Fire water supply

Fire water supply is a set of measures to provide water to various consumers to extinguish a fire. The problem of fire water supply is one of the main ones in the field of fire fighting. Modern water supply systems are complex engineering structures and devices that provide reliable water supply to consumers. With the development of water supply to populated areas and industrial enterprises, their fire protection improves, since the design, construction, reconstruction of water pipes takes into account the provision of not only economic, industrial, but also fire-fighting needs. The main fire-fighting requirements provide for the need for the supply of standard volumes of water under a certain pressure during the estimated time of extinguishing fires.

Types of plumbing. Classification of water supply by pressure.

By designation, water pipes are divided into drinking, industrial and fire-fighting. Depending on the pressure, fire-fighting water pipes of high and low pressure are distinguished. In the high-pressure fire-fighting water supply, within 5 minutes after a fire is reported, the pressure necessary to extinguish the fire in the tallest building without the use of fire engines is created. To do this, stationary fire pumps are installed in the buildings of pumping stations or in other separate rooms.

In low-pressure water pipelines during a fire, fire pumps are used to create the required pressure, which are connected to fire hydrants using suction hoses.

In high-pressure water pipelines, water is supplied to the fire site through hose lines directly from hydrants under pressure from stationary fire pumps installed in the pumping station.

All water supply facilities are designed so that during operation they pass the estimated water flow for fire needs at the maximum water flow for household and drinking and industrial needs. In addition, in clean water tanks and water towers, an inviolable supply of water is provided for extinguishing fires, and fire pumps are installed in pumping stations of the second lift.

Pump-hose systems that are assembled when extinguishing fires are also elementary high-pressure fire-fighting water pipelines, consisting of a water supply source, a water intake (suction grid), a suction line, a combined pumping station of the first and second lift (fire pump) , water pipelines (main hose lines), water supply network (working hose lines).

Water towers are designed to regulate the pressure and flow in the water supply network. They are installed at the beginning, middle and end of the water supply network. The water tower consists of a support (trunk), a tank and a tent-device that protects the tank from cooling and freezing of water in it. The height of the tower is determined by hydraulic calculation, taking into account the terrain. Usually the height of the tower is 15...40 m.

The capacity of the tank depends on the size of the water pipeline, its purpose and can vary widely: from a few cubic meters on low-power water pipelines to tens of thousands of cubic meters on large urban and industrial water pipelines. The size of the regulating capacity is determined depending on the water consumption schedules and the operation of pumping stations. In addition, they include an untouchable fire reserve to extinguish one external and one internal fire within 10 minutes. The tank is equipped with pressure, collapsible, overflow and mud pipes. Often the discharge and collapsible pipes are combined.

A variety of water towers are water tanks, which are designed not only to regulate the pressure and flow in the water supply network, but also to store fire-fighting water for extinguishing fires for 3 hours. Reservoirs are located on elevated places.

Water tanks and towers are included in the water supply network in series and in parallel. When connected in series, all water from pumping stations passes through them. In this case, the injection and collapsible pipes are not combined, and they work separately. At a minimum water consumption, excess water is accumulated in a reservoir or in a tank, and at a maximum, this reserve is sent to the water supply network.

When connected in parallel to the water supply network, excess water enters the tanks and tanks (at minimum water consumption), and at maximum water consumption it is sent to the network. In this case, the discharge and distributing pipelines can be combined. To control the water level in tanks and reservoirs, measuring devices are provided.

According to the type of the serviced facility, water supply systems are divided into urban, rural, industrial, agricultural, railway, etc.

According to the type of natural sources used, water pipes are distinguished that take water from surface sources (rivers, reservoirs, lakes, seas) and underground (artesian, spring). There are also mixed feed water supply systems.

According to the method of water supply, there are pressure water supply systems with mechanical water supply by pumps and gravity (gravitational) ones, which are arranged in mountainous areas when the water source is located at a height that provides natural water supply to consumers.

According to the purpose, water supply systems are divided into household and drinking, satisfying the needs of the population; industrial, water-supplying technological processes of production; fire fighting and combined. The latter suit, as a rule, in settlements. From the same water pipes, water is also supplied to industrial enterprises if they consume an insignificant amount of water or, according to the conditions of the technological process of production, water of drinking quality is required.

With high water consumption, enterprises can have independent water supply systems that provide them with household, drinking, industrial and fire-fighting needs. In this case, household and fire-prevention and industrial water pipelines are usually constructed. The combination of fire water supply with household, and not with production, is explained by the fact that the industrial water supply network is usually less extensive and does not cover all the volumes of the enterprise. In addition, for some technological processes of production, water must be supplied under a strictly defined pressure, which will change when extinguishing a fire. And this can lead either to an increase in water consumption, which is not economically feasible, or to an accident in production facilities. An independent fire-fighting water supply system is usually arranged at the most fire hazardous facilities - enterprises of the petrochemical and oil refining industries, oil and petroleum products warehouses, timber exchanges, storage facilities for liquefied gases, etc.

Water supply systems can serve both one object, for example, a city or an industrial enterprise, or several objects. In the latter case, these systems are called group systems. If a water supply system serves one building or a small group of compactly located buildings from a nearby source, then it is called a local system. To supply water under the required pressure to various parts of the territory of the settlement, which has a significant difference in marks, arrange zoned water supply. A water supply system serving several large water consumers located in a certain area is called a district water supply system.

On the territory of most settlements (cities, towns) there are different categories of water consumers, presenting various requirements for the quality and quantity of water consumed. In modern urban water pipelines, the consumption of water for the technological needs of industry is on average about 40% of the total volume supplied to the water supply network. Moreover, about 84% of water is taken from surface sources and 16% from underground sources.

The water supply or design system is usually divided into two parts: external and internal. The external water supply includes all facilities for the intake, purification and distribution of water by a water-wire network before entering buildings. Internal water pipes are a set of devices that provide water from the external network and supply it to water-folding devices located in the building.

Water supply for firefighting purposes in cities is provided by fire trucks from hydrants installed on the water supply network. In small towns, additional pumps are included in the NS-I to supply water for extinguishing fires, and in large cities, fire consumption is an insignificant part of water consumption, so they practically do not affect the operation of the water supply system.

In accordance with modern standards, in settlements with a population of up to 500 people, which are located mainly in rural areas, a combined high-pressure water supply system should be installed to provide household, drinking, industrial and fire needs. However, it is not uncommon that only domestic and drinking water supply is constructed, and water is supplied for fire needs by mobile pumps from reservoirs and reservoirs replenished from the water supply.

In small settlements for economic and fire-fighting needs, local water supply systems are most often arranged with water intake from underground sources (mine wells or wells). Centrifugal and piston pumps, Airlift systems, wind power plants, etc. are used as water-lifting devices. Centrifugal pumps are the most reliable and easy to use. As for other water-lifting devices, due to their low productivity, they can only be used to replenish fire water supplies in reservoirs, reservoirs, water towers.

Sources of water supply

In accordance with the two categories of natural water sources, water intake structures are also divided into two groups: structures for receiving water from surface sources and structures for receiving groundwater. The choice of one or another source of water supply is determined by local natural conditions, sanitary and hygienic requirements for water quality, and technical and economic considerations. Wherever possible, preference should be given to underground sources of water supply.

Surface sources include rivers, lakes and, in some cases, seas. The location of the water intake is determined in such a way that the following conditions are satisfied:

the possibility of using the simplest and cheapest method of taking water from a source;

uninterrupted receipt of the required amount of water;

ensuring the supply of as clean water as possible (cleaning from pollution);

the closest location to the object supplied with water (to reduce the cost of water supply and water supply).
Groundwater occurs at various depths and in various rocks.

For water supply use:

water of confined aquifers covered from above with impermeable rocks that protect groundwater from pollution;

non-pressure groundwater with a free surface, contained in layers that do not have a waterproof roof;

spring (spring) waters, i.e., groundwater that independently comes to the surface of the earth;

mine and mine waters (more often for industrial water supply), i.e., groundwater entering the drainage facilities during the extraction of minerals.

Fire hydrant device and operating requirements in winter and summer

A hydrant with a fire column is a water intake device installed on the water supply network and designed to take water when extinguishing a fire.

When extinguishing a fire, a hydrant with a column can be used, firstly, as an external fire hydrant in the case of connecting a fire hose to supply water to a fire extinguishing site and, secondly, as a water feeder for a fire truck pump.

Depending on the design features and conditions of fire protection of protected objects, hydrants are divided into underground and aboveground.

Underground hydrants are installed in special wells, covered with a lid. The fire column is screwed onto the underground hydrant only when it is used. An overhead hydrant is located above the surface of the earth with a column fixed to it.

The fire hydrant is designed to take water from the water supply network to extinguish fires, it consists of a riser, a valve, a valve box, a stem, a threaded mounting head and a cover. If the groundwater level is high, a check valve is installed on the outlet of the valve box.

Nominal passage, mm ............................................... ...................................... 125

Rotation frequency of the rod until the valve is fully opened, rpm......

Effort when opening the hydrant, N (kg).................................................. ..............

A hydrant-column is installed on the water supply network using a fire stand without a well device. The capacity of the combined hydrant is 20 l / s.

The fire column is used to open and close the fire hydrant, as well as to connect fire hoses when taking water from the water supply network to extinguish fires. The main parts of the column are the body and the head. In the lower part of the body there is a threaded ring for connecting the column to a fire hydrant. In the upper part there is a column control and two branch pipes with connecting heads and two valves. A central key (tubular rod) with a square coupling at the bottom and a handle at the top passes through the stuffing box in the head of the column. The handle is rotated with the valves of the discharge pipes closed. With the valves open, the handwheels will fall into the field of rotation of the handle. Thus, the column has a lock that excludes the rotation of the central key when the valves of the discharge pipes are open. Remove the column from the hydrant only when the hydrant valve is closed.

Technical characteristics of the underground fire hydrant

Nominal passage, mm ............................................... ......................................

Working pressure, MPa (kgf/cm2) .............................................. .........................

Nominal passage of the connecting head, mm ..............................................

Weight, kg, not more than ............................................... ............................................

Requirements for the operation of fire hydrants in winter and summer

There are mandatory rules for the operation of fire hydrants. Improper handling of fire hydrants can lead to an accident on the water supply network, disruption of the water supply and accidents.

Preparation of fire-fighting water supply for operation in winter conditions is carried out:

 urban water supply - during the period of autumn inspection by mobile teams of AVR REVS (departments);

 object water supply - during the autumn inspection by the water supply services of the objects.

Preparation of fire water supply for operation in winter conditions includes:

 pumping out water from risers of fire hydrants of the Moscow type and plugging drain holes with wooden plugs;

 at a steady sub-zero outdoor temperature, pumping out water from the wells of hydrants filled above the level of the riser, followed by the implementation of paragraph 1;

 fire hydrants subject to flooding by ground and melt waters are taken to a special account (Appendix No. 1 "Instructions ...") by the linear sections of the REVS and district fire departments with a mandatory mark in the book of fire water supply checks, followed by control of their condition by the REVS, pumping out water from risers after thaws (if necessary) and mandatory transmission of information to district fire departments;

 filling of wells of hydrants with a special heat-insulating filler.

Requirements for the commissioning of new sources of fire water supply.

To the fire hydrants

Fire hydrants should be installed on ring water supply networks. It is allowed to install fire hydrants on dead-end lines, regardless of the water consumption for fire extinguishing, provided that their length does not exceed 200 meters.

The diameter of the water pipes on which fire hydrants are installed is determined by calculation in accordance with clause 8.46 of SNiP 2.04.02-84 "Water supply. External networks and structures", but the minimum diameter of water pipes in settlements and industrial enterprises must be at least 100 mm, in rural areas - at least 75 mm, the maximum pipe diameter should not exceed 500 mm.

Fire hydrants should be located along highways at a distance of no more than 2.5 m from the edge of the carriageway, but no closer than 5 m from the walls of buildings. It is allowed to have hydrants on the roadway. In the historical part of the city it is allowed to place fire hydrants in accordance with the requirements of clause 8.55 of VSN-89. The distance between hydrants should not exceed 150 meters.

Around the hatches of wells located in the built-up areas of off-road coatings or in the green zone, blind areas 1 m wide with a slope from the hatches should be provided, the blind areas should be 0.05 m higher than the adjacent territory; on the carriageway of streets with improved capital coatings, manhole covers must be flush with the surface of the carriageway; well hatches on water conduits laid in an undeveloped area should be 0.2 m above the ground.

There must be a free entrance to the hydrant with a width of at least 3.5 meters.

An indication plate should be installed at the location of the fire hydrant at a height of 2-2.5 m from the ground (plates on objects made in accordance with GOST 12.4.026-76 "Signal colors and safety signs" are installed directly at water sources and in the direction of movement to him). The plate should be 12x16 cm in size, red and have white inscriptions indicating:

 type of hydrant (Moscow-type hydrant is denoted by the letter M);

 diameter of the water supply network in millimeters (inches);

 the nature of the water supply network (dead-end network is indicated by the letter T in the upper left corner of the plate);

 fire hydrant number (should correspond to the number of the house on which the coordination plate is located). Recording numbers with the number "0" in front (01.02.03., etc.) means that the index plates of these fire hydrants are located on trees, metal poles or street lighting poles, without reference to house numbers;

 digital value of the distance in meters from the plate to the hydrant.

In accordance with clause 1.12. GOST 12.4.009-83 fire hydrant indicators must be illuminated by lamps or made using fluorescent or reflective coatings

Hydrants in wells are installed vertically. The axis of the installed hydrant should be located no closer than 175 mm and no further than 200 mm horizontally from the wall of the hatch neck. The distance from the top of the hydrant to the top edge of the hatch should be no more than 400 mm and no less than 150 mm. The technical condition of the fire hydrant is checked by installing a column with a mandatory start-up of water, and there should be no leakage of water in the flange connections of the hydrant.

After the commissioning of fire hydrants, an act is drawn up in 4 copies (one copy each for the fire department, fire department, REVS (department) and the organization that carried out the construction and installation work).

When accepting into operation hydrants located on the facility water supply networks, it is required to additionally test the network for water loss. After the commissioning of fire hydrants at the facility, an act of any form is drawn up in 4 copies (one for the district fire department, the second for the customer, the third for the general contractor, the fourth for the DSPT). On the basis of the act, the characteristics of the fire water supply of the object are entered into the summary sheet of the object's water supply.

To gravity wells

To take water from natural water sources with swampy banks or the impossibility of direct water intake from them, gravity (receiving) wells are arranged for fire extinguishing purposes.

Gravity wells must have dimensions in terms of at least 0.8x0.8 m. They can be made of concrete, stone and wood. The well must be equipped with two covers, the space between which is filled with insulating material for the winter period, which protects the water from freezing.

The depth of water in the well must be at least 1.5 m. The well is connected to the water source by a supply pipe, the diameter of which must be at least 200 mm. The end of the pipe entering the water source must be located at least 0.5 m above the bottom and at least 1.0 m below the low water horizon. pipe fish and various items.

There should be a free access to the gravity well, designed for the simultaneous installation of two fire trucks. At the location of the gravity well, a light or fluorescent sign with the inscription "CKN" should be installed.

To fire ponds

The need for a device and the required volume of fire-fighting reservoirs for the objects and settlements specified in note 1, clause 2.11. should be determined according to the water consumption rates for the estimated fire extinguishing time in accordance with the instructions of paragraphs 2.13.-2.17. and 2.24. SNiP 2.04.02-84.

The number of fire reservoirs must be at least two, while each reservoir must store half the volume of water for fire extinguishing (clause 9.29. SNiP 2.04.02-84).

Fire reservoirs should be placed from the condition of their service to buildings located within a radius of:

In the presence of autopumps - 200 m;

In the presence of motor pumps - 100-150 m, depending on the type of motor pump (clause 9.30. SNiP 2.04.02-84).

The distance from water bodies to buildings of 3.4 and 5 degrees of fire resistance and to open warehouses of combustible materials must be at least 30 m, to buildings of 1 and 2 degrees of fire resistance - at least 10 m (clause 9.30. SNiP 2.04.02-84).

If the direct intake of water from a fire reservoir by car pumps or motor pumps is difficult, it is necessary to provide for receiving wells with a volume of 3-5 cubic meters. meters. The diameter of the connecting pipeline should be taken from the condition of skipping the estimated water flow for external fire extinguishing, but not less than 200 mm. In front of the receiving well on the connecting pipeline, a well with a valve should be installed, the steering wheel of which must be brought out under the hatch cover. A grid should be provided on the connecting pipeline from the side of the reservoir.
Water must be drawn from each reservoir by at least two fire pumps, preferably from different sides.

Entrances with platforms for turning fire trucks, no less than 12x12 m in size, are arranged to fire reservoirs and receiving wells.

At the location of the fire reservoir, a light or fluorescent indicator should be installed with the following: the letter index PV, the digital values ​​​​of the water supply in a cubic meter. meters and the number of fire trucks that can be simultaneously installed on the site near the reservoir.

For reliable water intake from natural reservoirs with a high steepness of the slopes of the coast, as well as a significant seasonal fluctuation of water horizons, entrances (piers) are arranged that can withstand the load of fire trucks. The entrance (pier) area should be located no higher than 5 m from the level of the low water horizon (LWL) and above the high water horizon (HWL) by at least 0.7 m and equipped with a drain tray for suction hoses. The depth of water, taking into account freezing in winter, should be at least 1 m, otherwise, a foundation pit (pit) is arranged at the site of the fence. The width of the platform flooring should be at least 4.5-5 m with a slope towards the coast and have a strong side fence 0.7-0.8 m high. less than 25x25 cm.

The chiefs (deputy chiefs) of the units should leave for the technical acceptance of new or reconstructed sources of fire-fighting water supply.

Note: Acceptance of fire hydrants after completion of construction of new and reconstruction of existing fire water supply networks is carried out by the SPT TsUS UGPS (2nd shift), or in agreement with it.

Fire water inspections

Fire water supply checks are carried out:

On city water supply networks twice a year (spring - from April 1 to June 1; autumn - from July 15 to November 1) by mobile teams of emergency recovery works (AVR) of areas of operation of water supply networks (REVS) and departments of SE "Vodokanal S .-Petersburg" with the obligatory presence of a representative of the HR. To conduct an inspection by the linear section of the REVS (department) of the State Enterprise "Vodokanal of St. Petersburg", a "Schedule for the inspection of fire hydrants for the REVS (department)" is drawn up (Appendix N 14 "Instructions ..."), which is approved by the head of the REVS (department) and agreed chief (deputy chief) During the spring inspection only fire hydrants of the Leningrad type are checked, during the autumn inspection all fire hydrants are checked.

Object fire water supply twice a year (spring - from April 1 to June 1; autumn - from August 15 to November 1) by the duty guards of fire departments with the obligatory presence of a representative of the water supply service of the facility. To check the object's water supply, the departments leave, headed by the head of the guard, from 9:30 to 11:00 and after 17:00, in agreement with the senior engineer of the Duty Department of the UGPS.

When conducting inspections of fire-fighting water supply (city and facility), the following is checked:

 availability of indicators for fire hydrants, reservoirs, gravity wells, piers, entrances and correspondence of coordinates using a tape measure;

 Availability and condition of entrances to water sources;

 the presence and condition of the outer cover of hydrants, gravity wells. In winter, the cover must be cleared of ice, the presence of loose snow on it is allowed no more than 10 cm. objects of the economy (organizations, institutions);

 internal condition of the fire hydrant well, gravity well;

 the presence of water and pressure by installing a column on all hydrants with a mandatory start-up of water. During the spring inspection of city hydrants of the Leningrad type, wells swollen with mud are cleaned (if necessary), and during the autumn inspection of all city and facility hydrants;

 measures are being taken to prepare them for operation in the winter period;

 the depth of the reservoir in the place intended for lowering the fence mesh. In winter, when conducting fire-tactical exercises and exercises, pay attention to the presence and size of the hole, clearing the site for the installation of fire trucks;

 the condition of load-bearing structures and flooring, the presence of side railings, a thrust beam and a discharge chute at the fire pier;

 checking gravity wells and reservoirs by installing autopumps with water intake and start-up.

Note: during inspections, the use of socket wrenches, poles and cuttings of pipes to open hydrants and start water without installing columns is not allowed (with the exception of German-style hydrants).

Checks of fire-fighting water supply on city networks.

During the period of inspections of fire-fighting water supply on city networks, the mobile team of the AVR REVS (departments) of the State Enterprise "Vodokanal of St. Petersburg" arrives on its own transport according to the schedule at the FC, from where it follows to the place of the inspection with a representative of the FC (senior firefighter). The results of the check are entered by the senior firefighter in the fire water supply check book. If the water source is in good condition, then the date of the check and signature is put in the corresponding column, if the water source is not working, the nature of the malfunction is indicated according to the classification of defects (Appendix N 8 "Instructions ..."). On their duty days, the chiefs of the guards are personally responsible for ensuring the departure of the representative of the PC (senior fireman) as part of the mobile team of the AVR REVS (department) of the State Enterprise "Vodokanal St. Petersburg" to check the water supply according to the schedule.

Based on the results of the autumn and spring checks of fire hydrants on the city network, an act is drawn up (Appendix N 15 "Instructions ..."), which is approved by the head of the REVS (department) of the State Enterprise "Vodokanal St. Petersburg" and agreed by the head (deputy head) of the HR. The act is drawn up in three copies: one - in the REVS (department); the second - in the FC; the third - in DSPT UGPS.

Information about the malfunction of hydrants on urban networks in the area of ​​\u200b\u200bdeparture of the FC after the end of the check is transferred to the deputy head of the HPO for service (senior engineer) for the preparation of the Order of the GPN in the name of the head of the corresponding REVS (department) SE "Vodokanal of St. Petersburg". Faults in water sources detected during fire extinguishing are recorded in the inspection book and a telephone message is transmitted to the REVS (department) of the State Enterprise "Vodokanal of St. Petersburg" indicating the deadlines for elimination. In case of non-compliance with the Instructions of the State Fire Commission and telephone messages within the established time limits, those responsible for fire-fighting water supply in HIFs are obliged to apply to the heads of the REVS (departments) of the State Enterprise "Vodokanal of St. Petersburg" the rights provided for by the "Regulations on the State Fire Supervision".

The REVS (department) SE "Vodokanal of St. Petersburg" informs the FC about the elimination of malfunctions of fire hydrants in the form of a telephone message indicating the timing of their re-check. For a re-check, the mobile team of the AVR REVS (departments) of the State Enterprise "Vodokanal of St. Petersburg" leaves with a representative of the fire department (senior fireman), who records the results of eliminating defects with the date in the book of fire-fighting water supply checks and reports them to the deputy head of the fire department.

Checks of object fire-prevention water supply.

For a qualitative study and control over the state of the object fire-fighting water supply, economic objects (organizations, institutions) are assigned to the chiefs of guards by order in part for a period of half a year. Guard chiefs are personally responsible for the timely control of the state of fire water supply sources at the facilities assigned to them within the established time limits.

All defects in fire water supply sources identified at economic facilities during the inspection period are entered in the Book of Inspections. If, during the inspection, malfunctions of water sources are detected, the head of the guard draws up an administrative protocol for the guilty responsible persons, which is transferred for analysis and issuance of a decision to the inspector of the State Fire Supervision assigned to the facility. A consolidated list of water sources that have not been repaired for 3 or more months should be sent in the form of an "alarm signal" (Appendix No. 3 "Instructions ...") to the DSPT UGPS

Information about malfunctions of water sources at facilities serviced by the State Fire Supervision Service of other ministries and departments should be sent signed by the head of the HPO to departmental inspectorates.

The inspection staff of the State Fire Supervision Authority is personally responsible for monitoring the progress of troubleshooting fire water supply sources at assigned facilities.

Information from economic entities (organizations, institutions) on the performance of work to eliminate defects in water sources must be checked with access to the site, if the water source is in good condition, an appropriate entry is made in the check book and the date is set.

All information on the state of urban and facility sources of fire-fighting water supply, obtained during the period of inspections, in the course of extinguishing fires, conducting fire-tactical exercises and classes (vocational schools, PTZ), is entered in the Book of Water Supply Inspections by the senior fireman of the guard on duty during the inspection of the water source, or immediately after returning to the unit from the fire, vocational school (PTZ). When a water source malfunction is eliminated, an entry in the Book of Checks is made after a repeated (control) check of its condition by the senior fireman of the guard on duty. The book of checks of fire water supply is filled out monthly by the deputy head of the HR immediately before compiling the Operational Report on the state of fire water supply in the protected area. If the state of the water source for the current month has not changed, then the information of the previous month is entered in the corresponding column of the Book of Checks and a signature is put.

Based on the entries in the inspection book, the person responsible for fire-fighting water supply in the HR monthly up to the 25th day is:

 information about the malfunction of the fire water supply in the area of ​​​​the departure of the PCh (Appendix N 5 "Instructions ..."), which are taken out in one copy on the main vehicles;

 an operational report on the state of fire water supply in a protected area (Appendix N 2 "Instructions ..."), which is transmitted to the Duty Department of the Central Control Center of the UGPS on the 26-27-28-29 of each month on the day of duty of the second guard.

Water supply test method for water loss

Water supply networks are tested during hours of maximum water consumption, for example: in residential buildings - from 7 to 9 am; at industrial facilities in the presence of utility and drinking water supply - during the lunch break; with industrial and fire-fighting water supply - depending on the water consumption for production processes.

The method of testing water supply networks for water loss is to:

 establish the pressure and flow of water available in the water supply network;

 determine what pressure and flow rate of water should be according to the norms;

 compare the available pressure and water flow with what should be according to the standards and make a conclusion about their compliance.

Testing for water loss of low pressure water pipes.

The test for water loss of low pressure water pipes can be carried out using imported pumps in the following sequence:

The estimated fire water consumption for external fire extinguishing is determined in accordance with the requirements of SNiP 2.04.02-84 "Water supply. External networks and structures".

Determine how many autopumps will be required to select the required water flow from the external network, for example: Qnor = 90 l / s, n = 90/40 = 3 pumps of the PN-40U brand will be required for testing

Fire columns are installed on the most unfavorably located hydrants and are connected to the pump with the help of soft hoses (to prevent pumping water under vacuum and, thereby, prevent contamination of the water supply system with groundwater). Rubberized sleeves with a diameter of 66, 77 mm (one for each branch pipe) are attached to the pressure nozzles of the pump, ending with trunks with large diameter showers.

The water flow from the trunks is determined and the total water flow from the water supply system is calculated according to the table below.

Testing for water loss of high pressure water pipes.

High pressure water pipes are tested for water loss in two ways:

a) A hose line 120 m long is laid with the supply of trunks with a spray of 19 mm to the ridge of the highest building on the site. The water flow rate of each jet must be at least 5 l/sec. The total number of design jets that can be obtained during testing is determined depending on the standard fire water consumption for a given object. For example, for a given object, the calculated fire water flow is 20 l/sec, then the number of jets to be obtained during testing should be equal to n=20/5=4 jets. This number of jets can be obtained from one or two hydrants. Having fully opened the valves on the fire columns and supplied water to the hose lines, determine the pressure at the column using the pressure gauge.

Then the value of the actual water consumption is determined by the formula:

Q \u003d 0.95 Krl  (Hk - Hst), where

Krl - the number of hose lines attached to the column;

Hk - pressure on the column pressure gauge;

Nstv - the height of the trunk above ground level.

b) The hose lines indicated in the first method are laid, and the trunks are located at ground level. The test of the network is carried out at a pressure at the column, the value of which is equal to Hk=Nstv+28. Then the minimum value of the total flow from the hydrant will be equal to:

Q \u003d 0.95 Krl  (Hstv + 28)

The actual flow rate is determined by the readings of the pressure gauge at the column according to the formula:

Q = 0.95 Crl  Hc

If during the test, by supplying the calculated number of jets, it is found that QfacQnorms, then it is necessary to provide local installations for increasing the pressure.

Testing of internal water pipes for water loss.

To test the internal network, it is necessary to select the most highly located and remote from the input internal fire hydrants.

Determine the required number of jets and water consumption for internal fire extinguishing for a given building in accordance with SNiP 2.04.01-85 "Internal water supply and sewerage of buildings".

Lay non-rubberized fire hoses with trunks 10, 15 and 20 m long from the cranes. To obtain fire jets with a capacity of up to 4 l / s, fire hydrants and hoses with a diameter of 50 mm should be used, for fire jets of greater productivity - with a diameter of 66 mm.

In order not to flood the premises with water during the test, the trunks must be led out the window or door outside the building.

Internal fire water supply for water loss is tested in one of the following ways:

 changing the radius of action of the compact part of the jet. With this method, when water is supplied through the trunks, the radius of action of the fragmented (entire) jet is measured in meters. The radius of the compact part of the jet is 0.8 of the radius of the fragmented jet, i.e. Rk = 0.8 Rp. The resulting radius of action of the compact part of the jet must be compared with what should be according to the standards.

 free pressures of internal fire hydrants should ensure the receipt of compact fire jets with a height necessary to extinguish a fire in the highest and most remote part of the building. The smallest height and radius of action of the compact part of the fire jet should be taken equal to the height of the room, counting from the floor to the highest point of overlap, but not less than: 6 m - for residential buildings, as well as in public, industrial and auxiliary buildings of industrial enterprises, up to 50 m high ; 8 m - for residential buildings with a height of more than 50 m; 16 m - for public and industrial buildings of industrial enterprises with a height of more than 50 m.

Note: the test of the internal water supply for water loss should be carried out with the simultaneous supply of the calculated amount of water for external fire extinguishing.

Features of fire water supply in waterless areas

Sometimes, due to the underdeveloped system of urban water supply, there is not enough water for fire extinguishing. In these cases, the head of the first fire brigade unit that arrived at the fire must: organize the supply of fire nozzles in decisive directions, ensuring extinguishing in other areas of the fire by dismantling the structures and creating the necessary gaps; take measures to find out the location of the nearest water sources, from which additional water can be obtained by installing fire equipment to work in pumping or delivering it by tank trucks, fuel trucks, watering machines and other equipment. When extinguishing a fire by transporting water, such a number of trunks should be used, the uninterrupted operation of which would be ensured by the transported water.

Identification of urban areas not provided with water for fire extinguishing

The determination of building sites that are not provided with water for extinguishing in the area of ​​\u200b\u200bthe exit of the fire brigade should be preceded by work to determine the water yield of the water supply network for fire extinguishing in strict accordance with the regulatory requirements set forth in SNiP. When analyzing water loss to extinguish fires in water supply networks, it is necessary to carefully identify areas that do not have water supply networks, pre-built reservoirs (reservoirs), as well as natural water sources (rivers, lakes, ponds, etc.). This information should be put on the water source chart and plots (areas) raised with the necessary calculations, schemes for obtaining water (by transportation, pumping) in case of extinguishing fires on them.

Organization of water supply to the place of fire in waterless areas

The conditions for successful fire extinguishing require a constant supply of the required calculated amount of water to the fire site. Practitioners of the fire department are well aware of the importance of obtaining water in a timely manner and in the required quantity to extinguish fires, which in most cases is the main means of fighting fire.

Based on the analysis of the availability of water for firefighting, organizational and practical measures should be developed in each fire brigade garrison, in the area served by the fire department, to ensure the organization of timely and in the required amount of water supply to extinguish fires.

With a lack of water, it is very important to take timely measures to transport it from the nearest water sources, using regular fire equipment, as well as national economy equipment. In waterless areas, one should not neglect such sources of water as reservoirs with a water level below the suction height of fire equipment or the absence of reliable access roads to them. In these cases, it is necessary to organize the intake of water and its supply using hydraulic elevators, water-removing ejectors and motor pumps. One of the ways to get a large amount of water through existing water pipelines that have insufficient pressure and minimal flow is to turn on additional standby booster pumps, and in more complex fires, turn off individual sections of the water supply network to direct additional water to the fire site.

When organizing the supply of water by tank trucks, it must be borne in mind that the uninterrupted operation of the first delivered trunk in the main direction of the spread of fire and, moreover, the further introduction of additional trunks to localize and extinguish the fire depends on the clear and organized operation of tank trucks. To reduce the time when refueling tankers with water and emptying them at the fire site, it is necessary to organize a tanker refueling point at the water source, and a water consumption point at the fire site.

It is advisable to install auto pumps, motor pumps at the point of filling tankers; at the point of water consumption - tank trucks into which water is drained to ensure the constant operation of fire nozzles.

The number of tankers Nc necessary for the supply of water and ensuring the smooth operation of the trunks is determined with sufficient accuracy for practice by the formula

where is the time for tank trucks to the water source and back, min; - time of refueling tankers with water, min; - tank emptying time, min; - the number of reserve tankers (accepted depending on the availability of equipment).

The travel time to the water source and back to the place of fire is determined by the formula

where L is the distance from the fire to the water source, km; - average speed of the tank truck km/h.

The refueling time of a tank truck is determined by the formula

where is the capacity of the tank, l; - supply of the pump, which fills the tank truck (water flow from the fire column) l / min.

The emptying time of the tank is determined by the formula

where is the total productivity of the trunks supplying water to the fire, l / s.

Use of jet pumps to draw and supply water to the fire site

To take water from natural water sources that have unfavorable conditions for the access of fire trucks to them (steep or swampy banks), jet pumps - hydraulic elevators and water-removing ejectors can be used. The operation of these pumps is based on the principle of ejection, created by the energy of the working medium. The working medium for hydraulic elevators and ejectors is water supplied from pumps of fire trucks or fire motor pumps.

As the practice of extinguishing fires in areas with underdeveloped water supply shows, in the absence of access roads to sources of natural water supply or with unsatisfactory terrain, hydraulic elevators can be used to take water from open water sources at a lifting height of up to 20 m, located at a distance of up to 100 m with a water layer thickness at least 5 cm.

At present, hydraulic elevators G-600 are widely used, water-removing ejectors EV-200, which have the same purpose as G-600, are less commonly used.

The G-600 hydraulic elevator consists of a vacuum chamber and a suction grate; with the help of bolts, an elbow and a diffuser with a mixing chamber and a stand are attached to the vacuum chamber. The conical nozzle is screwed onto the elbow fitting and placed inside the vacuum chamber. To connect the pressure hoses to the hydraulic elevator, there are coupling heads at the ends of the diffuser and the elbow.

The principle of operation of the hydraulic elevator is as follows: under the pressure created by the pump, water flows to the hydraulic elevator. A jet of water emerging from the nozzle creates a vacuum in the diffuser. Under the influence of atmospheric pressure on the surface of the reservoir, water from it rushes through the grate into the vacuum chamber, then into the diffuser, where it mixes with water supplied to the hydraulic elevator.

In the practice of extinguishing fires with the adaptation of hydraulic elevators, the following schemes are most widely used.

1. Scheme of water intake by hydraulic elevator systems using suction hoses. The operation of this scheme is carried out when it is necessary to obtain significant water consumption to extinguish a fire. Water is taken from the tank truck through the suction hose by the pump, and its working part is fed through the pressure pipe and further along the pressure fire hose to the hydraulic elevator, from which, together with the ejected water, it enters the tank through the return line of the fire hoses. The ejected part of the water obtained in this way is directed through the second nozzle of the pump to extinguish the fire.

2. Scheme of water intake by hydroelevator systems using a stationary pipeline. In this case, water from the tank truck is supplied through a pipeline connecting the tank with the suction cavity of the pump. In this case, the capacity of the tank truck plays the role of an intermediate capacity that ensures the stable operation of the hydraulic elevator system.

3. Scheme of water intake by hydraulic elevator systems using a water collector. The water collector is installed on the suction pipe of the pump, and the capacity of the tanker is used only to start the system. After starting, the container is turned off and does not participate in the operation of the system. Working and ejected water enters directly into the pump.

When supplying water to the fire site, it is necessary to maintain pressure on the pump, which depends on the ejected flow rate and the height of the water rise from the source. The pressure value when working with the G-600 hydraulic elevator is taken according to the table.

To determine the possibility of bringing the hydraulic elevator system into operation, the water supply in the tanker tank (V, l) is compared with the amount of water needed to start it. This quantity is determined by the formula

where - respectively, the volumes of water in the inlet and outlet hose lines, l, determined by the formula (l - length of the hose line of the system, m; 2 - water reserve coefficient (for one hydroelevator system)).

or according to the table

Number of hydraulic elevators	Hose line diameter, mm	Length of hose lines, m
One EV-200

If the amount of water in the tank remains less than necessary, it must be replenished to the required amount. During normal operation of the hydraulic elevator, it is capable of delivering at least 600 l / min of water, which is enough to operate one barrel with a 19 mm diameter spray or two or three barrels with a 13 mm diameter spray. The uninterrupted operation of the hydraulic elevator of the system requires the entire personnel to constantly monitor the correct operation of all sections of the system and take urgent measures to eliminate the detected malfunctions.

Below are the most common malfunctions that can lead to a system shutdown and how to resolve them.

Faults

Troubleshooting

Not enough water in the tank Clogged hydraulic lift nozzle The suction grill is clogged The suction grate of the hydraulic elevator is not immersed in the reservoir Hose lines approaching the hydraulic elevator and departing from it have creases Sudden drop in engine speed Flattening of the sleeves of the hydraulic elevator system Clogging of hydraulic elevators Exceeding the maximum suction height or distance from the installation site of the autopump to the water source Gust of sleeves in the hydraulic elevator system

Fill up to the required amount Disassemble and clean the nozzle clean grate Submerge the grate in a pond Adjust sleeves to eliminate creases Maintain the desired mode of operation of the engine, excluding a decrease in speed Clean the hydraulic elevator from foreign objects Prior to the deployment of the hydraulic elevator system, it is necessary to determine the maximum distance from the installation site of the autopump to the water source and the suction height Damaged sleeves must be replaced with serviceable ones or repaired by applying clamps

The water supply to the fire site by pumping is used mainly at a significant distance from the water sources of the fire object. This is due to the fact that one pump installed on the water source is not able to create enough pressure to overcome pressure losses in the hose lines and to create working jets of fire nozzles directly at the fire site. For this reason, a pumping method is used, which consists in the fact that water from a water source to a fire site is sequentially supplied from one auto-pump to the next, and the latter in the pumping scheme supplies water directly through the working lines to extinguish the fire.

The practice of using this method of transporting water to supply it to the fire site is quite well developed and, with the clear action of fire truck crews, ensures successful extinguishing of fires that occur in areas with insufficiently developed water supply.

Depending on the terrain, the location of water sources, the amount of water supplied to extinguish a fire, the availability and performance data of the main fire engines in service with fire departments, the methods of pumping water can be different.

Transfer method from pump to pump

According to this method, from an autopump installed on a water source, water is supplied to the suction pipe of the next pump, from which water is supplied to the next pump or directly to fire hoses located in combat positions (near the fire site).

Method of pumping water using an intermediate tank

In this case, from an autopump installed on a water source, water is supplied through pressure hoses to a tank (reservoir) or to a reservoir, from which it is taken by the following autopumps and supplied to other containers or directly to fire hoses located in combat areas.

The third method of pumping water is similar to the second

The reservoir of a fire tank truck serves as an intermediate tank. Water from the autopump installed on the water source is supplied through the hose line to the tanker tank, the pump of which supplies water through the hose lines to the tank of the next tanker or to combat areas.

When preparing fire trucks for work in transfer to the personnel of the guards on duty, especially the chiefs of the guards and drivers, the following conditions must be observed:

 fire pump with the best technical characteristics (pressure, flow) should be installed on the water source;

 to ensure the synchronism of the operation of the pumps in order to avoid sudden pressure drops of individual pumps and flattening of pressure fire hoses, and, consequently, stopping the supply of water to the place of fire. In this regard, it is necessary to provide operational communication between drivers servicing autopumps in order to respond in a timely manner to changes in pressure and immediately restore the normal operation of the pump and the entire system;

 provide for a supply of fire hoses along the sections of the pumping line for quick replacement in the event of a rupture of the hoses in the working line;

 on the pumps of fire trucks, constantly maintain a pressure that ensures a stable mode of operation of the entire pump-hose system.

Using the laws of hydraulics and formulas derived taking into account its requirements, as well as local conditions, it is possible to practically calculate any pump-hose system that can be used to extinguish fires in real conditions with a sufficiently high accuracy for practice. These calculations and the choice of the most acceptable schemes for the use of pump-hose systems should be carried out in advance for each waterless section of the area where the fire brigade departs. After the completion of this work, all settlement and graphic materials are drawn up in the form of plans (cards) for extinguishing fires in each specific waterless area and are used, if necessary, when extinguishing fires that occur in these areas. In order for the personnel of fire departments to acquire the skills to bring pump-hose systems to readiness for work in fire departments, it is necessary to regularly organize and conduct training in practical techniques and actions on the ground using the main fire and special equipment provided for these purposes.

Consideration of the fire protection scheme for any object from a residential building to an industrial enterprise provides for the installation of a main and backup water supply scheme that can provide water for localization, and in the event of a large outbreak, then extinguish the fire in full.

Typical for modern conditions, fire extinguishing systems provide not only the placement of such means inside the building, but also external elements located outside the building, ready to be brought into working condition at any time.

The presence of such external fire-fighting water supply elements not only significantly increases the security of the facility, but also guarantees that the source of water for extinguishing a fire will be practically inexhaustible.

Conditions under which external fire water supply is designed

Any buildings or openly located objects, whether residential buildings or industrial or administrative buildings, require, in addition to compliance with the general fire safety rules by personnel and residents, the availability of primary fire extinguishing equipment and communications that can quickly create conditions for fire extinguishing by professional rescue teams.

And if the primary fire extinguishing means include simple and effective means for localizing only the source of fire, then in order to tame a serious fire, at least a large amount of water and the necessary technical means are required. An automobile fire truck, designed to transport 1.5-5 tons of water, and with a large flame consumes almost the entire supply for 5-6 minutes. This state of affairs requires that communications be laid nearby that can provide the necessary amount of water not only to knock down the flame, but also to finally extinguish the foci of decay.

In urban conditions, the design of such outdoor systems is carried out on the basis of urban water supply networks. The water supply in the city, which has sufficient pressure and supplies enough water to consumers, is the best option for external water supply networks.

But in small settlements, where laying a water supply network in full is unprofitable, ensuring security falls on other types of external water supply - open reservoirs, artificial reservoirs, special water reserves. For such cases, not only the ways of supply, access to such sources are designed, but the issue of staffing of special technicians is also considered, which has the specifics of application specifically for working with reservoirs or open reservoirs.

In any case, the design and construction of such outdoor water supply complexes is carried out on the basis of state rules and standards developed for almost all cases.

Outdoor fire water supply from the central city water supply

According to the current regulations, external fire water supply should be provided for in all areas with residential and industrial buildings. This approach makes it possible to provide not only a quick response, but also significantly save on construction work and materials, because a pipeline system for drinking or technical purposes can be used as the main pipeline for water supply.

City pipeline with pipes with a diameter of 100 to 600 mm is excellent for installing additional elements that provide the organization of connection points for fire hydrants. In the normal state, the pipeline is used for domestic and household needs, it supplies water to consumers, but in case of an emergency, fire columns are connected to the valves located in the caisson wells and water is supplied directly to the fires.

For buildings of old buildings and for new buildings, the laying of such communications is carried out taking into account the requirements of state standards. Usually, the laying and equipment of the entire infrastructure is provided by the city water utility, but in cases where the settlement has a private investor or is being laid by an organization, the costs are fully borne by the developer.

The technical conditions of the central water supply system, even at the design stage, should take into account the specific needs of buildings for water in case of fire. These conditions are taken into account when conducting examinations and coordinating the project with regulatory authorities. So, for settlements, changes to the project may be proposed due to the availability of special equipment or the peculiarities of the staffing of the local fire brigade. For external water supply, it is important to take into account the peculiarities of the working pressure in the water supply system.

Typically, a general purpose water line has a low or medium pressure system. This is enough to ensure the supply of water in the event of a fire. A high-pressure water supply can, if necessary, supply a large volume of water, and this condition is taken into account in the projects of external water supply for chemical enterprises, fuel complex enterprises, hazardous industries and storage bases. A large volume of water is needed, first of all, to extinguish large-scale fires, when the fire area amounts to thousands of square meters.

Outdoor fire fighting water supply from natural water sources

In addition to external fire protection networks based on a centralized water supply, systems can be created, the main source of water, in which natural reservoirs act. Typically, such options for fire protection systems are equipped in settlements with a small number of residents and low-rise buildings.

Rivers, lakes, ponds and reservoirs as the main sources of water supply for outdoor fire extinguishing systems must have the appropriate equipment:

• Water intake sites should be equipped with access roads;
• Water intake wells must necessarily have filter elements;
• The volume of water intake wells should ensure the accumulation and conservation of a sufficient amount of water;
• In winter, ice holes should be equipped.

When planning the use of open natural and artificial reservoirs as the main sources of fire water supply, the volume of water in these reservoirs must be taken into account. When calculating, the level of the minimum mark is taken; this approach makes it possible to determine the possibility of using the source to extinguish the maximum number of fires.

Special conditions for the use of external fire water supply

Special cases when open water bodies and water sources are allowed to be used are specific situations in which:

• The settlement has a small number of inhabitants, less than 5 thousand people;
• The buildings are located separately, outside the boundaries of settlements and there is no running water on these sites;
• For buildings classified according to the classification of the need for fire extinguishing water less than 10 liters per second;
• For low-rise buildings, the dimensions of which allow not to carry out fire-fighting water supply.

But as for the exceptions, it is allowed not to build an external fire-fighting water supply:

• If the number of inhabitants in the village is less than 50 people;
• Buildings outside the boundaries of settlements, with an area of ​​\u200b\u200ba fire hazardous zone up to 150 square meters;
• seasonal buildings;

Accounting for the features of the operation of external systems in different conditions

Traditionally, the winter period in most regions is not only a period of low temperatures, but also a period of a large number of fires. The possibility of using the fire equipment of the external water supply system in winter becomes critical under such conditions. Constant and strict compliance with the requirements of the conditions for working with equipment in the winter will help to avoid many problems, including ensuring the operability of the equipment.

The main requirements of these rules are:

• Permanent technical readiness of equipment for operation at low temperatures;
• Checking the technical condition and performance during the autumn preparatory period;
• Removing excess water before the onset of frost, installing plugs or plugs made of wood or plywood;
• Drainage of water above the level of the main riser;
• Sealing the walls of the caissons from the penetration of ground storm and melt water into the well;
• Carrying out measures for thermal insulation of hydrants.

If conditions permit, reservations and the creation of water supplies are mandatory for especially fire-hazardous areas, while the central water supply system provides for prompt shutdown and repair of breaks, preventing freezing of pipes and wells with fire hydrants.

When choosing an external fire water supply system, attention is also paid to such features as the water balance in the region. For systems equipped with a central water supply, the situation when there is a lack of moisture in natural reservoirs and sources in the region does not have a significant impact. The lack of water can be replenished from artesian wells, underground storages or by transferring from water from other regions. But for settlements where the main source is a reservoir suffering from dehydration, it is unlikely that it will be possible to provide reliable fire protection.

However, as practice shows, the application of a number of administrative measures will significantly increase the efficiency of response to a fire situation and thereby more effectively cope with a fire.

Such measures may include:

• Organization of saving fire equipment in the most accessible public places;
• Involvement of local activists in firefighting activities, training and training of residents in actions as part of teams of the fire brigade;
• Carrying out activities to deepen the reservoir and lay the pipeline to the most watery places;
• Involvement of local resources in the work - agricultural machinery, road filling tanks;
• Early creation of a water reserve in containers with a soft body.

Thus, when conducting a preliminary consideration of options for external fire-fighting water supply, one should, first of all, take into account the capabilities of the plumbing system itself to ensure a guaranteed supply of the required amount of water to extinguish the fire.

The second important point is the possibility of trouble-free operation of the system throughout the year, which completely eliminates the risk of freezing in the winter and drying up of the source in the dry season.

And finally, the last important factor is the economic feasibility of investing in the equipment of additional elements.

1. General concept of p / p water supply.

Fire water supply - a set of measures to provide water to various consumers to extinguish a fire. The problem of fire water supply is one of the main ones in the field of fire fighting.

2. Basic concepts of hydraulics

Fire jets. Fires are usually extinguished with water and foam jets. As firefighting practice has shown, in order to successfully eliminate combustion, water jets must have a sufficiently large impact force at the highest possible flow rate and maximum flight range.

Such jets are obtained from a nozzle consisting of conical and cylindrical parts. The conical part of the nozzle increases the output speed, while the cylindrical part maintains the shape of the jet and prevents it from splashing. The flight range of the jet from the conical nozzle is the greatest at an inclination to the horizon of 30 degrees, in this case it is 4 times higher than the maximum lifting height. To extinguish outdoor fires, the compact part of the jet must be at least 17 m.

Water hammer - a sharp increase in pressure in pipelines (fire hoses) as a result of a change in the speed of the fluid moving in them with a rapid shutdown of the flow. Water hammer is especially dangerous in long pipelines, in which significant masses of fluid move at high speeds, as it can lead to pipeline rupture. The phenomenon of water hammer is observed when a fire hose is suddenly closed or opened with a plug valve. The pressure from hydraulic shock propagates through the water pipe in the form of an elastic wave at a speed that depends on the elasticity of the liquid and the walls of the water pipe. For example, the propagation velocity of a hydraulic shock wave in steel and reinforced concrete pipes is 700-1300 m/s, in fire hoses 50-120 m/s.

The waves that have arisen at the control device propagate against the movement of the fluid flow, and when they reach the pump or the free surface of the liquid, they again move towards the control device, reducing the pressure in the water supply system that previously arose from the direct wave. After the operation of the regulating device is stopped, the water hammer phenomena are quickly extinguished due to the dissipation of energy. If the closing time of the gate valve is longer than the travel time and the return of the hydraulic shock waves, then the pressure does not reach its maximum value.

3. Norms of water consumption.

Water consumption rates for extinguishing fires in cities and towns are calculated depending on the number of inhabitants, the number of simultaneous fires and the number of storeys of the building. Cities and settlements have an extensive network of artificial fire reservoirs, as well as well-maintained entrances to natural reservoirs and sites (piers) for the installation of fire trucks.

The minimum water supply in fire reservoirs is 3 thousand m 3 per 1 km 2 of the city's development. In cities with a powerful fire-fighting water supply, the water supply in fire reservoirs can be reduced to 1.5 thousand m3 per 1 km2 of development. The estimated number of simultaneous fires at industrial and agricultural enterprises depends on the area they occupy: one fire with an area of ​​up to 150 hectares, two fires - more than 150 hectares.

When calculating the water consumption for external fire extinguishing at industrial and agricultural enterprises, the degree of fire resistance, the volume and width of the building, and the fire hazard category of production are taken into account. For example. The minimum water consumption per fire in an industrial enterprise is 10-100 l/s, in an agricultural enterprise 5-30 l/s. The duration of extinguishing a fire in a settlement or at an enterprise is at least 3 hours.

4. Fire water supply.

Fire water pipeline.

According to their purpose, water pipes are divided into household, industrial and fire-fighting ones. Depending on the pressure, fire-fighting water pipes of high and low pressure are distinguished.

In the high-pressure fire water pipeline, within 5 minutes after a fire is reported, the pressure necessary to extinguish the fire in the tallest building without the use of fire engines is created. To do this, stationary fire pumps are installed in the buildings of pumping stations or other separate premises.

In low-pressure water pipelines during a fire, fire pumps are used to create the required pressure, which are connected to fire hydrants using suction hoses. All water supply facilities are designed so that during operation they pass the estimated water flow for fire needs at the maximum water flow for household and drinking and industrial needs. In addition, an emergency supply of water is provided in clean water tanks and water towers for extinguishing fires, and fire pumps are installed in pumping stations of the second lift.

Pump-hose systems that are assembled when extinguishing fires are also elementary high-pressure fire-fighting water pipelines, consisting of a water supply source, a water intake (suction grid), a suction line, a combined pumping station of the first and second lifts (fire pump), water pipes (main hose lines ), water supply network (working hose lines) Water pipelines are designed to transport water from the pumping station of the second lift to the water supply network of a city or object. At least two water pipes are always provided so that in the event of an accident on one, at least 70% of the calculated water consumption for extinguishing fires is supplied through the second. Water pipelines are connected by jumpers with valves, with which you can turn off emergency sections.

Water towers are designed to regulate the pressure and flow in the water supply network. They are installed at the beginning, middle and end of the water supply network. The water tower consists of a support, a tank and a tent-device that protects the tank from cooling and freezing of water in it.

The height of the tower is determined by hydraulic calculation, taking into account the terrain. Usually the height of the tower is 15-40m. The capacity of the tank depends on the size of the water pipeline, its purpose and can vary widely: from a few cubic meters to low-power water pipelines to tens of thousands of cubic meters in large urban and industrial water pipelines. The size of the control tank is determined depending on the water consumption schedules and the operation of pumping stations. In addition, they include an untouchable fire reserve to extinguish one external and one internal fire within 10 minutes. The tank is equipped with discharge, collapsible, overflow and mud pipes. Often the discharge and collapsible pipes are combined.

A variety of water towers are - water tanks, which are designed not only to regulate the pressure and flow of water in the water supply network, but also to store a fire-fighting supply of water to extinguish fires for 3 hours. Tanks are located on high ground.

Water tanks and towers are included in the water supply network in series and in parallel. When connected in series, all water from pumping stations passes through them. In this case, the discharge and collapsible pipes are not combined, and they work separately. At a minimum water consumption, excess water is accumulated in a reservoir or in a tank, and at a maximum, this reserve is sent to the water supply network

5. Water supply network.

The water supply network is used for the uninterrupted transportation of water to consumers in the required quantities under pressure sufficient to supply water to the most remote and highly located point of water intake, as well as to extinguish fires.

Water supply networks are divided into ring and dead-end. In ring water supply networks, unlike dead-end ones, it is possible to turn off emergency sections of pipelines without stopping the supply of water to subsequent sections, in addition, they have less hydraulic shock. At the same time, the total length and, consequently, the cost of ring networks is much higher than that of dead-end networks.

In this regard, ring networks are usually used in urban and industrial water supply systems, and dead-end networks are used to supply small villages, livestock farms, etc. So that the water in the pipes does not freeze in winter, they are laid below the freezing depth of the soil. For example, for the middle zone of our country, the depth of laying water supply networks is 2.5 - 3 m.

6. Fire hydrant.

The fire hydrant is designed to take water from the water supply network to extinguish fires. It consists of a riser, a valve, a valve box, a stem, a threaded mounting head and a cover. If the groundwater level is high, a check valve is installed on the outlet of the valve box.

Hydrants are placed at a distance of no more than 150 m from one another in wells on fire supports. The capacity of the hydrant at a pressure loss of 0.1 MPa is 40 l / s, it maintains tightness at a network pressure of up to 1.5 MPa.

7. Fire column.

The fire column is used to open and close the fire hydrant, as well as to connect fire hoses when taking water from the water supply network to extinguish fires. The main parts of the column are the body and the head.

In the lower part of the body there is a threaded ring for connecting the column to a fire hydrant. In the upper part there is a column control and two branch pipes with connecting heads and two valves. A central key with a square sleeve at the bottom and a handle at the top passes through the stuffing box to the column head.

The handle is rotated with the valves of the discharge pipes closed. With the valves open, the handwheels will fall into the field of rotation of the handle. Thus, the column has a lock that excludes the rotation of the central key when the valves of the discharge pipes are open. Remove the column from the hydrant only when the hydrant valve is closed.

8. Rules for the operation of fire hydrants.

Improper handling of fire hydrants can lead to an accident on the water supply network, disruption of the water supply and accidents. Mandatory rules for the operation of fire hydrants have been developed. When using a hydrant, a pointer is installed next to the well during the daytime, and at night it is illuminated with the taillight of a car or a lantern. In winter, after work is completed, water is removed from the fire hydrant riser through the drain hole, and if it is closed, it is pumped out with a foam mixer.

The use of fire hydrants in winter is reported to the relevant departments of the water supply service. The technical condition of all fire hydrants is checked twice a year: before the onset of the spring-summer and autumn-winter periods - jointly by representatives of the water supply and fire services.

The test begins with an inspection of the hydrant. A column is installed on the hydrant and water is let in, water is pumped out of the riser, in the absence of check valves, the drain hole is closed. The test results are documented.

The fire department has the right to selectively check hydrants without a representative of the plumbing service with the launch of water only at positive air temperature. If the air temperature is minus (not lower than 15C), then the hydrants are inspected only externally, and at lower temperatures it is forbidden to open the covers of the wells. Hydrants with water start-up are checked only with the help of a fire column. The plumbing service dispatcher is immediately notified of malfunctions of hydrants and the elimination of defects in each fire hydrant is monitored, a sign indicating its location is posted. The cleaning of hydrant covers from snow, the acquisition, installation and monitoring of the condition of the signs are assigned to the relevant housing and maintenance organizations, enterprises, institutions and organizations on whose territory or in whose interests hydrants are installed.

The dispatcher of the service informs the fire department about repair work on the water supply network. The lid of the well is opened with a hook or crowbar. while making sure that it does not hit the thread of the hydrant riser. Since various combustible and poisonous gases can penetrate water wells, it is forbidden to smoke or use open fire when opening the cover and during operation. Firemen are not allowed to go down into the wells to check hydrants and while using them.

When installed on a fire column hydrant, the valves are closed, the column is screwed on smoothly, without effort. The column is considered fully worn if the entire thread of the hydrant riser is closed and the column is tight. When winding the column, its central key must be stationary.

To open the hydrant valve, smoothly turn the central key of the column until a characteristic noise of water appears, filling the hydrant riser and the column body. The flow of water can also be determined by the exit of the trickle from the outlet of the hydrant. After filling the hydrant and the column with water, open the hydrant valve (turn the central key of the column until it stops), and then the valves of the column pressure pipes.

9. Internal fire water supply.

The internal fire water pipeline is designed to extinguish fires, mainly in the initial stage of development. It is arranged in residential and public buildings, industrial buildings, warehouses and bases.

In high-rise and high-rise buildings, internal fire water supply usually serves as the main means of extinguishing fires on floors. The duration of extinguishing fires from internal fire hydrants is 3 hours.

The number of jets and water consumption depend on the degree of fire resistance of the buildings, the production category for fire hazard and the volume of the buildings. The main parts of the internal fire water pipeline: inlets, bypass lines at water meters, a water supply network with risers, fire hydrants. The internal fire water supply is combined with a drinking or industrial water supply. Under normal conditions, the water pressure in the fire and drinking water supply is the same.

In the event of actuation of the fire hydrant, the pressure in the fire water supply network drops, water from the utility and drinking water supply begins to flow into the fire water supply through the check valve and the liquid flow control relay. As soon as water begins to flow through the relays, they work and turn on fire pumps, as well as electric valves. Fire pumps and electric shutters can also be switched on remotely using buttons installed at fire hydrants.

10. Fire reservoirs.

In the absence or low power of the fire water pipeline, water for extinguishing fires is taken from fire reservoirs. They are natural (rivers, lakes) and artificial. Well-maintained dead-end roads are made to fire reservoirs with loopback detours at the water source or areas 12x12 m in size for the installation of fire engines and their maneuvering.

Depending on the steepness of the slopes of the coast, seasonal fluctuations in water levels, the availability of building materials, various bank protection works are carried out, receiving wells and sites for the installation of fire engines are built.

In winter, on open water sources covered with ice, ice holes are made to take water at least 0.6x0.6 m in size. A barrel without a bottom with two lids is frozen into the hole, between which heat-insulating material is laid. The location of the fire hole is marked with a sign. When constructing fire reservoirs and reservoirs, the distances between them are up to 250 m in cities and industrial enterprises and up to 150 m in rural areas. The capacity of reservoirs and reservoirs is taken from the calculation of extinguishing fires for 3 hours.

11. The procedure for organizing accounting, control and carrying out work to check the external fire water supply, as well as interaction with the services involved in its operation.

The constant readiness of fire water sources for their successful use on fires is ensured by carrying out the main preparatory measures:
quality acceptance of all water supply systems upon completion of their construction, reconstruction and repair. Joint preparation of fire water supply sources for operating conditions in spring-summer and autumn-winter periods; Periodic testing of water supply networks for water loss:
establishing a close relationship between operational water services.

In order to qualitatively check the technical condition of the SG, the following work schedule is carried out:
1. The presence of the index is checked according to GOST, the correspondence of its data to the actual one.
2. The fire column is installed on the hydrant, while the correspondence of the square on the hydrant rod with the square coupling of the fire column is revealed,
ease of connection of pressure and suction hoses and compliance with the location of the neck of the well relative to the hydrant 3. Water is released by opening the ball valve using a fire column
4. The operation of the drainage hole is checked, the SG drainage hole is closed after draining the water at the groundwater level above the flange of the fire column in order to prevent water from entering the hydrant riser (in the autumn-winter period), the mouth of the well is closed with a lid
5. The presence of an entrance with a width of at least 3.5 meters is checked
6.According to the results of checking the technical condition of fire hydrants, an act is drawn up. (Appendix 3)
7. Once a year, water supply networks are tested for water loss. Based on the test results, acts are drawn up, signed by a representative of MUP "Vodokanal" and the head of the guard
8. The guard on duty checks the steam generator during the development of operational cards (according to the schedule), and in winter under the following conditions:
10. At temperatures from - 10C to - 20C, external inspection of hydrants is allowed. Starting water is prohibited.
11. Opening well covers to inspect the hydrant at temperatures below -20C in order to avoid heat loss is prohibited.
12. In all cases, during checks, it is prohibited to use a socket wrench to open the SG
13. If, during the external inspection, defects are revealed that could serve as an obstacle to the possibility of using SG to extinguish a fire, an act is drawn up. (Appendix 4)
14 The dispatcher of the TsPPS OGPS-16 is obliged to immediately report all detected malfunctions to the operating company by fax, indicating the exact address of the faulty hydrant, the nature of the malfunction, the name of the transmitting information, the date of transmission of the information, the name of the receiving information. (Appendix 5) Control over troubleshooting is established. Suggested terms for troubleshooting are specified in Appendix No. 6. After the SG malfunction is eliminated, the operational enterprise reports to the fire department of the branch. The duty guard performs a control check of the SG troubleshooting. After checking, a note is made in the corresponding journal and these hydrants are deregistered as faulty.
15. All SG checks are carried out by guards on duty with a representative of MUP "Vodokanal" (operational service) in summer, and in winter, according to the results of external inspections, if there are comments, a representative is invited and an act is drawn up (Appendix 4).
16. When disconnecting a section of the network, no more than 5 SGs should be disconnected.
17. If it is necessary to disconnect sections of the water supply system where more than 5 SGs are installed, a representative of MUE Vodokanal is obliged to arrive at the OGPS-16 no later than 5 days before the shutdown and agree with the head of the OGPS-16.
18. Every year, the director of the branch and the director of MUP "Vodokanal" agree on the combination of work in their schedules for SG checks, water loss tests.

12. Requirements for the acceptance into operation of new sources of p / p water supply. Requirements for external networks of p / n water pipes, installation of fire hydrants.

1. The depth of the pipeline should be 0.5 m more than the calculated depth and field temperature penetration into the soil (i.e. 2.5 - 2.8 m + 0.5).

2. External fire water supply should be provided in the form of an annular circulation system with constant circulation of water in it. The device of dead-end networks is not allowed.

3. Fire hydrants should be of the Norilsk type and installed on the main sections at a distance of 100m from each other.

4. The main lines of the fire water supply should be located no further than 2.5 m from the edge of the carriageway with the provision of measures to protect fire hydrants from snow drift by arranging booths (pyramids)

5. In places where hydrants are installed, the carriageway should be made wide enough to allow vehicles to pass along the road when fire trucks are installed on the hydrant. The water supply network should be divided into repair sections by sections of valves. When one of the sections is turned off, no more than 5 hydrants should be turned off.

13. Requirements for ground, underground fire tanks designed to store fire water.

1. Ground fire tanks must be insulated with heat-insulating materials and heated water, ensuring its temperature is not lower than + 5 degrees.

2. Fire tanks must be equipped with devices for direct water intake by fire truck pumps.

3. The volume of open water bodies must be calculated taking into account the possible evaporation of water and the formation of ice. The excess of the edge of an open reservoir above the highest water level in it must be at least 0.5 m.

The number of fire tanks or reservoirs must be at least two, while each of them must store 50% of water for fire extinguishing.

14. The procedure for checking the p / n water sources, the frequency and form of reporting on the results of the check.

Checking the sources of p / n water supply is carried out by employees of guards on duty in accordance with the schedule for pre-designed routes, as well as in the course of working off, compiling, adjusting OP and OK, PTZ, PTU, extinguishing fires, eliminating accidents and natural disasters.

Checks are usually made in the afternoon according to the schedule. The time (period) of the check is agreed in advance with the person responsible for the technical condition of the water supply networks and the maintenance of the water supply sources.

The department with the head of the guard leaves for the check and checks the water sources. Based on the results of the inspection, the head of the guard on duty draws up an act (Appendix No. 2), and when checking in the winter period, an act (Appendix No. 3).

15. Checking fire reservoirs.

Fire reservoirs provide a supply of water for firefighting purposes in the absence of water supply networks.

When checking the PV, it is necessary to check:
- the presence of an index in accordance with GOST 12.4.009PZ, the correspondence of its data to the actual one;
- the presence of an entrance to the PV.

An entrance with a width of at least 4 m, a platform for turning fire trucks 12x12 in size, a hatch and ventilation should be arranged to the place of water intake from the PV. (PV must have a hatch with a size of at least 0.6x0.6 m with double covers and a ventilation pipe with a cross section of 250-300 cm2.

16. Testing of water supply networks for water loss.

The test is carried out by the head of the duty guard together with a representative of the facility (water supply service) in order to establish the possibility of taking the estimated amount of water for fire fighting needs.

Preparatory measures and practical testing of sections of water supply networks include the readiness of the necessary equipment for these purposes, theoretical training of personnel is carried out once a year and is timed to coincide with the spring-summer inspection of sources and fire water supply networks.

To test sections of low-pressure water supply networks from technical means, it is necessary to have a fire column equipped with a smooth-bore branch pipe with a diameter of 65 mm and a length of 500 mm, and a plug with a pressure gauge.

When water is supplied from a fire column, according to the pressure gauge, after 2 minutes, the water flow is determined using the table (Appendix No. 5 to the methodological recommendations for checking the p / p water supply No.

The figure shows the general scheme of the city's water supply.

1- water intake; 2 - gravity pipe; 3 - coastal well; 4 - pumps of the first lift; 5 - settling tanks; 6 - filters; 7 - spare tanks of clean water; 5 - pumps of II lift 9 - conduits; 10 - pressure-regulating structure; 11 - main pipes; 12 - distribution pipes; 13 - house inputs; 14 - consumers.

Arrangement of a water tower or other pressure and control structures it is often necessary if there is a significant unevenness in the consumption of water by the city by the hours of the day and its supply by lift pumps II.

Pressure control facilities are designed to store a supply of water to extinguish a fire.

The task of the water supply system industrial enterprise is to provide it with water for industrial, drinking and fire fighting needs.

1 - water intake structure; 2 - pumping station; 3.8 - treatment facilities; 4 - independent network; 5 - network; 6 - sewer network; 7 - workshops; 9 - village

Pumping station 2 located near the water intake 1 , supplies water for production purposes to workshops 7 over the network 5 . Waste water flows through the sewer network 6 into the same reservoir without treatment (if it is not contaminated) or, if necessary, after cleaning it in a treatment plant 8 . If it is necessary to supply water for production needs at different pressures, several groups of pumps are installed at the pumping station, feeding separate networks. Day of economic and fire-fighting needs of the village 9 and workshops of the enterprise 7 water is supplied to an independent network 4 special pumps. The water is pretreated in the treatment plant 3 .

With circulating water supply

1 - water intake; 2.5 - pumps; 3 - conduits; 4 - cooling facilities; 6.8 - pipelines; 7 - production units.

After cooling at facility 4, water is pumped by pumps 5 through pipelines 6 to production units 7. Heated water enters pipelines 8 and is discharged to cooling facilities 4 (cooling towers, spray pools, cooling ponds). The addition of fresh water from the source through the water intake 1 is carried out by pumps 2 through conduits 3. The amount of fresh water in such systems is usually an insignificant part (3-6%) of the total amount of water.

Piped and non-piped water supply, classification of external water pipes

Distinguish water supply:

• wireless
• tap water

It is based on water intake from natural or artificial fire reservoirs. To do this, sites are arranged on the shore for the placement of fire pumps, and sometimes water intake devices.

By type of serviced object By method of water supply

Pressure water pipelines are called those in which water from the source to the consumer is supplied by pumps.

Gravity flow is called, in which water from a high-lying source flows to the consumer by gravity. Such water pipelines are sometimes arranged in the mountainous regions of the country.

Rice. 3.5. Gravity water supply scheme: 1 - water intake; 2 - gravity structures; 3 - coastal well and treatment facilities; 4 - unloading well; 5 - unloading tank; 6 - plumbing; 7 - water supply network

Requirements of the technical regulation on fire safety requirements for sources of fire-fighting water supply.

SOURCES OF FIRE-FIGHTING WATER SUPPLY

Buildings, structures and structures, as well as the territories of organizations and settlements, must have sources of fire-fighting water supply to extinguish fires.

As sources of fire-fighting water supply, natural and artificial reservoirs, as well as internal and external water supply systems (including drinking, household and drinking, household and fire-fighting) can be used.

The need for the installation of artificial reservoirs, the use of natural reservoirs and the installation of fire-fighting water supply, as well as their parameters are determined by this Federal Law.

ARTICLE 68

On the territories of settlements and urban districts there should be sources of external or internal fire-fighting water supply.

The sources of external fire-fighting water supply include:

• external water supply networks with fire hydrants;
• water bodies used for firefighting purposes in accordance with the legislation of the Russian Federation

Settlements and urban districts must be equipped with fire-fighting water supply. At the same time, the fire-fighting water supply may be combined with a household-drinking or industrial water supply.

In settlements and urban districts with a population of up to 5,000 people, free-standing public buildings with a volume of up to 1,000 cubic meters, located in settlements and urban districts that do not have an annular fire-fighting water supply system, industrial buildings with facilities of categories C, D and D for fire and explosion hazard and fire hazard at a water flow rate for external fire extinguishing of 10 liters per second, in roughage warehouses with a volume of up to 1000 cubic meters, in warehouses of mineral fertilizers with a volume of up to 5000 cubic meters, in buildings of radio and television transmitting stations, buildings of refrigerators and storages of vegetables and fruits, it is allowed to provide external fire fighting sources as sources water supply natural or artificial reservoirs.

Water consumption for external fire extinguishing of one- and two-story production facilities and one-story warehouse buildings with a height of not more than 18 meters with load-bearing steel structures and enclosing structures made of profiled steel or asbestos-cement sheets with combustible or polymer insulation should be taken at 10 liters per second.

In the high-pressure water supply, stationary fire pumps must be equipped with devices that ensure that the pumps are started no later than 5 minutes after the fire signal is given.

The minimum free head in the low-pressure fire water supply network during fire fighting must be at least 10 meters.

The minimum free pressure in the high-pressure fire water supply network must provide a compact jet height of at least 20 meters with a full fire extinguishing water flow and the fire nozzle is located at the highest point of the tallest building.

The installation of fire hydrants should be provided along highways at a distance of no more than 2.5 meters from the edge of the carriageway, but not less than 5 meters from the walls of buildings, fire hydrants may be located on the carriageway. At the same time, the installation of fire hydrants on a branch from the water supply line is not allowed.

The arrangement of fire hydrants on the water supply network should ensure fire extinguishing of any building, structure, structure or part thereof served by this network from at least 2 hydrants at a water flow rate for external fire extinguishing of 15 or more liters per second, with a water flow rate of less than 15 liters per second - 1 hydrant.

REQUIREMENTS FOR SOURCES OF FIRE-FIGHTING WATER SUPPLY OF A PRODUCTION FACILITY

Production facilities must be provided with outdoor. The arrangement of fire hydrants on the water supply network should ensure fire extinguishing of any building, structure, structure or part of the building, structure, structure served by this network.

The supply of water for fire extinguishing purposes in artificial reservoirs should be determined based on the estimated water consumption for external fire extinguishing and the duration of fire extinguishing.

Fire hydrant and fire column. Their purpose, device, operation, procedure for use and operation.

A hydrant with a fire column is a water intake device installed on the water supply network and designed to take water when extinguishing a fire.

hydrant with column when extinguishing a fire can be used:

• as an external fire hydrant in case of connecting a fire hose to supply water to a fire extinguishing site
• like a fire truck pump water feeder

Depending on the design features and conditions of fire protection of protected objects, hydrants are divided into:

• underground
• elevated

Fire underground hydrant, shown in the figure, consists of three parts cast from gray cast iron: valve box 9, riser 5 and mounting head 4.

Cast iron hollow valve 12 drop-shaped, assembled from two parts, between which a rubber sealing ring 11 is installed. There are clamps in the upper part of the valve 8, which move in the longitudinal grooves of the valve box.

Spindle 7, passed through the hole in the riser cross, is screwed into a threaded sleeve in the upper part of the valve. Coupling is fixed on the other end of the spindle 6, which includes the square end of the rod 3. The upper end of the rod also ends with a square for the end key of the fire column.

By rotating the rod and the spindle (using the end key of the fire column), the hydrant valve, due to the presence of clamps, can only perform translational movement, ensuring its opening or closing.

When opening and lowering the valve, one of its latches closes the drain hole 2, located at the bottom of the valve box, preventing water from entering the hydrant well. To stop the selection of water from the water supply network, by rotating the rod and the spindle, the hydrant valve rises, while ensuring that the drain hole is opened by the latch. The water remaining after the operation of the hydrant in the riser flows through the drain hole and the drain pipe 1 into the hydrant well, from where it is removed by force.

To prevent water ingress V the hydrant body on the drain pipe is equipped with a check valve.

The column consists of a body 8, a head 1, cast from aluminum alloy AL-6, and a socket wrench 3. A bronze ring 10 with a thread for installation on a hydrant is installed in the lower part of the column body. The column head has two branch pipes with coupling heads for connecting fire hoses.

The opening and closing of the branch pipe is carried out by valves, which consist of a cover 5, a spindle 6, a poppet valve 7, a handwheel 4 and a gland packing seal.

The socket wrench is a tubular rod, in the lower part of which a square coupling 9 is fixed to rotate the hydrant rod. The socket wrench is rotated by handle 2 fixed at its upper end. The sealing of the rod exit point in the column head is provided by a stuffing box.

Installing the head on the hydrant is carried out by rotating it clockwise, and opening the hydrant and column valves, respectively, by rotating the socket wrench and handwheel.

FEATURES OF OPERATION OF FIRE HYDRANTS IN WINTER TIME.

If the air temperature is negative (not lower than -15 ° C), then the hydrants are inspected only externally, and at lower temperatures it is forbidden to open the covers of the wells. Hydrants with water start-up are checked only by the help of a fire column, since the use of socket wrenches or other devices can lead to an accident.

Literature:

2. "On approval of the Rules for labor protection in the divisions of the federal fire service of the State Fire Service" dated December 23, 2014;

3. Dmitriev V.D. The history of the development of water supply and sanitation in St. Petersburg. St. Petersburg, 2002;

4. Fire water supply: Textbook. - M .: Academy of the State Fire Service of the Ministry of Emergency Situations of Russia, 2008;

SubjectFire water supply. Purpose and arrangement of a fire hydrant and a fire column

Class type: class-group

Allotted time: 2 teaching hours.

Literature: textbook "Fire Engineering"

Expanded lesson plan.

Water supply in the system of measures ensuring fire safety

water supply system called a complex of engineering structures designed to take water from a water source, clean it, store it and supply it to places of consumption.

Purpose of fire water supply is to ensure the supply of the necessary volumes of water under the required pressure during the standard time for extinguishing a fire, subject to a sufficient degree of reliability of the operation of the entire complex of water supply facilities. The main regulatory requirements for water supply are set out in building codes and regulations. SNiP 2.04.02-84 “Water supply. External networks and structures”.

Water supply systems (water pipelines) are classified according to a number of criteria:

Reliability of water supply- They fall into three categories:

1st category of reliability- enterprises of the metallurgical, oil refining, petrochemical and chemical industries, power plants; household and drinking water supply systems of settlements with a population of more than 50,000 people - it is allowed to reduce the water supply by no more than 30% of the calculated standards for up to 3 days.

2nd category of reliability - enterprises of coal, mining, oil, machine-building and other types of industry; household and drinking water pipes of settlements with a population of up to 50,000 people and group agricultural water pipes - it is allowed to reduce the water supply by no more than 30% of the calculated standards, for up to 1 month or interruptions in the water supply for up to 5 hours.

3-th category of reliability- small industrial enterprises; agricultural land irrigation systems; household and drinking water supply systems of settlements with a population of up to 500 people - a break in the water supply is allowed for up to 1 day or a decrease in the water supply by no more than 30% of the calculated standards for up to 1 month.

By type of object served water supply systems are divided into urban, rural, industrial, agricultural, railway and others.

By type of natural sources used Distinguish between water pipes that take water from surface sources (rivers, reservoirs, lakes, seas) and underground (artesian, spring). There are also mixed feed water supply systems.

According to the method of water supply water pipelines are pressure with mechanical water supply by pumps and gravity (gravitational), which are arranged in mountainous areas when the water source is located at a height that provides natural water supply to consumers.

By appointment water supply systems are divided into household and drinking, satisfying the needs of the population; industrial, water-supplying technological processes of production; fire fighting and combined. The latter are usually arranged in the populated. From the same water pipes, water is also supplied to industrial enterprises if, according to the conditions of the technological process of production, they require water of drinking quality. With high water consumption, enterprises can have independent water supply systems that provide their household, drinking, industrial and fire-fighting needs. In this case, they usually construct household fire and industrial water pipelines. The combination of fire water supply with economic, rather than industrial, is explained by the fact that the industrial water supply network is usually less extensive and does not cover all the volumes of the enterprise. In addition, for some technological production processes, water must be supplied under a strictly defined pressure, which will change when extinguishing a fire. An independent fire water supply system is usually arranged at the most fire hazardous facilities - petrochemical, oil refining enterprises, oil and oil products warehouses, timber exchanges, liquefied gas storage facilities, etc. Fire water pipelines are of low and high pressure. In low-pressure water pipelines, the necessary pressure at the trunks is created using mobile fire pumps installed on hydrants. In high-pressure water pipelines, water is supplied to the fire site through hose lines directly from hydrants under pressure from stationary fire pumps installed in the pumping station.

Plumbing and non-piping. water supply, classification of external water pipes

In accordance with the two categories of natural water sources, water intake facilities are also divided into two groups: structures for receiving water from surface sources and structures for receiving groundwater. The choice of one or another source of water supply is determined by local natural conditions, sanatorium and hygienic requirements for water quality and technical and economic considerations. When possible, preference should be given to groundwater sources.

Surface sources are: rivers, lakes and in some cases the sea. The location of the water intake is determined in such a way that the following conditions are satisfied:

the possibility of using the simplest and cheapest method of taking water from a source;

uninterrupted receipt of the required amount of water;

ensuring the supply of as clean water as possible (cleaning from pollution);

the closest location to the supplied object (to reduce the cost of conduits and water supply).

Groundwater occurs at various depths and in various rocks.

For water supply use:

water of confined aquifers covered from above with impermeable rocks that protect groundwater from pollution;

non-pressure groundwater with a free surface, contained in layers, without a waterproof roof;

spring waters (spring waters, i.e. groundwaters that independently come to the surface of the earth);

mine and mine waters (more often for industrial water supply), i.e. groundwater entering the drainage facilities during the extraction of minerals.

Types of fire hydrants:

Moscow

Leningradsky

Rostov (Nakhichevan)