Steam boilers of the DE series. The design and principle of operation of the boiler. Technical description of boilers type de De 16 technical characteristics

DE boilers are supplied as a block, including upper and lower drums with intra-drum devices, a pipe system of screens and a convective bundle, a support frame, insulation and sheathing.

Technical characteristics of steam boilers DE with gas-oil furnaces

Description of the boiler DE

The combustion chamber of the DE boilers is located on the side of the convective bundle, equipped with vertical pipes expanded in the upper and lower drums. The main components of DE boilers are the upper and lower drums, the convective bundle, the front and side screens that form the combustion chamber.

For boilers with a steam capacity of up to 4 t / h (DE 4 14), the diameter of the upper and lower drums is 700 mm, for the rest - 1000 mm. The distance between the drums is 1700 and 2750 mm, respectively (the maximum possible under the conditions of transportation of the block by rail). For access inside the drums in the front and rear bottoms of each of them there are manhole gates. Drums for DE boilers with a working pressure of 1.4 and 2.4 MPa abs are made from steel 16GS or 09G2S and have a wall thickness of 13 and 22 mm, respectively.

Boilers with a capacity of 4; 6.5 and 10 t/h (DE 4, DE 6 5, DE 10) are made with a single-stage evaporation scheme. Boilers with a capacity of 16 and 25 t/h (DE 16, DE 25) use two-stage evaporation. The rear part of the screens of the furnace and part of the convective beam, located in the zone with a higher gas temperature, are moved to the second stage of evaporation. The circuits of the second evaporation stage have an unheated downcomer system.

The superheater of DE boilers with a capacity of 6.5 and 10 t/h is made of coil pipes. On boilers with a capacity of 16 and 25 t/h, the superheater is vertical, drained from two rows of pipes.

Steel or cast iron economizers are used as tail heating surfaces of DE boilers.

DE boilers are equipped with heating surface cleaning systems.

The fixed supports of the DE boilers are the front supports of the lower drum. The middle and rear supports of the lower drum are movable and have oval holes for bolts, which are attached to the support frame for the period of transportation.

Each DE boiler is equipped with two spring-loaded safety valves, one of which is a control valve. On boilers without a superheater, both valves are installed on the upper drum of the boiler and either of them can be selected as control. On DE boilers with a superheater, the control valve is the outlet manifold valve of the superheater.

The nominal steam capacity and steam parameters corresponding to GOST 3619-82 are provided at a feed water temperature of 100 ° C when burning fuels: natural gas with a specific heat of combustion of 29300-36000 kJ / kg (7000-8600 kcal / m 3) and fuel oil grades M40 and M100 according to GOST 10588-75.

Control range 20-100% of nominal steam capacity. Short-term operation with a load of 110% is allowed. Maintaining the superheat temperature in DE boilers with superheaters is ensured in the load range of 70-100%.

Boilers DE-4-14GM; DE-6.5-14GM; DE-10-14GM; DE-16-14GM; DE-25-14GM can operate in the pressure range of 0.7-1.4 MPa. Boilers DE-10-24GM; DE-16-24GM; DE-25-24GM - in the pressure range of 1.8-2.4 MPa without changing the steam output.

In boiler houses intended for the production of saturated steam without imposing strict requirements on its quality, the steam output of DE type boilers at a pressure reduced to 0.7 MPa can be taken the same as at a pressure of 1.4 MPa.

For DE boilers, the capacity of the safety valves corresponds to the nominal capacity of the boiler at a pressure of at least 0.8 MPa abs.

Feed water and steam quality standards must comply with the requirements regulated by the Rules of the Gosgortekhnadzor of Russia.

The average service life of DE boilers between overhauls with the number of hours of use of the installed capacity of 2500 h / year is 3 years, the average service life before decommissioning is 20 years.

TECHNICAL DESCRIPTION BOILERS TYPE DE

Purpose, technical data and arrangement of DE type boilers

Steam boilers DE are designed to generate saturated or superheated steam used for the technological needs of industrial enterprises, as well as heating, ventilation and hot water supply systems.

The main characteristics and parameters of the boilers are given in Table 1.

Double-drum vertical-water-tube boilers are made according to the design scheme "D", a characteristic feature of which is the lateral location of the combustion chamber relative to the convective part of the boiler.

The main components of the boilers are the upper and lower drums, the convective beam and the left combustion screen (gas-tight partition), the right and rear combustion screens, which form the combustion chamber, as well as the screening pipes of the front wall of the furnace.

In all standard sizes of boilers, the inner diameter of the upper and lower drums is 1000 mm. The length of the cylindrical part of the drums increases with an increase in the steam output of the boilers from 2250 mm for 4 t/h boilers to 7500 mm for 25 t/h boilers. The distance between the axes of the drums is 2750 mm.

The drums are made of sheet steel grade 16GS GOST5520-79 with a thickness of 13 and 22 mm for boilers with a working absolute pressure of 1.4 and 2.4 MPa, respectively (14 and 24 kgf / cm 2).

For access inside the drums in the front and rear bottoms there are manholes.

The convective bundle is formed by vertical pipes Ø51x2.5 mm, located along the entire length of the cylindrical part of the drums, connected to the upper and lower drums.

The width of the convective beam is 1000 mm for boilers with a steam capacity of 10; 25 t/h and 890 mm for other boilers.

The longitudinal pitch of the tubes of the convective bundle is 90 mm, the transverse pitch is 110 mm (except for the average pitch located along the axis of the drums, equal to 120 mm). The pipes of the outer row of the convective bundle are installed with a longitudinal step of 55 mm; at the entrance to the drums, the pipes are bred into two rows of holes.

In convective bundles of boilers 4; 6.5 and 10 t/h longitudinal cast-iron or stepped steel partitions are installed. Boilers 16 and 25 t/h do not have baffles in the bundle.

The convective beam is separated from the combustion chamber by a gas-tight partition (left combustion screen), in the rear part of which there is a window for gases to enter the beam.

The pipes of the gas-tight partition, the right side screen, which also forms under and the ceiling of the combustion chamber, and the pipes for shielding the front wall are inserted directly into the upper and lower drums.

The cross section of the combustion chamber is the same for all boilers. Its average height is 2400 mm, width - 1790 mm. The depth of the combustion chamber increases with an increase in the steam output of the boilers from 1930 mm for DE - 4 t / h to 6960 mm for DE - 25 t / h.

Table 1

To the table

The minimum load of boilers for steam, depending on the state of the burner, is 20-30% of the calculated one.

The maximum load of boilers for steam, taking into account sufficient blast and draft (short-term) for boilers DE-4-10GM-120% of the calculated one; for boilers DE16-25GM-110% of the calculated value.

Feed water temperature - 100°С (+10; -10).

The temperature of the blast air in front of the burner is not lower than 10°С.

The letter “O” in the factory designation of the boilers means: the boiler is sheathed and insulated.

When boilers operating on fuel oil are equipped with a steel economizer, in order to increase the service life of the latter, it is necessary to provide additional feed water heaters that provide water heating in front of the economizer to 130 ° C (to increase the wall temperature of the economizer coils). This is due to the low-temperature, sulfurous corrosion that occurs under these conditions, which proceeds intensively during the condensation of sulfurous acid on colder, below the dew point, metal walls.

The plant can complete the boilers with a steam capacity of 4; 10 t/h compact steel economizers supplied in one unit with the boiler and feed water heaters installed in the bottom drum.

The pipes of the right combustion screen Ø51x2.5 mm are installed with a longitudinal step of 55 mm; at the entrance to the drums, the pipes are bred into two rows of holes.

Shielding of the front wall is made of pipes Ø51x2.5 mm.

The gas-tight baffle is made of pipes Ø51x2.5 mm or Ø51x4 mm, installed with a step of 55 mm. At the entrance to the drums, the pipes are also bred into two rows of holes. The vertical part of the partition is sealed with metal spacers welded between the pipes. Pipe routing sections at the entrance to the drums are sealed with metal plates welded to the pipes and fireclay concrete.

The main part of the pipes of the convective bundle and the right combustion screen, as well as the pipes for screening the front wall of the furnace, are connected to the drums by rolling. To increase the strength of the rolling joints in the walls of the holes drilled under the rolled pipes, one annular recess is knurled. When rolling, the metal of the pipe fills the recess, creating a labyrinth seal.

The pipes of the gas-tight partition are attached to the drums by electric welding or rolling: part of the pipes of the gas-tight partition, the right combustion screen and the outer outfit of the convective bundle, which are installed in the holes located in the welds or the heat-affected zone, are attached to the drum by electric welding or rolled.

The execution of the rear screen of the firebox is possible in two versions:

1. Pipes of the rear screen of the furnace Ø51x2.5 mm, installed with a pitch of 75 mm, are welded to the upper and lower screen headers Ø159x6 mm, which, in turn, are welded to the upper and lower drums.The ends of the rear screen collectors on the side opposite to the drums are connected by an unheated recirculation pipe Ø76x3.5 mm, to protect the recirculation pipes and collectors from thermal radiation, two pipes Ø51x2.5 mm are installed at the end of the combustion chamber, connected to the drums by rolling.

2. C - shaped pipes Ø51x2.5 mm, forming the rear screen of the furnace, are installed with a step of 55 mm and are connected to the drums by rolling.

Superheaters of boilers 4; 6.5 and 10 t/h are made of serpentine pipes Ø32x3 mm.

The single-stage superheater is installed behind the first part of the convective bundle at the turn of the convective flue. Saturated steam from the upper drum is directed by one bypass pipe to the inlet upper manifold of the superheater Ø159x6 mm. Superheated steam exits from the lower collector.

On boilers with a capacity of 16 and 25 t/h for a pressure of 1.4 and 2.4 MPa with a steam superheat of 225°C and 250°C, the superheaters are vertical, from two rows of pipes Ø51x2.5 mm. Pipes of the outer row when entering into collectors Ø159x6 mm are cased up to Ø38 mm. The two-stage superheater is located at the beginning of the convective beam (opposite the exit window from the furnace). The outer row of the superheater, made of cased pipes, simultaneously serves as a part of the enclosing wall of the boiler block. Saturated steam from the upper drum is directed by bypass pipes Ø108x4.5 mm to the upper collector of the first stage of superheating, located second in the direction of gases. Having passed the pipes of the first stage, the lower collector Ø159x6 mm and the pipes of the second stage of superheating, steam is supplied to the outlet collector Ø159x6 mm.

The superheater of the boiler DE-25-24-380 GM is coiled from pipes Ø38x3 mm, two-stage and is located at the beginning of the convective bundle along the entire width of the flue. To regulate superheat, a surface desuperheater is used, located in the lower drum of the boiler, and two control valves.

Saturated steam from the upper drum is directed by bypass pipes Ø108x4.5 mm to the upper collector of the first superheat stage (second in the direction of gases). After passing through the coils and the first stage, steam from the lower outlet of the collector is directed either by two pipes Ø108x4.5 mm to the desuperheater, or by one pipe Ø108x4.5 mm to the lower collector of the second stage of superheating (the first in the direction of gases).

After passing the second stage, the steam is fed through the upper manifold to the outlet. Superheater collectors are made of pipes Ø159x6 mm.

Boilers with steam capacity 4; 6.5 and 10 t/h are made with a single-stage evaporation scheme. In boilers 16; 25 t/h - two-stage evaporation scheme. The second stage of evaporation, with the help of transverse partitions in the drums, includes the rear part of the left and right screens of the furnace, the rear screen and a part of the convective beam located in the zone with a higher gas temperature.

The second stage of evaporation is fed from the first stage through a bypass pipe Ø108 mm passing through the transverse dividing wall of the upper drum. The circuit of the second stage of evaporation has unheated downpipes Ø159x4.5mm.

The lower link of the circulation circuits of boilers 4; 6.5 and 10 t/h, and the first stage of evaporation of boilers 16 and 25 t/h are the least heated rows of tubes of the convective bundle along the gas flow.

AT body of water the upper drum contains a feed pipe and baffle shields, in the steam volume - separation devices.

In the lower drum there is a device for steam heating of water during kindling, a perforated purge pipeline and branch pipes for draining water.

As primary separation devices, baffle shields and guide hoods installed in the upper drum are used, which ensure the supply of the steam-water mixture to the water level. As secondary separation devices, perforated sheet and louvered separator are used.

Baffle shields, guide caps, louvered separators and perforated sheets are made removable to enable complete control and repair of pipe-to-drum rolling joints and the drum itself. All separating devices are attached to the half collars welded to the drum using studs and nuts. Disassembly and assembly of louvered separators and perforated sheets is carried out element by element. Disassembly of the baffle shields begins with the lower shield. Separation devices are assembled in the reverse order.

When assembling steam separation devices, attention should be paid to the creation of density at the points of connection of the fender shields to each other and at the points of their fastening to half-collars, as well as at the points of attachment of the guide visors to the strip with studs: install new paronite gaskets lubricated with graphite.

If it is necessary to adjust the water-chemical regime of the boilers for the introduction of phosphates, a line between the economizer and the boiler should be provided.

On boilers with a steam capacity of 4; 6.5 and 10 t/h, continuous blowing is provided from the lower header of the rear screen (in the case when the rear screen has a header). On boilers with a steam capacity of 4; 6.5 and 10 t/h, in which the rear screen of the furnace is made of C-shaped Ø51 mm, the periodic blowdown of the boilers is combined with the continuous one, carried out from the front bottom of the lower drum: it is recommended to insert the pipeline of the periodic blowdown in the gap between the shut-off and regulating body on the line continuous purge.

Boilers with a steam capacity of 16 and 25 t/h have a continuous blowdown from the second stage of evaporation (salt compartment) of the upper drum and periodic blowdown from the clean and salt compartments of the lower drum and the lower collector of the rear screen (in the case when the rear screen has a collector).

The output of flue gases from boilers with a steam capacity of 4; 6.5 and 10 t/h is carried out through a window located on the rear wall of the boiler. On boilers with a steam capacity of 16 and 25 t/h, the flue gases exit through a window in the left side wall of the boiler at the end (along the gases) of the convective beam.

To clean the outer surface of the pipes of the convective beam from deposits, the boilers are equipped with stationary blowers or a wave generator (GUV).

The blower has a pipe with nozzles that must be rotated during blowing. The outer part of the apparatus is attached to the casing of the left convective wall of the boiler. The blower pipe is rotated manually using a flywheel and a chain.

For blowing, saturated or superheated steam from operating boilers is used at a pressure of at least 0.7 MPa.

The shock wave generator, as well as gas-pulse cleaning (GIP), is a representative of the shock wave cleaning method based on the interaction of contaminated heating surfaces with a shock wave and a high-speed flow of combustion products that are formed during the combustion of a powder charge.

A portable type device weighing 17 kg consists of a shock wave generator itself with a remote trigger, a corresponding barrel and a powder charge.

To carry out activities using this method of cleaning, the boilers are equipped with special nozzles and installation sites (attachments to the casing).

To remove soot deposits from the convective beam, hatches are installed on the left wall of the boiler.

All boilers have three peepers - two on the right side and one on the rear walls of the combustion chamber.

The hole in the furnace can be the opening of the explosive valve or the lance of the burner.

Explosive valves on boilers 4; 6.5; 10 t/h are located at the front of the boiler. Boilers 16 and 25 t/h have three explosion valves - one on the front wall and two on the boiler flue.

The boilers are manufactured at the factory in the form of a single transportable unit, mounted on a support frame and including: drums, piping system, superheater (for boilers with steam superheating), frame, insulation and casing.

Boilers can also be manufactured as a block of insulation and sheathing not installed at the factory: in this case, the insulation and sheathing of the boiler block is carried out at installation in the order described below.

Tight shielding of the side walls (relative pipe pitch S = 1.08), the ceiling and the bottom of the combustion chamber makes it possible to use light insulation 100 mm thick on the boilers, laid on a layer of fireclay concrete 15-20 mm thick, applied over the grid. Asbestos-vermiculite slabs or equivalent ones in terms of thermophysical properties are used as insulation.

The lining of the front wall is made of refractory fireclay bricks of class A or B, diatomaceous bricks, insulating boards, the lining of the back wall is made of refractory fireclay bricks and insulating boards.

To reduce air suction, the insulation is covered from the outside with a metal sheet sheathing 2 mm thick, which is welded to the frame.

Lining and insulating materials are not supplied by the plant.

Technical documentation for the implementation of insulation for design organizations and customers.

Boiler blocks, in the marking of which the last letter is O, are manufactured and supplied by the factory in insulation and sheathing.

As insulation on these boilers, mullite-silica felt MKRV-200 GOST 23619-79 and mineral wool of increased temperature resistance TU36.16.22-31-89 are used, which are placed between the dense enclosing heating surfaces and the boiler casing.

Asbestos cardboard KAON-1-5 GOST 2850-80 and asbestos cord SHAON 22 GOST 1779-83 are used to seal the annular gaps at the entrance to the drums, in explosive valves, burner flanges, manhole covers and other units.

Sheathing sheets of blocks supplied in insulation have a thickness of 3 mm, 2 mm - for boilers supplied without insulation, and are welded along the entire junction contour to the frame elements.

For more information about the insulation (bricking) of boilers, see the sections on installation and repair of boilers.

The support frame takes the load from the elements of the boiler operating under the pressure of boiler water, as well as the framing frame, insulation and casing.

The load from the pressurized elements of the boiler and the boiler water is transferred to the support frame via the bottom drum.

To install the lower drum in the design of the support frame, there are front and rear transverse beams with support pads, as well as supports - two to the right of the drum (from the firebox side) on the transverse beams and two to the left of the drum on the longitudinal beam.

The lower drum at the front of the boiler is fixed by welding the drum to the cross beam of the support frame through the ring and fixed supports. The frame and casing from the front side of the boiler are also fixedly attached to the lower drum. Thermal expansion of the drum is provided towards the rear bottom, for which the rear supports are made movable. A benchmark is installed on the rear bottom of the lower drum to control the thermal expansion of the drum (boiler). The installation of benchmarks to control the thermal expansion of the boilers in the vertical and transverse directions is not required, since the design of the boilers provides thermal displacement in these directions.

For combustion of fuel oil and natural gas, gas-oil burners GMP and GM are installed on the boilers (Table 1).

The main components of the burners are the gas part, the vane apparatus for swirling air, the nozzle assembly with the main and backup steam-mechanical nozzles and flaps used to close the holes of the removed nozzle.

At the front of the burner, a peeper and an ignition-protective device are provided.

The combustion chamber for two-stage fuel combustion, installed on 25 t/h boilers, includes a casing, inner and outer shells, and a tangential air swirler.

The fuel is supplied in full to the GMP-16 burner, installed from the front of the combustion chamber for two-stage fuel combustion. There, through the annular slot formed by the outer casing and the inner shell of the combustion chamber, primary air is supplied (70% of the total air required for complete combustion of the fuel), secondary air (30% of the total) enters through the annular slot and a tangential swirler cameras. The directions of rotation of the primary and secondary air are the same.

The combustion chamber of two-stage fuel combustion is protected from flare radiation by refractory masonry made of fireclay of class "A".

The porthole of the GMP-16 burner is of a conical type with an opening angle of 35° to the side, for the GM-10, GM-7, GM-4.5 and GM-2.5 burners it is of a conical type with an opening angle of 25° to the side.

The GM-7, GM-4.5 and GM-2.5 air burners are vortex, the GM-10 burner is a direct-flow vortex.

Boilers are seismic-resistant under seismic impact with intensity up to 9 points (according to MSK-64 scale) inclusive.

The design of the boilers is constantly being improved, so individual components and parts may differ slightly from those described in

instructions.

FITTINGS, CONTROL AND MEASURING INSTRUMENTS AND SAFETY DEVICESBOILERS TYPE DE

Each boiler is equipped with two spring-loaded safety valves.

On boilers without a superheater, both valves are installed on the upper drum of the boiler.

On boilers with a superheater, one valve is installed on the drum, the second - on the outlet manifold of the superheater.

The valves are adjusted according to the instructions in the relevant section "Installation instructions".

The boilers are provided with two direct-acting water level indicators, which are connected to pipes communicating with the steam volumes of the upper drum.

In boilers with a steam capacity of 16 and 2.5 t/h with a two-stage evaporation scheme, one of the water level indicators is connected to the clean compartment, the second to the salt compartment.

Installation of indicators and their maintenance are carried out in accordance with the accompanying technical documentation of the plant and the Boiler Rules (section 6.3).

The boilers are equipped with the required number of manometers and fittings. ..

The main elements of the boilers are:

1.Upper and lower drums;

3. Left furnace screen - gas-tight;

5. The right furnace screen, the pipes of which are made in the form and cover the ceiling and the lower part of the furnace (underneath);

5.Front screen;

6.Rear screen;

7. Two collectors of the rear combustion screen, made 0 159 * 6 mm;

8.Convective tube bundle;

9.Bricking;

10.Metal frame;

11.Metal sheathing;

12. Headset;

13. Fittings;

14. Control and measuring instruments;

15. Three downpipes, 0 159 * 6 mm for boilers with a steam capacity of up to 16 t / h and 0 219 * 6 mm for boilers DE-25-14;

16. Rear screen recirculation pipe;

17. The blower is located on the left side of the convective beam;

18. Boiler piping.

The drums of the boilers are made of high quality steel grade 16 GS, inner diameter 1000 mm. The wall thickness of the drums is 13 mm. The convective bundle is made along the entire length of the drums from pipes with a diameter of 51ˣ2.5 mm. The left combustion screen is made of pipes Ø 51*4 mm. The right combustion screen, front and rear screens are made of pipes d = 51˟2.5 mm. Two collectors of the rear screen are made of pipes d = 159ˣ6 mm. The recirculation pipe is made of a pipe with a diameter of 76ˣ3.5 mm. Three downcomers - with a diameter of 259ˣ6 mm (boilers DE-25-14).

The length of the cylindrical part of the drums increases from 2250 mm for DE-4-14 boilers to 7500 mm for DE-25-14 boilers. Intercenter distance of drums - 2750 mm. For access inside the drums, there are manholes in the front and rear bottoms of the drums.

The width of the convective beam is 890 mm for boilers 4; 6.5 and 16 tons of steam and 1000 mm for boilers with a steam capacity of 10 and 25 tons of steam per hour.

The pitch of the tubes of the convective bundle along the drums is 90 mm, the transverse pitch is 110 mm. The middle row of pipes of the convective bundle along the axis of the drums has a pitch of -120 mm. The tubes of the outer row of the convective bundle have a longitudinal pitch of -55 mm. At the input to the drums, the pipes are arranged in two rows.

In convective bundles of boilers with a steam capacity of 4; 6.5 and 10 tons of steam per hour to ensure the required flue gas velocities, longitudinal, steel partitions are installed

Boilers with a steam capacity of 16 and 25 tons of steam per hour do not have baffles in the convective beam, and the speed of flue gases is maintained by changing the width of the convective beam (1000 mm).

The convective beam is separated from the combustion chamber by a gas-tight left combustion screen. Gas tightness is ensured by registering metal plates between the pipes along their entire height from the lower drum to the upper drum.

In the rear part of the left combustion screen, metal plates (spacers) do not install the pipes of the rear part of the convective bundle, they are made in the corridor and form “windows” for the entry of flue gases from the furnace into the convective bundle.

The sections of screen pipes wiring at the inlet to the drums are compacted with fireclay concrete.

The pipes of the right combustion screen form the under and ceiling of the furnace.

The pipes of the front screen in the amount of 4 or 2 (various modifications of the boilers) border the burner embrasure on the right and left and are introduced into the upper and lower drums (see the figure).

Boiler DE-25-14 GM (Rear view)

The cross section of the combustion chamber is the same for all boilers. The average height of the combustion chamber is 2400 mm, width 1790 mm. The depth of the combustion chamber increases with an increase in the steam output of the boilers from 1930 mm for boilers DE-4-14 to 6960 mm for boilers of 25 tons of steam per hour.

The main part of the pipes of the convective bundle, the right combustion screen, as well as the pipes of the front screen are connected to the drums by flaring.

The pipes of the gas-tight partition, as well as part of the pipes of the right combustion screen and the outer row of the convective bundle, are welded to the drums by electric welding.

The pipes of the rear screen of the furnace are welded to the lower and upper collectors 0 159 * 6 mm. Collectors, in turn, are welded to the upper and lower drums.

The ends of the collectors on the opposite side of the drums are connected by an unheated recirculation pipe Ø 76 * 3.5 mm.

On all boilers, to protect against overheating from the furnace side of the recirculation pipe and collectors and pipes of the rear screen, two tubes 0 51 * 2.5 mm are installed in the combustion chamber, attached to the drums by flaring (see Fig. No. 2, page 6).

In DE boilers with a steam capacity of up to 10 t / h, four circulation circuits are distinguished:

The water circulation circuit of the convective bundle and the left combustion screen;

Circulating water circuit of the right combustion screen;

Front screen water circuit;

Water circulation circuit of the rear combustion screen.

In boilers DE-16-14 and DE-25-14 having partitions inside the drums and 2-stage evaporation, water circulation is much more difficult.

Boilers with steam capacity 4; 6.5 and 10 tons of steam per hour work with single-stage evaporation. In boilers with a steam capacity of 16 and 25 tons of steam per hour, 2-stage evaporation is used. For these purposes, metal partitions are made in the drums dividing the drums into two compartments: a large compartment - finishing and a small compartment - salt. In the upper drum, the partition is not solid, that is, not for the entire diameter of the drum.

In the lower drum, the partition is solid.

In the second stage of evaporation, with the help of transverse partitions in the drums, there are:

Back of the left and right firebox screens;

Back screen;

Part of a convective stack of pipes located in an area with higher flue gas temperatures.

The second stage of the upper drum is supplied with water through an overflow pipe 0133 mm, at least 2 meters long, passing through the dividing wall of the upper drum.

The circuit of the second stage of evaporation has three downcomer unheated pipes 0159 * 6 mm, for DE boilers with a steam capacity of up to 16 tons of steam per hour and 0 219 * 6 mm for DE-25-14 boilers.

The lowering system of the brine compartment circuit consists of unheated pipes. The downcomer system of the first stage of evaporation consists of the last rows of tubes of the convective bundle in the direction of the gases.

Separation devices are placed in the steam volume of the upper drum: a perforated metal sheet and lamellar separators.

In the water volume of the upper drum there is a feed pipe, a pipe for introducing chemicals. Guide shields and visors for cleaning steam from hardness salts.

In the upper drum of the boiler there are also calming columns and impulse pipes from the finishing and salt compartments to the water level indicators.

Water level indicators are connected to pipes (impulse pipes) coming from the steam and water volumes from the finishing and salt compartments of the upper drum.

DE boilers are produced in the following sizes:

DE 4-14 GM-O
DE 6.5-14 GM-O
DE 10-14 GM-O
DE 16-14 GM-O
DE 25-14 GM-O

May have the letter GM - type of fuel - gas oil
Or GM-O - gas-oil boiler in sheathing and insulation. Steam boilers DE - These are liquid fuel boilers with lateral drums and, as mentioned above, a fully shielded D-shaped furnace. Steam capacity from 4 to 25 tons of steam/hour, pressure 1.4 MPa and superheated steam temperature 194 `C. A complete set with a superheater is possible. The characteristics of the boiler can reach pressure up to 2.4 MPa and temperature up to 380 `C. Coppers of this series have a possibility of transfer to the water-heating mode.
The combustion chamber of DE boilers is located on the side of the convective bundle, equipped with vertical pipes expanded in the upper and lower drums. The main components of the boilers are the upper and lower drums, the convective bundle, the front and side screens that form the combustion chamber.
For boilers of this series, the diameter of the upper and lower drums is 1000 mm. The distance between the drums, respectively, is 2750 mm (the maximum possible under the conditions of transportation of the block by rail). For access inside the drums in the front and rear bottoms of each of them there are manhole gates (manholes). Drums for boilers with a working pressure of 1.4 and 2.4 MPa are made from steel 16GS or 09G2S and have a wall thickness of 14 and 24 mm, respectively.
Boilers with a capacity of 4; 6.5 and 10 t/h are made with a single-stage evaporation scheme. In boilers with a capacity of 16 and 25 t/h, two-stage evaporation is used. The rear part of the screens of the furnace and part of the convective beam, located in the zone with a higher gas temperature, are moved to the second stage of evaporation. The circuits of the second evaporation stage have an unheated downcomer system.
Superheater for boilers with a capacity of 4; 6.5 and 10 t/h is made with a pipe coil. On boilers with a capacity of 16 and 25 t/h, the superheater is vertical, drained from two rows of pipes.
Deciphering the standard size of the boiler. DE 10-14-250 GM-O:

10-capacity-10 tons of steam/hour.
14-pressure-1.4 MPa.
250 - superheated steam temperature -250`C
GM - type of fuel: GM - liquid fuel (gas, fuel oil, etc.), O-boiler in sheathing and insulation.

Steam boilers of the DE series are two-drum, vertical-water-tube devices with natural circulation, a D-shaped combustion chamber and a convective beam placed parallel to the combustion chamber.

Such devices are supplied in one transportable unit (boiler in sheathing and insulation with a supplied burner; a version with an integrated burner is possible), complete with instrumentation, fittings, as well as a headset, stairs, platforms, and a superheater.

Device and advantages of DE boilers

Boilers of the DE series have the following advantages:

• Reliability in operation and increased resource.
• Sufficiently high efficiency - up to 93%.
• Ability to work in the mode of steam generation and water heating.
• The boiler is transportable, supplied on one block, simply installed and connected to utilities.

The equipment of the DE series consists of 2 drums (upper and lower), a pipe system, and additional components. Economizers are used as heating planes.

By agreement with the customer, all boilers are equipped with domestic or foreign burners. DE modifications intended for use with gaseous fuels can be equipped with a heating surface cleaning system.

The combustion chamber is located on the side of the convective beam, equipped with vertical pipes, flared both in the upper and lower drums.

Composition of the furnace block: convective beam, front, side and rear screens. The convective beam is separated from the combustion chamber by a gas-tight partition, in its rear part there is a window designed for the direct entry of gases into the beam.

To ensure the maintenance of gas velocities, longitudinal stepped bulkheads are installed directly in the convective bundles.

So, flue gases, passing completely over the entire cross section of the convective beam, exit through the front wall into a duct located above the combustion chamber, and flow through it to.

Steam gas-oil boilers of the DE series belong to the type of double-drum vertical water-tube devices and are designed for the industrial production of saturated steam, the pressure of which is 1.4 MPa and the temperature is 194°C.

So, DE 25 devices are used to produce steam used for technological work of industrial companies; as heating equipment; in ventilation and hot water systems.

The steam boiler DE 25 14 has the following components: upper and lower drums with a diameter of 1000 mm, a convective beam and a combustion chamber located on the side of the convective part of the device along the convective beam.

At the same time, the distance between the axes of the drums for all standard sizes is the same, and an increase in steam production up to 25 t/h is achieved by increasing the length of the drums, the combustion chamber, and the convective beam.

Equipment DE 10 14 and DE 4 14

Consider what the marking “steam boiler DE 10 14 250GM” means:
10 – power, 10 tons of steam/hour.
14 - pressure, 1.4 MPa.
250 - heated steam temperature, 250 `C
GM - picture of fuel: GM - liquid fuel (gas, fuel oil, etc.).

Such steam plants are delivered as a single transportable unit in a special lining and sheathing. The delivery set includes a gas-oil burner, fittings within the boundaries of the boiler, stairs, platforms.

The steam boiler DE 4 14, whose steam capacity is up to 4 t / h, has a diameter of the upper and lower drums of 700 mm, other types - 1000 mm. The distance between the drums is 1700 and 2750 mm (the maximum allowable for the requirements of the block transportation). For direct access to the inside of the drums, there are manhole locks in the front and rear bottoms.

Characteristics of the steam boiler DE 16 14

The steam boiler DE 16 14 has a two-stage steam generation scheme. The second stage includes the rear part of the chamber screens, as well as the part of the convective beam located in the zone with the highest gas temperature. The circuits of the two-stage steam generation scheme have an unheated system. In devices with a capacity of 16 t/h, the superheater is vertical, drained from two lines of pipes.

Since it is very convenient if the supplier has the opportunity to offer design work, installation and subsequent maintenance of equipment.