Drainage pumps for water: types, device, how it works, the best models

Drainage pumps are indispensable assistants in solving many problems associated with the transport of water. Thanks to the compact dimensions and ease of installation, these “universal soldiers” will help in a short time to cope with any problem - from pumping unclean water from the well to draining the site.

In order for the unit to cope with the tasks entrusted to it, and the purchase was justified by uninterrupted operation, it is necessary to carefully consider the choice of instrument.

We will show you how the drainage pumps for water work, which models it is appropriate to use in any given situation. In addition, let us designate reliable manufacturers of equipment and list the main selection criteria for drainage pumps.

The design of the drainage pump

The design of any drainage pump, whether domestic or foreign, has a similar configuration and the general principle of operation. An electric motor with a pump unit is placed in the housing of the unit.

The working elements of the electric motor are the stator, rotor and bearing shields. A leading working “organ” - a centrifugal impeller, referred to as an impeller, is planted on the rotor shaft.

Suction openings are provided in the pump unit. The diameter of these inlets determines the maximum amount of solid particles that the device is able to pass through.

For the safety of movable mechanisms, the pump unit of the unit is supplied with:

• thermostat - turns off the device when the engine is warming up until the critical temperature is reached;
• float switch - reacts when the level of the processed liquid is reduced to a critical value.

The float switch is a set of sensors enclosed in a sealed polymer box. Thanks to the air inside the box, like a float, it is always on the surface of the water and moves after its level.

Today, it is increasingly possible to meet devices equipped with new technology aqua-sensor. They are effective when it comes to arranging narrow tanks, in the cavity of which the placement float switch does not seem possible.

With this built-in regulator, it is convenient to set the desired water level to automatically turn on and off the device. The minimum level can reach revenge of only 5 mm.

If the drainage unit is used regularly, hard pipes are supplied to it. In the case of periodic use of the pump to connect enough flexible hoses.

The principle of operation of the unit

By siphoning off water, a drainage pump diverts it from a filled tank or a flooded room to a nearby facility. At the same time, the processed liquid first enters the working chamber, and then, due to the pressure created by the action of the pump wheel, it moves toward the outlet nozzle.

Thanks to the design of most drainage pumps, in which the impeller has a semi-open design, the units are capable of pumping large portions of fluid in the shortest possible time.

The pumped liquid in parallel performs the function of cooling the engine. Due to this, the probability of overheating of the pump during prolonged operation is reduced to zero. But for the same reason, manufacturers of drainage pumps impose a limitation on the maximum temperature of pumped water. For most models, it should not exceed 50 ° C.

Equipment that is able to work in non-standard conditions and hot environments is also on sale. But such equipment is much more expensive.

Drainage pumps are able to work effectively in environments with different degrees of contamination.

The units presented on sale are divided into three categories:

1. For clean and slightly polluted water. Pumped water with the inclusion of particles with a maximum size of 5 mm. They are used to carry out water intake from water downhole wells, emptying pools and pumping water from rain tanks.
2. For moderately polluted waters. The size of the solid particles transported with water does not exceed 25 mm. They are used to empty drains, drainage wells.
3. For dirty liquid with inclusions of 38 mm. They are flooded to empty their wastewater traps, pumping dirty water when flooded.

The performance of devices intended for clean and slightly polluted water ranges from 83 to 230 l / min. And the supply of pumped liquid can reach from 5 to 12 m.

For pumping dirty water, including gravel and similar particles with a diameter of 10 to 15 mm, use units with a capacity of 37 to 450 l / min. They are able to provide water to a height of 5 to 22 meters.

Industrial drainage models created by for work with sewer systems, can "digest" particles up to 120 mm in size.

Drainage plants are able to most effectively work only with liquid, in which the minimum content of solid elements.

With contaminated water saturated with solid waste, cope fecal pumps with a grinder.

Classification of pumps by type

The variety of pumping equipment is divided into two categories: surface and submersible units.

Surface Models

Surface units are designed for installation above the tank. The housing of this type of device is placed on a flat surface in a dry place. The water is pumped out through a hose lowered into the tank: a PVC pipe or a rubber hose.

Any surface model has two pipes:

• input - ensures the flow of waste water from the filled tank;
• output - removes wastewater outside the depleted structure.

Such devices can operate in automatic mode. For the implementation of automatic operation, a float mechanism, which reacts to the liquid level in the tank, is connected to the inclusion tumbler.

It is immersed in the pumped liquid along with the hose. When the water rises above a certain mark, the sensors of the float, which controls the start of the pump, are activated.

The main advantages of submersible units are:

• ease of installation and disassembly;
• maintenance of the device is reduced only to timely cleaning and lubrication of parts.

But such units are not suitable for deep sources. They are designed to work with an absorption height of 8-12 m.

It should also be borne in mind that when connecting such a pump to the sewer system, you need to know the exact cross-section of the pipeline, since the unit is attached to it with the help of pipes.

Submersible drainage devices

Submersible devices act in much the same way as surface drainage pumps work. But they are more intended for pumping water from deep trenches or cleaning wells.

Pumping sewage is carried out by the pump itself without using hoses and nozzles. A strainer located in the bottom of the pump protects the elements of the unit from hard rocks, sand and insoluble particles.

The maximum depth of immersion of pumps for different models usually does not exceed 50 m. But they cannot be used when emptying small tanks and reservoirs, the depth of which does not reach 20 m. In order for the submersible devices to work in shallow trenches, it is necessary to apply additional engine cooling. water

The depth of installation of the unit depends on the type of tank. But there is a simple pattern: the lower the submersible pump is located, the easier it will work with it.

Among the main advantages of devices of submersible performance is to highlight:

• high power and performance compared to surface aggregates;
• possibility of draining deep tanks several tens of meters;
• quiet run - in the process of operation, the units immersed in the capacity produce practically no noise.

A feature of installations of this type is that they operate automatically. Equipping the device with a float mechanism or a plastic bubble ensures uninterrupted pump operation in automatic mode. It shuts off the pump motor when it reaches a predetermined water level.

The constant operation of the device under water requires reliable isolation of the automation and sealing of the electric motors of the device. Therefore, in the manufacture of submersible units, only corrosion resistant materials are used that are able to withstand mechanical damage.

Depending on the destination and the perceived loads, the material for manufacturing nodal parts can be:

• polymers and engineering plastics;
• electrotechnical, alloyed and carbon alloys and steel.

In expensive models for sealing the motor of the device are used seals made of ceramic cuffs, or with an oil lock.

The only disadvantage of immersion devices is that for maintenance and drainage pump repairIt has to be removed from the tank to the surface. And due to the tightness of the case, it is quite problematic to maintain and repair them.

Types of pumps to destination

Depending on the power of the devices and their area of ​​application, drainage pumps are conventionally divided into two types: domestic and industrial.

Consumer units

Drainage pumps, designed for domestic use, have a wide range of applications.

They are used by:

• for pumping water from flooded cellars and cellars;
• the devastation of technical wells;
• pumping water from the pools;
• watering the garden from the reservoir or barrels.

Single-phase low-power pumps have an average capacity of 800 l / minute and are capable of moving the water extracted from a tank, pond, well to a height of up to 25 m.

For domestic needs most often acquire drains, the body of which is made of stainless steel or reinforced polymer. They are capable of pumping water with the inclusion of solid impurities up to 10 mm in size, the ratio of which is 10% of the total volume.

Pumps for industrial purposes

Industrial drainage pumps have higher power and performance. Motor pump and diesel pump units are widely used by utilities, construction companies and the Ministry of Emergency Situations.

With their help, produce:

• pumping out sewers and blocked pipelines;
• elimination of emergency flooding;
• industrial drainage;
• drainage of collector ditches and other objects.

On an industrial scale, drainage pumps are most often used by electric motors placed in cast iron housings. The powerful radiator of such devices provides effective heat removal, and the cast-iron case protects against deformation with significant heat generation.

Industrial three-phase pumps are characterized by a suction rate of up to 1500 l / min. They are able to raise the processed water to a height of about 150 m.

Such models have a more complex design. For maintenance, they require the involvement of a specialist.

Leading manufacturers of drainage pumps

The market of pumping equipment today offers a wide selection of drainage units of various manufacturers, both domestic and foreign.

Among buyers, the most popular models are those produced under such trademarks:

• Grundfos - The Danish company specializes in the production of pumping equipment, including electric motors and components for them. The wide model range includes both external and immersion devices designed for pumping clean and dirty water of various temperatures. The units manufactured under this brand belong to the high-priced segment, since the prices for models are one and a half times higher than the average mark.
• Perdollo - an Italian company, guided by the principle of helping humanity in solving problems of water supply, produces new generation pumps. There are hundreds of models in the manufacturer's catalog that differ in purpose, design and performance. Wear-resistant and reliable devices manufactured by them, despite their rather high cost, have a lot of positive customer feedback from different parts of the world.
• Wilo - The German brand, which appeared on the domestic market more than two decades ago, is famous for introducing the latest technologies and modern design. The company produces high-quality equipment for water supply and drainage systems, as well as ventilation and air conditioning.

The enterprises of each of the listed companies have a multi-stage quality control. Their products comply with international quality and safety standards.

Recommendations on the choice of equipment

The first thing you should aim at when choosing a unit is the conditions of its use and the degree of water pollution.

When choosing drainage equipment for water should focus on the technical specifications of the product:

1. Performance. It is determined on the basis of the amount of work that the unit must perform. That is, how much liquid he must pump out during the specified time period. Emphasis should be placed on the most complex process.
2. Head To determine this parameter, you should know the approximate height and distance over which you plan to transport water. This indicator is calculated as the difference between the mark of water outflow from the nozzle and the depth of immersion of the unit.
3. Pumped medium. The maximum allowable size of solid inclusions to be pumped with water is specified in the device specification. In models designed to work with polluted water, the dimensions of the working chamber should be such as to ensure the smooth passage of fractions.
4. Maximum temperature threshold. When choosing an immersion model, be guided by the maximum temperature threshold of the pumped liquid, since the engine of such a unit is cooled by transferring thermal energy to the transported liquid. In most cases, the maximum water temperature threshold is 50 ° C.

The maximum capacity of household units is 180 l / min. This is quite enough to drain the tank or remove water from the cellar. In order to be able to pump out water from the bottom of the tank or well in the optimum mode, choose models whose suction openings are located at the bottom.

When calculating the required power, the parameter should be taken as the basis that one meter of vertical water intake will correspond to ten meters horizontally.

When selecting a model, consider also the condition of the surface where the equipment will be placed. Surface drainage pump is better placed in the pit size of 40x60 cm. This will avoid the spreading of water on a flat surface.

If you use automatic, assuming a vertical arrangement of the float, then the surface will remain completely dry. After all, with a well-executed setup, float mechanisms work properly and reliably.

Regardless of the type of model intended for pumping clean liquid, it should be borne in mind that you should not operate it near the silted or sandy bottom of a reservoir. Particles entering the device will clog it, which may adversely affect the service life of the unit.

Additional information on the design features of drainage pumps and tips on choosing equipment are given in this article.

Conclusions and useful video on the topic

The principle of the drainage equipment:

Rules for proper selection of the drainage pump:

Classification of drainage pumping equipment:

The drainage pump is a versatile machine that can perform several tasks. Coming right to the choice of model, you can use one pump in several processes, so you get an excellent opportunity to use the unit for a long time and fruitfully.

Looking for an efficient and reliable drainage pump for water? Or have experience using such installations? Please leave comments on the article and share your impressions about the use of drainage pumps.