Methodological instructions for performing practical work in the discipline “Operation and adjustment of heating equipment. Boiler installation safety automation

Steam boilers DKVR-2.5; 4; 6.5; 10; 20 with gas-oil furnaces - double-drum, vertical-water-tube, designed to produce saturated or superheated steam used for the technological needs of industrial enterprises, heating, ventilation and hot water supply systems.

Advantages:

The reliable hydraulic and aerodynamic design of the boiler ensures high efficiency - up to 91%;

Low operating and maintenance costs;

The DKVR boiler has a prefabricated design, which allows it to be installed in a boiler room without destroying the walls, and quickly connected to existing systems;

It is possible to transfer the boiler from one type of fuel to another;

A wide range of performance control (from 40 to 150% of the nominal value) allows you to use the boiler with maximum efficiency and significantly save costs on heat and power supply;

Possibility of switching the boiler to hot water mode;

The design of the boiler allows it to be used to order various options instrumentation and automation equipment, including automated burners.

Technical characteristics and equipment of DKVR boilers

* With gas Qcalc.8525 kcal/kg, fuel oil Qcalc.9170 kcal/kg.Note . For completing DKVR-2.5 boilers; 4; 6.5; 10 when burning gas and fuel oil, two-zone vortex gas and oil burners of the GMG type are used. In order to save fuel and improve steam parameters, the boilers are equipped with automated block burners such as Cib Unigas, Weishaupt.

In installations burning gaseous fuels, switching to reserve fuel and working on it is very significant. The most convenient backup fuel from the point of view of the speed of transition to it and back is liquid fuel (fuel oil, shale oil, etc.). At the same time, for most boiler plants, both low and large, the backup is solid fuel, which creates certain difficulties and takes time to switch to it and back to gas.

The longest time for switching to reserve fuel and back to gas is required in units that have furnaces for layer combustion of solid fuel. In these installations, it is usually necessary to switch to solid fuel remove from the grate protective layer refractory bricks or slag, and sometimes remove the burners (for example, when equipping the furnace with hearth burners). In addition, mechanized furnaces for layered combustion of solid fuel and devices for supplying fuel to them are located, as a rule, on the front wall of the boiler (for example, furnaces with pneumomechanical throwers, a mechanical chain grate, with a rustling strip, etc.). When operating on gas, these devices must be protected by covering them with fire-resistant bricks and, therefore, when switching to solid fuel, the protective fire-resistant brick must be removed.

As an example, let us consider the transition to backup solid fuel of the DKVR boiler unit, equipped with vertical slot burners, which are the most convenient in terms of speed of transition. Boiler unit type DKVR-10-13, having a furnace with a pneumo-mechanical thrower, converted to gaseous fuel when installing vertical slot burners designed by Lengiproinzhproekt. To switch to burning solid fuels in in this case it is necessary to perform the work in the sequence indicated below.

After turning off the burner devices, open the doors for manually adding solid fuel and knock out the fire-resistant brick with which they were placed into the combustion chamber. This operation takes about 15-30 minutes. Then, through the opened holes, the fireclay or slag protecting the grate is broken off with a cutter. In this case, it is advisable to break the sintered fireclay or slag into the smallest pieces possible and rake them to the next section. After this, the ease of movement of the drive is tested to tilt the grate bars without using much force to avoid damage to the drive mechanism. Then, using the existing drive, you should pump the front and rear sections of the grate and remove slag or fireclay from the front plate with a paddle. Next, you need to use a rake to separate the stuck fireclay scrap or slag from the rear wall of the furnace and pump and close the grate again, then move the slag or fireclay scrap onto the cleaned section and clean it by pumping the grate in the same way as described. The remaining fireclay waste is evenly raked over both sections, and the sections are cleaned by sequential pumping of the grate. If the fireclay does not fail, it is necessary to break it with strokes of the paddle.

The operation of cleaning the grate takes about one hour and must be performed by two people due to the labor intensity of the work and the high temperature. Simultaneously with cleaning the grate from slag, you should open the front sheet of the air box and fill the burner slots with refractory bricks. The embrasures of pneumomechanical throwers open simultaneously with the removal of fireproof protective bricks from the manual loading doors. The entire operation of preparing the furnace for switching to burning solid fuel can be completed in two to three hours. After preparing the firebox, they begin to heat it with solid fuel. To do this, first of all, the caster is tested by putting it into operation.

It is necessary to melt in the following order:

a) fill the coal box with coal;

b) open the blower doors or air dampers, turn on the smoke exhauster (in the absence or insufficient natural draft), slightly open the guide apparatus of the smoke exhauster or the damper behind the boiler, ventilate the firebox for 10 minutes;

c) turn on the electric motor of the spreaders for a short time and cover the grate with a layer of coal 30 - 40 mm thick. Smooth out the layer with a rake. Place chopped wood on top of the layer and light it (without starting the blower). Instead of firewood, you can use heat from another working boiler;

d) as soon as the firewood burns out, spread the resulting wood coke in an even layer over the grate, close the blower door, turn on the blower fan and give gentle blowing under the grate;

e) open the water to cool the thrower bearings. As the layer on the grate burns and the boiler warms up, gradually increase the supply of fuel and air.

Since the boiler was heated up quite well after operating on gas, the duration of its lighting on solid fuel can be reduced to 3/4 - 1 hour and is determined by the possible combustion rate of the coal. Thus, restoration of normal boiler performance can be achieved with good organization of work in three to four hours. To switch from solid fuel to gaseous fuel, due to the fact that it is necessary to fill the embrasures of pneumo-mechanical throwers with refractory bricks, it is necessary to stop the boiler and cool it for 2 - 3 days. When converting the boiler to gaseous fuel, it is necessary to carry out following works: fill the embrasures of the pneumo-mechanical throwers with refractory bricks, open the slots of the gas burners, cover the grate with a layer of slag 50 mm high, and on top of it throw a layer of broken fireclay bricks 150 mm high (pieces of fireclay bricks should be no more than 100 mm).

It is most quickly possible to switch from gaseous to solid fuel and back in cases where the boiler unit is equipped with a chamber firebox for pulverized combustion of solid fuel. In addition, co-combustion of gaseous and solid fuels is possible. To convert the boiler unit from gas to solid fuel, the following operations are performed:

a) the gates that shut off the mill shafts open completely and the gates that regulate the air supply to the shaft mills open slightly; mills are ventilated for 5-8 minutes;

b) the mine mills and their fuel feeders are put into operation one by one to ensure correct rotation and absence of malfunctions; c) fuel feeders and mine mills are stopped and bunkers are loaded with fuel. One of the mills and the fuel feeder are turned on at minimum speed with a minimum air supply to the shaft mill. In this case, it is necessary to monitor the ammeter indicating the load of the mill electric motor, avoiding its overload. If the mill engine load exceeds the permissible limit, immediately turn off the fuel feeder;

d) as soon as the dust flame ignites, reduce the gas supply to the burner by closing the operating valve. In this case, you should monitor the vacuum in the combustion chamber, maintaining it equal to 2-3 mm water column, and the boiler load according to the steam gauge, not allowing its productivity to increase above the nominal, as well as the steam pressure in the boiler, which should not deviate from specified value by more than 0.5-0.7 am;

e) gradually increase the fuel supply to the mill, correspondingly reducing the gas supply to the burner; At the same time, carefully monitor the stability of the combustion of the dust plume;

f) when the gas pressure in front of the burner reaches the minimum permissible value, close the operating and control valves completely and open the tap on the safety plug. Then stop the air supply to the burner.

All operations for turning on the second mill and turning off the gas burner are performed in the same way as described. When switching to solid fuel, you should carefully monitor the change in the temperature of the superheated steam, maintaining it at a given level by regulating the water supply to the desuperheater.

When switching from pulverized fuel to gaseous fuel, the following operations must be performed:

a) purge gas pipelines and check the quality of purge by burning a selected gas sample;

b) light a portable igniter and insert it into the pilot hole of one of the gas burners. Check the stability of the igniter flame;

c) close the tap on the safety plug. Open the control valve fully, then open the working valve slightly and, by setting the minimum permissible gas pressure in front of the burner, in accordance with the existing instructions, make sure that the gas has ignited. Open and adjust the air supply to the burner. If the gas does not ignite, immediately close the operating and control valves and open the tap on the safety plug. Find out the reason why the burner did not light;

d) burn off fuel from the bunkers. Gradually reduce the productivity of the fuel feeder, while simultaneously increasing the gas supply to the burner;

e) after the fuel has been discharged from the bunkers, stop the coal feeder and purge the mill with air (the end of the mill purge is controlled by loading the electric motor using an ammeter). Then stop the mill by closing the air supply to it and the gate that turns off the shaft. Close the damper that regulates the supply of secondary air to the firebox. The second burner is ignited in the same way, and the corresponding fuel feeder and mill are stopped.

In installations where the backup fuel is fuel oil, the transition to it does not cause difficulties and is carried out in the following sequence for the case of installing combined gas-oil burners: the fuel oil is heated to the required temperature, established by local instructions, depending on the brand of fuel oil. After preparing the fuel oil, the performance of all installed burners, with the exception of those converted to fuel oil, increases to maximum. Then the gas supply to the burner, which is transferred to fuel oil, is stopped by closing the working and control valves; The valve for the spark plug opens completely.

The air supply to the burner stops. A fuel oil pilot torch is inserted into the pilot hole and the fuel oil nozzle is ignited from it. After the flame of the fuel oil nozzle becomes stable, performing similar operations, the next burners are switched to burning fuel oil.

The transition from fuel oil to gas combustion is carried out in the following sequence: gas pipelines are purged, a portable gas igniter is ignited and inserted into the ignition hole, the supply of fuel oil to one of the burners is stopped and it is ignited by gas supply. After the performance of the burners when operating on gas reaches the nominal value, similar operations are performed on the remaining gas-oil burners.

Due to the seasonal operation of many gaseous fuel installations, the issue of conservation is very important gas equipment for a long period when another type of fuel is burned. Preservation of equipment begins after turning off the gas supply system, installing a metal plug at the inlet and freeing all gas pipelines from gas.

The following are subject to conservation: pressure regulators, safety and safety shut-off valves, instrumentation, hydraulic fracturing and intra-shop gas pipeline fittings, burner devices and instrumentation of boiler units that are in operation only when the installation is operating on gaseous fuel. Before preserving the equipment, it is necessary to carry out preventive repairs. For preservation, it is recommended to use a special lubricant consisting of four parts by weight of MVP grade instrument oil (GOST 1805-51) and one part of pure paraffin. The lubricant is prepared as follows. Crushed paraffin is poured into the instrument oil, heated to a temperature of 50-60°C, and stirred until completely dissolved.

Protective lubricant covers: valve, lever system, parts of the control regulator, as well as the internal surfaces of the pressure regulator housing, slam-shut valve (and its parts), safety spring valves (and their parts), gas meters (and their parts), gas blocking valves air" (and their parts). The lubricant is applied in a thin layer in a heated state using a spray gun or hand pump. Lubricant for gas meter gears is poured into the box, and the meter rotors are rotated to uniformly cover all gear teeth.

If the GRU equipment is located directly in the boiler shop, then after preventive repairs and application of lubricant it should be covered with tarpaulin covers. All fittings of the main gas distribution system and intra-shop gas pipelines are disassembled, cleaned and lubricated, and the seals are re-installed. Before preservation, burner devices should be inspected and their outlet embrasures should be covered with fire-resistant bricks from the firebox. All U-tube gauges should be removed, drained of mercury, and washed.

Before releasing gas into a system that has been mothballed, it is necessary to test it for density.

Questions .

ON THE OPERATION OF WATER HEATING BOILERS DKVR 4x13

FOR BOILER ROOM OPERATORS.

1. General provisions
2. Preparing the boiler for lighting.
3. Fire up the boiler.
4. Putting the boiler into operation.
5. Boiler operation.
6. Normal boiler shutdown.
7. Emergency stop of the boiler.
8. Final position.

9. Boiler room gas pipeline diagram.

!!! When reading these instructions, use the attached

“Boiler room gas pipeline diagram.”

See the diagram for the digital designation indicated in ().

1. GENERAL PROVISIONS.

1.1. This instruction provides basic requirements for safety measures during the operation of thermal power plants (hot water boilers and water heaters) with water temperatures not exceeding 115°C (hereinafter referred to as “boilers”).

1.2. A person from among the enterprise’s specialists who have experience in operating thermal power plants, have passed the knowledge test in the prescribed manner and have the appropriate certificate is appointed to be responsible for the good condition and safe operation of thermal power plants.

1.3. If the rules for the safe operation of hot water boilers are violated, the employee may be susceptible to thermal burns, injury electric shock, dynamic shocks during a boiler explosion.

1.4. Persons at least 18 years of age who have passed a medical examination, training in an appropriate program, a knowledge test by a qualification commission and have received a certificate for the right to service boilers are allowed to service hot water boilers.

1.5. Repeated testing of knowledge of boiler house workers is carried out by the qualification commission at least once a year, as a rule, at the beginning heating season, and:

when converting boilers to another type of fuel;

when workers switch to servicing boilers of a different type.

1.6. The permission of workers to independently service boilers must be formalized by order of the enterprise.

1.7. The enterprise must develop and approve by the chief engineer instructions on the operating mode and safe service boilers The instructions must be located at workplaces and given to employees against signature.

1.8. Boiler switching diagrams must be posted at workplaces.

1.9. Workers servicing boiler rooms must be provided with special clothing and safety footwear in accordance with current standards:

cotton suit;

combined mittens;

protective glasses.

leather boots or tarpaulin boots;

respirator.

1.10. The boiler room must have OHP-10 (2 pcs.) and OP-10 fire extinguishers.

Workers servicing boiler rooms must be able to use primary fire extinguishing equipment.

It is prohibited to use fire equipment for purposes other than its intended purpose.

1.11. The presence of persons not related to the operation of boilers and boiler room equipment is prohibited in the boiler room. IN necessary cases outsiders may be allowed into the boiler room only with the permission of the administration and accompanied by its representative.

1.12. Boilers and boiler equipment must be kept in good condition.

It is prohibited to clutter the boiler room or store any materials or objects in it. Passages in the boiler room and exits from it must always be free.

1.13. It is not allowed to place tanks with flammable liquid fuel, as well as stocks of fuels and lubricants in the room where the boiler is installed.

1.14. Supervision of technical condition During operation of boilers, external inspection should be carried out:

every shift by boiler room workers with an entry in the shift log;

daily by the person responsible for safe operation

USER MANUALDE TYPE BOILERS

General provisions

1. The instructions contain general instructions for the operation of steam boilers of the DE type, on the basis of which, in relation to specific conditions, taking into account instrumentation and control equipment, each boiler house develops its own production instructions, approved by the chief engineer of the enterprise.

The production instructions and operational diagram of the boiler room pipelines must be posted at the boiler room operator’s workplace.

2. Installation, maintenance and operation of DE type steam boilers should be carried out in accordance with the Boiler Rules.

3. Instructions for operating the burner, economizer, automation system and boiler auxiliary equipment are contained in the relevant instructions of the manufacturers of this equipment.

4. Installation, maintenance and operation of boiler room pipelines should be carried out in accordance with the Rules for the construction and safe operation of steam and hot water pipelines.

5. The owner of the boiler receives from the manufacturer a Boiler Passport, which is issued to the latter when the boiler is transferred to the new owner.

The passport, in the appropriate section, indicates the number and date of the appointment order, position, surname, name, patronymic of the person responsible for the good condition and safe operation of the boiler, the date of testing his knowledge of the Boiler Rules.

The specified person enters into the Passport information about the replacement and repair of boiler elements operating under pressure, and also signs the results of the inspection.

6. Acceptance into operation of a newly installed boiler must be carried out after its registration with the Gosgortekhnadzor authorities and technical examination on the basis of an act of the State or working commission on acceptance of the boiler for operation.

The boiler is put into operation by written order of the enterprise administration after checking the readiness of the boiler installation equipment for operation and organizing its maintenance.

7. In addition to the boiler passport, it is necessary in the boiler room to have a repair log, a water treatment log, a pressure gauge control log, a replacement log of the operation of boilers and auxiliary equipment.

8. Boiler maintenance can be entrusted to persons at least 18 years of age who have undergone medical training. about certification, training and having a certificate for the right to service boilers in accordance with the requirements of subsection 9.2. Boiler rules.

Inspection and preparation for kindlingDE type boilers

1. Check the water supply in the deaerator, the serviceability of the feed pumps and the presence of the required pressure in the feed line, power supply to the automation panels and actuators;

2. Make sure that the boiler elements and fittings are in normal condition and that there are no foreign objects in the firebox and flues;

3. Check the condition and density of the screen between the firebox and the convective beam;

4. Check the integrity of the protective lining of the drum, the presence and thickness of the asbestos membrane of explosive safety devices;

5. Check the readiness for start-up and operation of the blower fan and smoke exhauster. From the switchboard, test the remote control of the guide vanes, check that they are adjusted correctly for full opening and closing;

6.If the boiler is started after repairs during which the boiler drums were opened, then before closing them, make sure that there is no dirt, rust, scale and foreign objects; check the cleanliness of the pipe connecting the compartments of boilers with a steam capacity of 16 and 25 t/h; check for damage to the steam separation elements and inside the drum devices and for looseness of the joints of the fender panels, guide canopies, and the tightness of their connection to the drum and partition; Before installing new gaskets, thoroughly clean the abutment planes from remnants of old gaskets; When assembling, lubricate the gaskets and bolts with a mixture of graphite powder and oil to prevent burning;

7. Check the correct installation and ease of rotation of the blower pipes. The axes of the nozzles of the blower pipes should be located in the center of the spaces between the boiling pipes;

8. Make sure: the normal condition of the burner parts, burner lance, front wall lining, drums;

9. Check the correct assembly of the burner nozzles.

In the nozzle of the GMP-16 burner, the steam pressure supplied to atomize the fuel affects the angle of the open fuel torch. When the steam pressure for spraying increases during kindling from 0.1 MPa (1 kgf/cm 2 ) to 0.25-0.3 MPa (2.5-3.0 kgf/cm 2 ), a decrease in the spray angle from 65° to 30°, at which coking of the walls of the two-stage fuel combustion chamber does not occur.

Visual control of the initial ignition zone and the exit edge of the embrasure or combustion chamber is carried out through the front hatch of the right side wall.

The temperature of the fuel oil in front of the nozzle should be within 110 -130°C, the viscosity should not exceed 3°VU;

10. After inspecting the firebox and gas ducts, close the manholes and hatches tightly;

11. After checking the serviceability of the fittings, make sure that:

- the boiler purge valves are tightly closed, and if there is a superheater, the purge valve on the superheated steam chamber is open;

- the economizer and boiler drain valves are closed;

- boiler and economizer pressure gauges in operating position, i.e. the pressure gauge tubes are connected by three-way valves to the medium in the drum and economizer;

- direct mode level indicators are included, i.e. steam and water valves (taps) are open and purge valves are closed;

- the main steam shut-off valve and the “steam for auxiliary needs” valve are closed;

- The economizer vents are open.

To release air from the boiler, open the steam sampling valve on the drum and at the sample cooler.

12. Fill the boiler with water at a temperature not lower than +5°C in the following sequence:

After turning on the feed pump (which is done according to the relevant instructions) and supplying water to the economizer, the valve of one of the supply lines opens slightly.

After the appearance of clarified water, the economizer vent closes. The boiler is filled to the lower level in the water indicator glass of the direct-acting level indicator. If the boiler is filled for the first time after repair, it is necessary to flush it, filling it twice with water to the upper level and discharging it through the blowdown and drainage.

The time for filling the boiler with water and its temperature must be indicated in the instructions for kindling.

While filling the boiler, check the tightness of the manhole and hatch valves, flange connections, and the tightness of the fittings (the omission of the latter can be judged by the heating of the pipes after the valves if the boiler is filled with warm water).

If leaks appear in manhole and hatch valves and flange connections, tighten them; if the leak is not eliminated, stop powering the boiler, drain the water and change the gaskets.

After the water in the boiler rises to the lower mark of the level indicator, stop feeding the boiler.

After this, you should check whether the water level in the glass is maintained. If it drops, you need to find out the reason, eliminate it, and then refill the boiler to the lowest level.

If the water level in the boiler rises while the feed valve is closed, which indicates that it is leaking, it is necessary to close the valve upstream.

13. Check the serviceability of the main and emergency lighting by turning it on;

14. Make sure that the boiler instrumentation and control system is working properly, check the fuel cut-off using simulated parameters;

15. Check the serviceability of the gas equipment of the boiler and the ignition protection device. If the boiler is preparing to be fired with fuel oil, run the fuel through the circulation circuit;

16. Supply steam from neighboring boilers to the heating line of the lower drum and heat the water in the boiler to 95-100°C.

Preheating the water will reduce thermal stresses in the metal of the lower drum of the boiler that arise during kindling due to temperature differences between the walls of the upper part, washed by hot combustion products, and the lower part, in contact with relatively cold water.

The DKVR 4-13 steam boiler, the design of which is discussed below, is a vertical water-tube structure with a combustion screen and a boiling unit. The system itself is equipped according to the type of design diagram shown in the main photo. A feature of this configuration is the lateral placement of the convective block of the device relative to the combustion compartment. The device kit includes the unit itself, working platforms and ladders, burners, economizer, fan, smoke exhaust device, water indicator sensors, and fittings.

Device

The steam installation under consideration consists of two main ones - lower and upper drums, as well as a screen-type combustion compartment. The firebox is divided by a brick partition into two chambers ( working part and residual element). This design makes it possible to increase the efficiency of the DKVR 4-13 steam boiler by reducing chemical underburning. Gases from the combustion chamber enter the working compartment at the inlet and outlet in an asymmetrical manner.

In versions with steam superheaters, the last elements are installed in the first flue part on the left side of the boiler. The sides of the upper drum receive cooling from the flow of steam-water composition supplied from the pipes of the front compartment of the convective unit and the side screens.

Additional details

The design of the DKVR 4-13 boiler includes safety valves, the main steam valve, a valve, taps for sampling the mixture and taking it for its own blow-off needs. These elements are located on the upper main surface of the drum.

The feed pipe is located in the water space of the elongated tank, and the separation mechanisms are located in the steam compartment. In the lower main block there is a fitting for draining water and a perforated tube for purging the system. The liquid level is monitored through a pair of indicators. There are two fittings on the front bottom of the upper drum that serve to select pulses of water quantity.

Partitions and pipes

DKVR 4-13 downpipe and steam outlet pipes are connected to the collectors and drum fittings by welding. To prevent sludge from getting into them when feeding the screens, the ends of the elements are brought out into the upper compartment of the drum.

The afterburning system chamber is separated from the beam by a fireclay partition, which rests on a cast iron support mounted on the lower drum. The wall between the first and second flue is assembled using bolts from separate plates. It is first necessary to coat the joints with a special putty or lay an asbestos cord impregnated with liquid glass. The partition has a hole for laying a pipe for a stationary type blowing mechanism. The window for exhaust gases is located on back wall. The heavy-lining DKVR 4-13 boiler is equipped with a lightweight frame. On devices with a design pressure of 1.3 MPa, the superheated steam temperature parameter is not adjusted.

Work sites

These elements are located in places used to service the fittings and fittings of the unit. Among them:

• Side platform for checking water indicating devices.
• Similar service surface shut-off valves and drum safety valves.
• The platform on the back serves for access to the upper drum of the DKVR 4-13 boiler during repairs.

Stairs lead to the sides, and a vertical ladder leads to the rear pedestal.

Other equipment

The DKVR 4-13 unit is equipped with a desuperheater located in the lower drum. It has a drain valve on the steam connecting wires. The amount of incoming mixture is adjusted using a jumper. A special valve is placed between the return and direct elements.

Access to the combustion chamber is provided by a manhole. For screwing fuel near the sidewalls, depending on the configuration of the device, screwing hatches are provided. A pair of such elements are mounted on the side walls at the bottom of the afterburning chamber. There are also windows on the sides of the boilers for cleaning convective pipelines using blowing.

Control and adjustment devices

The condition of the lower part of the insulation of the upper drum in the combustion chamber is monitored through the hatch at the discharge point of the side screen tubes, from the bottom of the flue on the left side of the unit.

In the lower part at the same end of the DKVR 4-13 boiler, the characteristics of which we will consider below, there are manholes installed that serve as windows for regular ash removal, inspection of the working unit and return entrainment ejectors. Through similar hatches the condition of the insulation of the upper drum element is monitored.

Converting the structure to water heating mode makes it possible to increase the productivity of installations and reduce costs for own needs associated with the use of heat exchangers, feed pumps, and continuous blowing devices. In addition, water treatment costs are reduced and fuel is saved.

As shown specifications DKVR 4-13, the average operating efficiency of water heating units increases by 2.5 percent.

Equipment and delivery

The installations under consideration are equipped with fans and smoke exhausters of the VDN and DN types. The package also includes block water treatment devices, filter elements for softening and clarifying water (FOF and FiPA). In addition, the structure is equipped with thermal deaerators, heat exchange units, pumps, and automation kits.

DKVR 4-13 is supplied in bulk, in block parts or in a fully assembled state. The fittings and some individual components are presented separately. This is due to the impossibility of transporting them fully assembled.

Technical characteristics of the boiler DKVR 4-13

The following are the main installation parameters:

Design features

According to the characteristics of the DKVR 4-13 boiler, it uses a single-stage evaporation system. The pipes of the side screens are fixed with one side in the upper drum using the rolling method, and the other ends are welded to the lower chambers.

Longitudinally placed drums are aggregated among themselves through bent boiling elements, forming a developed convective beam. The combustion chamber is divided by a fireclay partition and is located in front of the convection unit. The first row of pipes represents the rear screen of the afterburning compartment. If there are steam superheaters that are installed in the first gas duct after the 2-3rd row of boiling pipes, some elements of the convective beam are not installed.

The working fluid flows simultaneously into the pipes of the side screens, increasing the reliability of the unit and reducing the water level, as well as sludge deposits in the upper drum.

The separation device of DKVR boilers consists of a box with a perforated sheet. It serves as a salinity maintenance device working fluid within 3000 mg/l, if no increased requirements are imposed on the steam.

Exploitation

In the DKVR boiler, the drum manhole gates are located on the rear bottoms. The average liquid level is distributed along the axis of the element. To observe this indicator, there is a pair of pointing devices on the upper drum.

The steam superheating elements located in the first outlet along the gas flow are unified in profile for installations with the same pressure parameter and differ from analogues in the number of parallel coils. Combustion of fuel is ensured by special gas-oil burners (GM).

The presence of remote cyclones in the design requires compliance with certain measures for the arrangement of the unit related to increasing the reliability of equipment operation:

• Each cyclone device must be equipped with a separate power point from one of the drums.
• To ensure constant control over the working fluid standards at the first and second stages of evaporation, it is necessary to install two refrigerators on each boiler. Their purpose is to take samples of feedwater. At the same time, they can serve several boilers.
• In the inner part of the cyclone, a perforated sheet is installed at the top, and a rib is installed at the bottom to prevent the formation of a funnel.
• The installation in question has support frame and the frame is of a welded type, so heavy lining is performed during installation work.

DKVR 4-13: instructions for maintenance, switching on and emergency shutdown

Below are the main excerpts on the operation of the boiler in question.

Turning on the equipment:

1. Before activating the boiler, it is necessary to check the serviceability of the pressure gauge and safety valve (for this, use the forced opening method). They also inspect water-indicating mechanisms, automation, and adjustment devices, and record the results in a special journal.
2. Blow out the lower sections of the boiler.
3. The main procedure for turning on the installation should be carried out after sufficient heating and purging of the steam line. At this stage, you should monitor the serviceability of the main elements, compensators, suspensions and supports. If observed, startup should be stopped until the cause is identified and eliminated.
4. Activation of the boiler is allowed at operating pressure or lower by 0.5 atmospheres.
5. The time of kindling and switching on is entered in the logbook.

Exploitation:

1. Observation of normal operation unit, troubleshooting, calling service teams in case of serious breakdown.
2. Particular attention is paid to the indicators of pressure gauges, the operation of burners and the level of working fluid.
3. On gas installation first add gas and then air (if pressure adjustment is required).
4. All components and parts must be checked according to established deadlines.

Emergency shutdown:

1. The gas and air supply stops and the purge device opens.
2. While observing the water level, close the main steam valve.
3. Make a record of the time and reason for the boiler shutdown and report this to management.
4. In the event of a fire, it is necessary to call the appropriate service and take all measures to localize the source of ignition.

The DKVR boiler stands for a double-drum, vertically water-tube reconstructed unit. Its purpose is to generate steam at a temperature of 194 or 250 degrees. The unit is used in industry, meeting the technological needs of enterprises. DKVR is often used in heating and ventilation systems, as well as for hot water supply.

Features of using boilers

The DKVR steam boiler has a long service life. It can work up to 25 years. Sometimes the unit has been used for more than 50 years. DKVR is not affected natural conditions and temperature changes. Therefore it works equally well in all climatic zones.

The units can be used different types fuel:

• work for liquid fuel and gaseous;
• use coal as fuel;
• work for plant waste(wood, husk) and milled peat.

The fuel used requires an appropriate combustion device. The DKVR boiler, operating using gas and fuel oil, is equipped with stone combustion chambers with gas and oil sprayers. Thanks to this, its productivity can increase by 40%.

To use wood waste as fuel, DKVR boilers must be equipped with special high-speed fireboxes of the Pomerantsev system (TsKTI). For milled peat, units must be manufactured according to the Shershnev scheme with a pre-furnace. Boilers with shaft furnaces are capable of working with coke peat.

To operate on coal, the unit is equipped with semi-mechanical combustion chambers of the PMZ-RPK class.

Unit diagram

Structural diagrams DKVR boilers are usually unchanged. They are not affected by what fuel is used or what combustion device is used.

The volume of the steam unit is named depending on what filler is present in it. So, if a segment contains liquid, then it is a water space. If the sector is filled with steam, then it is called steam. The surface that separates the vapor and water spaces is the evaporation mirror. In the vapor space there is special equipment for separation of steam and moisture.

Unit design

Each DKVR boiler consists of:

• upper long drum;
• lower short drum;
• combustion chamber;
• convective beam;
• supply pipelines;
• partitions;
• blowing device;
• brick wall;
• collector;
• afterburning chambers;
• stairs and platforms for DKVR maintenance.

This is a description of the basic elements of the unit circuit. The drums are placed along the axis of the DKVR boiler and are connected to each other by flared bent circulation pipes. The latter are always located vertically. Thus, a developed convective beam is created.

There are oval holes on the bottoms of the drums. They are necessary for checking and cleaning them or installing additional devices.

The shielded combustion chamber is another component of the DKVR steam boiler. It is divided into two sectors by a brick partition. The first segment is the firebox itself, and the second is the afterburning chamber. The latter increases the efficiency of steam DCWR by reducing chemical underburning.

This device is inherent in boiler models DKVR 2.5; 4 and 6.5. In the DKVR-10 steam boiler, the segments are separated by pipes. At the same time, a brick partition is also present - between the rows of pipes. This separates the boiler beam from the afterburning chamber.

Some circular pipes may not be installed if a superheater is installed in the DKVR boiler. It is placed in the 1st gas duct. It is located immediately behind the 3rd row of circulation pipes. All superheaters are standardized. They differ only in the number of parallel coils. The number of the latter directly depends on the degree of performance of the device.

The DKVR boiler is equipped with end manholes. Through them, sludge deposits are removed.

Additional system elements

In addition to the main components, the unit is equipped with a whole system of measuring devices and additional parts:

• safety valves;
• pressure gauges;
• level indicators and shut-off equipment;
• supply valves;
• purge fittings;
• valves for retaining saturated steam (if there are no superheaters in the DKVR);
• superheated steam selection valves (if there are superheaters in the steam unit);
• fittings in the blowing/warming section of the lower drum (for the DKVR-10 boiler);
• valves for draining liquid from the lower drum;
• valves at the injection section chemical substances;
• valves for steam sampling.

For DKVR-10 units, shut-off and needle valves are provided. They serve for constant purging of the upper drum. Each DKVR boiler has a special staircase and platform. This simplifies its maintenance work.

Description of the operating principle

The operating principle of the DKVR boiler is quite simple. Water first enters the upper drum through two special pipes. Here it is mixed with boiler water. Specific part the latter enters the lower drum through circulation pipes. Then it passes, heating, along the lifting pipes and, together with the steam-water connection, enters the upper drum.

Next part The liquid of the device is directed to the lower collectors through lower pipes. Then the liquid is heated in the screen tubes and the resulting steam and steam-water connection is returned to the upper drum.

Here the steam moves through separation mechanisms. Moisture is separated from it. Dry steam is supplied to the consumer or pumped into the superheater. Here it reaches higher temperatures.

Scheme natural circulation in the boiler, DKVR is ensured due to gravity. Water and steam-water mixture have different densities. Therefore, the liquid always goes down, separating from the steam, which goes up. There may be several circulation circuits.

With proper fluid circulation, the unit is safe. But there are cases when it is violated.

Among possible reasons circulation failure:

• unequal heating of the evaporating surface (usually occurs when individual pipe segments are slagged);
• uneven distribution of liquid through the pipes of screens and collectors (can happen when contaminated with sludge);
• uneven filling of the combustion chamber volume with a combustion torch.

The basic condition for the safe operation of the DKVR boiler is timely cooling of the heating surface. She is constantly affected heat from flue gases. Heat is transferred to the pipes. The task of the coolant, which is located inside the heated pipes, is to circulate evenly, removing this heat from the walls. If the process does not occur intensively, the strength of the metal may be impaired. This threatens fistulas or rupture of pipes.

Advantages

Steam DKVR It has whole line qualities that distinguish it favorably from other similar installations. Its most important property is high performance. The unit produces a significant efficiency indicator even at low pressure levels. Allowed from 0.7 to 1.4 MPa. The productivity of the unit does not decrease due to its fluctuations. At the same time, DKVR boilers do not require specially prepared purified water.

More detailed description advantages of the DKVR boiler:

• if necessary, the unit is switched to water heating mode;
• work on almost any type of fuel;
• the operating diagram of the unit guarantees reliability;
• high efficiency work (up to 91%);
• economical - does not require significant costs for use or maintenance, allows you to reduce the cost of heat and power supply;
• it is possible to install it in the boiler room without destroying the ceilings/walls thanks to the prefabricated structure;
• quick commissioning, quick connection to existing existing systems;
• the design of the unit allows you to change its configuration, using various options for automation elements and instrumentation;
• highly efficient - has a significant range of adjustment of performance parameters (up to 150% of the original value).

Conclusion

DKVR boilers are rightfully considered one of the most productive units. Their design is quite simple, but they are productive and able to work under any conditions. The devices do not require special maintenance. Boilers also do not need special conditions for work.

With his high efficiency steam boilers are economical. They do not require special purification of water, which undergoes a processing process in them. The boilers are quite durable and easy to use. If the work is organized correctly and the rules are followed, their use is safe. DKVR steam devices are also equipped with a number of safety valves.