Technical operation and repair of DKVr-10-13 boiler plant

Contents

Introduction

1. DKVR boiler 10-13 GM

1.1. Description

1.2. Node-by-Node Diagram with BOM

1.3. Characteristics of main units

1.4. Most likely types of faults and their causes

1.5. Harmful factors that reduce KU operability. Automation of control of this CP

2. Operation of DKVR 10-13 GM boiler

2.1. Commissioning

2.2. Maintenance of CP

2.3. Boiler stop

2.4 Preservation and depreservation of CP

2.5.Scrubbing of CP

3. Repair of DKVR 10-13 GM boiler

3.1. Repair of heating surface elements

3.2. Repair of furnace devices

3.3. Repair of auxiliary mechanisms

3.4. Repair of auxiliary equipment

4. Technical control and regulatory documents

4.1. Periodic inspections and monitoring

4.2. Heat Engineering Tests

4.3. Maintenance and Repair Systems

4.4. Types of repairs

4.5. Repair plans and schedules

4.6. Duration of KP outages related to maintenance and repair

5. Repair and maintenance base

5.1. Organizations performing maintenance of CP

5.2. Equipment of repair enterprises with mechanisms and equipment

5.3. Repair shop departments and their location (on the diagram)

Conclusion

Bibliographic list

Introduction

Operation of gas boiler houses is a type of maintenance involving regular preventive work aimed at diagnosing equipment, timely detection of problems and their prompt elimination. Thus, technical operation services are the key to the uninterrupted provision of heat to residential and industrial facilities in the required amount.

The operation of the boiler unit consists in the following: in melting and stopping the unit, in monitoring and controlling the operation of the boiler unit, choosing the optimal operating modes and the most appropriate distribution of loads, observing the rules of technical and safe operation, in organizing repairs, preventing accidents, etc. The modern boiler unit requires the most careful control and error-free control. The task of monitoring and control is to ensure at every moment the required steam or heat capacity and specified parameters of steam and water with reliable and economical operation of the unit. Performance is the main indicator of boiler plant operation.

Much attention is paid to the proper organization of maintenance and repair of boiler plants, as well as the planning and calculation of heat costs.

Preventive maintenance of boiler plants consists in the introduction of a system of planned preventive repair (PDP) of equipment and constant compliance with the set of organizational and technical measures and the deadlines for their implementation. Scheduled preventive repair includes a set of works carried out as planned (according to schedules) aimed at ensuring emergency-free operation of the boiler house and maintaining gas equipment in working condition. The practice is to carry out the following activities according to a pre-developed and approved schedule.

With automatic control, the combustion processes of individual boilers and the entire technological process of the boiler room as a whole are controlled automatically without the intervention of maintenance personnel and have technical and economic advantages, fuel is significantly saved, since with automatic regulation it is burned more rationally, with smaller losses the number of maintenance personnel is reduced and working conditions of maintenance personnel are improved, heat and productivity of boiler plants increases the service life of boiler equipment and costs for its repair are reduced.

The purpose of the course work is to check the calculation of the boiler unit operating on gas-oil fuel.

DKVR boiler 1013 GM

1.1. Description

The DKVr1013225 boiler of hypermarket two-drum, vertically water pipe productions of the saturated or slaboperegrety steam going on technological needs of the industrial enterprise in heating systems, ventilation and hot water supply are intended for. Fig. 1 (see. annex 1).

Boiler DKVp1013 225GM has a shielded furnace chamber and a developed boiling bundle of bent pipes. To eliminate the tightening of the flame into a bundle and reduce losses with entrainment and chemical flooding, the furnace chamber of the DKVr10 boiler is divided into two parts by a chamotte partition: its own furnace and the burning chamber. On DKVr10 boilers, the combustion chamber is separated from the furnace by pipes of the rear screen. Between the first and the second row of pipes of the boiler bundle of all boilers, a chamotte partition is also installed, separating the bundle from the combustion chamber. Inside the boiler bundle there is a cast-iron partition which divides the bundle into the first and second gas ducts and provides horizontal turning of gases in the bundle during transverse washing of pipes.

The inlet of gases from the furnace to the combustion chamber and the outlet of gases from the boiler are asymmetric.

1.3. Characteristics of main units

If there is a superheater, part of the boiling pipes shall not be installed; superheaters are located in the first gas duct after the second-third rows of boiling pipes. Boilers have two drums - upper (long) and lower (short) - and a pipe system. For inspection of drums and installation of devices in them, as well as for cleaning of pipes with cutters on bottoms there are oval lases with size of 325x400 mm.

Drums of the boiler DKVp1013225 GM, operating pressure 1.4 or 2.4 MPa, are made of steel 16GS, 09G2S, wall 13 or 20 mm thick, respectively. Product quality control is provided due to the providence of ultrasonic diagnostics of drum welds. On the boiler DKVr10 13 GM a passport is issued, the boiler number is assigned. The boiler passport contains all primary documentation for components (drums, pipe system, screen chamber, pipe valves), certificates and permits for use issued by the Federal Service for Environmental, Technological and Nuclear Supervision with the application of SLM acts.

Screen and boiling bundles of DKVp10 13 225 GM boiler are made of steel seamless pipes Ø 51 mm wall 4 mm. For removal of slimes in coppers there are face hatches on the lower cameras of screens, for periodic expulsion of cameras are available the Ø union of 32х3 mm.

DKVr boilers superheaters located in the first gas flow channel are unified in profile for boilers of the same pressures and differ for boilers of different capacities only in the number of parallel coils.

Superheaters - one-way steam - provide the production of superheated steam without the use of steam coolers. The superheated steam chamber is attached to the top drum; one support of this camera becomes motionless, and another - mobile.

Boiler DKVr1013 225 GM has the following circulation scheme: feed water enters the upper drum through two feeding lines, from where it enters the lower drum through poorly heated pipes of the convective bundle. The screens are powered by non-heated pipes from the upper and lower drums. The front screen of the boiler DKVp10 is fed with water from the lower pipes of the upper drum, the rear screen - from the lower pipes of the lower drum. Steam mixture from screens and lifting pipes of bundle enters upper drum. All boilers in the upper drum are equipped with in-drum steam separation devices for steam production.

The DKVr1013225 boiler of hypermarket which delivery can be carried out by one transportable block and in unassembled form have the support frame of a welded design made of rolled steel. Steam boiler DKVp1013 GM does not have a supporting system. The fixed, rigidly attached point of the boiler is the front support of the lower drum. Other supports of lower drum and chambers of side screens are made sliding. Chambers of front and rear screens are attached by brackets to blowing frame. Side screens cameras are attached to the support frame.

The boiler is equipped with control instruments and necessary valves. The following valves are installed on the DKVp1013225 GM steam boiler: safety valves; pressure gauges and three-way cranes to them; level indicator frames with "Klinger" glasses and level indicator shutoff devices; shut-off valves, control and check valves for boiler heating; shut-off valves for blowdown of drums, screen chambers, power supply regulator and superheater; shut-off valves for extraction of saturated steam (for boilers without superheater); shut-off valves for extraction of superheated steam (for

boilers with superheaters); shut-off valves in the line of blowing and heating of the lower drum during melting of boilers (for boilers DKVp10); valves for lowering water from the lower drum; shut-off valves in the chemical injection line; steam sampling valves. Shutoff and needle valves for continuous blowdown of the upper drum are also supplied for boilers of DKVp10 type.

Cast iron headset is installed on the steam boiler DKVp1013 225GM to service the gas ducts.

Numerous tests and long-term experience of operating a large number of DKVr boilers confirmed their reliable operation at reduced pressure compared to nominal pressure. Minimum additional pressure (absolute) in DKVp1013225 GM boiler is 0.7 MPa (7 kgf/cm2). At lower pressure, the moisture of steam produced by boilers increases significantly, and when burning sulfur fuels (Spr > 0.2%), low-temperature corrosion is observed. With a decrease in the operating pressure, the efficiency of the boiler does not decrease, which is confirmed by comparative thermal calculations of cats at nominal and reduced pressures. Boiler elements are designed for operating pressure of 1.4 MPa (14 kgf/cm2), safety of their operation is ensured by safety valves installed on the boiler.

With a decrease in the pressure in the boilers to 0.7 MPa, the configuration of the boilers in the economizers does not change, since in this case the underheating of the water in the feedwater economizers to the saturation temperature of the steam in the boiler is more than 20 ° C, which meets the requirements of the rules of the State Gortekhnadzor.

In the boiler DKVr10 13 225GM, when burning gas and fuel oil, two-zone vortex gas-oil burners of the GMG type are used (2 burners each on the boiler).

Boilers of the DKVr type operating on the mast are equipped with cast-iron economizers, when using only natural gas, steel economizers can be used to assemble boilers.

1.4. Most likely types of faults and their causes

With the conversion to liquid and gaseous fuel, forcing of the boiler operation mode was allowed compared to a nominal capacity of up to 140%. As a result, accidents related to the failure of the pipes of the side screens of the first furnace unit included in the second evaporation stage (salt compartment) and closed to the external centrifugal steam separators (cyclones) became more frequent.

Domestic boiler building developed along the way of adapting boilers to feed water with increased salt content, and remote separators were as impossible to place. Now, in exhaust boilers with salt content of feedwater above 350400 mg/kg, the blowdown exceeds

10%.

The conducted experimental studies of emergency facilities and the accumulated experience of operating hundreds of boilers made it possible to identify the causes of accidents. For the vast majority of cases, they turned out to be typical:

common water supply from the boiler (upper drum);

local discharge of water from the second stage of evaporation at uncontrolled position of water level in remote separators;

increased growth rate of internal deposits in pipes of the second stage of evaporation (salt compartment).

Depending on the cause, the nature of pipe damage is different:

displacement of pipes from the initial position, increase of diameter, rupture of one of them with opening towards the furnace and thinning of walls when water is missed (general or local);

formation of blisters and fistulas with a significant number of deposits under them, especially in case of violation of water regime or blowdown regime.

In 95% of emergency cases, damage to the pipes of the side screens was extended only to the salt compartment. Water leaves it at a faster pace with a general loss of water, the local omission speaks for itself, in it (the salt compartment) there are the greatest heat loads and the highest salt content and the content of scale-forming agents in boiler water. The latter indicates that in gas-oil forced boilers, the salt compartment located in the first unit, near the burners, was out of place.

The prerequisites for general water losses in the first years of operation were the lack of readiness of the maintenance personnel of industrial boiler houses to work with more tense, more mobile and less inertial boilers with a stepped evaporator, unlike other types of boilers DKVr, which also have lightweight frosting and short drums. The skid of water "in the glass" for boilers DKVr2013 was significantly less than in others, but most importantly - unfortunate errors were made in it regarding the connection of water display columns with the lower pulse line, where there was a "water bag," which misled the maintenance personnel with a significant decrease in the water level in the drum (violation of paragraph 6.3.4. "Safe Operation Device Rules...").

The prerequisites for local water losses from the salt compartment were the drawbacks of the design of the ceiling hole sheet in the drum, made of separate elements not welded to each other, and the permissible deviations in the installation of steam removal pipes from cyclones into the drum, which are excessively buried in it, up to the hole sheet. All this disturbed the calculated resistance balance in the communication diagram between the compartments and led to an unacceptable decrease in water levels in the remote separators and, as a result, disruption of water circulation in the salt compartment and damage to the evaporation pipes. The listed design and mounting disadvantages were most likely manifested under increased steam loads and reduced steam pressure in the drum.

It should also be noted that the loose hole sheet in the drum and its joint attachment to the louver packs significantly degrades the separation conditions and results in an increase in the moisture content of the saturated steam.

The prerequisites for burning the pipes of the salt compartment due to the formation of internal deposits were:

permissible deviations from feedwater quality standards, to which forced boilers DKVr2013 turned out to be very "sensitive";

Unsustainable location of the salt compartment;

suboptimal design of short-frame burner devices of the original design of GMG 5/7, which created an extremely uneven distribution of heat loads along the length of the furnace chamber.

All the listed problems with DKVr2013 boilers accidents have long been solved (2025 years ago) and only the lack of adequate information leads to the fact that accidents with them continue to the present.

Operation of DKVR 1013 GM boiler

2.1. Commissioning

The boiler shall be put into operation in accordance with the requirements of the production instruction.

Before starting the boiler, perform the following:

- serviceability check of safety valves, water indication devices, pressure gauges and feed devices;

- check of readings of reduced level indicators by indicators of direct action level;

- check and actuation of safety automation and automatic control equipment;

- boiler blowdown.

Start-up of boilers with faulty valves, feeders, safety automation and emergency protection and alarm equipment is prohibited.

When pressure rises to 0.70.8 MPa (7-8 kgf/cm2) for boilers with operating pressure of 1.3 MPa (13 kgf/cm2) and up to 1.01.2 MPa (1012 kgf/cm2) for boilers with operating pressure of 2.3 MPa (23 kgf/cm2) and 39 MPa (39 kgf/cm2:), warm up the main steam line from the boiler to the collecting collector,

why:

- fully open the drain valve at the end of the steam line of the collecting header and the bypass of the condensate drain;

- slowly open the main steam shutoff valve on the boiler;

- as the steam line warms up, gradually increase the opening of the main steam of the shutoff valve on the boiler; by the end of heating of the main steam line, the steam shutoff valve on the boiler must be fully open.

During heating monitor serviceability of steam line, compensators, supports and suspensions, as well as uniform movement of steam line. In case of vibration or sharp shocks, suspend heating until defects are eliminated.

When the boiler is switched on to the steam line in operation, the pressure in the boiler must be equal to or slightly lower than (not more than 0.05 MPa (0.5 kgf/cm2)) the pressure in the steam line.

As the boiler load increases, the steam superheater blowdown decreases.

2.2. Maintenance of CP

During operation of boilers without superheaters, it is allowed to maintain excess pressure in the boiler not lower than 0.7 MPa (7 kgf/cm2) for boilers with absolute pressure of 1.4 MPa (14 kgf/cm2) and not lower than 1.8 MPa (18 kgf/cm2) for boilers with absolute pressure of 2.4 MPa (24 Krc/CM2) and 4 MPa (40 kgf/cm2) of steam pressure capacity of the valves).

During operation it is necessary to:

- check serviceability of pressure gauges, safety valves, water indication devices and standby feed pumps within the following terms:

- for boilers with operating pressure of 1.3 MPa (13 kgf/cm2) - at least once per shift;

- for boilers with operating pressure of 2.3 MPa (23 kgf/cm2) and 3.9 MPa (39 kgf/cm2) - at least once a day;

- check monthly integrity of asbestos membranes of explosive valves;

- clean and flush the nozzle (when operating with fuel oil);

- eliminate, if possible, leaks of glands, gaskets of valves and water-indicating glasses;

- monitor the serviceability of instrumentation.

Check of alarm serviceability and automatic protection shall be performed in accordance with the schedule and instruction approved by the chief engineer of the enterprise.

The water level in the drum should be maintained as far as possible in the middle of the glass. Do not reduce the level below the lower indicator along the water-indicating glass (90 mm from the horizontal axis of the drum) and increase above the upper indicator (+ 90 mm from the same axis).

The boiler shall be fed evenly. The level of water in the glass should fluctuate slightly.

During operation of the boiler, maintain the specified working steam pressure. The pressure gauge arrow must not go beyond the red line (arrow on the housing) corresponding to the maximum permitted pressure.

For boilers with superheaters, maintain the nominal temperature of superheated steam, preventing its change beyond the deviation specified in the table.

At increase of superheated steam temperature above the nominal one in the boilers at pressure of 39 kgf/cm2, start the steam cooler (with preliminary drain of connecting pipelines), and at the boilers at pressure of 13 kgf/cm2) achieve temperature reduction due to operating measures (reduction of excess air, actuation of nozzles or burners, etc.).

Quality control of saturated and superheated steam is carried out according to the schedule and control procedure developed by the specialized commissioning organization, it is possible to timely detect problems in the separation devices of boilers DKVr1039.

As the pipes of the convective bundle are contaminated, which is manifested by an increase in the temperature of the outgoing gases, an increase in the resistance of the convective part along the gas path and a decrease in productivity, blow the heating surfaces of the boiler, superheater and tail surfaces with steam or air (during repair, washing with alkaline water is allowed).

Perform blowing with stationary blowers at steady load and maximum pressure in the boiler.

The maximum and minimum values of loads at which the boiler and economizer heating surfaces can be blown are determined by the commissioning organization based on the conditions for ensuring the removal of smoke gases from smoke fumes and maintaining stable combustion in the furnace.

Before blowing, warm and blow the section of the steam line to the blower through the drain. After blowing, check the disconnection density and opening the drain of the blowing steam pipelines, since the passage of condensed steam into the gas ducts will cause sulfuric acid corrosion of the heating surfaces.

When burning sulphurous multisole fuel oil, the deposits on the heating surfaces are made more loose and blown when liquid additives VNIINP 102 are added to the fuel oil.

The use of additives can reduce corrosion of heating surfaces. having a wall temperature of less than 100 ^ 150 С.

Boilers with steam production from 2.5 to 10 t/h have a single-stage evaporation scheme. To comply with the "Rostekhnadzor Rules," building codes and boiler water rules and standards established by factory instructions, and safe operation conditions, the following blow-down and drain lines are provided:

- continuous boiler blowdown is carried out from the lower drum into a separate blowdown line connected to the continuous blowdown separator, which allows using the heat of blowdown water in the boiler room diagram, in boilers DKVr1039, DKVr-20, which have two-stage evaporation - from one remote cyclone;

- periodic blowdown of the manifolds of the screens is performed through an independent blowdown pipeline connected by a bubbler (tank without pressure); boilers DKVr1039, DKVr-20 from lower chambers of screens, remote cyclones and lower drum;

- boiler emptying for inspections, repairs, dry preservation at shutdown in reserve is performed from the lower drum of boilers through the elbow to drain water with internal diameter of 50 mm into the free drain line and from the manifolds of screens through the periodic blowdown pipeline (do not perform periodic blowdown of neighboring boilers at this time).

The blowdown mode (periodicity and degree of opening of the control valve for continuous blowdown showers) is established by the commissioning organization according to the initial data of the boiler house design (• water treatment ").

Personnel shall monitor the serviceable condition of all connecting parts of pipelines. valves, gate valves, control valves within the boiler.

Open the valves and gate valves on all pipelines slowly and carefully, close tightly, make the last revolutions of the flywheel quickly.

All actuations, disconnections of pipelines are performed with the knowledge of the supervisor by shift with recording of performed operations in the operation log.

Perform blowdown of water-indicating glasses, pressure gauges, observations through glades in protective glasses.

Perform all switching of valves in hoses.

Periodically perform gas analysis of combustion products (exhaust gases).

An increase in the oxygen content of the exhaust gases against the mode map data determined for the same load and the same conditions indicates an increase in suction in the furnace, gas ducts or economizer.

Prevent boiler operation if there are loopholes in rolling joints (soaring, salt growths). When stopping the boiler for repair and cleaning, carefully inspect the rolling joints of pipes with drums from the side of the furnace in case of detection of salts in the form of fungi, growths, as well as in case of detection of annular cracks in the stretching part of pipes, perform ultrasonic inspection or powder magnetoscopy of rolling places.

Particular attention should be paid to the timely detection of damage to heating surfaces.

When fistula appears, there is intense destruction of connecting pipes.

2.3. Boiler stop

The boiler shall be stopped in all cases except for emergency shutdown only upon receipt of a written order from the administration.

When stopping the boiler, it is necessary to:

- maintain the water level in the boiler above the average operating position;

- stop fuel supply to the furnace;

- blow out water-evidence glasses;

- switch off phosphate injection, stop continuous blowing;

- disconnect the boiler from the steam pipelines after complete cessation of combustion in the furnace and cessation of steam extraction, and if there is a superheater - open the blowdown.

If after the boiler is disconnected from the steam line, the pressure in the boiler increases, the steam superheater boiler blowdown should be increased, it is also allowed to blow the boiler and fill it with water.

When stopping a solid fuel boiler:

- partially covering the thrust and blast vanes, burn the remaining fuel on the grille. Do not fill the burning fuel with fresh fuel or fill it with water.

- turn on the fan and close the gate behind the boiler;

- clean the furnace and bunkers;

- switch off the smoke pump, close the smoke gate, combustion and blast doors (during mechanical furnace completely stop the thrust after grid cooling).

When the gas boiler stops, stop gas supply and then air supply; after disconnection of all burners, the boiler gas pipeline must be disconnected from the common main, the blowdown plug on the branch is open, and the furnace, gas ducts and air ducts are ventilated.

After the fuel supply stops: blow the water display glasses;

- switch off phosphate injection, stop continuous blowing;

- disconnecting the boiler from the main steam line and auxiliary main, it is necessary to feed it to the highest level along the glass, and then stop the water supply to it. In the future, as the level drops, periodically feed the boiler. The water level in the drum shall be monitored all the time while the boiler is pressurized.

Cooling of the boiler is slow due to natural cooling: doors, gliding, eyes keep closed. If the boiler stops for repair after 3-4 hours, you can open the doors and vents of the gas ducts and the gate behind the boiler.

The driver (stoker) can leave the boiler only when the pressure in it decreases to zero, making sure that within 0.5 hour the pressure does not rise (due to heat accumulated by frosting).

It is forbidden to release water from the boiler without the order of the person responsible for the boiler room. Water shall be lowered only after pressure drops to zero, water temperature drops to 7080 С and masonry cooling. The descent should be carried out slowly and with the safety valve raised.

Before setting the boiler for dry preservation, all internal surfaces shall be thoroughly cleaned of deposits.

The boiler must be safely disconnected from all pipelines by plugs.

Drying of boiler inner surfaces is performed by passing hot air through it. At the same time open the drain valve on the superheated steam header (to remove the remaining hair in it) and the safety valve on the drum (to remove water vapors).

After careful drying of the boiler through open blades, install into the lower and upper drums prepared trays filled with quicklime or calcined calcium chloride (CaCl). After installation of trays, close the drums eyes with covers. Chemicals are not allowed to enter the boiler surface.

With a long stop, there is a need to replace the desiccant with fresh.

Boiler emergency stop

If one of the safety valves fails.

If the steam pressure has increased by 10% above the permitted pressure and does not decrease despite the measures taken (increased boiler supply with water, reduced load).

If the water level decreases below the permissible level. Makeup is strictly prohibited, which can lead to an explosion of the boiler.

If the level rises above the set elevation.

In case of failure of all water-indicating devices.

In case of failure of all feed pumps.

In case of detection of boiler main elements (drums, manifolds, screen and boiling pipes), breaks, cracks, stripping.

If the rarefaction decreases less than 0.5 mm of water. St.

When one of the burners goes OFF.

If the water flow through the boiler is below the set value.

If the temperature of the water downstream the boiler is higher than the set value.

At increase and decrease of gas and air pressure before burners.

When the power supply is stopped.

In case of fire threatening maintenance personnel and boiler.

In case of boiler emergency shutdown it is necessary to:

· stop gas, air supply, open the blowdown plug (close the valves on the burners and gate valves on the gas pipeline);

· monitor the water level in the boiler, close the main steam gate valve;

· make a record in the watch log about the causes and time of the boiler shutdown, inform the boiler manager about the boiler emergency shutdown.

In the event of a fire in the boiler room, the personnel shall call the fire department and take all measures to extinguish it without stopping the monitoring of the boilers.

2.4 Preservation and depreservation of CP

If the boiler is stopped for a long time, then it is necessary to preserve it. During preservation of boilers it is necessary to follow the instructions of the manufacturer's instructions for installation and operation.

Preservation of boilers. When the boiler is stopped for more than 30 days, it must be preserved, that is, protected from corrosion. Various conservation methods are used: dry, wet, gas, etc.

In a dry method, the boiler is thoroughly cleaned from scale, washed, all water is removed from it and dried by thorough ventilation. Then, trays with a substance that greedily absorbs water are placed in the drums of the boiler. The following substances are used: anhydrous calcium chloride, quicklime, silica gel, the amount of which should be 1.2, respectively; 3,1; 1.5 kg per 1 m3 of boiler vessel. Then plugs are installed on steam line, feed and blowdown pipelines and hatches of boiler drums are closed. Water absorber condition is checked first after a month and then every 2 months; with great moisturization, they are replaced.

In wet preservation method, cleaned boiler is filled with sodium hydroxide or trisodium phosphate solution. The substance consumption per 1 m3 of water when preparing a solution on condensate or nutrient water is 2 and 5 kg, respectively. The solution in the boiler is heated to boiling point (to remove air from it), and then the boiler is closed. This method is suitable in cases where it is not possible to reduce the boiler room air temperature below 0 ° C.

In gas preservation method, boiler cleaned from scale and sludge is filled through air valve with gaseous ammonia, and air is discharged through lower points of boiler. The pressure of ammonia in the boiler should be about 100 mm Hg. Ammonia, dissolving in the film of moisture remaining on the metal surface, forms an alkaline medium that protects the metal from corrosion.

2.5. Cleaning of CP

For inspection of drums and installation of devices in them, as well as for cleaning of pipes with cutters on bottoms there are oval lases with size of 325 ˣ 400 mm. Drums with an internal diameter of 1000 mm at pressures of 1.4 and 2.4 MPa are made of 16GS or 09G2S steel and have a wall thickness of 13 and 20 mm, respectively. Screens and boiling bundles of DKVR boilers are made of steel seamless pipes.

To remove sludge deposits, the boilers have end hatches on the lower chambers of the screens, for periodic blowing of the chambers there are nozzles with a diameter of 32x3 mm.

Repair of DKVR 1013 GM boiler

3.2. Repair of furnace devices

Burner is the basis of operation of any boiler. Its function is to burn the required amount of fuel. The boiler will only operate correctly if the burner is installed and installed correctly. The operation of the boiler depends entirely on the functioning of the burner. Also, safety, the number of harmful emissions, the efficiency factor and the life of the system depend on its serviceability. Modern burners are equipped with automation systems. But even automation tends to break, so in the event of malfunctioning burners, it is necessary to contact specialists in the replacement or repair of the burner.

Their repair consists in cleaning, replacing burned tips (nozzles) and splitter, cleaning channels and snails. When burning steel pipes or sections of steel body, defective sections are cut and welded new ones. In some cases, after 2-3 years of operation, the burner is replaced entirely.

3.3. Repair of auxiliary mechanisms

Auxiliary mechanisms of the switchgear include traction machines, smoke pumps, fans, etc.

All auxiliary mechanisms are put into current and overhaul repairs at the same time as the boiler unit is taken out for repair, and at the unit units - simultaneously with the equipment of the entire unit being taken out for repair.

If there is a reserve in the number or capacity of the mechanisms or if the boiler plant is operating at partial power, at which part of the mechanisms is disconnected from operation, then individual auxiliary mechanisms are repaired before the entire boiler is put into repair.

General operations during repair of auxiliary mechanisms are also assembly and disassembly of press and key joints.

3.4. Repair of auxiliary equipment

In general, a gas boiler plant is a combination of a boiler and auxiliary equipment. It includes the following main devices: boilers, economizers and air heaters. Boilers are its main part. Boilers in which steam is generated are called steam boilers; designed for hot water generation - hot water; generating water steam and hot water simultaneously - combined. In boilers, flue gases formed in the furnace device during combustion of gaseous fuel wash the heating surface of the boiler, giving it part of the thermal energy enclosed in them.

and leaving the boiler with a higher or lower temperature. For additional use of the heat contained in the flue gases leaving the boiler, the so-called tail heating surfaces are installed behind them - an economizer, in which feed or network water is heated, or an air heater, in which air going for combustion to the furnace device is heated. Depending on local conditions, economizers and air heaters sometimes do not install or install only one of these devices.

During operation of the boiler plant, natural wear of the main and auxiliary equipment is observed; it is also subject to various types of damage and contamination. This makes it necessary to restore worn out elements. Depending on the purpose, repair operations are divided into shift repair (inter-repair maintenance) and planned warning (preventive). The latter include current and major repairs. Inter-repair maintenance includes maintenance and supervision of the boiler room and various pipelines, as well as minor repairs of the equipment. As a result, the service life of the equipment is extended without reducing it

high-quality condition, faster and cheaper repairs. Inter-repair maintenance is not planned, it is performed by the staff of the watch and the locksmith on duty during the operation of the boiler equipment.

Planned preventive (preventive) repairs of boiler equipment are carried out according to the plan: routine repairs 2-3 times a year, overhaul - 1 time a year. The scope of work depends on the type of equipment and its condition. The current repair includes the following operations: partial disassembly of equipment; disassembly and check of individual units; repair or replacement of worn parts; inspection and detection of the condition of individual equipment elements; check and testing of repaired equipment. Depending on the technology of operations, the maintenance is carried out by a team with the participation of operational personnel at the equipment installation site or in the workshop.

The overhaul task is to restore the initial condition of the equipment and improve its performance by carrying out upgrades in all possible cases.

During overhaul, perform the following operations: complete disassembly of boiler equipment; Replace individual parts or features correction - all detected defects; check of repaired parts and parts; their testing, etc. Overhaul is carried out by a team or a specialized organization at the place of installation of equipment or in the workshop.

4. Technical control and regulatory documents

4.1. Periodic inspections and monitoring

Technical inspection of boilers, as well as steel structures of their frames (if any) includes:

a) external and internal inspection of the boiler and its components;

b) inspection of steel structures of the boiler frame (if any; according to the boiler operating manual (s);

c) hydraulic tests;

d) testing the electrical part.

Frequency of technical inspection

Pressure equipment shall be subject to technical inspection:

1) before commissioning after installation (initial technical examination);

2) periodically during operation (periodic technical examination);

3) before the period of periodic technical examination in cases (extraordinary technical examination):

a) equipment was not operated for more than 12 months;

b) the equipment was dismantled and installed in a new place, with the exception of transportable equipment operated by the same organization;

c) repair of equipment using welding, surfacing and thermal treatment of elements operating under pressure, with the exception of works, after which an examination of the industrial safety of the technical device is required:

- if more than 15% of anchor links of any wall are replaced;

- after replacement of drum, screen header, superheater, steam cooler or economizer;

- if more than 50% of the total number of screen and boiling or chimney pipes or 100% of steam superheaters and economizers pipes are replaced simultaneously;

- if such examination is required by the decision of the person responsible for the good condition and safe operation of the boiler based on the results of the inspection and analysis of the operational documentation.

The frequency, scope and methods of technical inspection of boilers shall be determined by the manufacturer and specified in the operating manual (instructions). In the absence of such instructions, the periodicity of technical inspections should be carried out at least :

a) once every four years - external and internal inspections;

b) once every eight years - hydraulic test.

4.2. Heat Engineering Tests

Heat testing of boilers is divided into three categories of complexity depending on their purpose:

The I complexity category includes acceptance tests, in which the boiler characteristics guaranteed by the supplier are checked.

The II complexity category includes operational (balance) tests of boilers: newly commissioned; overhauled or reconstructed; converted to gas fuel; operated at systematic deviation of parameters from standard ones.

The III category of complexity includes the mode and finishing tests of boilers (including after their overhaul), carried out in order to adjust the mode of their operation. The tests for complexity categories II and III differ in the number of experiments and the accuracy of the monitored parameters to be measured.

The tasks of balance tests include the definition of: individual components of the thermal balance; causes of excess of heat losses over calculated values (and development of recommendations for their reduction); characteristics of gas and air paths; economic performance of the boiler at nominal, minimum and two to three intermediate capacities; main components of heat consumption for own needs; progressive fuel consumption rates; optimal operating modes of the equipment.

Tests are carried out in a certain sequence: first, the sections of gas ducts and air ducts are calibrated for the correct installation of measuring devices, then a "photograph" of the boiler's work is obtained, air suction into gas ducts and a furnace is determined, fitting tests are carried out to determine the optimal excess air, testing burners, water economizers and traction machines, balance tests (under optimal operating conditions). During operational tests, some of the assigned tasks are solved comprehensively, which reduces the cost and simplifies the experimental part of the work, but increases the number of simultaneously organized measurements.

4.3. Maintenance and Repair Systems

The maintenance and repair system is a set of organizational and technological measures for the maintenance and repair of equipment.

Maintenance and maintenance system includes planning, preparation, implementation of maintenance and repair with specified sequence and periodicity.

The maintenance and maintenance system provides:

1) keeping the equipment operable and preventing unexpected failure of the equipment;

2) correct organization of maintenance and maintenance;

3) possibility of performing repair works according to the schedule agreed with the production plan;

4) timely preparation of necessary spare parts and materials.

4.4. Types of repairs

The following types of boiler equipment repairs are distinguished: current - at the expense of working capital; capital - at the expense of depreciation deductions; restoration - at the expense of special funds (state reserve or insurance fund). In addition to these types of repairs, during the operation of boiler equipment, overhaul services are carried out, including equipment care

(equipment is lubricated, rubbed, cleaned, regularly inspected to determine the degree of wear of parts and their timely replacement, heating of friction surfaces is checked, smoke pumps and fans are checked, pipelines and special devices are purged) and minor repairs of equipment (correction of small defects, mainly on external fasteners, lifting of fasteners, elimination of defects in drives and fences, washing and wiping them). Inter-repair maintenance is not planned and is carried out during the operation of boiler equipment.

Routine repairs are carried out to ensure normal operation of the boiler and auxiliary equipment with rated power and capacity.

During the current repair, boilers are partially disassembled, inspected, separate units are disassembled, worn parts are repaired or replaced, measurements are made and state of parts or units is determined, preliminary list of defects is made, drawings are made or checked for spare parts.

Overhaul is carried out to bring the technical parameters of the equipment to design and design values. The scope of overhaul of the steam boiler includes complete external and internal inspections with condition check and determination of the degree of wear of the heating surfaces of drums, headers, valves, pipelines, coating, insulation, framework, rotating mechanisms, etc. Note here that worn units and parts are replaced and restored, external and internal cleaning are performed.

At the same time as major repairs, work should be carried out to improve the equipment, its modernization and normalization of parts and assemblies, as well as work prescribed by emergency and operational circulars. Normalization is a reduction in the assortment of parts and assemblies in the workshop equipment.

This allows the principle of interchangeability to be used more fully. On boilers, replaceable parts are parts of the pipe system: boiling and screen pipes, superheater coils and economizer; dust, gas and fuel oil burners.

4.5. Repair plans and schedules

In order to ensure reliable operation of the equipment and prevent faults and wear and tear, the enterprises periodically carry out scheduled preventive repair of the equipment (PPR). It allows you to carry out a number of works aimed at restoring equipment, replacing parts. This ensures cost-effective and continuous operation of the equipment.

Competent implementation of the PPR involves:

planning of planned preventive repair of equipment;

preparation of equipment for preventive maintenance;

carrying out of planned preventive repair of equipment;

carrying out measures related to planned preventive repair and maintenance of equipment.

The scheduled maintenance system includes the following types of maintenance and maintenance:

weekly maintenance,

monthly maintenance,

Annual preventive maintenance.

4.6. Duration of KP outages related to maintenance and repair

Current repairs are carried out as required for the boiler 3 times during the year, but at least once a year. Minor defects detected during operation of the boiler (soaring, dusting, suction cups, etc.) are eliminated without stopping it, if this is permitted by safety regulations. If it is not allowed to perform work to eliminate minor defects on the operating boiler, the boiler must be stopped for ongoing repairs.

Overhaul should be carried out once every 1-2 years. It is allowed to extend the period between repairs, if in its condition the boiler can provide further reliable operation.

Repair and maintenance base

5.1. Organizations performing maintenance of CP

The service of repair of technological equipment of a machine-building enterprise - the service of the chief mechanic (SGM) - is a complex of departments engaged in supervision over the operation and repair of technological equipment. It includes the department of the main mechanic (OGM) of the plant with the workshops included in it: repair and mechanical (RMC), repair and foundry and boiler welding (mainly in large plants), as well as workshop repair bases (CRB)

The organization of equipment maintenance and repair at the enterprise involves the creation and functioning of specialized structural subdivisions that implement the functions of equipment maintenance and repair, as well as the necessary documentation (standards, regulations, rules.) Governing the creation and operation of these subdivisions. The structure of maintenance and repair services in modern enterprises should correspond to their size, specialization, scale of activity, available resources and specific features. Depending on the parameters of the enterprise (scale, specialization, form of organization of production), both a small maintenance department and a fairly large equipment service can be organized on it. In most cases, in small and some medium-sized enterprises, equipment maintenance and repair (usually excluding ongoing maintenance operations and minor repairs) is carried out by specialized third-party organizations, as well as equipment suppliers (warranty and post-warranty repairs). At a large machine-building enterprise, plant-wide and workshop maintenance and repair units are organized to carry out maintenance and repair functions.

At a large machine-building enterprise, plant-wide and workshop maintenance and repair units are organized to carry out maintenance and repair functions. Among them, we highlight the department of the chief mechanic, which includes the design bureau for equipment repair, the production and planning bureau, the repair and tool shop, individual warehouses of spare parts and materials, repair sites in individual workshops, the dispatch bureau and some

Other departments (depending on the specifics of the enterprise). This department performs design, technological, production and planning and economic work for the entire repair facility of the enterprise. In the repair shop, equipment maintenance and repair teams are formed. Their main tasks - to carry out preventive maintenance of the equipment and in case of equipment breakdown and its shutdown - to come to the site immediately after the call and eliminate the detected failures as quickly as possible.

5.2. Equipment of repair enterprises with mechanisms and equipment

When repairing boiler equipment, as well as during construction and installation work, mainly inventory prefabricated metal scaffolds are used. These forests have the following advantages over wooden forests: it takes less time to assemble and disassemble them, the cost of building materials is also less, while the safety of work is higher. Wooden forests are installed only in places where work is rarely carried out and therefore the manufacture of metal forests is impractical.

The use of certain structures of metal scaffolding is determined by many reasons - the type of boiler, the presence of materials for the manufacture of scaffolding, the presence of the project, and the experience of personnel. Any scaffolding design shall satisfy the following conditions: safety of operation; Ability to assemble and disassemble quickly easy check of attachment of scaffold elements at their acceptance; possibility of installation on the whole or limited area - at one, two, three or four walls of the furnace; the possibility of installing any number of tiers within the height of the furnace; reliability and stability under load; small mass and transportability of elements; processability (ease of manufacture); versatility and interchangeability of elements .

Rigging, machinery, equipment and accessories are also used in the repair of heating equipment. Rigging, which is widely used in the repair of thermal equipment, is called horizontal and vertical movements of equipment performed by special lifting devices (rigging).

During rigging, various equipment is used: winches, blocks, polyspasts, jacks, tali, cranes, as well as various equipment: ropes, slings, cowls, clamps, talreps.

The winch serves to convert relatively small torque on the drive shaft into large torque on its drum by reducing the rotation speed of the drum compared to the rotation speed of the drive shaft (handle). The greater the torque on the drum, the greater the traction force on the rope wound on the drum, and therefore the greater the load capacity.

Winch consists of drum, reduction gear, drive and frame (frame). Winch drum is connected with gear, worm or belt drive. Depending on the purpose, winches are made of different carrying capacities. The reduction gear system has a braking device that prevents spontaneous lowering of the load.

Conclusion

Operation of boilers shall ensure reliable and economical generation of steam or hot water of required parameters and safe working conditions of maintenance personnel. In order to achieve these requirements, the operation of boilers must be carried out in strict accordance with the current rules, norms and guidelines, in particular in accordance with the "Rules for the construction and safe operation of steam and hot water boilers," "Rules for safety in the gas industry" Rostekhnadzor, "Rules for the technical operation of heat-using plants and heating networks, etc.

On the basis of these regulations, job descriptions and process instructions for equipment maintenance, repair, safety, prevention and elimination of accidents, etc. shall be drawn up for each boiler plant.

Technical passports shall be drawn up for equipment, as-built, operational and process diagrams of pipelines of various purposes and electrical connection diagrams.

Knowledge of the instructions, the boiler operating mode charts and the above mentioned materials is mandatory for the maintenance personnel, and only under this condition can he be allowed to work. Staff knowledge should be systematically tested.

Responsibility for the serviceable condition and safe operation of boilers is assigned by the order of the enterprise to the head of the boiler house, and in the absence of the boiler head, to the engineering and technical worker who performs the functions of the head of the boiler house.

Those responsible for the good condition and safe operation of boilers should have a special heat engineering formation, otherwise special training and certification by a commission with the participation of the inspector of Rostekhnadzor is necessary.

People under 18 years of age who have undergone a medical examination, have been trained, certified and have a certificate for the right to service boilers are allowed to service boilers.

Training and certification of boiler house operators should be carried out in vocational schools, training and course mills or in special courses on the basis of standard programs agreed with Rostekhnadzor. Certification of boiler operators is carried out by a commission with the participation of the inspector of Rostekhnadzor.