A check valve with a mesh (item 1) must always be installed on the suction pipe of the remote ejector.
The operating principle of pumps with a remote ejector is as follows. Part of the water supplied by the impeller to the pump is directed into the pressure pipeline (item 6), and the rest of the water through the return pipeline (item 4) returns back to the ejector (item 2). Due to water recirculation and the presence of a Venturi tube in the ejector suction chamber, a vacuum is created necessary for sucking water from the well. The amount of water entering the ejector is determined by the diameter of the nozzle. The incoming water is mixed with the recirculating water and the volume of water in the supply pipeline (item 3) increases. Then the process is repeated.
When installing pumps, the following requirements must be observed:
- The pump must be installed in an easily accessible, dry place protected from moisture and frost with the possibility of its inspection, maintenance, repair and replacement.
- The pump is mounted on a flat, horizontal surface that exceeds its dimensions.
- All pipelines supplied to the pumping equipment are installed without tension.
- It is recommended to install the supply and return pipelines with internal diameters corresponding to the suction pipes of the pump. Suction pipelines are installed without unnecessary bends, turns and as short as possible.
- It is necessary to connect the supply pipe so that it rises towards the pump to avoid the formation of air pockets. The inclination angle of the supply pipeline should be 1-2° below the pump level.
- Ensure absolute tightness of the supply and return pipelines from the pump to the remote ejector to prevent air leaks and airing of the pump.
- It is imperative to install a mesh on the ejector suction pipe. The suction valve must be lowered into the liquid by at least 30 cm to prevent the formation of a funnel during pump operation.
- It is necessary to install a detachable connection on the pump pressure pipe as close as possible to the pump, for the convenience of filling the equipment with water during the first start-up. Also provide on the pressure connection shut-off valves, for ease of equipment dismantling.
For normal operation of a pump with a remote ejector, it is necessary that the pump itself, the supply and return pipelines, be constantly filled with the pumped liquid. It is prohibited to put the equipment into operation without filling it with liquid. It is necessary to carefully check the pump itself and the pipelines for leaks; leaky connections lead to air entering the system, and as a result, equipment failure.
For more efficient use of this scheme of operation of the water supply system, it is necessary to constantly, overpressure to create liquid recirculation, therefore it is recommended to additionally install and in such systems.
Electrical connection of pumps with a remote ejector
The electrical connection must be made by a qualified electrician and in accordance with the Electrical Installation Rules (PUE). When making electrical connections, pay attention to the following:
- The supply voltage must correspond to the operating voltage of the pump indicated on the rating plate.
- The pump must be connected to the power supply using a socket with a grounding wire fed through an equipment protection device (RCD) with a rated leakage current of 30 mA.
- In pumps with single phase motor built-in thermal protection that disconnects the pump from the power supply if the engine overheats.
- For pumps with three-phase motors, it is necessary to additionally install them with a protection current equal to the rated current of the motor.
Scheme electrical connection shown in (Fig. 3)
Electrical connection of pumps with a remote ejector
Operation, maintenance and repair of pumps with a remote ejector
During operation centrifugal pumps with remote ejector do not require special Maintenance. During operation, it is necessary to ensure that the pump does not operate without water flow “dry running”. If there is no water, you must immediately disconnect the equipment from the power supply or install dry-running protection to avoid its failure. Find out the reason why the pump does not work and eliminate it.
In conditions where the equipment can be defrosted, it must be dismantled, drained of all liquid, washed clean water and place in a dry place. Before turning the pump back on, you need to check its functionality; to do this, turn the pump on and off for a short time of 1-2 seconds. After installation, fill it with liquid and check for leaks.
In the event of equipment failure, repair the pump only in specialized service centers. When performing equipment repairs, only original spare parts must be used.
To summarize, we can say that when correct operation, pumps with a remote ejector will last a long time and reliably throughout the entire period of use.
Thank you for your attention.
If desired, you can equip your house with autonomous water supply almost everywhere. But the main problem is the depth groundwater. If the water surface in the prepared well is at a level of 5-7 meters, then there are no special problems; you can use almost any type of pump that is suitable in terms of performance and power consumption. The situation is different with wells, where the water starts much deeper. In this case, an ejector for pumping station.
Natural limitations for operation are created by atmospheric pressure, water column pressure and the strength of the elements of the pumping station itself. To lift water from great depths it is necessary to use submersible pump or significantly increase the weight and dimensions of the equipment, from which it becomes simply incapacitated and consumes a huge amount of energy. To avoid such problems, it is necessary to use additional means to facilitate the rise of water, to push it towards the surface, which is why an ejector is needed.
The ejector is structurally a very simple device. The following main components can be distinguished in its composition:
- nozzle;
- suction chamber;
- mixer;
- diffuser.
The nozzle is a pipe, the end of which has a narrowing. The liquid flowing from the nozzle instantly accelerates, escaping from it at great speed. According to Bernoulli's law, fluid flow at high speeds exerts less pressure on environment. A stream of water from the nozzle enters the mixer, where it creates a significant vacuum along its boundaries.
Under the influence of this vacuum, water begins to flow into the mixer from the suction chamber. Next, the combined fluid flow through the diffuser flows further through the pipes.
In fact, in the ejector there is a transfer of kinetic energy from the medium with higher speed to a medium with lower speed. How can this be used in combination with a pump?
The ejector is included in the pipeline running from the well to the pump. Part of the water that rises to the surface returns back to the well to the ejector, forming a recirculation line. Escaping from the nozzle at tremendous speed, it carries with it a new portion of water from the well, providing additional vacuum in the pipeline. As a result, the pump spends less energy to lift liquid from great depths.
By using a valve installed on the recirculation line, you can regulate the amount of water flowing back into the water intake system, thereby adjusting the efficiency of the entire system.
Excess liquid not involved in the recirculation operation is supplied from the pump to the consumer, determining the productivity of the entire station. As a result, you can get by with a smaller engine and a less massive pumping part, which will last longer and consume less energy.
The ejector also makes it easier to start the system; a relatively small volume of water can create sufficient vacuum in the pipeline and initiate the initial intake of water so that the pump does not run idle for a long time.
Design and types of stations
Pumping stations can be equipped with an ejector in two ways. In the first, it is structurally part of the pump and is internal. In the second case, it is implemented as a separate external node. The choice of layout depends on the requirements for the pumping station.
Built-in ejector
In this case, the intake of water for recirculation, as well as the creation of pressure in the ejector, is created in the pump itself. This arrangement makes it possible to reduce the size of the installation.
A pump with an internal ejector is practically not susceptible to the presence of suspended matter in the form of sand and silt. There is no need to necessarily filter the incoming water.
The station is used to collect water from a depth of up to 8 meters. It creates sufficient pressure to supply a large farm, where water is mainly used for irrigation.
The disadvantage of the internal ejector is the increased noise level during operation. It is best to install it outside a residential building, preferably in a separate utility room.
The electric motor is obviously selected to be more powerful so that it can also provide the recirculation system. However, this comparison is only relevant in a situation with a well depth of up to 10 meters. At greater depths, pumps with an ejector simply have no alternative, except perhaps the submersible type, which requires a well with a large diameter.
Remote ejector
With a remote ejector device, an additional tank is installed separately from the pump, into which water flows. It creates the necessary pressure for operation and additional vacuum to lighten the load of the pump. The ejector itself is connected in the submersible part of the pipeline. For it to work, it is necessary to lay two pipes into the well, which imposes some restrictions on the minimum permissible diameter.
This design solution reduces the efficiency of the system to 30-35%, but allows water to be extracted from deep wells up to 50 meters, and also significantly reduces the noise of an operating pumping station.
It can be located directly in the house, for example in basement. The distance from the well can be up to 20-40 meters without reducing efficiency. Such characteristics determine the popularity of pumps with an external ejector. All equipment is located in one prepared place, which increases the service life, makes it easier to carry out preventive maintenance and configure the system.
Connection
In the case of an internal ejector, if it is included in the design of the pump itself, installation of the system is not much different from the installation of a non-ejector pump. It is enough to simply connect the pipeline from the well to the suction inlet of the pump and arrange a pressure line with associated equipment in the form of a hydraulic accumulator and automation that will control the operation of the system.
For pumps with an internal ejector, in which it is fixed separately, as well as for systems with an external ejector, two additional stages are added:
- An additional pipe is laid for recirculation from the pressure line of the pumping station to the ejector inlet. The main pipe from it is connected to the pump suction.
- A pipe with check valve and a coarse filter for drawing water from a well.
If necessary, a valve is installed in the recirculation line for adjustment. This is especially beneficial if the water level in the well is much higher than the pumping station is designed for. You can reduce the pressure into the ejector and thereby increase the pressure in the water supply system. Some models have a built-in valve for such a setting. Its placement and adjustment method are indicated in the equipment instructions.
An ejector is a device that is designed to transfer kinetic energy from one medium moving at a higher speed to another. The operation of this device is based on Bernoulli's principle. This means that the unit is capable of creating a reduced pressure in the tapering section of one medium, which, in turn, will cause suction into the flow of another medium. Thus, it is transferred and then removed from the site of absorption of the first medium.
General information about the device
An ejector is a small but very effective device that works in tandem with a pump. If we talk about water, then, naturally, a water pump is used, but it can also work in tandem with a steam pump, a steam-oil pump, a steam-mercury pump, or a liquid-mercury pump.
The use of this equipment is advisable if aquifer lies quite deep. In such situations, it most often happens that conventional pumping equipment cannot cope with providing the house with water or supplies too much water. weak pressure. An ejector will help solve this problem.
Kinds
An ejector is a fairly common piece of equipment, and therefore there are several different types of this device:
- The first is steam. It is intended for the suction of gases and confined spaces, as well as for maintaining a vacuum in these spaces. The use of these units is widespread in a variety of technical industries.
- The second is steam jet. This device uses the energy of a steam jet, with which it is able to suck out liquid, steam or gas from confined space. The steam that comes out of the nozzle at high speed carries with it the moving substance. Most often used on various vessels and ships for rapid suction of water.
- A gas ejector is a device whose operating principle is based on the fact that excess pressure of high-pressure gases is used to compress low-pressure gases.
Ejector for water suction
If we talk about water extraction, then an ejector for a water pump is most often used. The thing is that if afterward the water turns out to be lower than seven meters, then an ordinary water pump will cope with great difficulty. Of course, you can immediately buy a submersible pump, the performance of which is much higher, but it is expensive. But with the help of an ejector you can increase the power of an existing unit.
It is worth noting that the design of this device quite simple. Production homemade device also remains a very real challenge. But for this you will have to work hard on the drawings for the ejector. The basic operating principle of this simple apparatus is that it gives the flow of water additional acceleration, which leads to an increase in the supply of liquid per unit time. In other words, the task of the unit is to increase water pressure.
Components
Installing an ejector will greatly increase the optimal water intake level. The indicators will be approximately equal to 20 to 40 meters in depth. Another advantage of this particular device is that its operation requires much less electricity than, for example, a more efficient pump would require.
The pump ejector itself consists of the following parts:
- suction chamber;
- diffuser;
- narrowed nozzle.
Principle of operation
The operating principle of the ejector is entirely based on Bernoulli's principle. This statement states that if you increase the speed of a flow, an area of low pressure will always form around it. Because of this, an effect such as discharge is achieved. The liquid itself will pass through the nozzle. The diameter of this part is always smaller than the dimensions of the rest of the structure.
It is important to understand here that even a slight narrowing will significantly accelerate the flow of incoming water. Next, the water will enter the mixer chamber, where it will create a reduced pressure. Due to the occurrence of this process, it will happen that liquid will enter the mixer through the suction chamber, the pressure of which will be much higher. This is the principle of the ejector, if we describe it briefly.
It is important to note here that water should not enter the device from a direct source, but from the pump itself. In other words, the unit must be mounted in such a way that some of the water that is lifted by the pump remains in the ejector itself, passing through the nozzle. This is necessary so that it is possible to supply constant kinetic energy to the mass of liquid that needs to be lifted.
Thanks to work in this way, a constant acceleration of the flow of matter will be maintained. One of the advantages is that using an ejector for a pump will save a large number of electricity, since the station will not operate at its maximum.
Pump device type
Depending on the location, there may be a built-in or remote type. There are no huge structural differences between the installation locations, however, some small differences will still make themselves felt, since the installation of the station itself will change slightly, as well as its performance. Of course, it is clear from the name that built-in ejectors are installed inside the station itself or in close proximity to it.
This type of unit is good because you don’t have to allocate extra bed to install it. The installation of the ejector itself also does not have to be carried out, since it is already built-in; you only need to install the station itself. Another advantage of such a device is that it will be very well protected from various types of contamination. The disadvantage is that this type of device will create quite a lot of noise.
Comparison of models
Remote equipment will be somewhat more difficult to install and you will have to allocate a separate place for its location, but the amount of noise, for example, will be significantly reduced. But there are other disadvantages. Remote models can provide effective work only at a depth of 10 meters. Built-in models are initially designed for sources that are not too deep, but the advantage is that they create quite a powerful pressure, which leads to more efficient use of liquid.
The generated jet is quite enough not only for domestic needs, but also for operations such as watering, for example. The increased noise level from the built-in model is one of the most significant problems that you will have to take care of. Most often, it is solved by installing it in the ejector together with separate building or in a well caisson. You will also have to worry about a more powerful electric motor for such stations.
Connection
If we talk about connecting a remote ejector, you will have to perform the following operations:
- Laying an additional pipe. This facility is necessary to ensure water circulation from the pressure line to the water intake installation.
- The second step is to connect a special pipe to the suction port of the water intake station.
But connecting the built-in unit will be no different from normal process installation of a pumping station. All necessary procedures for connecting the necessary pipes or pipes are carried out at the factory.
Ejector - what is it? This question often arises among owners country houses and dachas in the process of arrangement autonomous system water supply The source of water entering such a system, as a rule, is a pre-drilled well or well, the liquid from which must not only be raised to the surface, but also transported through a pipeline. To solve such problems, a whole technical complex, consisting of a pump, a set of sensors, filters and a water ejector, installed if liquid from the source needs to be pumped out from a depth of more than ten meters.
In what cases is an ejector needed?
Before dealing with the question of what an ejector is, you should find out why a pumping station equipped with it is needed. Essentially, an ejector (or ejector pump) is a device in which the energy of motion of one medium moving at high speed is transferred to another medium. Thus, the operating principle of an ejector pumping station is based on Bernoulli’s law: if a reduced pressure of one medium is created in a narrowing section of the pipeline, this will cause suction into the formed flow of another medium and its transfer from the suction point.
Everyone knows well: the greater the depth of the source, the harder it is to raise water from it to the surface. As a rule, if the depth of the source is more than seven meters, then a conventional surface pump has difficulty performing its functions. Of course, to solve this problem, you can use a more productive submersible pump, but it is better to go the other way and purchase an ejector for a surface-type pumping station, significantly improving the characteristics of the equipment used.
By using a pumping station with an ejector, the liquid pressure in the main pipeline increases, while the energy of the fast flow of the liquid medium flowing through its separate branch is used. Ejectors, as a rule, work in conjunction with jet-type pumps - water-jet, liquid-mercury, steam-mercury and steam-oil.
An ejector for a pumping station is especially relevant if it is necessary to increase the power of an already installed or planned installation of a station with a surface pump. In such cases, the ejector installation allows you to increase the depth of water intake from the reservoir to 20–40 meters.
Overview and operation of a pumping station with an external ejector
Types of ejector devices
According to their design and operating principle, ejector pumps can belong to one of the following categories.
Steam
With the help of such ejector devices, gaseous media are pumped out of confined spaces and a rarefied state of air is maintained. Devices operating on this principle have a wide range of applications.
Steam jet
In such devices, the energy of a steam jet is used to suck gaseous or liquid media from a confined space. The operating principle of this type of ejector is that steam escaping from the nozzle of the installation at high speed carries with it the transported medium exiting through an annular channel located around the nozzle. Ejector pumping stations of this type are used primarily for rapid pumping of water from the premises of ships for various purposes.
Gas
Stations with an ejector of this type, the operating principle of which is based on the fact that the compression of a gas medium, initially under low pressure, occurs due to high-pressure gases, are used in the gas industry. The described process takes place in the mixing chamber, from where the flow of the pumped medium is directed to the diffuser, where it is slowed down, and hence the pressure increases.
Design features and principle of operation
The design elements of the remote ejector for the pump are:
- a chamber into which the pumped medium is sucked;
- mixing unit;
- diffuser;
- a nozzle whose cross-section tapers.
How does any ejector work? As mentioned above, such a device operates according to the Bernoulli principle: if the speed of the flow of a liquid or gaseous medium increases, then an area characterized by low pressure is formed around it, which contributes to the rarefaction effect.
So, the operating principle of a pumping station equipped with an ejector device is as follows:
- The liquid medium pumped by the ejector unit enters the latter through a nozzle, the cross-section of which is smaller than the diameter of the inlet line.
- Passing into the mixer chamber through a nozzle with a decreasing diameter, the flow of the liquid medium acquires a noticeable acceleration, which contributes to the formation of an area with reduced pressure in such a chamber.
- Due to the occurrence of a vacuum effect in the ejector mixer, a liquid medium under higher pressure is sucked into the chamber.
If you decide to equip a pumping station with a device such as an ejector, keep in mind that the pumped liquid medium does not enter it from a well or well, but from the pump. The ejector itself is positioned in such a way that part of the liquid that was pumped out of the well or well by means of a pump is returned to the mixer chamber through a tapering nozzle. The kinetic energy of the liquid flow entering the ejector mixer chamber through its nozzle is transferred to the mass of the liquid medium sucked by the pump from the well or well, thereby ensuring constant acceleration of its movement along the inlet line. Part of the liquid flow, which is pumped out by a pumping station with an ejector, enters the recirculation pipe, and the rest goes into the water supply system served by such a station.
Once you understand how a pumping station equipped with an ejector works, you will understand that it requires less energy to raise water to the surface and transport it through a pipeline. Thus, not only does the efficiency of using pumping equipment increase, but also the depth from which the liquid medium can be pumped out increases. In addition, when using an ejector that sucks up liquid on its own, the pump is protected from running dry.
The design of a pumping station with an ejector includes a tap installed on the recirculation pipe. Using such a valve, which regulates the flow of liquid flowing to the ejector nozzle, you can control the operation of this device.
Types of ejectors at installation site
When purchasing an ejector to equip a pumping station, keep in mind that such a device can be built-in or external. The design and principle of operation of these two types of ejectors are practically no different; the differences are only in the location of their installation. Built-in type ejectors can be placed in inner part pump housing, or be mounted in close proximity to it. The built-in ejection pump has a number of advantages, which include:
- minimum space required for installation;
- good protection of the ejector from contamination;
- there is no need to install additional filters that protect the ejector from insoluble inclusions contained in the pumped liquid.
Meanwhile, it should be borne in mind that built-in ejectors demonstrate high efficiency if they are used to pump water from sources of shallow depth - up to 10 meters. Another significant disadvantage of pumping stations with built-in ejectors is that they produce quite a lot of noise during their operation, so it is recommended to locate them in a separate room or in a caisson of a water-bearing well. It should also be borne in mind that the design of an ejector of this type involves the use of a more powerful electric motor, which drives the pumping unit itself.
A remote (or external) ejector, as its name suggests, is installed at a certain distance from the pump, and it can be quite large and reach up to fifty meters. Remote-type ejectors, as a rule, are placed directly in the well and connected to the system via a recirculation pipe. A pumping station with a remote ejector also requires the use of a separate storage tank. This tank is necessary to ensure that water is always available for recirculation. The presence of such a tank, in addition, makes it possible to reduce the load on the pump with a remote ejector and reduce the amount of energy required for its operation.
The use of remote-type ejectors, the efficiency of which is slightly lower than that of built-in devices, makes it possible to pump out a liquid medium from wells of considerable depth. In addition, if you make a pumping station with an external ejector, then it can not be placed in the immediate vicinity of the well, but can be mounted at a distance from the water intake source, which can be from 20 to 40 meters. It is important that the location of pumping equipment at such a significant distance from the well will not affect the efficiency of its operation.
Manufacturing an ejector and its connection to pumping equipment
Having understood what an ejector is and having studied the principle of its operation, you will understand that you can make this simple device with your own hands. Why make an ejector with your own hands if you can purchase one without any problems? It's all about saving. Finding drawings from which you can make such a device yourself does not present any particular problems, and to make it you will not need expensive Consumables and complex equipment.
How to make an ejector and connect it to the pump? For this purpose you need to prepare the following components:
- female tee;
- union;
- couplings, elbows and other fitting elements.
Almost everyone who was involved in the arrangement autonomous water supply, was faced with the problem of insufficient water supply to the suction pump. From the physics course we know that atmospheric pressure allows water to be supplied from a maximum depth of 9 meters. In practice, this figure decreases to 7 and even 5 m of confident delivery. An ejector for a pumping station will help solve the problem, allowing you to increase the water pressure. The industry produces such equipment, which is part of pumping stations and pumps.
Design and principle of operation of the installation
An ejector is a device that transfers the energy of a medium moving at high speed to another, less mobile one. In the tapering section of the apparatus, a zone of low pressure of one of the media appears, provoking the suction of the second medium into its flow.
This allows it to move and move away from the suction point, using the energy of the first medium to move.
Internal structure of the ejector. This equipment is used to provide additional meters of water lift and insure the pump or station against unwanted dry running in the event of a sudden drop in the well level
Installations with an internal ejector are intended for pumping water from shallow, no more than 8 m, wells, storage tanks, wells or reservoirs. A distinctive feature of the device is its “self-priming” ability, which allows it to capture water located below the level of the inlet pipe. Therefore, for the device to operate correctly, it is necessary to first fill it with water. The impeller of the device pumps liquid and sends it to the entrance to the ejector, thereby creating an ejection jet.
She accelerates as she moves along the tapering tube. Accordingly, the pressure inside the jet decreases. Thus, the pressure inside the suction chamber also decreases significantly. If you connect a pipe to the inlet pipe and lower it into water, it will begin to be forcefully sucked into the device. Next, the liquid is sent to the suction chamber, slows down and is directed through the diffuser to the outlet, gradually increasing its pressure.
Pumping station with external (left) and internal (right) ejector. Equipment with a remote ejector can be installed at a considerable distance from the well or well
Another type of surface installation is a pumping station with a remote ejector. They are distinguished by the presence of an external ejector immersed in the source of water supply. The design and scope of application of the installations are generally the same as those of analogues with an internal ejector. A significant difference is the ability to use the device at depths of more than 10 m. In addition, such pumps are extremely demanding on the conditions for installing an external ejector. The pipes connecting it to the pump must be installed strictly vertically, otherwise the inlet line may become air-filled and become inoperable.
It is most optimal to use such a device to work at a depth of 15-20 m, although some manufacturers indicate a maximum depth of 45 m. It is clear that with increasing lifting height, the operating characteristics of the pump deteriorate. In general, devices with an external ejector have lower efficiency than those with an internal one.
It is only 30%. But they allow you to get rid of the noise created by the device, and make it possible to place the installation several tens of meters from the well.
Self-production of an ejector
It is quite possible to make the simplest device yourself. To do this, you will need a tee of the required diameter and a fitting, which should be located inside this tee. If the fitting is too long, it will need to be cut or ground. If, on the contrary, it is short, then add a vinyl chloride tube required length, coinciding with the fitting in diameter. Since the device will need to be mounted on the pump, you will also need an adapter with angles that form the necessary rotation with the transition to the pipe.
Ingredients for self-assembly ejector: 1- tee; 2 - fitting; 3 - vinyl chloride tube; 4 - adapter for metal-plastic pipe; 5 - NxMP angle; 6 - angle НхВ; 7 - NxMP angle
The ejector manufacturing process takes place in several stages:
- Preparing the fitting. The hexagonal element of the part must be ground to form a cone with a base slightly smaller than the diameter of the external thread of the fitting. The threaded part is shortened; no more than four threads can be left. Then, using a thread-cutting tool, we straighten the damaged thread and continue it by approaching the conical part, so that the fitting can be easily screwed into the tee.
- Fitting ejector parts. Screw the fitting into the tee until it stops with the narrow part. In this case, the outlet hole should not extend beyond the middle hole of the tee by more than 1-2 mm. Besides internal thread the tee must be left with no less than 4 threads. If it turns out that the thread of the tee is missing, we grind down the thread of the fitting a little more. If the outlet hole of the fitting is short, we put a vinyl chloride tube on it, if it is long, we grind it off.
Assembling the device
- . We check the compliance of the parts and finally screw in the fitting, making sure to seal the threads with any suitable sealant. Next, we assemble the necessary adapter from the prepared elements for mounting on the pipe.
Scheme for connecting our homemade ejector to the pumping station line
An ejector is an indispensable device for increasing water pressure and providing protection against unwanted dry running of the supply unit. It can be purchased complete with a pumping station, or you can assemble it yourself. In any case, it will work for a long time and efficiently, ensuring an uninterrupted supply of water even from a deep well.
