home > Wall repair > Do-it-yourself spray booth with a water curtain. Thermal water curtains: principle of operation, installation methods, types. An example of a painting booth from furniture production

Do-it-yourself spray booth with a water curtain. Thermal water curtains: principle of operation, installation methods, types. An example of a painting booth from furniture production

Paint box - a room equipped for car painting. One of the key factors affecting the usability of a spray booth is the ventilation system.
The size of the hood, directly depends on the size of the paint

In the process of painting a car, fumes toxic to the human body are released from the paint and the solvent added to it, a paint fog is formed that impairs visibility and settles on the vehicle body. The supply and exhaust system replaces the exhaust air with fresh air, providing optimal conditions for painting the car.

From this article you will learn what a hood for a spray booth is, what filters it comes with and how to calculate the ventilation yourself. We will also give instructions, following which you can equip the hood in the paint box with your own hands.

Types of ventilation systems and their comparison

Painting a car is a work accompanied by the use of toxic substances, the application technology of which requires compliance with the temperature regime and maintaining the purity of the air at a given level. The hood is not only for the safety of the painter, but also for the quality of the painting process and the polymerization of the applied coating.

The paint garage hood must meet the following requirements:

Air supply temperature during painting - 20-30 degrees, air temperature during coating drying - 50-85 degrees;
The speed of the air flow is 1.3-1.5 m / s (at excessive speed, the paint sprayed by the spray gun is carried away by the air flow, which interferes with the work);
The rate of air renewal in the box is 5-150 volumes / hour (to accurately determine the required rate, the ventilation of the production room is calculated);
The air pressure in the box is 20-30 kPa higher than the natural atmospheric pressure of the environment;
The flow injected into the chamber is clean, without dust and mechanical impurities (an air filter is used for cleaning);
The movement of the air flow - from top to bottom, or with a minimum vertical deviation.

Based on the type of ventilation, paint boxes are classified into two groups:

single-engine;
Twin-engine.

Single-engine ventilation chamber, which performs the forced injection of fresh air into the box, while the exhaust air is pumped out naturally due to the pressure difference inside and outside the chamber. The supply holes are located in the upper part of the room, the air flow entering the box precipitates the paint mist down, then the vapors enter the exhaust nozzle and are discharged outside.

In twin-engine boxes, ventilation provides forced air supply and intake from the chamber, which provides efficient circulation and a large air exchange rate.

It is rational to choose a specific type of ventilation based on the size of the box and the amount of work carried out in it. If the chamber is operated during the whole working day, and dozens of cars pass through it, it makes sense to install two-motor ventilation. In small boxes, it is advisable to use single-motor systems - productivity will be sufficient, in addition, you will save on the initial cost of equipment and subsequent maintenance.

Supply and exhaust ventilation

A type of dual-engine systems is a supply and exhaust hood, which operates in 3 operating modes:

Circulation inside the chamber - air is pumped out of the box, passes through a layer of filters and is forced back into the room. It is used when cleaning the camera before starting painting work;
Supply from the outside - the supply compressor takes air from outside the box, filters it and passes it through the heat generator, where the air is given the required temperature. The flow is fed into the chamber, after which the exhaust compressor pumps the exhaust air out. It is used in the process of painting a car to eliminate paint fog;
Recirculation with heating - the air taken from the chamber is filtered, passed through the heat generator with heating to a predetermined temperature and fed back into the box. It is used to maintain the temperature regime when drying the surface of the body after painting.

Supply and exhaust ventilation requires accurate positioning of the inlet and outlet air ducts, since if the channels are not positioned correctly in the box, "blind zones" are formed in which air does not circulate. Suspended paint particles remain in them - a paint mist, which subsequently settles on the surface of the body, which negatively affects the quality of the final coating.

The calculation of supply and exhaust ventilation consists in determining the volume of air supply that provides the air exchange rate necessary to reduce the concentration of toxic paint fumes (MAC) in the room to the standard level.

Industrial spray booth

The amount of paint evaporation depends on the type of solvent added:

The calculation of supply ventilation according to the air exchange rate is carried out according to the formula K = d*S*H, wherein:

d is the required air exchange rate of the room;
S - box area (m2);
H - box height (m).

The current regulatory documents do not contain standards for the frequency of air exchange in spray booths, however, experts recommend calculating the supply ventilation of the room based on the multiplicity of 5 (with partial painting) and 150 (with full repainting of the body).

An example of calculating air exchange in a spray booth with an area of 4 * 7 m and a height of 4 m using the multiplicity formula (taking into account the maximum value - 100) is as follows:

K \u003d 150 * 28 * 4 \u003d 16800 m 3 / hour;

Paint booth manufacturers allow for 25-30% air supply. Factory chambers of similar sizes have an air exchange of 20-25 thousand m 3 / hour (800 m 3 / hour for each m 2 of the box area).

The calculation of air exchange, which ensures the reduction of MPC to the norm, is carried out according to the formula: , wherein :

W - the amount of harmful fumes from the paint for 1 hour of work (mg / h);
Kv - MPC of vapors in the air inside the box (mg/m3);
Kp - MPC of evaporation in the supply stream (when air is taken from outside the chamber = 0).

Harmful fumes for 1 hour of work are determined by the formula: W = 1*Kv*V, Where:

1 - constant;
Kv - normative MPC of the material (mg/m3 per hour);
V - box volume.

Ventilation is carried out according to the formula: U=d*V, where d is the air exchange rate, V is the volume of the box. The amount of air pumped out and injected into the chamber is always the same.

After determining the air exchange, an aerodynamic calculation of the ventilation system is carried out, during which the required cross-section of the air ducts and the air flow rate are calculated, taking into account the resistance of the filter materials.

Paint Booth Filters

The absence of dust and mechanical particles in the air supplied to the box is a factor that predetermines the suitability of the camera for operation, since the dirt that gets on the car body during the painting process negates all the efforts of the painter.

Depending on the filtering method, boxes are classified into two groups:

Dry spray booths, equipped with roll or panel filters for coarse and fine cleaning;
Spray booth with a water curtain - when supplied, the air flow passes through a water cascade or reservoir with an irrigation system. Water filtration in them replaces the primary coarse filter.

Filters for spray booths according to their functional purpose are classified into:

Coarse cleaning - mounted on the external air duct of the supply ventilation, cleans the flow from large mechanical particles;
Fine cleaning - installed on the ceiling of the box or on the internal supply air duct, cleans the air from dust;
Floor filter for spray booth - installed on the exhaust fan, cleans the pumped air from toxic paint fumes.

Filters for painting chambers are consumables that become contaminated during operation, as a result of which their throughput and cleaning quality are reduced. During maintenance of the box, consumables are replaced, the frequency depends on the filter material:

Cardboard chamber filters are changed every 2 weeks;
Fiberglass - once every 40 days;
Ceiling EU5 standard - every 1000 hours;
Outdoor - every 150 hours.

Do-it-yourself supply and exhaust ventilation

The possibility of extraction is selected separately, depending on the size of the spray booth

The hood in the spray booth is equipped with your own hands upon completion of the installation of the box box. The first stage of installation is the creation of a raised subfloor and the placement of an air intake duct in it, through which air is discharged outside the chamber.

The raised floor is built up by pouring concrete into the formwork, in which grooves are provided for laying air ducts, or formed on an existing ceiling. With this approach, a grating floor 20-40 cm high is welded from reinforcing bars, an air intake is laid inside the grating and connected to an exhaust compressor.

The supply air duct box is placed on the ceiling of the chamber, a compressor is connected to it, coupled with a heat generator or electric heating elements, due to which the flow entering the chamber is heated to the required temperature.

To prevent "blind spots" along the side contours of the chamber, 8 air ducts (2 for each wall) are separated from the supply duct along the perimeter of the walls of the box, providing a horizontal air supply.

Hood safety

Spray booth - a room with a high level of fire danger. For its equipment, the use of exclusively explosion-proof ventilation units is permissible.

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The safe operation of the box is achieved due to the following factors:

The heat exchanger that heats the supply air is equipped with a safety thermostat;
Thermal insulation of the chamber is made of fire-resistant materials - mineral or basalt wool;
The box is completed with an autonomous fire extinguishing system;
Heating heating elements of ventilation are grounded according to
The air ducts are equipped with explosion-proof valves for shutting off the air supply and check valves;
In places of accumulation of fire hazardous paint fumes (particles settle in the lower part of the box), if necessary, additional air intakes are installed.

. organizing the supply of painted products, ─ on dead ends and checkpoints . In individual production, intermittent dead-end spray booths are more often used, and in large-scale production, walk-through spray booths are used.

. spray booths can be open and closed (open and closed type). Closed spray booths provide complete isolation of the work area from the surrounding area. This allows, due to the coordinated operation of supply and exhaust ventilation, to maintain a pressure inside the chamber that is different from atmospheric pressure, thereby preventing uncontrolled emission of pollution. The body of the open spray booth forms a partially enclosed space. The number of open openings depends on the dyeing technology, the location of the workplace (outside the chamber or in the chamber) and the method of loading and unloading the products to be painted.

. features of the filtration system device give reason to distinguish two large classes of spray booths ─ dry spray booths And chambers with hydraulic filter.

Chambers with a water curtain in the regulatory documentation

How important, and often necessary, a spray booth with hydro filters or a spray booth with a water curtain is stated in a number of current regulatory documents.

“The air sucked from the spray booths, floor grating booths, is cleaned from the resulting aerosol of the paintwork material. Cleaning should be carried out, as a rule, by the “wet” method in hydrofilters. This provision contains “Sanitary rules for painting work using manual sprayers. Sanitary and hygienic characteristics of working conditions " .

Decree of the Ministry of Labor of the Russian Federation of May 10, 2001 No. 37 “On approval of the Intersectoral rules for labor protection during painting work” even more categorically. Item 3.52.: "Exhaust air from the premises for work with paintwork materials, local ventilation systems and local exhausts should be cleaned from paintwork aerosols by the "wet" method in hydrofilters."

Not only the sanitary and hygienic aspect is important, but also the requirements of fire safety. "PPBO-109-92. Fire safety rules in railway transport» : “Paint work by spraying paint and varnish materials should be carried out in spray booths made of fireproof materials and equipped with hydraulic filters. Without hydraulic filters or other effective devices for trapping aerosols of combustible paints and varnishes, it is not allowed to operate the system of local suction of painting cabinets, chambers and booths.

Color is very important

Spray booths are a relatively young type of equipment, unlike paints or paintwork materials (LKM), which mankind has been using for more than tens of thousands of years.

At least, this age is the oldest of the rock paintings, for which mineral powders, charcoal, lime, clay, and later animal fats, the secret of the glands of living beings and other biomaterials were used. The chemical industry has added to this arsenal a variety of synthetic paint compounds that have made the world much brighter. Of course, the brightness of the sky, water, minerals and plants remained the same, but the noosphere (or anthroposphere) sparkled with all the colors of the rainbow. It happened more. and because color, being an integral part of design, has become one of the most important tools for promoting many products, incl. industrial products. In addition, a thin layer of paint has become of great economic importance, protecting millions of tons of steel products and structures from corrosion.

The importance of color, and therefore of paint equipment in general and spray booths in particular, can be seen in the automotive industry and the huge car service industry that creates hundreds of thousands of jobs. For them, the quality and cost of painting are one of the main trump cards in the competition, and the functionality of the spray booths largely determines the economic efficiency of production.

Prerequisites for the appearance of spray booths

formed in the second half of the 19th century. In 1887, the method of spraying paint compositions was invented in the USA. (This, by the way, stimulated the appearance of paintwork materials with previously unseen properties, for example, quick-drying ones). Furniture manufacturers were the first to adopt the new technology . But soon, and on a much larger scale, it began to be used in the rapidly gaining momentum of the automotive industry.

The interest in spray painting from many industries has given a strong impetus to the development of enterprises producing such devices. But at the same time, with all certainty, he set before them the task of ensuring acceptable working conditions for the personnel operating them. The answer to these challenges was spray booths, with the help of which it was possible to localize the influence of paint fragments that were not fixed on the surface to be painted - the so-called. "colorful mist" Fogs are usually called aerosols, the dispersed phase of which is represented by liquid droplets. . Of course, the pollution that accompanies the staining process, often very toxic, is not exhausted by fogs, ─ it is enough to recall such a component as solvent vapors.

Already at the beginning of the 20th century, such means as an ordered air circulation system and air-purifying filters were involved in the implementation of a technological concept innovative for that time. No matter how outwardly they look like modern spray booths, captured in photographs of the first half of the 20th century, they have changed a lot. Because as a result of scientific and technological progress, dry and hydrofilters, fans, pumps, equipment for applying coatings and coatings themselves have changed (suffice it to recall powder coatings, for which powder spray booths are used).

The range of tasks solved with the help of spray booths has expanded. As in the beginning of their existence, they help minimize the harmful effects of paints and varnishes on the health of workers , only today against the backdrop of more stringent and detailed requirements of national legislation in the field of labor protection. To this was added another important task, which at the beginning of the 20th century was not yet so acute, ─ reducing the burden on the environment .

And of course, the use of spray booths allows ensure modern quality standards of painting , thanks to supply air filtration systems that remove even the finest dust. And by automating technological processes and improving energy efficiency, it is possible to increase productivity and make the painting process more economical.

Water spray booths successfully cope with these tasks. They are easy to use, since the presence of hydraulic filters simplifies the cleaning of fans, filters, pipelines and air ducts from paint particles. The presence of water improves fire safety, minimizes the possibility of an increased concentration of explosive substances. Water curtains with high efficiency purify the air polluted in the working (painting) area from solid particles of paint and glue, solvent vapors, aerosols and other contaminants.

The principle of operation of any spray booth is to create a directed air flow. Outside air enters the working area. The quality of staining will be the higher, the better it is prepared, ─ with the help of filters it is cleaned of solid inclusions, has the right temperature and humidity. Already in the "used" form, contaminated in the working area as a result of contact with paintwork materials, it is cleaned by exhaust ventilation filters and discharged into the environment.

If part of this work is performed by hydrofilters, such devices are called water spray booths or water curtain booths. “Part of the job” ─ since the presence of hydrofilters does not negate the use of dry filters working with them, usually located in front of the exhaust fan, final fine filters.

Hydrofilters

Since the use of hydraulic filters served as the basis for distinguishing spray booths with a water curtain as a separate class of equipment, they (hydrofilters) deserved the full right to be presented first when considering the construction of such cameras.

The term " hydraulic filter ” in this case means an air filter that purifies the air using water as a filter material. The clause “in this case” is due to the fact that sometimes hydraulic filters are called hydraulic filters, i.e. filters used to purify liquids in hydraulic systems.

The use of air hydraulic filters is not a monopoly of spray booths. They, for example, are installed in ventilation systems for air cooling, protection from sparks, removal of soot, soot, grease, and elimination of odors.

Common to all hydraulic filters ─ purification of polluted air occurs when it interacts with water. Depending on the design, screen (cascade), injector and non-injector hydrofilters are distinguished. They differ in the principle of supplying air-purifying water and, as a result, in the features of operation.

In screen hydraulic filters, water curtains are created using overflow water distribution devices and shields. In nozzle rooms - nozzles are used to form water curtains.

Pumping and non-pumping bubbling-vortex hydrofilters are also used, in which air is cleaned as a result of its active mixing with water. Their name comes from the French barbotage - mixing. The principle of operation is the passage of a gas or vapor (in our case, air) through a layer of liquid (in our case, water).

In the screen hydraulic filter, the air flow containing particles of paintwork materials and solvent vapors is fed to the screen, covered with a continuous layer of water flowing down it, the circulation of which is ensured by the operation of the pump. Colliding with water, large particles lose speed and together with it flow into the bath located under the screen. Contaminants that have overcome this barrier are removed when the air flow passes through the water curtains located behind the screen. Cleaner air helps to make a droplet eliminator capable of "processing" vertical and cross air flows.

Along with the front curtains, side curtains can be installed. More effective ink mist trapping is provided by an active water floor (or active water pan) ─ a grated bathtub, possibly recessed into the concrete floor of the workshop.

In nozzle hydrofilters, water is sprayed using nozzles. As a rule, helical or tangential with a hole diameter of several mm.

Screw nozzles form a more stable flame, but tangential nozzles are easier to manufacture and less likely to clog. The pitch of the nozzles is set depending on the angle of the jet cone (usually 70-75º) and the effective length of the torch.

A shield made of sheet steel or polymer materials installed between the rows of nozzles helps to create a directed air flow, preventing it from entering between the water jets.

The flow rate of water depends on the speed of its flow over inclined shields or a screen, as well as the number of curtains and their cross-sectional area (i.e., the thickness of the water layer, which is usually several mm). The circulation of water is almost closed. Almost ─ because due to losses due to evaporation and removal of especially polluted waters, its supply has to be periodically renewed. Sludge from hydraulic filters of spray booths with a water curtain is accumulated by a special water purification system from paint and varnish waste.

In order to keep the water constantly in motion from foaming, anti-foaming additives are added to it.

Case ─ "classic" and not quite

A mandatory attribute of the spray booth is the body. This is not always a "classic" building with a floor, walls and roof. It can consist of only one front wall. There are tubeless coating technologies used, for example, for painting large-format products. And in many such devices, the air is cleaned with the help of hydrofilters. They may have different designs. For example, tubeless installations with bottom suction, consisting of a hydraulic filter, an exhaust ventilation system and a pumping unit. For painting vertical surfaces, lifting platforms equipped with a hydraulic filter are used, ─ air contaminated with paintwork materials particles is drawn into the gap formed by the painted surface and the wall of the hydraulic filter of such a platform.

The presence of side walls and a roof contributes to the creation of a directed air flow and prevents contamination from spray booths located nearby from entering the working space.

Spray booth housings can be solid or modular. The most common material for their manufacture is sheets (panels) of galvanized or stainless steel with a thickness of 0.8-1.5 mm. There is experience in the use of plastic with an anti-adhesive coating, with a thickness of 10 mm or more. The advantage of this solution is that paint residues adhere less well to camera surfaces and are easier to remove.

The dimensions of the spray booths are determined by the organization of work and the size of the products for which they are intended to be painted. The organization of work is where, ─ inside the chamber or outside it, ─ the workplace is located, whether it is necessary to rotate the products during the dyeing process, whether overhead conveyors with swing amplitude are used for their transportation, etc.

Ventilation system

The ventilation system ensures the required direction of movement and uniformity of the flow of exhaust air to be cleaned - from the working area to the hydraulic filter.

Typically, centrifugal and axial fans of medium and low pressure are used, the parameters of which are determined based on the amount of air that must be removed from the spray booth per unit of time. The fan can be installed on its roof. But at the same time, especially in the case of powerful and “speedy” fans, it is necessary to prevent noise and vibration effects on the camera body.

All or most of the clean air enters the open spray booth through open openings directly from the shop, and the lack of it in the room is made up for by the shop supply ventilation. To increase the amount of air used by the spray booth, an air inlet pipe equipped with a valve that opens when the spray equipment is in operation can be used. This is true for spray booths located in small rooms.

The trends in the development of painting technologies used in mechanical engineering, woodworking, the production of building and other metal structures, ─ wherever spray booths with water curtains are used, ─ are determined by the progressive tightening of requirements for environmental protection and sanitary and hygienic requirements, as the most important segment of labor protection. As well as the need to increase economic efficiency by increasing labor productivity, energy and resource saving, and improving the quality of work.

You can meet them by increasing the efficiency of filters, using new construction materials, energy-saving ventilation and pumping equipment, increasing automation and robotization of technological processes. And this means that spray booths with water curtains will have to change. More in content than in form. However, this is exactly what they have been doing for many decades.

It is not pleasant that cold air penetrates into a warm room, cooling it, because in this case it turns out that the street is heated. Not only does this create uncomfortable conditions, it also significantly affects health and wallet. This problem can be overcome with the help of a thermal curtain, which is a reliable barrier between indoor and outdoor air.

They differ in the source of heat, that is, such equipment can be electric and water. The water thermal curtain wins in terms of economy of use, since the heating element is hot water. However, this type of device, like the other, has excellent advantages, due to which it is becoming more and more popular:

Protecting the building from heat loss.
Protection against cold air, which, thanks to the curtain, cannot enter the room.
Creating a barrier that does not allow exhaust gases, dust and insects to penetrate from the street.
Equalization of the temperature gradient.
Protection from drafts, which has a positive effect on health.
Additional space heating.
Ability to keep the door open.
The ability to keep cool in hot weather.
Profitability, due to both less heat loss and the fact that the energy source is not electricity, but water.

Working principle and installation

The principle of operation is quite simple: a powerful fan creates a high-speed airflow, which forms an “invisible barrier”, thanks to such a system, warm air cannot leave the room, and cold air cannot enter it. The heat source of the water curtain is hot water. It turns out that for the operation of the water type of the device, central heating is needed.

Installing such equipment, of course, is difficult, but it cannot be compared with the fact that during operation the overhead costs are low, and the power is very high. The scope of water curtains mostly extends to industrial buildings that have large open openings. The device is indispensable in restaurants, shops and warehouses, that is, those in those places where the doors open very often due to the large flow of people.

Mounting is usually done above the door. Installation above the opening means that the air curtain is horizontal, and on the side of the opening - vertical. It must be remembered that the vertical curtain must be at least ¾ of the height of the opening to be protected. This is the only difference between this type of device and the horizontal one.

main element

The main element of the design is a radial fan, which is necessary to create the necessary air flow. Such a turbine must be uniform and located along the entire length of the device. It helps create an even flow. The engine is mounted on the side of it.

However, often manufacturers decide to place the engine in the center, and small turbines on its sides. The reason for this arrangement of elements is the complexity of manufacturing a turbine with a length exceeding 800 mm. How effective is this installation method? Of course, such a simplified air curtain will cost less, but there will be a "failure" in the central part of the air flow, which significantly reduces the protective properties. In addition, the heating elements will be blown unevenly, and this leads to their earlier failure.

How is the water curtain controlled?

The air curtain is accompanied by at least two switches, one of which must turn on the fan, and the other must turn on the heating elements. Heating power regulators can also be installed, which have two or three steps. Fans can be two speed. The air curtain may have a thermostat that turns off the device or heating elements when the set temperature is reached.

There is a built-in and wired remote control, it all depends on the chosen model. However, the built-in type is used on curtains that are small in size and are installed for windows and doors. This is due to the fact that the ability to reach the buttons depends on the distance. Accordingly, for water curtains, it is more rational to use remote controls that can be installed in the right place.

Sometimes there is a use of a limit switch, which is convenient in that it turns on the device only when the gate is open. It turns out that the switch starts working when opening doors or gates. Its use is very convenient in warehouses and hangars.

Curtain selection

The following factors influence the choice of an air curtain:

Device length.
Power.
Performance.
Type of instalation.
Control method.

We have already discussed the last two factors, now we will talk about the other three.

Performance. It depends on it the speed of air flow and the height of the installation. For example, take a doorway that is about one meter wide and about two meters high. In this case, the "pumping" of the curtain should be from 700 to 900 cubic meters per hour. With this performance, the air flow rate will be about 8 meters per second at the outlet of the device, and about 2 meters per second at floor level. Of course, the price of such devices is not small, therefore, devices with lower performance are used to protect small openings. Since water curtains are used more for industrial buildings, this factor cannot be saved, otherwise the efficiency will be minimal.
Power is also an important factor, given that the equipment can heat the air in the room, although this factor is not at all necessary. For example, let's take a building of 10 square meters, which is not heated, and the height of the ceilings is about three meters. The power required under such conditions is 1 kW. However, in this case, the building must be capital, that is, the ceiling and walls must have good thermal insulation. You should not choose a device with high power for well-heated places or even a device without a heating function. It is worth mentioning the features of the heating function: the air at the air curtain outlet will never be hot, even if the power is maximum, it will only be warm. There is an explanation for this: the heating elements have a high blowing speed.
Length. It can be from 600 to 2000 millimeters. A very popular length is from 800 to 1000 millimeters, such devices are installed above a standard opening, so they are not suitable for industrial facilities where water curtains are often used. How to correctly calculate the length in this case? It should be the same as the width of the opening or a little more. This is important so that the air flow completely blocks the opening and prevents cold air from entering the room.

All this information will help you choose the right water curtain, as it plays an important role in creating comfortable conditions. The installation of such equipment will indicate that caring for people is an integral part of any organization.

How does a spray water spray with a water curtain work?

The task of any spray booth is to ensure that the air in the spray zone is cleaned from spray mist and solvent vapors.

Water spray booths have several levels of air purification from paint.

Level 1- frontal water curtain - this visible part of the spray booth with a water curtain. A stream of water flows down it in a continuous and continuous stream. It must be uniform and completely cover the entire front area (surface) of the curtain.

Level 2 -internal air purification - perhaps here the main filtration and purification of air from paint waste is carried out. Depending on the design of the spray booth and the manufacturer, there are various systems for internal air purification.

Level 3 - dry filtration - performs final air cleaning from the remaining paint particles and protects the fan blades from paint sticking. Depending on the manufacturer, dry filtration is carried out in Italian spray booths with a water curtain in Russian spray booths - in others, such as China, there is no filtration at all.

Below are the structure diagrams of Italian and Russian spray booths:

1) Scheme of water spray booth ZINCOVELO ZA Italy
2) Video of the work of the spray booth Italy

3) Scheme of a water spray booth made in Russia

4) Video of the operation of the painting chamber Russia (built into a clean room, an overpressure chamber)

The principle of operation of the spray booth with a water curtain is as follows.

When spraying the material, a paint mist is formed. The fan, which is installed on the roof of the spray booth, creates a vacuum and draws polluted air through the opening in the spray booth at the bottom of the front curtain.

Also, particles of paint and dust are deposited on the front front surface, which are captured and carried away in a continuous stream into the bath of the spray booth and settle in the water.

Polluted air, which got into the internal cavity of the spray water chamber with the air flow, is subjected to additional purification. In Italian paint booths there are several water cascades, in Russian paint booths it is filtered by an irrigation system. The air is cleaned from spray waste.

Final cleaning - dry filtration installed in front of the fans ( or )

Water spray booths can be of various modifications: with a floor, with side walls, without a floor and without walls. The choice of model depends on the technology of painting and the product, as well as the requirements for the quality of the coating.

Spray booths carry out the function of extracting and cleaning the air.

When creating a painting area, it is very important to ensure the correct microclimate in the spray zone (the desired temperature regime), as well as the incoming air must be cleaned of dust and dirt, this will allow to achieve excellent conditions for obtaining a high quality coating.