Repair, flushing of heat exchangers, cleaning, cleaning and maintenance. Regular cleaning of the boiler heat exchangers is a guarantee of its efficient operation Plate heat exchanger cleaning with a solution percentage

During operation, the heat exchange device becomes dirty, scale forms on the walls and plates, sedimentary material settles, which worsens not only the performance of the equipment, but also disables it. In order not to bring to such an extreme, heat exchangers are cleaned of contamination either with their complete disassembly or without disassembly. There are several ways to clean heat exchange equipment, but the most popular is chemical.

Chemical method

This is a set of measures aimed at flushing the heat exchanger with all kinds of chemical reagents that can destroy and rid the system of scale. The choice of reagent is made based on the characteristics and magnitude of contamination.

The implementation of the method is as follows: a reagent is introduced into the heat exchanger with a special device, it circulates inside for several minutes, and then it is removed from there with washing water. Together with the remaining reagent, the PHE must be free of dissolved scale and contaminated water. If one wash cycle is not enough, then the process is started again, and possibly more than once. In addition, more effective reagents are introduced.

The advantage of chemical washing is that the unit does not need to be disassembled, which saves time and money for the event.

In addition to the composition of the cleaning agent, attention should be paid to the temperature of the washing solution, because it also affects the cleaning efficiency. The heating level of the solution is selected taking into account the type and composition of scale.

A poorly performed cleaning operation and the aggressive action of the chemicals used can lead to partial destruction of materials and the formation of cracks in plates and gaskets. And the use of liquid cleaning agents, such as hydrochloric acid, increases the degree of damage and reduces the life of the heat exchanger. Therefore, chemical washing should be carried out using certified reagents, entrusting the work to real professionals!

Hydrodynamic method

The flushing is carried out using a water jet, through which water is supplied under high pressure through a hose into internal system PTO. A variety of nozzles on the hose and varying the power of the water jet allow you to rid the heat exchanger of any contamination, including clogged pipes with zero clearance. Under the influence of powerful hydrodynamic pressure, even stubborn deposits are destroyed.

Electrohydropulse method

PHE cleaning is accompanied by water hammer, which occurs when a high-voltage discharge is applied to the liquid. All this is called the Yutkin effect. A running generator replaces the alternating voltage with a direct one. Output high voltage is fed in parallel to the capacitor through the arrester. Impulse discharge occurs, which provokes the formation of a shock wave in the system. The efficiency of the flushing process is affected by the following:

• water hammer propagates at different speeds in different types of deposits
• most great voltage occurs when a wave passes between the metal surface of the unit and solid deposits on it;
• exfoliated contaminants are washed off with a water hammer and brought out.

Water jet cleaning method

When using this method, a combination of water jet and abrasive cleaning of the PHE occurs. Its advantages:

1. high performance;
2. lack of severe pollution and dust in the workplace.

Currently, heat exchange equipment is used in all spheres of human activity. This is engineering systems buildings (heating, cold supply, hot water supply), technological processes in the production of goods, food, large industrial energy: oil refineries, large plants, thermal power plants, nuclear power plants, and so on.

Tap water cold water in most Russian regions has rigidity, which leads to the appearance of various deposits, scale in the heat exchanger, etc. The internal surfaces of pipelines that have been in operation for ten years are clogged by more than sixty percent. During operation, any unit becomes contaminated, and as a result, heat transfer and the permeability of the coolant / product through the heat exchanger deteriorate. All this leads to loss of heat or violation technological processes which, in turn, leads to high energy costs and loss of quality or quantity of the product produced. At the same time, the cost of cleaning or repairing the unit is an order of magnitude less than the losses that a faulty device can lead to. And even more so the need to replace equipment partially or completely.

The frequency of flushing is determined by the design of the units and their scope (for example, in the food industry, this procedure has to be carried out very often). And the washing method is determined by the design features, the degree and type of pollution. For the equipment to work properly, on average, the device must be flushed once or twice a year. The choice of flushing technology is made by specialists and depends on design features unit and its specifications.

CIP flushing of heat exchangers

In this case, in-place flushing of heat exchangers is considered an effective method. The lamellar, soldered and welded heat exchanger especially needs such washing. Cleaning of the heating plates in this case occurs without disassembling the structure and replacing the seals. Special installations are used here, including a pump and a tank for chemical solutions, as well as a system of filters and hoses. Reagents are selected individually, and they contain inorganic or organic acids, which can clean the device not only from lime, but also from biological organisms. All chemicals are certified by sanitary and epidemiological authorities.

In practice, heat exchangers are often washed with special compounds developed by manufacturers or specialized organizations that quickly dissolve carbonates and iron oxides.

In-place washing and cleaning of the apparatus is carried out in compliance with the safety rules, because there is a danger of personnel getting not only chemical, but also thermal burns. The high temperature of washing chemical solutions is essential for an efficient procedure.

After chemical washing plate heat exchanger completely restores its performance, so in-place flushing replaces the overhaul repair procedure, although it costs several times cheaper.

CIP Method- Inexpensive, fast and simple. Suitable for all types of devices (plate, solder, etc.)

Advantages

• the cost is cheaper, especially on large units;
• less labor-intensive, which reduces the time in some cases, especially on large heat exchangers;
• no need to change seals in plate heat exchangers.

disadvantages

• in some cases does not completely remove deposits, especially mechanical inclusions and scale after installation.

Collapsible flushing of heat exchangers

Attention! Collapsible cleaning of the heat exchanger is available only for plate and shell-and-tube products. Welded and soldered devices cannot be disassembled due to design features. For them, ASGARD-Service specialists will offer various types of cleaning in place.

Collapsible flushing of a contaminated plate heat exchanger is carried out as follows:

• removal of the movable plate, then the package of plates is removed;
• the plates are treated with a special high-pressure apparatus and placed for some time in a special chemical solution that corrodes dirt, but spares the metal;
• the plates are cleaned mechanically - cleaning service engineers remove the stuck dirt that has not succumbed to chemical treatment;
• after processing, the plates are installed in their original place, the device is assembled and undergoes a crimping procedure that guarantees its tightness.

If necessary, pre-reagent treatment of the plates is used. As a rule, if the heat exchanger is less than 8 years old, there is no need to replace the seals. The cost of the seals is typically 4-5 times the cost of the flush itself. During the inspection or during the course of the work, our experts can advise on the remaining life of the seals and the need for replacement.

Collapsible hydrodynamic cleaning of plate heat exchangers:

• the plates are removed from the heat exchanger;
• then they are thoroughly cleaned with a high-pressure water jet;
• mounted back into the unit.

The advantage of the method is its environmental friendliness, while in-place hydrodynamic cleaning is quite effective for many types of pollution.

Collapsible flushing of shell-and-tube heat exchangers is carried out as follows:

• covers/rolls are removed for access to the pipe space.
• using high-pressure apparatuses and special nozzles, each pipe is cleaned separately.
• if it is necessary to clean the annular space, the tube bundle is removed and cleaned from the outside using a high-pressure installation.
• after cleaning by hydromechanical method, all parts of the device are installed in their original place, the heat exchanger is assembled and undergoes a pressure test procedure that guarantees its tightness

The most optimal time for cleaning heat exchangers from scale is the period of scheduled preventive maintenance or emergency repairs of the main equipment. In addition, there are often cases when a major cleaning of the unit is carried out in the process of technical improvement of equipment (increase in power).

Collapsible method

Advantages

• 100% cleaning result of plates/tubes, removal of all insoluble deposits.
• it is possible to inspect the plates/tubes for corrosion and damage.

disadvantages

• the price is usually higher than CIP, especially for large heat exchangers.
• it may be necessary to replace the seals for the plate heat exchangers, which will increase the cost of maintaining the heat exchanger.

Selection of cleaning chemicals for cleaning heat exchangers depending on the type of deposits.

In the process of applying the methods of chemical cleaning of heat exchangers, ASGARD-Service uses certified cleaning agents, they are chemical reagents based on various acids with the addition of surfactants (surfactants), a corrosion inhibitor and complexing agents, diluted with water in the required proportion. The purpose of adding a complex of the above additives is to increase the effectiveness of the reagent on deposits that pollute the internal surfaces of the device, while reducing the corrosive aggressiveness in relation to the metal from which these surfaces are made.

Because acids react to varying degrees with different types deposits, it is recommended to select reagents depending on the type of deposits found on the internal surfaces of the heat exchanger being cleaned.

The data in the table below has been prepared on the basis of information from Alfa Laval regarding the flushing of heat exchangers.

Please note that the following solutions should be used it is forbidden:

• ketones (for example: acetone, methyl ethyl ketone, methyl isobutyl ketone);
• esters (for example: ethyl acetate, butyl acetate);
• halogenated bicarbonates (for example: chlorophene, carbon tetrachloride, freons);
• aromatic compounds (for example: benzene, toluene)

Also, do not use hydrochloric acid cleaners to remove deposits from surfaces and parts of stainless steel structures.

Truly effective cleaning of the heat exchanger significantly increases its performance, and in fact reduces the frequency of cleaning required, keeping the heat exchange equipment in a constantly working condition. The ASGARD-Service company has a proven methodology that leads to impressive results when using any option for cleaning heat exchanger components (plates, tube sheets, channels, casings, ducts and radiator grilles), both hydrodynamic and chemical, or a combination of both.

Our company performs all services related to the restoration of heat exchangers, namely:

• flushing of heat exchangers of all types - plate and shell-and-tube
• repair of heat exchangers of all types:

1. replacement of seals, plates in plate devices, diagnostics of the operation of plate heat exchangers, troubleshooting of plates, pressure testing;
2. replacement of tube bundles in shell-and-tube devices, troubleshooting and pressure testing of the tube bundle;
3. installation / dismantling and replacement of all types of heat exchangers.

The selection of reagents is carried out for each case individually. Ideally, if there are sediment samples, then in practice it is possible to choose the optimal composition and flushing technology (time and temperature regime). Chemical reagents do not affect either the metal or the interlamellar seals.

Our company has a wide range of pumping units, both for washing small plate-type apparatuses of individual heat substations and boiler houses, and for washing large shell-and-tube heat exchangers of large technological enterprises.

In addition, the scientific and technical association conducts research on methods and technologies for reagent cleaning of heat exchange equipment.

The company has its own production base for the creation of high-tech washing equipment for individual needs customer.

In any case, after talking with the Client, our specialists will help you choose the best type of washing, both in terms of quality and prices. Check-out is free.

The need for regular maintenance of heat exchangers, including flushing of internal surfaces.

The most commonly used type of heat exchangers are plate heat exchangers. The most common among them on our market are heat exchangers manufactured by Alfa Laval, Ridan, RoSWEP, Tranter.

At present, plate heat exchangers, having proved their high efficiency in heat supply and hot water supply systems, both industrial enterprises and residential sector facilities, have firmly taken their place in heat points. Now plate heat exchangers are used everywhere, thanks to many obvious advantages.

One of them, experts consider the effect of self flushing heat exchangers, created by high turbulence of the medium flow. In addition, the heat transfer surfaces of the PHE, compared to other types of heat exchange equipment, are much less exposed to contamination by deposits.

However, all of the above does not mean that flushing of plate heat exchangers not required at all. Of course, during operation it is necessary regular cleaning of heat exchange equipment of any type, however, plate heat exchangers can be operated much longer without serious loss of heat transfer between cycles.

Reasons for regular flushing of heat exchangers.

First of all. Untimely flushing of the heat transfer surfaces of heat exchangers leads to the accumulation of contaminants, the formation of hard-to-remove coked deposits on them. The thermal conductivity of which, as a rule, is much lower than that of the thin metal from which the heat exchanger plates are made, thus it becomes much more difficult for heat to pass through the plates contaminated with deposits, as a result of which the heat transfer of the system deteriorates, which leads to an increase in the cost of maintaining the set temperature indicators.

Secondly. Restoring operating parameters in advanced cases will cost much more than regular routine maintenance to flush the heat exchanger.

Thirdly.Prolonged lack of regular may lead to its failure. and even emergencies..

How often should plate heat exchangers be cleaned:

Almost all well-known manufacturers plate heat exchangers, whether Alfa Laval or RoSWEP, etc., are recommended flush the PHE once a year. However, in practice, for enterprises located in Moscow and the Moscow region clean heat exchangers occur one to three times a year.

The need to clean the heat exchanger directly depends on the quality of the feed water and the operating conditions of the system and is determined individually. If the heat exchanger has not been cleaned for a long time and, then collapsible cleaning is usually recommended, in this case it should be Special attention pay attention to the condition of the seals. Average term the service life of the seals is 7 years, so if the seals of the heat exchangers that need to be flushed are older than 7 years, the service will definitely offer to replace them at the same time as flushing the heat exchangers.

The company "InzhSystemService" specializes in the field of flushing heat exchangers.

Due to the fact that by now plate heat exchangers have been widely used, most orders fall on this type of heat exchange equipment.

If operational flushing of heat exchangers is carried out regularly and expertly, the next flushing procedure, as a rule, is performed without dismantling the heat exchanger, by circulating an acid solution of a cleaning agent in the circuit, such a procedure does not take much time and has an optimal cost.

In the case neglecting the flushing procedures for heat exchangers over a long period of time or when hard untreated feed water is used, deposits on internal surfaces can be so significant that they begin to significantly affect the operation of the equipment, leading to a deterioration in heat transfer processes and provoking system failures. Examples of such deposits are shown in the photographs:

• - On the photo #1 and #4 high silty pollution, approx. 1.5 mm;
• - On the photo #2 and #3- compressed hard deposits, when separated, retain the shape of the surfaces of the plates (referred to as "chocolates" or "wafers")

To remove such deposits, it is necessary to apply a much more complex set of measures, including the mandatory disassembly of the heat exchanger, and then, depending on the situation, one of the following procedures can be used:

- Hydrodynamic cleaning of heat exchanger plates by HP;

- Soaking the plates in an acid solution of a cleaning agent, followed by mechanical cleaning of the surfaces of the plates;

A gas heating boiler, as well as any other technological device, functions in sufficient difficult conditions. For this reason, it requires regular maintenance. And one of the most important procedures carried out during maintenance is flushing the gas boiler heat exchanger.

Basic flushing methods

You should start with the fact that the heat exchanger, first of all, is a pipe system with a liquid moving inside. But the water that is used in the systems is usually not of high quality. Various metal salts present in it settle on the walls of the structure, become scale and narrow the passage. There are three ways to deal with scale:

• mechanical;
• chemical;
• by pumping fluid into the system under strong pressure.

The article deals only with do-it-yourself cleaning, and therefore we will not talk about the third method. You definitely cannot cope with it alone, since you will need a special compressor capable of creating a pressure of about 10 atmospheres. Only with the help of this device can deposits on iron surfaces be broken.

Note! With the other two methods, it is quite possible to deal with it yourself. Let's make a reservation right away that this is quite difficult, and appropriate skills will be required.

Video - Cleaning heat exchangers

Method number 1. Mechanical flush

If this flushing of the gas boiler heat exchanger is used, do not forget that the exchanger itself takes up a lot of space in the heat generator. It is located above the combustion chamber, so it is not easy to get there. The algorithm of actions should be as follows.

Step one. The upper body is removed. To do this, it is necessary to turn off the electrical power and gas supply (if all this is provided for by the boiler design).

Step two. The exchanger is disconnected from the heating main.

Step three. The fixtures are removed.

After that, you can remove the heat exchanger from the heat generator and proceed directly to the flushing procedure. And what can be seen after dismantling? As a rule, all internal cavities are clogged with scale - salts of metals, calcium or sodium, as well as trivalent ferum.

For cleaning, you will have to use metal tools - pins, scrapers, and so on. In the course of work, special care should be taken so as not to damage the surface of the structure.

In some cases, the device is wetted in a container filled with a weak solution of hydrochloric acid. And as soon as the scale softens, you can begin to remove it. At the end of the procedure, all internal voids are washed with water under slight pressure. For this purpose, you can attach a hose connected to the water supply system.

You can see for yourself how much dirt will pour out. You need to wait until clean water starts to flow. Additionally, you can tap the surface of the device with a mallet (this is a special hammer made of wood or rubber).

Method number 2. Chemical flush

Immediately make a reservation that such washing is a rather complicated procedure. In the course of work, you will need a special device called a booster. And despite the fact that this option extremely simplified, for its implementation you should still be aware of a number of important nuances.

What is the simplification of the methodology? First of all, there is no need to remove the heat exchanger and dismantle some elements of the gas boiler. It is only necessary to disconnect a pair of pipes (a special hose must be connected to one of them, through which a cleaning agent will be supplied inside the case). After passing through the body, the product will come out through the second pipe, to which a hose will also be connected. Therefore, both in the exchanger and in the booster, the product will move in a circle.

Now let's look at what components the booster itself consists of. These include:

• chemical container;
• an electric heater (not all models have it, but people with experience advise purchasing just such models; this way the reagent will heat up, and being warm, it removes salt and dirt deposits more quickly and efficiently);
• pump.

Note! Such chemical reagents can be various kinds of solutions that are freely available on the domestic market. And the question of choosing the right reagent is the most relevant. In each case, it is necessary to take into account not only the degree of clogging, but also its type, as well as the material used in the manufacture of the heat exchanger.

What is the best way to clean the device?

Now let's figure out what is best to use for flushing. Despite the fact that there are quite a lot of recommendations and instructions, the choice of a particular fluid should be taken with all caution. Most experts advise using saline for this purpose. Such a solution really effectively removes growths, but by its nature it is quite aggressive. Therefore, there may be a risk of destruction of the internal surfaces of the structure.

Note! In addition, there is information that the use of hydrochloric acid can lead to metal brittleness.

And here lemon acid, as it turns out, is not so dangerous for heating equipment. She does great with various types scale - no less effective than today's popular reagents, including Sanaks, Sillit, Detex and others. And if you take care of all elements of the heating system in a timely manner and, more importantly, competently, you can not only increase its performance, but also significantly extend its service life. Cleaning the heat exchanger is one of the most important operations, as we have already found out, will be a significant contribution to this process.

Features of flushing plate heat exchangers

In this case, the exchanger still needs to be disconnected from the boiler and the external and internal surfaces must be cleaned of scale. It's easiest to start cleaning from the outside. First, the device is loaded warm water, to which some household remedy against scale, rust and so on. After some time, the product is washed off the surface with clean water. It is most convenient to carry out this operation on the street, using a car wash for washing, supplying a pressure of water under high pressure. In the absence of such a wash, you can ask the car wash workers to carry out this operation, but do not forget that too much pressure can damage the plates.

After cleaning the outer surface, you can wash the inner walls of the structure (these are the walls of the curved pipe). This flushing of the gas boiler heat exchanger is different in that a fairly thick layer of scale can be on the surfaces, especially if the last cleaning was carried out a long time ago, or was not carried out at all, or if hard water is used in the system. Even dirt can get inside, getting there along with the working fluid, especially in the absence of a cleaning filter.

Video - Cleaning procedure for plate exchangers

Why is it necessary to flush the heat exchanger?

In fact, a heat exchanger is a metal (or made of cast iron) box in which a radiator is installed. This radiator is heated by the fire of a burner located outside and gives off heat to the working fluid circulating inside.

In the case of a clean heat exchanger, it will function with maximum efficiency, and almost all the energy received will be spent on heating. But over time, the walls of the internal channels are covered with various kinds of impurities - salts (scale) dissolved in the liquid. Tellingly, scale is especially actively formed precisely in the secondary exchanger of the boiler for 2 circuits, if hard water circulates in the network.

The consequences of this kind of pollution can be the most unpleasant.

1. The heat exchanger is overheating. According to the operation scheme gas equipment the coolant, which is supplied from the "return" pipeline, must cool the internal surfaces of the heating element. And if scale forms, then the heat exchanger overheats and the device, as a result, fails.
2. The efficiency of the heater is reduced. Mineral deposits, as you know, have a rather low heat conductivity, which is why more energy is spent on heating the liquid. Consequently, fuel consumption increases.
3. Heating equipment fails. Due to mineral deposits on surfaces, the movement of the working fluid is difficult. This forms an excessive load on the circulation pump, which, as a result, quickly exhausts the working resource (in the absence of timely cleaning of narrow passages).

As you can see, if you flush the heat exchanger in a timely manner, you can not only save a lot of money, but also prevent the failure of expensive elements. In addition, a minimum of gas consumption is ensured.

How often should the heat exchanger be cleaned?

When visiting thematic sites, there is very conflicting information regarding how often the heat exchanger should be cleaned, and all other elements of the heater. As a rule, information about the intervals between maintenance is indicated in the manufacturer's instructions for a particular model. But at the same time, it should be remembered that the indicated information is approximate and implies the fact that the operation will be carried out in the most favorable conditions. In fact, flushing the gas boiler heat exchanger is often required more often.

There are indirect signs by which it is possible to determine the degree of clogging of the heat exchanger. It is they who accompany the operation of the heating device.

1. Fuel consumption has increased markedly. According to statistics, in the case of internal scale on the surfaces of the heater, fuel consumption can increase even up to 15 percent.
2. The load on the circulation pump increases, it makes extraneous noise, there are interruptions in operation. All this suggests that flushing is required.
3. The performance of the heating system has dropped. The heating batteries take longer to warm up, the temperature of the working fluid in the return pipe is low, the burner is on all the time. All these signs also clearly indicate that it is time to start flushing.
4. Weak pressure in the tap and "barely alive" liquid in the supply system hot water also say that there are definitely problems in the heat exchanger.

Note! Modern gas boilers are made with the expectation of long-term operation, and spare parts for them are quite expensive. For this reason, cleaning should be started immediately upon detection of the symptoms described above, otherwise the cost of maintaining the device will increase significantly.

Proper operation of the heat exchanger: what to do to make the device last as long as possible?

1. First of all, the feed valve must be located correctly. During repairs, fluid may drain from the system. Often recharge is carried out by means of a special tap. If this happened once, then it's okay, but if this crane is located at the entrance to heater and provided cold water, then as a result, cast iron may experience the so-called "thermal shock" and simply crack. This is due to the fact that cold liquid is supplied to the heated heat generator and the temperature jumps on a local scale, and cast iron, as you know, does not like this.
2. Do not pour antifreeze into the system; in extreme cases, use only a branded product. It costs, by the way, somewhere around 600 rubles per liter. And if the area of ​​\u200b\u200bthe house is, for example, 250 square meters, then about 200 liters of antifreeze will be needed. Of course, if desired, it can be diluted with water, but subject to strict adherence to proportions. For example, to obtain a liquid that will freeze at minus 25 degrees, the proportions are 1:1. Simply put, for the mentioned area you will need about 100 liters (read: 6 thousand rubles). Expensive - of course, but with such a coolant you will be able to protect yourself from possible problems for several years.
3. Fill the system with softened water. As we have already found out, water hardness plays a key role in this matter. If the coolant is hard, then it will contain metal salts that can accumulate on the walls of superheated heat exchangers. This is almost the same as the scale that forms in a kettle.

Summing up a little

So, we found out that flushing the gas boiler heat exchanger (regardless of the method chosen) takes several hours and requires certain skills and knowledge. This can be done with your own hands, or you can entrust it to specialized firms. And you can check how well the cleaning was carried out, both by indirect signs (increased productivity, absence of extraneous noise and overheating), and by means of a video probe inserted into the boiler body after washing. This will allow you to visually verify the quality of the result. The mentioned firms, by the way, provide such a service.

"Warm Company" offers comprehensive maintenance, cleaning and repair of heat exchange equipment in Moscow and St. Petersburg. Our services include the following types of work:

• Flushing of plate heat exchangers(physical, chemical)
• Repair of heat exchangers
• (physical, chemical)
• (physical, chemical)
• Maintenance of heat exchangers
• replacement of seals
• power increase, installation
• supply of spare parts
• consultations

Maintenance of plate heat exchangers: why in Moscow or St. Petersburg is it worth contacting the "Warm Company"?

Our services include washing of plate heat exchangers and their maintenance of the following manufacturers: Alfa Laval, Swep, Gea Ecoflex, G-Mar, Funke, EESTI Termotehnika, MASHIMPEKS, Promenergo, Etra, Thermoblock software .

When cleaning, repairing equipment and pipelines, we use only original spare parts, high-quality equipment (for example, pumps), and specially designed reagents. The service of washing the heat exchanger with acid is in great demand.

By contacting us, you will receive the highest level of service, your equipment will work for a long time and uninterruptedly. This means you save a lot of money!

Cleaning of heat exchangers, flushing of heat exchangers - the choice of method!

Cleaning in place of heat exchangers is selected as the main cleaning method in the following cases:

• when it is necessary to flush the heat exchanger, both brazed and semi-welded;
• when the degree of fouling is assessed as low or medium (method of washing the heat exchangers with acid).

collapsible the most effective and is used in the event that the degree of contamination of the heat exchangers is assessed as severe. This may be due to the fact that the channels are completely clogged with deposits and the heat exchangers need to be cleaned. In such cases, manufacturers advise resorting to a collapsible method that is guaranteed to remove any contamination.

Scheduled preventive maintenance is less painful, significantly extending their lifespan. At the same time, performance improves as well. The main signs of the need for maintenance are: an increase in pressure losses, failure to provide a temperature schedule in relation to the passport values. Conclusion of technical specialists - it is necessary to clean the heat exchanger.

A timely and regular procedure for washing the heat exchanger plates - this is the removal of deposits, scale, dirt, microorganisms of devices of any type significantly extends the service life, which is much cheaper than its overhaul. Nothing is more costly than unscheduled production shutdowns.

However, these costs can be avoided, as much can be planned before the problem becomes a reality. It is only necessary to outline a plan of preventive measures in advance. For example, seals are subject to wear. However, if they are replaced in time, leaks leading to various costs can be avoided. Plates may become dirty. Scale has a negative effect on heat transfer and impairs the quality of work. In some cases, an increased pressure drop can cause serious problems. Timely cleaning and flushing will help to avoid such problems.

Cleaning and flushing of the plate heat exchanger. Service of washing of heat exchangers.

In the process of work, our company uses special chemistry that does not lead to the destruction of the surface of the plates, does not react with seal materials, and at the same time effectively removes almost any type of deposits and scale that form as a result of operation.

Works on the chemical washing of plate heat exchangers, performed by our company, are characterized by high quality, corresponding to international standards, reliability, optimal price-quality ratio.

As part of the service, we clean and wash the heat exchanger plates with chemicals, including acid.

Maintenance and overhaul of heat exchangers

Current repair of the heat exchanger is the prompt elimination of defects in heat exchange equipment. The need for such an event as repair of a heat exchanger may arise in such situations as:

• leakage at one or more places between the plates;
• flow of media from circuit to circuit.

Overhaul of the heat exchanger - is a set of the following activities:

• replacement of all seals after the expiration of their service life (4-6 years);
• complete cleaning of heat exchangers from deposits, scale;
• inspection of the plates for signs of corrosion, rejection of such plates.

Our company provides round-the-clock service for any heat exchangers (emergency service for cleaning and washing the plates in the heat exchanger), as well as an emergency repair service for heat exchangers of any complexity. We also carry out work to maintain the constant performance of your equipment.

You can enter into a service contract or arrange individual visits. The important thing is that you can manage the situation without allowing problems to arise.

We always have the main components and spare parts for the types of heating equipment we service.

As you can see from the photo, timely maintenance is an IMPORTANT condition for stable operation. Seals and some plates have failed

The specialists of the Warm Company clean the plates in an acid bath and wash the plates under pressure.

The cost of flushing heat exchangers, cleaning and repair of plate heat exchangers - Base prices in Moscow and St. Petersburg.

This table shows several types of heat exchangers. You can find out all the prices for the relevant works on the page with prices of our website. The price does not include spare parts. The indicated prices are indicative.

Ridan (Ridan), Sondex (Sondex)

Etra (Etra) Funke (Funke)

Tranter, Swep

Teplotex APV

Mashimpex GEA

Alfa Laval

A heat exchanger is a device through which the heat generated by the coolant is transferred to the environment. Inside the device there are corrugated plates through which the liquid (coolant) passes. Heating equipment, a plate heat exchanger (PHE) (Figure 1), is considered one of the most reliable devices, but with its own drawbacks.

Washing the plate heat exchanger is one of the mandatory procedures that is necessary for the successful operation of the device, to prevent repairs in the future. Due to the fact that the liquid heat carrier has substances in its chemical composition that are capable of settling on the plates, cleaning the device from blockages is necessary. Carrying out the procedure is the key to successful and efficient heat transfer.

PHE and the need for regular cleaning

Since PHE is an efficient and cost-effective heating equipment, it is widely used by modern enterprises. Not a big investment in the operation of the equipment, high efficiency from use is carried out precisely due to the flushing of plate heat exchangers. Other types of heat exchangers require more frequent cleaning than PHEs.

Lack of flushing of plate heat exchangers is fraught with the following consequences:

• Loss of efficiency in the operation of equipment;
• The pollutant changes the thermal conductivity of the plates;
• The likelihood of an accident increases.

The plates are made of thin metals, which allows you to achieve maximum thermal efficiency. Lack of cleaning, in turn, this figure underestimates precipitation, and the lack of cleaning leads to equipment repair work. Not flushing the plate heat exchangers reduces the efficiency of the device, and the cost of maintaining the desired heat increases. Flushing (cleaning) is necessary to remove accumulated dirt that adversely affects the performance of PHE tasks.

Rice. 2

Also, if the device is not cleaned (washed) in time, it will eventually result in an emergency situation, the elimination of which will require financial costs, repairs by specialists. Timely flushing of plate heat exchangers helps to maintain the efficiency of system work at a high level, saves money that will not be spent on repairing plate heat exchangers.

Flushing the heat exchanger and PHE

A heat exchanger of any kind will last a long time, will not require repair if it is flushed (cleaned) in a timely manner. There is a comprehensive range of flushing implementation. Cleaning of contamination that interferes with the normal functioning of the equipment is carried out. Most of the heat exchangers need to be flushed from settling on the walls of the components of the heat carrier.

To prevent repair of plate heat exchangers and most others, regular cleaning is important. It is imperative that the PHE be cleaned once every two or four years, but possibly more frequently. If you do not adhere to such a system, then the repair of plate heat exchangers, and in the future the replacement of the heat exchanger with a new device, will turn out to be a familiar activity. Repair costs will not be cheap, unlike preventive flushing (cleaning).

The most dangerous for the operation of the PHE is scale, which settles on the inside of the heat exchanger. Scale is called deposited hard salts, magnesium hydroxide. Cleaning of aggressive substances occurs by flushing the heat exchanger chemical type. But the scale can also have a more complex composition, which can only be cleaned using a mechanical flushing (cleaning) of the heat exchanger.

Cleaning of plate heat exchangers is possible using:

• Chemical washing;
• mechanical flushing.

The choice of PHE flushing method depends on the following factors:

• type of scale;
• constituent substances in the coolant;
• stages of heat exchanger fouling.

Chemical flush

Cleaning the plate heat exchanger with a chemical flush (fig. 2) is used only in case of low fouling of the PHE. For seriously contaminated equipment, cleaning should only be done mechanically.

Rice. 3

Chemical reagents destroy and remove less aggressive scale from the PHE. When purchasing a flushing agent (cleaning), you need to familiarize yourself with its composition, choose the best option that would correspond to the composition of the coolant.

The equipment is not dismantled before cleaning the plate heat exchanger. This is the difference between dry cleaning and mechanical cleaning, and savings. Special equipment is used to inject chemicals into the PHE unit, as well as dirty water with detached scale.

Stages of dry cleaning:

• Special equipment introduces a chemical solution with active reagents into the PHE. Substances destroy scale.
• Chemicals for some time (according to the instructions of the product) are and circulate inside the PHE. During this time, deposits are destroyed.
• Flushing (cleaning) of the PTO is carried out with clean water. Water, like a chemical agent, circulates inside the equipment for some time. Then the liquid is removed.
• The above three points are repeated until the outlet water is visibly clean.

After cleaning the PHE, it is important to check the equipment. The device must be tested for normal operation:

• Measure the coolant pressure in the PHE;
• Check the possibility of leakage, the integrity of the device.

In order to avoid repair of the PTO, its failure, a check before starting should be mandatory.

Mechanical flush

Mechanical cleaning is also called collapsible (Figure 3). This cleaning method is used less frequently, as it copes with severe pollution, small corrosive deposits, which are rarely allowed by the owners. This method of cleaning takes more time, requires disassembly of the plates, and is less expensive than repair. The plates are washed under strong water pressure. A large amount of deposits that have been formed for a long time can be cleaned due to hydrodynamic flushing (cleaning).

Rice. 4

The main advantage of using cleaning under strong water pressure:

• Environmental friendliness. There is no use of a chemical reagent that pollutes the environment and poisons the air.
• Simple descent of waste water. In the case of dry cleaning, it is necessary to remove water, clean the device from chemical residues several times.

The disadvantage of mechanical cleaning can be attributed not only to the disassembly of the device, but also the use of special equipment to create water pressure. This method is used only for PTO. In the case of brazed heat exchangers (Fig. 4), their flushing (cleaning) is possible only with the help of chemicals. If the amount of deposits is too large, chemicals are powerless, then the brazed plates must be partially replaced. If they cannot be repaired, then a complete replacement is required.

Rice. 5

After cleaning the device, it is important to properly assemble the structure. The next stage of activities after the completion of the flush, as in the case of dry cleaning, is equipment testing. A number of tests will help to establish whether the device is ready for operation, whether it can be repaired, etc. If leaks or other problems are found, then it is necessary to disassemble the device again, and then reassemble it.

Comprehensive cleaning measures

Cleaning a plate heat exchanger using a chemical and mechanical method is quite effective, but sometimes complex cleaning is also required. A large layer of corrosion is removed in a complex way: the device is disassembled, cleaned using chemicals and strong water pressure.

This method is the most expensive, after the failure to clean, only repairs will be required. After disassembling the plates, cleaning is carried out with chemicals, water pressure, cleaning from aggressive reagents and proper assembly of equipment with testing for proper functioning.

To avoid repairs, it is necessary to carry out preventive actions that will help save money and time.

The VekFort company implements the whole range of works on cleaning heat exchangers using high-quality innovative materials and effective methods to combat unwanted deposits. Thanks to their use, our specialists can guarantee high quality cleaning and greater efficiency of the work carried out. Masters of VekFort have extensive experience in project planning and management, especially when the completion date is one of the main criteria.

The main advantages of working with VekFort:

• For achievement optimal result cleaning of heat exchangers, boilers, other heat and heat exchange equipment, hydrochemical and hydrodynamic, hydropower and hydroabrasive cleaning technologies are used, which are currently the most effective.
• During the work, high-quality powerful equipment is used, including hydrodynamic machines with a pressure of up to 1500 bar, installations for cleaning the internal surfaces of pipes using soft abrasive materials, hydraulic impulse equipment for cleaning pipes with diameters from 10 to 100 mm, as well as pumping stations with a capacity of up to 200 m3 / h to ensure the circulation of reagents.
• The company has implemented a quality management system ISO 9001-2008, which guarantees the accuracy of all business processes.
• The company has implemented the environmental management system ISO 14001:2004.
• The company has implemented the occupational safety and health management system OHAS 18001:2007
• For the most effective cleaning by the hydrochemical method, reagents and corrosion inhibitors are used, which have the highest efficiency.
• The company is a design organization and has a SRO permit for the design of works that affect the safety of capital construction facilities; for each type of work, a project for the production of works or technological regulations is developed
• Professional specialists have all the necessary certificates and carry out work strictly according to technological maps.
• The VekFort company is responsible for the structural materials of boiler equipment and excludes their damage.
• The company employs qualified inspectors whose duty is to conduct internal control of the work performed before handing it over to the customer.

Heat exchangers are actively used in the metallurgical, chemical, oil, gas and municipal industries. VekFort offers its customers the following services for all types of industrial heat exchangers:

• cleaning of shell-and-tube heat exchangers;
• cleaning elemental (sectional) heat exchangers;
• cleaning of twisted heat exchangers;
• cleaning of two-pipe heat exchangers;
• cleaning of plate heat exchangers;
• cleaning of finned heat exchangers.

There are several types of standard technologies for cleaning heat exchangers. The choice of a particular one can be influenced by the type of heat exchanger design, the characteristics of the cleaning apparatus and the degree of contamination. The VekFort company offers a variety of methods for cleaning heat exchangers using different technologies including innovative ones. All of them correspond to the Russian categories of standards GOST, SNiP 3. 05. 05-84, as well as ISO standards, international organization for standardization.

Hydrochemical cleaning of heat exchangers

Hydrochemical treatment of heat exchange devices is very effective in combating unwanted deposits, scale. The increase in the number of layers leads to the fact that industrial and utility systems operate at a low level of efficiency. This leads to a decrease in fluid temperature, excessive fuel consumption and an increase in the number of unplanned repairs. Hydrochemical cleaning involves cleaning without preliminary analysis of the structure itself. Cleaning is carried out due to the interaction of chemical reagents circulating in a closed circuit with scale-corrosion deposits on the inner surfaces of plates, pipes and other elements of the heat exchanger.

Clogging of the inner surface of the pipeline of heating systems, which have a service life of more than 10 years, is 60%, and pipes in buildings over 15 years 80%. As a result of deposits, the temperature in the premises decreases, and transportation costs increase.

For hydrochemical cleaning, VekFort uses special installations, which consist of pumps, tanks for preparing the solution, hoses and filters. The pumps used by us allow pumping up to 500 m3/hour. For this washing method, I use reagents based on organic or inorganic acids with the obligatory presence of corrosion inhibitors. They are certified by the Sanitary and Epidemiological Surveillance Russian Federation and do not destroy the integrity of heat exchangers and other equipment. Such chemicals are able to eliminate scale and corrosion, and also destroy all biomass: mold, fungi, algae, microorganisms. Only hydrochemical cleaning of heat exchangers makes it possible to get rid of biological organisms in full.

Hydrochemical cleaning of heat exchange devices will provide:

• restoration of the original throughput; increase in service life of heat exchangers of other equipment by 10-15 years;
• reduction of heat loss during transportation by 20-30%;
• an increase in the temperature of a liquid, vapor or gas to required values without increasing fuel consumption;
• 50% reduction in fuel consumption.

Hydrochemical cleaning is a good alternative overhaul since its cost is several times lower than the replacement of the heat exchange equipment itself. The undoubted advantage of hydrochemical cleaning is the speed of work performed. The entire washing complex is carried out in one cycle.

There are several types of hydrochemical cleaning:

• collapsible hydrochemical cleaning;
• in-place hydrochemical cleaning of plate heat exchangers;
• hydrochemical cleaning of shell-and-tube heat exchangers.

Hydrodynamic cleaning of heat exchangers

The essence of this method of washing the heat exchanger is that the contaminated surfaces are treated with running water under pressure up to 1500 bar. As a result of this, all kinds of deposits and scale are washed off. In most cases, this cleaning method involves the dismantling of heat exchange devices, however, for tubular heat exchange devices, this measure is not necessary. This method involves the use of special installations, which are distributors of a water jet under high pressure. In the presence of significant deposits and dried scale, coarse sand is sometimes used. For greater efficiency, VekFort specialists use nozzles of various modifications that allow you to adjust the required pressure and the angle of its distribution of the jet. They can also use narrow nozzles with large quantity holes that allow you to get inside any device.

Today, this method of cleaning is considered the most effective. It has a number of advantages over others:

• When carrying out hydrodynamic flushing, more than 98% of deposits and scale are removed from the inner surface of the heat exchanger parts, which is quite enough for the normal functioning of the device.
• This method does not damage the surface of the equipment.
• The use of ultra-high pressure systems makes it possible to increase the productivity of the work being carried out, which makes it possible to avoid significant downtime and financial losses.
• The safety and environmental friendliness of the process is due to the fact that it does not use hazardous chemicals.
• This method of cleaning produces a small amount of waste.

The use of hydrodynamic installations allows solving a number of engineering and technical problems:

1. clean heat exchangers, boilers and other equipment,
2. remove all kinds of layers, paint, dried oil products and other deposits,
3. get rid of the inner burr,
4. degrease and decontaminate the internal surface of the heat exchanger.

Causes of deposits on heat exchanger parts

During operation, various deposits accumulate on the parts of heat exchange plants and boilers. They contribute to an increase in hydrodynamic resistance and a decrease in heat transfer. As a result, efficiency is significantly reduced and costs increased. Thus, layers 2-4 mm thick on the inner surfaces of heat-releasing devices reduce the efficiency by 4-7%.

The consequences of the appearance of deposits

In addition to economic losses, the presence of significant deposits on heat exchange surfaces can lead to overheating and rupture metal pipes, i.e. to loss of working capacity. For example, poor water quality, elevated levels of iron, calcium, magnesium salts, organic inclusions cause deposits on the inner surface of parts of heat exchange devices, and reduce their heat transfer and performance characteristics. In addition, the presence of scale accelerates corrosion processes.

Reasons and formula for the economic efficiency of cleaning heat exchangers

In order to calculate the cleaning efficiency of heat exchangers, several parameters must be taken into account. The final result is affected by the performance of the equipment, the amount of fuel used, the number and nature of the deposits present. With such calculations, it is necessary to test the heat exchange equipment, measure the temperature difference on a particular device. The overall economic effect can be calculated independently using the existing formula:

E - economic efficiency in monetary terms (rubles);

P - losses due to lower productivity of heat exchange equipment (rubles);

Z - the cost of cleaning (rubles).

Heat exchange devices of all types: shell-and-tube, sectional, twisted, two-pipe, lamellar, ribbed, need competent cleaning from corrosive deposits and scale. The need to flush heat exchangers appears for several reasons:

• Untimely flushing running water leads to accumulation of deposits.
• Routine cleaning periodic flushing of heat exchangers to prevent breakdowns and scale accumulation.
• Failure of heat exchange equipment due to irregular routine cleaning.

All technologies and materials used to clean heat exchangers and boilers are environmentally friendly for humans and the environment. They do not leave negative consequences after the end of the work. In addition, all equipment for washing heat exchangers used by VekFort specialists complies with safety norms and standards.

Before carrying out any cleaning work on heat exchangers, it is necessary to consult with VekFort specialists. Thus, it is possible to reconcile the disagreements that have arisen, to find best option value for money. In addition, VekFort consultants will make preliminary calculations of the cost of work and develop individual cleaning schemes, taking into account the nature of deposits in heat exchangers.

Examples of cleaning heat exchangers:

Flushing the heat exchanger

CIP chemical cleaning and flushing of heat exchangers

During operation, heat exchanger plates gradually become contaminated, salt deposits, scale, corrosion elements appear on them, fragments of sludge of various origins accumulate between the plates. Such processes lead to a decrease in the resource and performance of heat exchange equipment. That is why plate heat exchangers need regular maintenance and cleaning from scale and dirt. Depending on the type and quality of the media in the heat exchangers and the intensity of their work, it is recommended to carry out chemical cleaning in place at least once every 1-2 years.

When is CIP required for heat exchangers?
There are two types of cleaning of heat exchangers - in-place (chemical) and collapsible. Each method has its advantages and disadvantages and is used depending on the degree of contamination. First of all, the design of the heat exchanger influences the choice of method. Welded or semi-welded heat exchangers can only be cleaned in-place. Collapsible heat exchangers suggest the possibility of both collapsible and CIP cleaning. In this case, the choice of cleaning method depends on the degree of contamination of the plates. Before cleaning the heat exchanger, diagnostics of the equipment are carried out, media analyzes are taken, the actual parameters of the operating equipment are measured and compared with the calculated ones. Based on the results of the diagnostics, a conclusion is issued on the need for service maintenance. If the contamination is recognized as insignificant, the most effective cleaning option is CIP chemical cleaning of heat exchangers.

In the case of significant contamination and a significant pressure drop, it is recommended to carry out a dismountable chemical cleaning of the heat exchangers. In-place flushing with the use of chemical reagents is also carried out for preventive purposes during the heating and non-heating periods.

CIP method:
CIP flushing of the heat exchanger is carried out using a circulation pump unit.

Duringcleaning a special chemical reagent is used that effectively dissolves scale and plaque, as well as organic deposits, protecting the plates and seals. Under pressure, the reagent is fed into the heat exchanger, where it dissolves plaque and flushes out sludge. The final stage of CIP flushing of the heat exchanger - neutralization of the reagent and flushing of the circuits clean water

Benefits of flushing heat exchangers in place
The main advantage of in-place flushing of heat exchangers is the speed of the procedure: disassembly of the equipment is not required; a professional service company takes no more than 4-5 hours to complete the work. Also, this technique is more gentle on seals: since there is no need to dismantle the heat exchanger, seals are not subjected to mechanical stress (especially for equipment with a long service life).

Comparison of in-place and in-place PHE flushes

Our specialists are constantly improving and applying new methods of CIP cleaning of heat exchangers and in some cases very successfully, for example:

The pressure drop across the water was 4 kg/cm3, which indicated a very heavy pollution and the need for collapsible chemical cleaning, but when disassembling the PHE, a set of gaskets of about 255 pieces would have to be replaced, and due to the considerable size of the PHE and a rare brand, the price is comparable to a new PHE of another brand, and the delivery time for such gaskets is 6-8 weeks. Our technicians applied their own PHE flushing method, which is longer (2 working days) and laborious, but the pressure drop was reduced from 4 kg/cm3 to 0.9, of course, this is not always possible, but the fact remains.

Specialists of the MZ Teplo Systems Company will carry out a full range of maintenance and cleaning of the heat exchanger. In our work, we use a special certified reagent that provides a gentle effect on the plates and gaskets of the heat exchanger and at the same time guarantees the effective removal of all contaminants.

Consider an example of flushing a brazed heat exchanger

It can be seen how the ports of the heat exchanger are clogged with scale before flushing and how after flushing

MZ Teplo Systems LLC- performs maintenance and repair of heat exchangers in Moscow and on the territory of the Central Federal District.

List of served regions: Moscow, Moscow, Kaluga, Yaroslavl, Tver, Tula, Ryazan, Tambov, Lipetsk, Tver, Smolensk, Ivanovo, Kursk, Kostroma, Vladimir, Bryansk regions, etc...

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