A hot water boiler is a device for heating coolant used in a heating system.
The advantages and benefits of a hot water heating boiler are beyond doubt, but like any technical means, boilers periodically require maintenance.
Maintenance Description
Boiler maintenance has its own characteristics, which are related to the design and operation of heating units.
The boiler produces under pressure while being connected. In order for heating system installations to work properly, periodic maintenance measures such as purging water boilers, cleaning and preservation are necessary.
All boiler maintenance measures must be carried out in a timely and efficient manner. It is preferable to trust maintenance to professionals, but it is also possible to independently understand issues related to the care of this equipment.
Maintenance activities:
- Cleansing from salt deposits.
- Pressure gauge operation test.
- Checking and cleaning the heating element.
- Checking automation and safety devices.
- Diagnostics of shut-off valves operation.
- Replacement of water circulation tubes.
- Washing and purging of functional parts of hot water boilers.
- Preservation of equipment.
More attention should be paid to the maintenance of hot water boilers, since heating equipment and regular maintenance- integral concepts.
Exceptionally correct maintenance of boiler units ensures their uninterrupted and long service with minimal loss of efficiency.
Types of maintenance
cubic meter water, after which the standard alkalization procedure is carried out.
Boiling is carried out throughout the day, then most of the water is removed (more than 50%) and the initial solution is added.
If necessary, the procedure is repeated. After the end of alkalization, sludge with water is released. Finally, mechanical cleaning is performed.
Preservation of a water heating unit: wet, dry and gas methods
If the boiler needs to be stopped long time, then it is preserved. When preserving boilers, it is necessary to use the manufacturer’s instructions for installation and operation.
Preservation of a hot water boiler can be carried out using several methods, the most common of which is the wet method.
This technique involves pouring an aqueous alkaline solution with a concentration of 0.5% into the unit.
If the water has not passed through beforehand, you will need to bring it to a boil inside the boiler container with the safety valve open.
By boiling, gases dissolved in water, carbon dioxide and hydrogen, are removed from the solution. Then, the heating unit is hermetically sealed. After a while, the alkali concentration is checked (if necessary, alkali is added).
The dry boiler preservation method is used less frequently. After cleaning the equipment from the accumulated scale and drying, substances that absorb moisture are placed in the drums - for example, quicklime (at a rate of at least 2 kilograms per cubic meter of water).
You can also use calcium chloride for these purposes, which is used at the rate of 1 kilogram per cubic meter of water. After this, the boiler is hermetically sealed.
The gas method of equipment preservation involves cleaning the equipment from scale and drying it.
Nitrogen is pumped from the cylinder through the drain valve, while the air is released through an air vent or safety valve, where a burning candle is installed, which serves to determine the nitrogen level.
After the nitrogen displaces the air, the candle goes out. Next, the boiler is closed, a pressure of 100 to 200 Pa is pumped into it (the pressure is maintained during the conservation period).
Must undergo periodic maintenance. At the same time, it is advisable that all necessary maintenance items be performed by qualified specialists.
If the equipment needs to be stopped for a long time, it is preserved.
Boiler servicing
What are the requirements for workers servicing boilers?
Persons at least 18 years of age who have undergone a medical examination and passed exams under the program for training stokers (operators) are allowed to service boilers. When servicing gas-fired boilers, you must additional training. At least once a year, knowledge is retested.
What documents are used to guide the operation of boilers?
Hot water and steam boilers with steam pressure up to 0.7 MPa (0.7 atm) are operated in accordance with the Rules for the design and safe operation of hot water boilers and steam boilers with a pressure not exceeding 0.7 atm, approved by Gosgortekhnadzor.
Boiler with more high pressure steam is maintained in accordance with the Rules for the Design and Safe Operation of Steam and Hot Water Boilers, approved by Gosgortekhnadzor with additions and changes specified in the instructions for these boilers.
Who is responsible for the maintenance and safe operation of hot water and steam boilers?
The manager of the boiler room is responsible for the maintenance and safe operation of hot water and steam boilers, as well as boiler room equipment.
If there is no position of boiler room manager, the person in charge is appointed by order of the enterprise from workers with special technical education. The appointment of a boiler room manager or a responsible person from among practical workers is permissible subject to verification of their knowledge by the qualification commission of enterprises.
What are the requirements for the boiler room?
Hot water and steam boilers can be installed in separate buildings, in premises adjacent to housing, public or production premises, separated from them by a firewall; in the lower or basement floors of residential, public and industrial buildings, provided that the boiler room is fenced with fireproof structures.
It is forbidden to install boilers in rooms adjacent to or located under a warehouse for combustible materials (excluding fuel warehouses for the boiler room itself), and where there is or may be at the same time large number people. The boiler room walls and ceilings are made fire resistant. The height of boiler rooms is set at least 3.2 m.
The distance from the platforms to the control and measuring instruments, boiler, fans, electric motors, as well as from the lower protruding structural elements or the ceiling of the boiler room is provided for at least 1.9 m.
When heating with solid fuel and manual maintenance, the distance from the front of the boiler or the front of the remote firebox to the opposite wall should be equal to the length of the boiler firebox, increased by 1 m; when heating boilers with liquid or gaseous fuel - at least 1 m from the burner devices.
The width of the passages between boilers or between the boiler and the wall of the room is left at least 1 m, and between individual protruding parts of the building, stairs, working platforms, etc. - at least 80 cm.
In boiler rooms with a total floor area of up to 200 m2, one exit is allowed, and over 200 m2, at least two exits to the outside, located on opposite sides of the room. Exits from the boiler room to the outside (except for spare ones) are equipped with vestibules or other devices that trap cold air.
The air temperature in the boiler room in winter should not be lower than + 12°C, and in summer no more than 5°C lower than the outside air temperature in the shade.
Doors from the boiler room to service, utility and other premises must open towards the boiler room and have devices for self-closing.
For convenience and safe maintenance of boilers, permanent stairs and platforms made of fire-resistant materials, equipped with metal railings, are installed.
The boiler room is equipped with a toilet, washbasin, shower and changing room, as well as sufficient ventilation.
The height of the ash rooms from the floor to the lower surface of the ceiling is set at least 2.6 m, and the height of the ash corridors from the floor to the lower protruding parts of the ceiling is 1.9 m. The width of the passage in the ash room must be no less than the width of the trolley or wheelbarrow used and two passages on each side of 70 cm. In the ash room, regardless of the number of boilers, two exits are made in opposite directions.
It is mandatory to have fire-fighting equipment in the boiler room. In the boiler room, the Rules for Stokers and Stokers, as well as the Internal Regulations and special maintenance instructions are posted in a visible place. gas equipment and gas pipeline diagrams.
It is prohibited to store foreign objects, especially flammable ones, in the boiler room.
For what reasons can a boiler explode?
First of all, the boiler may explode due to the steam pressure exceeding established by the instructions or due to destruction of the boiler wall.
Steam pressure above the permissible level usually increases due to a malfunction of the safety valves, scale deposits on them and their sticking to the seats, additional weight hanging on the lever valve, or jamming of the levers.
When the water level in a steam boiler drops below the fire line, the surface of the wall exposed to water loses strength under the influence of high temperature and may collapse. The formation of a large layer of scale or sludge on the walls of the furnace of a steam boiler contributes to overheating of the walls of the furnace, which, when heated, swell and burst even with a slight increase in steam pressure in the boiler.
What are the main safety measures when servicing boilers? low pressure to
7 MPa (0.7 atm)?
Pressure gauge, water indicator glass, steam and water test valves, hydraulic seal or safety valves, feed and ( check valves, drain valve, steam shut-off valve and feed pump must always be in good working order. The boiler cannot be put into operation if at least one of these devices is faulty. Their serviceability is established before the boiler is started.
Before lighting the boiler, ventilate its firebox and chimney for 10...15 minutes.
When the boiler is operating, monitor the pressure gauge readings, not allowing the steam pressure to exceed, and the water level in the water indicator glass.
The boiler is stopped immediately if, despite the measures taken, the pressure in it continues to increase and the water level decreases, as well as in the event of failure of control and feeding devices, cracks or leaks in welds or combustion of fuel in gas ducts.
8 What is the maintenance of steam boilers?
Any malfunctions of the boiler, furnace, instrumentation and communications are immediately corrected.
Malfunctions of boiler components and communications that are under pressure or exposed to heat from the furnace or steam are eliminated when the boiler is not working.
During boiler maintenance, at least after 10 days continuous operation, clean from soot chimney and after 30 days - the heat chamber.
The boiler is descaled at least once every 6 months in this way: fill the boiler with clean water to the level of the limit mark on the water meter tube, bring to a boil. Then a solution of 2-5 kg of caustic soda is poured into the boiler and the boiler is kept in operating condition for 8 hours.
Having stopped work and cooled the boiler, drain the contents of the boiler, partially disassemble it, mechanically clean the heating surfaces of scale, then assemble the boiler and subject it to a hydraulic test.
What precautions are used when stopping steam boilers, water heaters and steam generators for a long time?
When boilers are stopped for a long time in heated rooms or in the summer, they are cleaned of soot and scale, filled completely with water and disconnected from the water supply system.
When stopping boilers installed in unheated rooms in cold weather, they are also cleaned of soot and scale, followed by washing and hydrotesting, but the water must be drained from the boiler-water heater, pump and pipelines.
Water heating boilers KVR.
1. INTRODUCTION
The technical description is a guide for the installation, operation and transportation of the ASK Group of Companies water heating boiler. Contains information about the boiler design.
2 . PURPOSE
A hot water boiler with a heating capacity of 0.688 Gcal/hour is designed to heat water up to 95 0 C, intended for heating systems in residential, industrial and warehouse premises with a total area of up to 8000 m 2 . Simultaneously with the boiler, a heater designed to obtain hot water, used for household and industrial purposes for disposal.
A water-tube boiler creates a natural circulation of water in the heating system, in which you need to have at the top point expansion tank, open type. When using a circulation pump creating a pressure of up to 6.0 kg/cm 2 , the heating system is made closed using safety valve at the boiler outlet.
The boiler is designed for layer combustion of any type solid fuel(firewood, coal, peat). Atinstallation of the boiler in a specially equipped room, with the use of additional devices, it is allowed to burn liquid and gaseous fuel(clarified kerosene, diesel fuel, diesel oil, natural or liquefied gas).
The high degree of softness of the water used creates conditions for long-term operation of the boiler and heating system. The boiler pipe system is thermally insulated from the outside mineral wool and covered with a casing made of 2 mm thick steel sheet.
Installation of the hot water boiler and heating system should be carried out in accordance with the heating scheme of the building. To ensure normal circulation in horizontal areas, it is necessary to create a slope of at least 0.01 0 hot water pipelines from the highest point, with a decrease to the heating elements, and the slope of the return water pipeline with a decrease to the boiler.
3. TECHNICAL DATA
Basic technical data and parameters of the hot water boiler.
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Options |
Boiler brand |
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KVR-0.2 |
KVR-0.5 |
KVR-0.8 |
KVR-1 |
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Heating capacity, MW (Gcal/h) |
(0,172) |
(0,430) |
(0,688) |
(0,860) |
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Estimated efficiency, % |
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Water temperature chart, o C |
60-95 |
60-95 |
60-95 |
60-95 |
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Working pressure, MPa (kgf/cm 2 ) |
0,6 (6) |
0,6 (6) |
0,6 (6) |
0,6 (6) |
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Fuel consumption (coal), kg/hour |
39,2 |
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Boiler volume, m 3 |
10,4 |
12,4 |
17,7 |
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Boiler heating surface, m 2 |
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4. PRODUCT COMPOSITION
The product includes an all-welded design of the boiler pipe system block. The boiler is thermally insulated with mineral wool, covered with a casing, and equipped with three doors: firebox, ash pan and ash pan. Pressure gauges and thermometers, five grate bars, safety valves.
Installation, lining and adjustment work can be carried out at the request of the customer, by a visiting team of the enterprise, at the boiler installation site.
By agreement with the customer, the boiler can be equipped with furnace tools and auxiliary equipment
5. STRUCTURE AND OPERATION OF THE BOILER
5.1 Boiler design
The boiler is a transportable, non-dismountable block in the form of a firebox and a convective part, installed on an ash pan block (Fig. 1). At the bottom of the boiler there is a belt of collectors (longitudinal Ø159x5, transverse Ø133x5 mm), to which water cooled in the heating system is supplied through a DN 100 supply pipe. 5 grates measuring 900x220 mm are placed inside the lower belt of the collectors.
The boiler firebox is a closed volume, shielded by walls made of pipes Ø51x2.5mm.
In the front part of the firebox there is a door measuring 400x400 mm. Under the firebox, in the ash pan block, there is an ash pan with a door measuring 400x400mm and a blow air input window measuring 250x250mm.
The convective part of the boiler is made in the form of downward and upward flue ducts, each of which has 12 sections. Riser pipes Ø83x4 mm, convection pipes Ø51x2.5mm.
The flue ducts of the convective part are separated from the firebox and betweenconsisting of two-light gas-tight walls (4x30mm strip). Under the convective block, in the block, there is an ash pan, which has on the left or right side door dimensions 400x400 mm. In the upper part of the boiler there is an upper belt of collectors made of pipes (longitudinal Ø159x5, transverse Ø133x5) with 4 sling eyes. The boiler ceiling is shielded with pipes Ø83x4mm, embedded in a collecting manifold Ø133x5mm from which hot water is discharged through a DN100 pipe, and then into the heating system of the building.
On the outside, a 4x30 mm strip is welded between the pipes. The entire pipe system of the boiler is lined with heat-insulating mats made of basalt wool and sheathed with a casing made of 2 mm sheet.
Water flows through the shielding walls and elements of the boiler in accordance with the circulation scheme.
5.2 Operation of the hot water boiler
5.2.1. The flue gases, having reached the top of the firebox, turn 180 O and through the convective part are directed into the flue, from where they enter the chimney of the boiler room.
5.2.2. Water enters the boiler through the inlet pipeline. It is possible to install a mixing water pump, which is installed between the direct and return water supply. With the help of a mixing pump, the temperature of the return water entering the boiler rises to 60°C.Water is discharged from the boiler through the outlet pipeline.
5.2.3. Construction and operation of instrumentation and automation according to the documentation supplied with the kit.
6. CONTROL AND MEASURING INSTRUMENTS
An indicating pressure gauge and thermometer are installed on the return water pipe.
A pressure gauge is installed on the direct water inlet pipe.
7. PLACEMENT AND INSTALLATION
7.1. The boiler must be installed in separate rooms that meet the requirements of SNiP 2.01.02-85
7.2 Installation of the boiler must be carried out in accordance with the “Rules for the design and safe operation of steam boilers with a steam pressure of no more than 0.7 kgf/cm 2 : hot water boilers and water heaters with water heating temperature not exceeding 115 °C” and according to the boiler room design.
7.3 During installation, care should be taken to ensure that the boiler is installed strictly horizontally to the boiler room floor level.
8. TRANSPORTATION AND STORAGE
8.1. Boilers can be transported by any type of transport in compliance with measures to ensure their safety.
8.2. The boiler may only be lifted using the lifting eyes installed for this purpose. When lifting and installing, special care must be taken to avoid dropping or shaking the boiler so as not to damage the lining or insulation of the boiler.
The conditions for transportation and storage of boilers must comply with the requirements of group 5 of GOST 15150-69.
8.3. Storing boilers for 1 to 3 months is considered short-term. Over 3 months - long-term.
8.4. Short-term storage is allowed under enclosing structures that protect the boiler from precipitation.
8.5. Long-term storage should be carried out in special rooms that must meet the following requirements:
the premises must be dry, ventilated, and protect the boiler from precipitation;
positive temperatures are maintained in the premises in winter;
The dimensions of the room ensure free placement of the boilers.
8.6. During storage, the outer surfaces of boilers must be cleaned of dirt, washed and dried.
8.7. Clean boiler flues from contamination. Drain the water completely. After draining the water, dry the inside of the boiler.
9. STARTING AND STOPPING THE BOILER
At the same time, in order to avoid the formation of condensation in the heat exchange elements, the initial start-up of the boiler and its transition from a cold to a hot state must occur slowly. The recommended heating rate of water in the boiler should not exceed 1+1.5 °C/min.
When starting the boiler after a short period of inactivity, the boiler load and water heating temperature can be increased somewhat faster, but not more than 2 °C/min.
If these requirements are violated during the initial start-up of the boiler, condensation may form in the heat exchange elements.
9.1. Stopping the boiler in all cases, with the exception of an emergency stop, must be carried out only with a written order from the administration.
When stopping the boiler you must:
Stop fuel supply to the firebox;
Disconnect the boiler from the pipeline after combustion in the furnace stops. If, after disconnecting the boiler from the pipeline, the pressure in the boiler increases, refuel the boiler and purge;
Cool down the boiler and drain water from it;
Ventilate the firebox and flue for 10-15 minutes, turn off the pump and vent;
De-energize the voltage shield;
It is prohibited to drain water from the boiler without the order of the person responsible for the good condition and safe operation of the boiler room. The drainage of water should be carried out slowly; the pipe part should communicate with the atmosphere using an air collector and a three-way pressure gauge valve.
The procedure for preserving a stopped boiler must comply with the instructions in these instructions.
To stop the boiler for a short time, there is no need to interrupt the water circulation.
Despite the fact that the boiler room has the necessary technological equipment, and all the necessary measures for the preparation of boiler water have been completed, however, during long-term operation, due to the lack of proper control on the part of the operating organizations over the operation of the water treatment equipment, solid deposits in the form of scale form on the internal walls of the heat exchange elements of the boilers. To remove scale, boilers are chemically cleaned. Chemical cleaning of boilers is carried out using alkalis or acids (trisodium phosphateNa 3 P.O. 4. sodium hydroxide NaOH, hydrochloric acidHCL).
Cleaning with trisodium phosphate is carried out in the following sequence:
The boiler is disconnected from the heating network, the water pressure in the boiler is reduced to 0.5 Atm and chemicals are introduced into the boiler from a special tank. reagents trisodium phosphate at the rate of 1.5 kg per 1 m 3
boiler water, turn on the mixing pump. After 2 hours, part of the boiler water is drained into the drainage and additional trisodium phosphate is introduced at the rate of 0.75 kg per 1 m 3
boiler water. The mixing pump is turned on again to circulate water in the boiler and the boiler is “boiled down” for 5-6 hours, while it is necessary to monitor the temperature and pressure of the water in the boiler, after which the boiler is cooled, the water is drained, the boiler is washed and filled with chemically purified water.
Acid cleaning of boilers is more effective in removing scale, compared to alkaline cleaning. But since acid washing is classified as a hazardous type of work, its implementation can only be entrusted to organizations licensed for this type of activity.
9.2 Emergency stop of the boiler
9.2.1. The boiler must be immediately stopped and disabled by protection or personnel in the following cases:
Safety valve malfunction detection;
If cracks, bulges, or gaps in welds are found in the main elements of the boiler;
Reducing water flow through the boiler below the minimum permissible value;
Reducing the water pressure in the hydraulic circuit of the boiler below the permissible level;
The pressure has risen above the permitted limit by 10% and continues to rise, despite the cessation of fuel supply and increased water supply to the boiler;
The feed pump has stopped working;
The power supply has been interrupted, and the boiler elements have been damaged, creating a danger for operating personnel or the threat of destruction of the boiler;
Malfunctions of automatic safety or alarm systems, including loss of voltage in these areas;
A fire occurs in the boiler room that threatens personnel or the boiler.
9.2.2. The procedure for emergency shutdown of the boiler must be specified in production instructions. The reasons for the emergency shutdown of the boiler must be recorded in the shift log.
10. OPERATION AND MAINTENANCE
10.1 Operating procedure
After installing the boiler and connecting it to the space heating system, it is necessary to fill the system and boiler with water and carry out an inspection. The grate bars are installed after hydraulic testing and inspection.
When lighting the boiler, perform the following work:
1. open the chimney damper, firebox and ash door;
2. remove slag and ash from the firebox and from the ash pit;
3. put in the firebox on the grates required quantity firewood;
4. Place lump coal on the firewood;
5. light firewood in the firebox;
6. close the firebox door and adjust the supply of the blower fan or the opening of the blower door according to combustion;
7. When burning wood and coal is stable, add the required amount of coal evenly throughout the firebox.
10.2 Maintenance
10.2.1 Maintenance consists of periodic inspections, blowing, cleaning of the boiler and its repair.
10.2.2 List of maintenance activities.
In order to ensure reliable operation of the hot water boiler, it is recommended to carry out the following measures:
Visual inspection of leaks;
Checking the drainage pipe;
Checking flange connections;
Blowing;
Complete cleaning, checking heating surfaces.
10.3 Blowing and cleaning the boiler
10.3.1. In order to ensure flawless and more economical operation of the boiler, blowing should be done quite often. When the flue gas temperature increases by 30-40 O With a higher gas temperature of a clean boiler at the same load, the boiler should be blown. Blowing the boiler should also be carried out if the resistance of the boiler gas path increases significantly.
10.3.2. The boiler is cleaned from soot through the doors of the firebox and ash pan. Cleaning can be done either manually or with a mechanized brush (brush). When cleaning with a power brush, care must be taken to avoid damaging the pipes.
10.3.3. Internal inspection and cleaning of the firebox is carried out during the summer shutdown of the boiler. All accumulated soot and dirt are removed from the walls of the firebox and convective part using a steel brush.
10.3.4. Internal inspection, flushing and cleaning of the water path should be carried out in summer period boiler downtime annually. Inspect the boiler through the firebox and ash pan doors.
The boiler is cleaned of boiler stone and sludge using a chemical method. Chemical cleaning is carried out with a 5% solution of hydrochloric acid, inhibited by a mixture of PB-5 - 0.1% with hexamine - 0.5%; or a mixture of PB-5 with urotropine and OP-10 at a temperature of 60-65°C. The circulation time of the solution is from 6 to 8 hours at a speed along the path of 1-1.5 m/sec.
After cleaning, flush the boiler by removing all deposits of dissolved scale and sludge from it through the lower drain pipe. After which it is necessary to fill the boiler with treated water as quickly as possible. If such a composition is not available, the boiler should be heated to operating temperature and aerated effectively.
10.4 Boiler repair
Repairs to the boiler during the warranty period can only be carried out with the written permission of the manufacturer.
After the warranty period, boiler repairs can only be carried out by a company that has the technical means necessary to perform the work efficiently.
10.5 Safety precautions
10.5.1. Required for maintenance strict adherence security measures. Repair work must be carried out in strict accordance with the norms and rules for the production of repair work.
10.5.2. Repairs, cleaning and inspection of the boiler may only be carried out after appropriate instruction at the workplace.
10.5.3. Work inside the boiler can only be carried out when the boiler is sufficiently cooled. Before starting work, the boiler must be ventilated.
10.5.4. It is prohibited to work in the firebox and convective part with a temperature above 60°C.
10.5.6. Boiler repairs should be carried out with water and air turned off, and power removed from the automation system.
10.5.7. Inspection, lubrication and repair of component equipment is carried out in accordance with the operating instructions for the relevant products.
10.5.8. Do not allow burning coal to fall onto the floor. The distance from the boiler to combustible structures must be at least 2000 mm.
10.5.9. It is unacceptable to leave firewood, coal, flammable objects or dry clothes near a lit boiler.
10.5.11. It is prohibited to use flammable fuel or explosive substances (gasoline, kerosene, acetone, etc.) to light the boiler.
10.5.12. When the boiler is running, the water temperature must not rise above 100 0 C, when the temperature rises, it is necessary to reduce fuel combustion by closing the blower fan gate or the blower door and reducing the draft or increasing the water flow.
11. PRESERVATION OF THE WATER BOILER
The procedure for preserving the boiler for long-term storage must comply with these instructions.
Preservation of the boiler for a period of up to one month should be carried out using the wet method, for this it is necessary:
Stop the boiler according to the instructions;
Disconnect the boiler pipeline from the general lines;
Fill the internal volume of the boiler with a protective solution: sodium hydroxide 1000 mg/l, phosphoric anhydride 100 ml/l and sodium sulfate 200 mg/l;
Before starting a boiler that has undergone wet conservation, open the system, release the alkaline solution and rinse with clean water;
If the boiler is stopped for a long time (more than one month), preservation must be done using a dry method, for this it is necessary:
Stop the boiler according to the instructions;
When the pressure in the boiler is equal to half the working pressure, purge the boiler according to the instructions;
After the temperature drops to 50-60ºС, drain the water from the boiler;
Clean the heating surface from scale and sludge;
Dry the inside of the boiler by blowing with compressed air;
Place previously prepared baking trays filled with quicklime into the collector (1 kg in each collector, or anhydrous calcium chloride, 0.5 kg each in each collector).
Before putting a dry-preserved boiler into operation, it is necessary to remove the trays with lime (calcium chloride) from the collectors.
Preservation and depreservation of devices, protection, control and auxiliary equipment in accordance with the installation and operation instructions of the manufacturers of these devices and equipment.
Power supply to a boiler that is undergoing conservation must be excluded.
12. GENERAL INSTRUCTIONS
12.1. Capital and current repairs hot water boilers must be produced in accordance with specially developed schedules. Minor defects discovered during operation must be eliminated as soon as possible with the boiler running (if operating rules allow) or whenhis stop.
12.2. Safety measures during operation, preparation for work, operating procedure, measurement of parameters, adjustment and configuration, testing technical condition during operation, characteristic malfunctions and methods for their elimination and maintenance must be carried out in accordance with the relevant sections technical description boiler
This instruction has been developed on the basis of: - Rules technical operation thermal power plants, approved by the Ministry of Energy of Russia No. 115 dated March 24, 2003 - Rules for the design and safe operation of steam boilers with a steam pressure of no more than 0.07 MPa (0.7 kgf/cm 2) water heating boilers, water heaters with a water heating temperature not higher than 338 K (115 ° C ), approved by the Ministry of Construction of Russia No. 205 dated August 28, 1992. 1.1. A person responsible for the safe operation of the boiler room must be assigned to the boiler room from among the engineers and technicians of the EMU service. 1.2. Persons at least 18 years old are allowed to service the boiler room: the operator of the EMU boiler service and persons from the operational dispatch service who have completed training, passed the exams of the certification commission, have a certificate of the established form for the right to service boiler installations and are allowed by order of the enterprise to perform these works. 1.3. Ignition of the boiler before the heating season is carried out after written permission in the boiler room passport of the person responsible for the safe operation of the boiler room. 1.4. Purpose of the boiler: production of high-temperature coolant (hot water); type of fuel – natural gas; design parameters: water pressure, MPa (kgf/cm2) – 0.7 (7.0) water temperature, °C – up to 115 heating capacity, Gcal/h – 2.0. 1.5. Maintenance and repair of boiler equipment is carried out by: - heat and power equipment - by the EMU service; - control, measuring and automation by the instrumentation and automation service; - gas equipment - by the gas distribution system service.
2. PREPARING THE BOILER FOR OPERATION
2.1. When preparing to start up the boiler room, it is necessary to take the FOLLOWING MEASURES: - ventilate the boiler room with a fan or open windows and doors for 10-15 minutes; - after ventilation, the gas content in the room is checked using a gas analyzer. - inspection of pumps, pipeline circuits, supports, fittings, insulation of flange connections, settling filter; - inspect all gas valves and valves, normal position - all purge plugs must be open; - after opening the valves at the inlet and outlet of the boiler, fill the heating system with network water, bleed air through the vents from the heating system - turn on circulation pump and bring the water pressure in the heating system to 2.0-4.0 kgf/cm 2 - conduct an external inspection of gas equipment. 2.2. Before starting the boilers, an external inspection of the chimneys is carried out, and if there is a break for a long time, the internal surfaces are also inspected. External inspection is carried out on supports, compensators, control valve, explosion valve, insulation, manhole gaskets. There is a blockage that will prevent the boiler from starting when the control valve is closed valve 2.3. When gas is supplied, the tap is opened and the corresponding valve to the boiler is purged for about 5-10 minutes, after which the purge valve is closed. 2.4. When the network is full, the valves must be opened. Softened water is supplied to the boilers through taps. When filling the network and water supply circuit with water, close all valves to remove air. 2.5. To turn on the network pumps, after filling with water, open the valves and close the valves and then turn on the selected network pump 2.6. If during the heating season the temperature of hot water at the inlet and outlet of the boiler room is adjusted, then the temperature of the water at the inlet to the network pumps should not exceed 80°C. 2.7. Turning off one network pump automatically turns on another. If both pumps fail, the control valve opens to allow natural circulation in the network. When the boiler room is turned off, the network pump is stopped and the shut-off valve is closed after it. 2.8. Network cold water flows through a settling filter, feed pumps (one is working, the other is in reserve), a heater, cation exchange filters and enters the suction manifold of the network pumps.3. STARTING THE BOILER
3.1. Turn on the “NETWORK” toggle switch, turn off the network and sound alarms. At the same time, the “NETWORK” and “OPERATION” indicators light up and the program for monitoring the boiler status sensors starts. If the sensor parameters deviate from the norm, the corresponding indication lights up. 3.2. After supplying fuel to the boiler burner, start the start-up program by moving the “START – STOP” toggle switch to the “START” position. 3.3. The boiler is started and controlled by the KSUM-1 automation.4.BOILER OPERATION
4.1. The boiler unit operates in fully automatic mode. 4.2. Boiler automation is divided into: a) safety automation; b) automatic control. 4.3. Automatic temperature control includes: b) automatic activation of the boiler; c) automatic maintenance of network water pressure in the return pipeline; a) automatic control of the temperature of hot water in the supply pipeline within specified limits; d) automatic shutdown of the boiler. 4.4. Safety automation includes: a) emergency automation; b) automatic alarm system. 4.5. Emergency automation includes; - protection for lower air gas pressure after the fan; - protection against emergency excess of water temperature (115 °C); - contactor protection of the burner (interference in the burner). 4.6. Automatic signaling includes: a) alarm “burner malfunction”; b) gas supply system alarm; c) alarm of circulation pumps; d) alarm of injection pumps; e) alarm of the upper and lower limits of the hot water temperature of the supply pipeline; f) low temperature alarm; g) alarm of the upper and lower limits of water pressure at the entrance to the boiler. 4.7. It is necessary to check the safety valve every shift by “exploding”. 4.8. When the boiler is operating, it is necessary to monitor the pressure and temperature of the supply and return network water. 4.9. More than important parameters water and gas in the boiler room. 4.10. Operation of boilers and water heaters with faulty automation and equipment is not allowed! 4.11. When the boiler is turned off by the general boiler control device, the boiler is ignited by the operator after completing the automatic stop program.5. STOPPING THE BOILER
5.1. To stop a boiler operating in autonomous control mode, the operator must:- press the “stop” button on the front panel of the KSUM-1 unit, after which the stop program is executed automatically;
- close the tap on the burner;
- open the purge line tap;
- turn off the fan when the fan is running circuit breaker power supply on the unit and the “Network” switch on the front panel of the KSUM-1 unit. In this case, the “Network” indicator light should turn off.
- Turn off after 30 minutes. circulation pump if the other boilers in the boiler room are not working.
6.EMERGENCY STOP OF THE BOILER
6.1. An emergency stop of the boiler is carried out automatically when the emergency automatic system is triggered in the event of: - damage to the gas pipeline in the boiler room (gas contamination); - damage to the external gas pipeline to the boiler room; - destruction of the boiler; - spontaneous increase or decrease in pressure in the boiler room; - increasing the water pressure in the heating system above the permissible level; - rupture of the heating main. 6.2. If the boiler is operating in emergency mode and the emergency automation does not work, it is necessary to turn off the boiler room emergency switch. 1.4 . The installation of external water-to-water heat exchangers should be considered advisable if the quality indicators of the make-up water of the closed boiler circuit do not exceed the values given in Section.supply gas and light one of the lower burners (see paragraphs; ; and );
after the gas ignites, close the valves on the fuel oil line to the nozzle of this burner;
blow out the nozzle with a feather, slide it out of the burner and remove it.
supply fuel oil to the nozzles (one of the lower ones) and ignite it (see paragraphs. ; ; - );
close the valves on the gas pipeline in front of the burner;
make sure the torch is burning steadily;
open the burner safety spark plug valve.
submit a request for disassembly electrical diagrams electric motors of mechanisms and remote control of fittings and gates;
Perform internal inspection, cleaning and repair of the boiler only with written permission (by order) and in compliance with the relevant safety regulations;
Perform gas-hazardous work in accordance with the Safety Rules in the Gas Industry.
6.3 . When the boiler is taken out for a period of more than 30 days (summer period) before conservation of the boiler and heat exchangers, carry out an external inspection of the heat exchanger tubes in order to assess their density, for which:
turn off the heat exchangers for network water with plugs and drain them;
remove the covers from the housings of all heat exchangers;
create a circuit water pressure equal to 1.0 - 1.2 MPa (10 -12 kgf/cm 2) by turning on the NCZK and, if necessary, the NPZK, adjusting the circuit water pressure with control valve B-1;
inspect the tubes, if damaged, restore their density, and if this is not possible, plug them;
Carry out all operations to inspect heat exchanger tubes at a circuit water temperature of no higher than 45 °C.
6.4 . After installing the covers on the heat exchanger bodies, perform internal preservation of the boiler and heat exchangers by pumping make-up water from the deaerator tanks through the boiler and closed loop;
turn off the NPZK and NZK and open valves K-11 and K-12 on their bypasses;
Make-up water must be discharged through a continuous blowdown pipeline into the drainage expander and a periodic blowdown pipeline with its subsequent supply to the installation for cleaning industrial condensates or to the air intake unit;
Pump water during the entire boiler shutdown period.
6.5 . Carry out internal preservation of the boiler and heat exchangers installed in heating boiler rooms with a sodium silicate solution in accordance with current regulations. Methodical instructions on conservation of thermal power equipment.
. EMERGENCY PROVISIONS
7.1 . In case of equipment malfunctions:
carefully check the performance indicators and, based on instrument readings and external signs, form an idea of the violation of the regime;
inform the shift manager of the CTC or power plant about the incident;
establish the nature and location of the damage;
turn on backup and turn off damaged equipment;
make sure that backup equipment is working properly;
take measures to restore damaged equipment.
7.2 . In case of accidents, immediately provide medical care to the victim in accordance with the current rules.
ABOUT Organize a call for medical personnel and notify the shift manager of the CTC and the power plant about the incident.
7.3 . Register in the operational log the available data about the accident, indicating the beginning, the nature of the occurrence and the actions of personnel to eliminate it, as well as the time of individual events (turning on and off equipment, triggering interlocks, protections and alarms).
7.4 . The boiler must be immediately stopped by the protections (see paragraph. of this Standard Instruction) or directly by personnel in the case of:
failure of the circuit water flow meter, if in this case irregularities occur that require power adjustment;
stopping the NC and not turning on the backup pump via AVR;
stopping the oil pumping station and not turning on the backup pump via AVR;
increasing the pressure of the circuit water at the boiler outlet to 2.6 MPa (26 kgf/cm 2) or lowering it at the indicated temperatures to a value lower than those given in the table;
|
Circuit water pressure at the boiler outlet, MPa (kgf/cm2) |
0,6 (6,0) |
0,8 (8,0) |
1,0 (10,0) |
1,3 (13,0) |
1,6 (16,0) |
1,9 (19,0) |
P Note.The circuit water pressure must be higher than the network water pressure. The circuit water pressure values in the table are given taking into account its underheating to the saturation temperature by 30 °C.
rupture of pipes of boiler heating surfaces, collectors and pipelines at appropriate pressure;
detection of cracks, swelling, leaks or sweating in welds, leaks in the main elements of heat exchangers;
extinguishing the torch in the firebox;
unacceptable decrease in gas or fuel oil pressure behind the control valve;
turning off the smoke exhauster or blower fan;
explosion in the furnace, flue, destruction of lining, other damage threatening personnel and equipment;
fires that pose a danger to personnel, equipment and remote control circuits of shutdown valves included in the protection circuit;
increasing the temperature of the circuit water at the boiler outlet to 190° C;
loss of voltage on remote and automatic control devices or all instrumentation;
rupture of the fuel oil or gas pipeline within the boiler.
7.5 . In case of emergency shutdown of the boiler:
close valves C-1 and C-8 on the return and forward pipelines of network water and open their bypasses;
close valves K-3, K-5 and K-7 on the supply of circuit water to the heat exchangers and open their bypasses;
remove the NC switch from the AVR;
stop the NZK and close the valves on the suction side and the discharge side, close the P-2 valve on the continuous purging pipeline of the circuit;
open valve K-12 on the NC bypass;
in case of emergency shutdown of the oil refinery additionally open valve K-11 on their bypass.
7.6 . The boiler must also be stopped by order of management in the event of:
detecting fistulas in heating surfaces, collectors, pipelines, the appearance of leaks and steam in fittings and flange connections boiler, as well as in the flanges of heat exchanger housings;
malfunctions of individual protections or remote and automatic control devices, as well as instrumentation.
IN The boiler shutdown time in these cases is determined by the chief engineer of the power plant or the head of the boiler house.
. SAFETY, EXPLOSION AND FIRE PROTECTION INSTRUCTIONS
8.1 . Basic instructions on safety precautions, explosion and fire safety must be reflected in local instructions drawn up in accordance with the guidance documents listed in paragraph. of this Standard Instruction.
8.2 . Safety requirements for servicing heat exchangers are given in the installation and operation instructions issued by the heat exchanger manufacturer, on the basis of which, depending on the type of heat exchangers, local instructions are developed.
. VOLUME OF EQUIPMENT OF THE BOILER WITH MEASURING MEANS, AUTO-REGULATION, TECHNOLOGICAL PROTECTION, INTERLOCKING AND ALARMS
D To control the operation of the boiler, the following instrumentation must be installed:
recording and indicating flow meter for measuring the flow of circuit water through the boiler;
recording flow meter for measuring the flow of network water through heat exchangers;
recording flow meter for measuring the flow rate of continuous purging of a closed circuit;
indicating flow meter for measuring the flow rate of periodic boiler blowdown;
recording flow meter for measuring the flow of make-up water in the circuit;
indicating pressure gauge for measuring water pressure in front of the boiler (behind the LC valve);
recording and displaying pressure gauge for measuring water pressure behind the boiler;
indicating pressure gauge for measuring water pressure in front of the LC valve;
indicating pressure gauge for measuring water pressure in front of the make-up pump;
indicating pressure gauge for measuring the pressure of return network water;
indicating pressure gauge for measuring the pressure of circuit water in the heat exchanger housings;
indicating instruments for measuring pressure drops in network water at the inlet and outlet of each heat exchanger;
recording and indicating device for measuring the temperature of the circuit water in front of the boiler;
recording and covering device for measuring the temperature of the circuit water behind the boiler;
an indicating device for measuring the temperature of the return network water;
recording device for measuring the temperature of direct network water;
a recording device for measuring the temperature of the loop water at the inlet to each heat exchanger;
a recording device for measuring the temperature of the circuit water at the outlet of each heat exchanger;
a recording device for measuring the temperature of network water at the outlet of the output heat exchangers;
recording and indicating device for measuring gas flow;
an indicating pressure gauge for measuring gas pressure downstream of the control valve;
recording and indicating pressure gauge for measuring gas pressure in the gas pipeline to the boiler;
recording and indicating flow meter for measuring fuel oil flow to the boiler;
indicating pressure gauge for measuring fuel oil pressure downstream of the control valve;
recording and indicating pressure gauge for measuring fuel oil pressure in the fuel oil pipeline to the boiler;
indicating steam pressure pressure gauge for fuel oil spray;
recording flow meter for measuring fuel oil consumption for recirculation;
an indicating device for measuring the temperature of fuel oil in front of the burners;
recording device for measuring flue gas temperature;
indicating instruments for measuring the temperature of flue gases along the width of convective packets (via a switch);
an indicating device for measuring air pressure behind the blower fan;
recording device for measuring the temperature of bearings of draft machines;
oxygen meters (left and right);
instruments for measuring flue gas transparency (right and left);
an indicating device for measuring the vacuum at the top of the firebox.
P about the place should be established:
pressure gauges on the gas supply lines to each burner;
pressure gauges on the fuel oil supply lines to each burner;
sawing steam pressure gauges for each burner;
draft pressure meters on the central and peripheral air channels for each burner;
pressure gauge for measuring gas pressure behind the control valve;
pressure gauge for measuring fuel oil pressure downstream of the control valve.
9.2. Boiler automatic control system
WITH The system includes the following regulators:
main;
fuel;
general air;
vacuum at the top of the furnace;
circuit water pressure on the suction side of the NZK;
temperature of the circuit water in front of the boiler.
9.3. Technological protection
Z The values of the protection response time delays are determined by the manufacturer of the boiler equipment and the current instructions.
ABOUT The equipment switched off by the protections is put back into operation by the duty personnel after the causes of the triggering have been eliminated. On boilers using two types of fuel, a switch is installed to input and output protections, which has separate positions for each type of fuel.
N and when the boiler stops, protections apply when:
extinguishing the torch in the firebox;
a decrease in gas pressure behind the control valve;
reducing the fuel oil pressure behind the control valve with a time delay of up to 20 s;
turning off the smoke exhauster;
turning off the fan;
failure of the circuit water flow meter, if this results in a regime violation requiring power adjustment;
shutdown of the NC and failure to turn on the backup pump via AVR;
shutdown of the oil pumping station and failure to turn on the backup pump via AVR;
increasing the pressure of the circuit water at the boiler outlet to 2.6 MPa (26 kgf/cm 2 );
increasing the temperature of the circuit water at the boiler outlet to 190 °C.
Z Protection to reduce the underheating of circuit water to less than 30 °C is introduced if there is a device for generating a set point based on the difference between the actual temperature of the circuit water and the saturation temperature of the corresponding pressure of the circuit water at the outlet of the boiler (see table p. ) and is performed instead of low pressure protection. For previously designed boilers where such protection is not installed, protection is installed to reduce the pressure of the circuit water at the outlet of the boiler with a setting of 1.9 MPa (19 kgf/cm2) and a time delay of 10 s.
D omissions in the values of protection settings depend on the class of devices, the supply of which is determined by the design organization.
9.4. Local protections
9.4.1 . If the burner flame fails to ignite or fails, the oil nozzle or gas burner, as well as the ignition device, is turned off by closing the electrified fittings in front of the burner.
9.4.2 . If after 10 s the pilot light does not appear or goes out, it is switched off by gas and electric spark.
9.5. Locks
9.5.1 . When the smoke exhauster is turned off, the boiler is stopped, the valve on the gas supply to the igniter is closed, the electric spark, the blower fan and the DRG are turned off.
9.5.2 . When the guide vane of the smoke exhauster (fan) is fully opened and its electric motor is running at first speed, by blocking it, the electric motor switches to second speed with a time delay of up to 3 s.
9.5.3 . The electric motor of the smoke exhauster or fan does not turn on if the guide vane is not completely closed.
9.5.4 . The fan does not turn on if the smoke exhauster is not turned on.
9.5.5 . When the fan is turned off, its guide vane closes.
9.5.6 . The valve on the gas pipeline to the boiler does not open if at least one of the electric valves at each burner is not closed.