Design and principle of operation of a water pump and pump: types of equipment, characteristics, operation

Types of industrial pumps

Editorial

Promdevelop editorial team

The main purpose of industrial pumps is to use them for pumping water, oil products, food liquids, soil, sand, and various chemicals.

Applications of industrial pumps :

• if it is necessary to force the circulation of liquids in all kinds of production devices;
• for cooling, heating, thermo- and moisture regulation;
• to maintain constant pressure;
• for watering, irrigation and drainage in agricultural technology;
• in the food industry;
• in water supply systems (see Industrial water pumps).

Types of industrial pumps:

• monoblock;
• console-monoblock;
• vertical design;
• horizontal;
• “in-line” (when the supply and outlet of the medium are at the same level);
• without contact of the rotor with the medium (“dry”);
• with a rotor and impeller in the pumped liquid (“wet”);
• submersible pumps.

Vortex pumps - application and description

Vortex pumps are used to pump clean water without abrasive inclusions and liquids whose chemical composition is safe for the device. Vortex pumping units are quite reliable and relatively simple.

Application of vortex pumps

Vortex pumping units are used in the following systems:

• in irrigation systems;
• in sewerage and water supply units;
• in industrial and technological processes.

Vortex installations are also used in fire suppression, chemical water treatment, heating and ventilation, as well as in oil refineries and alcohol factories, for filling and emptying tanks.

Construction of a water supply system

If you decide to organize your home plumbing yourself using a reliable water pump, make sure that the connection is made correctly.

1. First you need to connect the hose to the pump and lower the submersible equipment into the well. If you choose a surface model, then secure the suction pipe and lower it into the tank.
2. After this, the trench should be prepared. Its depth should not exceed the freezing level of the soil. This is where the water pipe is laid. To fix it with the pump pipe, use an appropriate adapter. To install a surface pump, you should give preference to a caisson. An alternative option involves extending the suction pipe directly into the basement of the house where the pumping equipment is installed.
3. Next, you need to run the pressure line into the basement. Here it is connected to a hydraulic accumulator. Such equipment is responsible for maintaining constant pressure and uninterrupted water supply.

To organize water supply in a private house, it is necessary to use a water pump, which is immersed in a well. Such equipment is available in various models, which means you can choose a unit taking into account personal preferences and the characteristics of local water.

Seleznev Gennady Antonovich

Screw pumps

Screw pumps are used to move products of high viscosity, insufficiently liquid, non-fluid water treatment media, for wastewater treatment, for any highly viscous, difficult-to-flow products.

Moyno screw pumps - new generation equipment

They are equipped with a screw, with the help of which the mixture enters the suction cavity. This makes it possible to pump particularly difficult-to-flow substances. At construction sites, screw units are used for pumping cement-sand mixtures, for injecting cement and complex polyurethane compositions, and for supplying primers, adhesives and adhesive paints.

Applications of industrial screw pumps:

• food industry;
• sewerage systems;
• capital construction;
• production of building materials.

Circulation pumps - operating principle

A circulation pump is a unit that is installed directly into a pipeline to force liquid or coolant through it. Circulation units are preferably equipped with a “wet rotor”, which is placed in this liquid. Lubrication and cooling of its moving parts occurs with the same flowing liquid, thanks to which such pumps operate for a long time, silently and reliably. Due to the action of centrifugal force, water is thrown into the pipeline from the pump housing. They differ in power, purpose, design features.

Circulation pump units are used in heating and cooling systems.

Circulation pump for heating

The circulation pump is one of the most important elements of heating systems, without which the operation of the latter is either impossible or has extremely low efficiency. Forced circulation of the heat exchanger (water, working medium) using the unit reduces fuel consumption, increases heat transfer and increases the overall temperature in residential or non-residential premises.

Installing a circulation pump

Installation method:

• on horizontal pipelines - with the electric motor up;
• on vertical pipelines - so that the motor axis is in a horizontal position.

Installation of a circulation pump

No additional supports are needed to provide rigidity; the pump operates with minimal vibration.

Areas of application: hot water supply and heating systems for residential buildings, public and administrative buildings, industrial buildings.

Operating principle

Centrifugal pumps are one of the most common machines in the industry. In terms of quantity, they are second only to electric motors. Because Since electric motors are used to drive pumps, it can be said that the lion's share of the world's electricity is spent on transporting liquids by centrifugal pumps.

Centrifugal pumps get their name from the way in which energy is transferred to the fluid.

As liquid is introduced to the pump, it comes into contact with the rotating impeller and is forced into the discharge pipe by centrifugal force through a specially shaped cavity called a spiral casing . All centrifugal pumps operate on this principle, but there may be design differences among them.

The pump transfers kinetic energy to the fluid . Kinetic energy refers to the speed of the fluid . Speed ​​is only half the equation.

Fig. 1 – Centrifugal pump

The liquid enters the pump through the center of the wheel through the suction port. The friction between the fluid particles and the impeller causes the fluid to rotate. For example, how friction between the road and the rubber of a tire makes a car move.

The impeller pulls the fluid particles so they rotate when they come into contact with them. The fluid is pushed out of the wheel by centrifugal force - a phenomenon that pushes any object away from the center of the circle towards its borders. This is how the fluid receives kinetic energy from the wheel.

Therefore these pumps are called centrifugal .

The amount of energy transferred to a fluid depends on three factors:

• liquid density:
• impeller rotation speed:
• impeller diameter:

After the impeller, the liquid enters the cavity of the volute housing, from where it enters the pressure pipe.

Pressure . The pump must also produce positive pressure to meet the system requirements. Usually this is overcoming gravity when lifting liquid from a lower level to a higher one, and the frictional resistance of pipelines.

Simply put, pressure is the ability to complete a task . And the speed of the fluid is how quickly it will be completed.

Pumps must convert dynamic pressure into static pressure.

As the fluid passes through the spiral casing, it slows down as the passage area increases, because the productivity or the amount of fluid pumped over time depends on two factors: the first is the speed of the fluid, the second is the size of the cavity through which it moves .

If the flow is constant, then an increase in the flow area leads to a decrease in speed and an increase in pressure . Upon reaching the pressure port, most of the kinetic energy is converted into pressure.

By the way, read this article too: Low-pressure hydrocirculating VSS

If the speed drops, the pressure increases.

Vacuum pumps

Vacuum pumps are used in any technological chains of industry, medicine and pharmacology, where the creation of low pressure or vacuum zones is required. Often used in mechanized dairy farming as the main component of milking machines. The main advantage is the ability to ensure sterile cleanliness during the pumping process.

Types of industrial vacuum pumps:

• dry vane-rotor;
• oil;
• one- and two-stage;
• monoblock;
• water ring

There are a number of special models of vacuum devices for use in a specific industry, in order to solve specific narrow technological problems.

Control unit - what it is and how it works

The main advantage of the pumping station is automation. That is, you don’t need a special person to monitor the pressure in the network and turn the device on and off. All this is done automatically. And it consists of two main semi-automatic components:

• pressure gauge - a device that measures the pressure in pipes; when it is low, a signal is sent to start the pump;
• relay - consists of two springs that open and close the circuit to apply pressure and remove it. It works based on the liquid level in the tank.

It is important to pay attention to the factory settings, as they usually correspond to the values ​​of the shut-off valves, but in some cases it is necessary to change the extreme values ​​​​on the relay.

An additional element is the flow controller. When there is no water in the system or the flow becomes smaller for some reason, the device signals this. Its actions lead to minimizing the risk of engine overheating.

Below is a diagram of the electric pump control unit:

Centrifugal pumps - types and applications

Operating principle: pressure creates centrifugal acceleration, which occurs when the impeller acts on the liquid medium.

Centrifugal pumps are predominantly spiral in shape. Create a uniform, continuous flow. They can be single-stage or multi-stage - with several impellers.

Types of centrifugal pumping units:

• horizontal and vertical;
• console;
• low, high, medium pressure;
• single and double suction;
• with spirals or blades;
• superficial, deep, submersible.

Application of centrifugal pumping equipment:

• to eliminate fires - fire protection;
• for pumping alkaline solutions (alkaline);
• for pumping petroleum products (oil pumps);
• for working in aggressive media (chemical);
• for soil suction (suction dredgers);
• used in temperature control systems.

Ejector

The greatest depth from which surface vortex and centrifugal pumps can lift water is 8-9 meters; it is often located deeper. To “get” it from there, an ejector is installed on the pumps. This is a specially shaped tube that, when water moves through it, creates a vacuum at the inlet. So such devices also belong to the category of self-priming. An ejector self-priming pump can lift water from a depth of 20-35 m, and this is more than enough for most sources.

Connection diagram for a remote ejector for wells of different diameters - two-inch on the right, four-inch on the left

The disadvantage is that in order to ensure operation, part of the water must be returned, therefore, productivity is significantly reduced - such a pump may not provide a very large water consumption, but no less electricity is spent to ensure operation. When installing an injector in a well or well of sufficient width, two pipelines are lowered into the source - one supply of a larger diameter, the second, return, of a smaller diameter. An ejector is connected to their outputs, and a filter and check valve are installed at the end. In this case, the disadvantage is also obvious - double pipe consumption, which means a more expensive installation.

In small-diameter wells, one pipeline is used - the supply one, and instead of the return line, the well casing pipe is used. In this way, a rarefaction zone is also formed.

Gear pumps type NSh - main characteristics

NSh gear pumps have a simple design and lower cost compared to plunger pumps. They are designed for use in volumetric hydraulic drive systems at low and medium operating pressures. For most models, the permissible operating pressure does not exceed 200 kg/cm. This is enough to work in the hydraulic systems of municipal and agricultural machinery, loaders and excavators. There are two key parameters for NSh gear pumps - operating pressure and productivity. The period of continuous operation for NS 1 is 5 thousand hours. depending on the intensity of use. Operating with clean working fluid extends service life. The efficiency of any model is not lower than 80%.

The shaft bearing bushings have a special design that allows them to compensate for wear. The working fluid is supplied to the end of the bushing and ensures its automatic pressing against the shaft even after significant wear. Four connections are sealed with such movable bushings (two on each gear shaft). The NSh industrial pump can be operated in hydraulic motor mode. In this case, the pipeline is screwed to the third pipe on the housing, which is intended for leaking working fluid.

Design of NSh pumping units

Structurally, the NS gear unit is made in a crankcase with two fittings, a drive shaft and a cover. The connections of all elements are sealed with multi-component seals. The suction element consists of two gears of the same diameter with teeth of a special profile. Sometimes there are special versions of pumps with three gears.

Installation

Produced on the power take-off box. Gear pumps operate at low rotation speeds, which must be taken into account. The range is 1500 – 3000 rpm. Any equipment of the NSh type can be operated at lower speeds, which will have a positive effect on its service life. Especially for power take-offs of various designs, NSh pumps are produced in both left and right directions of rotation.

The connection to the power take-off shaft is splined. For reliable safe operation, a safety valve is installed together with the pump.

Water pump

The shape of the blades can be either straight or angled, which affects the rotation speed. In high-speed pumps, the vanes come from bushings. Wheels with such blades are fastened with keys. Simple household low-power water pumps use riveted impellers.

The material for the manufacture of shafts of simple pumps is steel; for pumps with increased loads they are made of alloy steel with an alloy of chromium, nickel or vanadium; shafts for pumps pumping various acids are made of stainless steel. If the shaft is not balanced correctly, vibration may occur, which will cause serious damage to the pump.

Shafts are:

• Flexible: used in pumps with exceeding critical speed;
• Hard: used for quiet operation pumps without high speeds;
• Solid (the pump working shaft also serves as a motor shaft): installed in household pumps in which pump impellers are installed on the electric motor rotor.

Water pump bearings are made with cast iron liners, which are filled with babbitt. They are lubricated with liquid or thick lubricant. Bearings can be roller, ball, rubber, textile, etc. The casing also belongs to the body and is part of it. The rubber gasket between the casing and the body serves for sealing.

The oil seal serves to protect the engine from water and is located at the junction of the working chamber and the rear wall. The seals have soft padding made of cotton, paper or asbestos cord. On the liquid suction side, a water seal is installed on the oil seal. The oil seal device contains a coupling and a sealing ring, to which liquid flows from the discharge pipeline, preventing air from entering the working chamber.

Piston pumps - work progress

Piston pumps are capable of “dry suction”, unlike other designs. At the moment the piston lowers, a vacuum is created inside the cylinder, and the medium from the pipeline is sucked into it. The valves are activated, and with the subsequent movement of the piston, the liquid is forcefully forced out of the cylinder in the desired direction. The process is constantly repeated. To ensure that the liquid does not move “intermittently” and to avoid pressure pulsation, the pistons are combined into groups. Piston units come in single-acting and double-acting types. It is piston pumps that are able to provide the highest possible pressure.

Application of piston pumping devices:

• food, chemical industry;
• water supply;
• heavy engineering;
• mine construction;
• quarry mining.

What to consider during installation

An important point: even before installation, care should be taken to ensure the availability of rough water treatment. Otherwise, soil particles and other contaminants will enter the pump, which will quickly lead to equipment failure. It is best to order filtration systems from - there is a large selection and excellent quality.

Main table dispenser AquaPro 919H/RO (hot and cold water)

Main table dispenser AquaPro 929CH/RO (cooling/heating)

Floor dispenser AquaPro 311 (empty, without cooling)

You should also not forget about the check valve. It should be installed to prevent water from flowing back into the well when the system is not working.

Special attention should be paid to electrical safety, since the combination of moisture and electricity is not the best tandem. Be sure to install an RCD to avoid short circuits.

Otherwise, the station is very easy to connect.

Heat pumps - operating features

Heat pumps are used to select and transfer natural heat for heating purposes. The operating principle of heat pumps: the condenser is a heat exchanger that generates heat for the consumer, and the evaporator utilizes low-grade heat.

Types of heat pump units:

• vapor compression;
• absorption;
• electrochemical;
• thermoelectric.

Various designs of heat pumps can provide heat extraction from the air, rocks, soil, and reservoirs.

Based on the type of compressor, the devices are divided into open centrifugal, piston, semi-hermetic and hermetic.

Pressure parameters in the accumulator

For proper operation of household plumbing fixtures in the cottage water supply, it is necessary to maintain a pressure of 1.4–2.6 atmospheres. To prevent the accumulator membrane from wearing out too quickly, manufacturers recommend setting the pressure in it 0.2–0.3 atm higher than the tap pressure.

The pressure in the water supply of a one-story house is usually 1.5 atm. This figure should be used as a starting point when adjusting the hydraulic tank. But for larger residential buildings, the pressure must be increased so that there is water in all the taps farthest from the riser. This requires more complex hydraulic calculations, taking into account the length and configuration of pipelines, as well as the number and type of plumbing fixtures.

You can simply calculate the required pressure for the indoor water supply using the formula:

(H+6)/10,

where “H” is the height from the pump to the highest point of water supply to the plumbing on the top floor of the house.

However, if the calculated pressure in the autonomous water supply exceeds the permissible characteristics of existing plumbing and household devices, then when such pressure is set, they will fail. In this case, it is necessary to select a different layout of water pipes.

The pressure in the air part of the accumulator is regulated through the spool by bleeding off excess air or pumping it up with a car pump