Dry pipes: the principle of operation of the fire system and scope, Portal about pipes. Fire dry pipe riser: application and inspection standards Norm for the installation of a dry pipe in residential buildings

Dry fire pipes are a fire water supply system installed for large areas where it is appropriate to keep the water supply empty for economic reasons, due to technical possibilities, or if the fire extinguishing agent can freeze, leading to rupture of pipes.

What are dry pipes of fire extinguishing systems

Dry pipe riser (ST) - a segment of a system not filled with water with a water intake point with atmospheric pressure inside equal to that of the environment. Dry-pipe water supply must be distinguished from and, which are special shut-off valves designed to contain water under pressure.

The riser does not have these purposes, although it can be equipped with a PC and valves, but more often there is a branch pipe for hoses for connecting fire equipment. It is not necessary to keep a hose near him, except when he is with a PC.

Dry (the second name is “air”) fire water supply for external or internal fire extinguishing consists of vertical and horizontal sections of pipes around the perimeter or near the protected area with supply / intake points for irrigating the zones through hoses, other technical means.

Regulations

Most of the ST issues are not regulated by the NPB. In many respects, the rules apply as for fire-fighting pipelines.

Sign (designation) of the dry pipe place

The equipment is designated by, providing in table. K.1 sign F08 for the fire ST riser: a square with a red background, with white outlines depicting a branch pipe and a half-nut (connecting head) with an arrow where the hose is connected. The color of the dry pipe is signal red.

Fire markings near the ST are mandatory, a light indicator is used in case of poor visibility. The box is recommended, but it is always installed if there is a PC. An example of design is a metal box with a lock and the possibility of sealing, on which there is an F08 sign and the word "DRY PIPE".

The device and principle of operation of the dry pipe

Work algorithm:

1. Firefighters connect the hose to the outlet fire dry pipe valve, selected as the most convenient (close to the source of fire) for extinguishing the object.
2. Start (water injection). The valve is moved away from the fire water pipeline connected to the dry pipe or a hose is fixed to its lower connecting head, supplying the fire extinguishing agent from the source:
   1. Special equipment with water (by means of pumps, a fire engine that supplies water from a tank,).
   2. Hydrant.
3. The valve is opened - OTV enters the hose.

Components:

• horizontal and vertical sections of pipes;
• risers;
• at the points of water intake / return along the perimeter of the building - quick-closing fittings (connecting heads, half nuts) less often - shut-off valves, PC.

Purpose and scope of dry pipes

Dry pipes are most in demand in large fire hazardous areas (there are indoor and outdoor versions), as they allow you to quickly (within the delay for filling the pipes) supply water in large quantities to the hoses around the entire perimeter of the protected object.

With fire-fighting dry pipes, it is not necessary to create lines of fire hoses vertically or horizontally over large areas - there is already a water supply route, it is enough to supply OTV to it. PTs require minimal maintenance, are less susceptible to corrosion, and are not constantly under pressure, since they are empty in standby mode.

Internal dry-pipe water supply is used, for example, as part of an ERW with manual start-up of shut-off valves, and external air lines. Objects:

• production, industrial;
• reactor, cable, transformer;
• public;
• engineering;
• for construction openings, where it is advisable to implement water curtains specifically ST;
• as a ready-made highway from reservoirs, reservoirs - it is enough to supply water with pumps;
• access to monitor towers;
• metro stations, railway transport facilities;
• as backup water supply;
• instead of ERW from PC.

Directly prescribed:

1. in multi-storey residential buildings from 36 to 50 m or up to 75 m with a PC in cabinets on each floor;
2. for multifunctional buildings up to 50 m with PC (libraries, administrative buildings, hotels, hospitals);
3. with shut-off valves and stair spaces in two-story buildings of the V st. resistance to fire with 4 or more apartments;
4. clause 5.2.20 of code 113.13330 - looped equipment with check valves and connecting heads;
5. SP 54.13330 (act canceled in part):
   • clause 7.4.4, in the MKD up to 50 m with outlet to the outside, with shut-off valves, half nuts, at a height of 0.8 - 1.2 m;
   • clause 7.3.13 - for saunas and baths, perforated equipment or with drenchers.

In private homes, a fire-fighting dry pipe is certainly effective, but is used less frequently. ST is appropriate if there are large areas and sources with a significant amount of water, and also if the owner is satisfied with the distribution of the water conduit throughout the premises.

Types of dry pipe systems

Dry pipe means:

1. unfilled wiring or areas of deluge/sprinkler installations. Strictly speaking, this is simply an AUPT with the possibility of keeping dry. Similarly, CT can be called any empty pipe;
2. it is ST with risers as a self-sufficient stationary equipment for supplying water, at one point of which it is pumped (from the ERW, pump, hydrant), and taken from the other, including drenchers, sprinklers. This is the source for AUPT.

More often, a fire-fighting dry pipe is an independent fire extinguishing tool. Separately, it is necessary to highlight the possibility of creating more self-sufficient equipment by perforating pipes.

sprinkler

has a wiring with sprinklers, autonomously triggered by the destruction of explosive locks-flasks with chemicals that expand at certain temperatures.

As a rule, in the sprinkler circuit, the pressurized extinguishing agent always circulates - when the sprinkler is triggered, the water begins to spray. But if it is a dry pipe, then it is filled only for a certain period, for example, during the production process. It is also often called the wiring directly next to the atomizers, if it is empty.

Deluge

initially dry-pipe in nature, since the filling of the water supply occurs at the time of extinguishing the fire. Sprinklers are open, they work all at once, and not only in the fire zone, like sprinklers. The nozzle at the exit point of the fuel outlet is not blocked, so the equipment is in a dry state, otherwise water would flow out constantly.

Requirements for dry pipe systems

The requirements for pressure, water flow, number of nozzles, line arrangement (loopback or not) are the same as for water supply and are prescribed in SP 8.13130, 10.13130. For AUPT, the norms of SP 5.13130 ​​are applied.

Norms for (SP 54.13330):

1. perforated pipes or deluge systems;
2. steam rooms brought outside the borders and connected there to the ERW;
3. the diameter of the riser is designed for a capacity of 0.006 l/s per 1 m² at a spray angle of 20 - 30 to the surface of the room's partitions. The same standards for perforated ST with a hole diameter of 2 - 3 mm in increments of 15 - 20 cm;
4. plumbing is painted red.

Norms of installation of fire-fighting dry pipes

Most of the requirements are unified with the PC:

1. pipe diameter 50 - 80 mm. For public buildings - from 65 mm, for high-rise buildings and in buildings of class. F5.1 - F5.3 (production) - from 80 mm;
2. on the riser DN 80 on each landing of the floor or on the balcony there must be one or two fire dampers;
3. dry pipes in non-smokeable stair spaces are permissible only if there is a technical justification and agreement with the State Fire Service;
4. the nozzles of each riser are equipped with connecting half-nuts or shut-off valves 40, 50, 65 mm, which are sometimes mandatory (for example, on the infrastructure of railway transport according to);
5. mounting height from the floor:
   • 1.35 m;
   • for paired branch pipes: for the first - 1 m, for the second - 1.50 m (tolerance ± 0.15 m);
6. the location of the fire-fighting ST - along the perimeter of the premises, under the ceiling, above the openings; it is allowed to pass through the corridor, staircase spaces, loggias, balconies;
7. fastening of the dry pipe is carried out with metal brackets and clamps;
8. the number of nozzles and their diameter depends on the flow rate of the fire extinguishing agent (tables N 1 SP 10.13130 ​​and 8.13130);
9. allowed;
10. material with protection of the inner surface of the pipeline from corrosion: standard steel, sometimes cast iron, if there is a technical justification - fire-resistant plastic;
11. piping arrangement:
    • ends, facades of buildings (as a rule, the rear);
    • roofs;
    • convenient places for fire escapes (staircases, interfloor) spaces.

Rules for the use and operation of a dry pipe

The fire-fighting dry pipe is suitable for objects with temperatures below -5°C. Pipes require less maintenance as they are almost always empty.

Main application rules:

1. monitor the serviceability, tightness of shutoff valves and half nuts, especially when the line is part of a fire-fighting internal or external water supply;
2. control the pressure during the extinguishing process;
3. connecting heads are closed with plugs.

Checking (testing) dry pipe risers

According to clause 55 of the PPR (Decree N 390), dry pipes are checked at least 2 times a year: in autumn and spring. The procedure includes the creation of hydraulic loads, the results are recorded in the test report.

The arrangement of the fire extinguishing system involves the installation of special equipment. Among the actively used systems, dry pipe is considered the most effective. Its key element is a dry pipe - a pipeline located along the perimeter of the room and filled with a fire extinguishing agent. What is a fire dry pipe, what are the features of the system and in what areas it is most widely used, we will consider below.

Scope of application

Installations with dry pipe working systems are indispensable at facilities where the risk of fire is increased.

They are required to be installed:

• in reactor and cable rooms;
• when installing transformers;
• at timber processing and pulp mills;
• at enterprises producing household chemicals;
• when arranging monitor towers;
• in paint and varnish industries;
• in the arrangement of sports complexes and cultural institutions;
• on stairwells of buildings with the V degree of fire resistance.

An integral element is the dry pipe in the arrangement of Finnish baths.

In small rooms, when the temperature rises, combustible gases accumulate. And the ignition process can begin even without oxygen.

To prevent a fire and even an explosion that can occur when the door is opened, you must first reduce the temperature and only then proceed to the next steps. This task is performed by a dry pipe for a sauna.

The system, which is put into operation, by spraying water on the walls and ceiling, cools the sauna, allowing you to freely enter it and complete the extinguishing.

A properly designed and installed dry pipe is able to effectively cope with a fire of any complexity.

Advantages of dry pipes

Extinguishing fires using a dry pipe system is based on a sharp cooling of the combustion zones. The main advantages of the system are:

• Ease of installation and unpretentiousness in operation. Repair of individual components will not affect the performance of the installation.
• Due to the use of dry pipes, the working part of the system can be installed in unheated rooms and operated at temperatures below 0°C.
• Affordable cost, both executive units and main components.
• High efficiency of fire extinguishing, which is achieved due to prompt response to the source of ignition.

The irrigation zone of the dry pipe system covers the entire area, thereby preventing not only the spread of fire, but combustion products.

Design features

The name of the installation speaks for itself. Its working part is made of pipes not filled with water. According to fire safety requirements, the pipe diameter of the installation for public buildings should be 65 mm, and for high-rise buildings - 80 mm.

The dry pipe is installed along the perimeter of the rooms, placing it above the door and window openings.

The dry-pipe fire riser consists of a vertical pipeline equipped with fire dampers located on all floors of the building.

The number of locking devices is determined by the length of the pipeline and the area of ​​\u200b\u200bthe room. The material for the manufacture of pipes of a fire-fighting installation is steel with an internal anti-corrosion coating.

The lower end of the fire dry pipe is connected through an external valve to a water supply system equipped with a pump or a water tank. In case of fire, a fire hose is connected through the connection head at a height of 1.35 m, through which water flows from a hydrant or fire truck.

Deployment using dry pipes makes it possible to carry out extinguishing in two directions: inside the burning room and protecting neighboring rooms from the spread of fire.

Types of dry pipe installations

There are two types of dry pipe fire extinguishing system: deluge and sprinkler.

Deluge systems

The system got its name due to the use of drenchers - special spray nozzles located in the network of irrigation pipelines.

Depending on the shape of the spray nozzle, they can be used for extinguishing with foam or water mist.

Irrigation heads may have a reflective plane that allows the formation of a jet of finely dispersed water. Such a constructive solution allows reducing water consumption during fire extinguishing and minimizing the destructive effect of moisture on material assets located in the room.

Despite the variety of design options, drenchers are united by the fact that they do not have a thermal lock.

The deluge dry-pipe installation is launched by the fire alarm system built into it, which reacts to temperature rise, smoke and fire detectors. After the alarm is triggered, sprayed water jets, forming water curtains using a fire extinguishing mixture, isolate the burning room, preventing the spread of toxic combustion products.

When arranging a dry pipe, you can change one of three options for the incentive mechanism:

• Electrical - in the event of an abnormality, the fire alarm transmits a primary impulse, activating the water supply.
• Rope - is set in motion due to a cable stretched in the zone of probable fire, equipped with fusible locks. In the event of a line break, the electric drive opens the valve to allow water to enter.
• Hydraulic - thermal lock opens under the influence of high temperatures. The pressure drop in the system is a signal for water supply.

sprinkler devices

The principle of operation of a sprinkler dry pipe system is similar to how deluge installations work.

The only difference between the systems is that in sprinkler installations there is gas in the incentive pipeline.

The main advantage of a sprinkler system is that it only supplies water to the fire area. But in comparison with deluge installations, its response time to fire is a little longer.

Irrigation nozzles used in the arrangement of the sprinkler system are equipped with fuses that prevent the gas in the pipe cavity from bleed.

The role of the actuator of this type of dry pipe system is performed by a water alarm valve. When ignited, the fusible lock is destroyed by the temperature, and sprinklers located in the fire area release the gas. As soon as the pressure in the pipeline reaches a critical value, the valve opens the water supply.

Using a dry pipe, correctly calculating the fire extinguishing system and correctly installing it, it is possible to ensure a high level of reliability of fire protection.

Source: http://trubsovet.ru/nazn/primenenie/pozharnyj-suxotrub.html

Dry pipes: norms, requirements and testing

Dry pipe - what is it? In SP 8.13130.

2009 on requirements for sources of outdoor fire fighting water supply given a clear definition of a riser-dry pipe- this is a pipeline under atmospheric pressure of the environment and not filled with a fire extinguishing agent.

And fire connecting heads, which are an integral part of a fire dry pipe, often called half-nuts for their design, are called quick-closing fittings connecting fire pumps, other equipment, and fire hoses with trunks.

Dry pipe in the tank farm at the Omsk Refinery

Street fire dry pipes, as an external fire water supply of buildings, supplying water to the roof, roof, coating, are mounted on the ends, on the facade of the building from the back - in an industrial building, in a public, engineering structure, in a residential building.

How dry pipe works

How a dry pipe works, and how fire equipment is connected to it by units of the Ministry of Emergency Situations of Russia and other fire departments:

1. Upon arrival at the fire site, a fire hose is connected to the lower connecting head of the dry pipe to supply water or foam from a fire truck (fire hydrant).
2. On fire escapes or on external stationary evacuation ladders of a building or structure, firefighters with hose rolls climb to the roof (roof).
3. After getting up, having orientated themselves with the location of the fire and assessing the current situation, they choose the shut-off fire valve located as close as possible to the place of combustion, and at the same time located in a safe place on the upper piping of the dry pipe of the building.
4. Then firefighters connect a sleeve to it, which is connected to a manual barrel, open the shut-off valve, and begin to localize and eliminate the fire.

The reverse process is also simple - a closed valve on a dry pipe, disconnecting fire hoses from a shut-off valve on the roof of the building, lowering them down.

Dry pipe connection head

There are also “dry pipes” inside buildings, as a kind of internal fire water supply, activated by manual start:

• Perforated pipeline or deluge sprinkler on the "dry pipe" in the sauna (bath, steam room).
• Fire extinguishing system with water curtains of building openings, which, due to the specifics of production, the technological process, cannot / is not practical to protect with fire gates, doors, curtains.
• For internal fire extinguishing of any other premises that are dangerous in terms of the possibility of a fire, in such a simple way to extinguish fires; including those with a fire and explosion hazard category.
• A pipeline is a “dry pipe” for water bodies, which allows you to quickly, without laying hose lines, supply water from a fire tank, reservoir, pier using a fire motor pump or a fire truck.

Perforated pipeline - "dry pipe" in the sauna

In order for the fire departments to arrive at the fire site, they can quickly find each dry pipe mounted on the end, rear facade of the building, a sign “Fire dry pipe riser” is installed on it, as an indication of the location of such fire extinguishing equipment, shown in table K .1 GOST R 12.4.026-2015 with code F 08.

Sign “Fire dry pipe riser”

It should be noted that fire dry pipes are often mistakenly called the components of stationary fire extinguishing systems - sections of distributing pipelines of water fire extinguishing installations with deluge sprinklers that are not filled with water; air/gas filled pipelines with sprinklers; as well as conduits mounted on fire articulated lifts equipped with fire monitors.

Norms and requirements for dry pipes

Given that such fire extinguishing equipment unequivocally refers to the external, internal fire-fighting water supply of buildings, it would seem, respectively, that the norms, rules, requirements for its location outside, inside the protected objects should be set out in two fundamental regulatory documents:

The first normative document gives only a definition of a dry pipe, without commenting on its application; and the second only states that in enclosed spaces that are not heated during the cold period, it is permissible to carry out piping of the internal fire water supply, outside the pumping station premises, with dry pipes, placing shutoff valves only in those premises that have constant heating.

Against the background of such “comprehensive” information, the question arises - how to design dry pipes, if the system of dry pipes, which has been implemented in practice for decades, does not seem to exist from the point of view of regulatory documentation; therefore, there are no requirements for it.

In the event of a fire in the lower and middle zones of the ZPE (up to the 8th-9th floors), it is not difficult to apply extinguishing agents, but there are complex tasks for organizing and conducting rescue operations. In this case, the RTP supplies extinguishing agents directly from fire trucks, and the fire is extinguished as in ordinary residential, administrative and public buildings. With a sufficient number of forces and means, the RTP, simultaneously with the rescue operations, must ensure the introduction of trunks into the fire and from the side of the escape routes, which makes it possible to reduce the temperature and smoke density in the building along the escape routes.

In the event of fires in the upper zone of the FIE, especially within the last floors, fire departments face difficult tasks both in carrying out rescue operations from the burning and higher floors, and in supplying extinguishing agents.

When extinguishing a fire in the upper zone, the RTP must use an internal fire-fighting water supply system with the simultaneous deployment of mobile equipment. To ensure the required pressure in the internal water supply, fire pumps are turned on. If the fire pumps did not turn on automatically when water was supplied from the internal fire hydrant, they can be turned on using the buttons installed in the fire hydrant cabinets and from the control panel located in the premises of the pumping station or central point. As a rule, the premises of pumping stations are located near the entrance to the building or near the evacuation staircase.

All hose lines are fixed with hose delays at the rate of one delay per sleeve, and from the ninth floor and above - two delays per sleeve. For quick delivery of the necessary fire fighting equipment, a special trailer is used, on which a lightweight MP-800 motor pump, an elastic portable container with a volume of 1.5 m3, special knapsacks, which are equipped with 51 mm sleeves, rescue ropes, carabiners, sleeve delays, transitional connecting heads and trunks, self-rescuers, life belts.

For mechanized laying of trunk lines to heights, ladders are used, equipped with compartments in which there are sleeves with a diameter of 66 mm. The mechanized laying of sleeves is carried out simultaneously with the extension of the ladder.

When extinguishing a fire in the PPE, various fire extinguishing agents can be used: water, foam, wetting solutions, powder. Water is the most commonly used extinguishing agent because:

• ? the use of inert gases for extinguishing is impractical due to the fact that the gas through the ventilation systems leaves the volume to be filled;
• ? the use of foams of any multiplicity does not give the desired results due to the large volume of the floor and the complex configuration.

The use of water, along with a positive effect (speed of delivery, jet range, maneuverability of water shafts, etc.), also has negative aspects: the use of non-overlapping shafts, shafts with large diameter nozzles, the work of the barrel operator “through smoke” leads to spillage of floors, damage to furniture and equipment, increasing the load on the floors. When extinguishing a fire in the fire zone, it is advisable to use water in the form of sprayed and compact jets with a small flow rate as the main fire extinguishing agent. The main types of barrels used in extinguishing fires are: spray barrels, RS-50 barrels, SK-4 combined barrels and barrels with nozzles.

The peculiarity of extinguishing fires in high-rise buildings lies in the difficulty of carrying out work on the evacuation of people and the difficulty of supplying water to high altitudes.

For the supply of fire extinguishing agents are used:

• ? internal fire water supply;
• ? dry pipes with the ability to connect fire trucks to them;
• ? hose lines from fire trucks;
• ? intermediate containers;
• ? knapsack fire extinguishing installations;
• ? fire extinguishers.

Equipping the ZPE with a fire-fighting water supply system makes it possible to extinguish fires from internal fire hydrants on an area of ​​100x150 m2, with a supply rate of up to 0.1 l / (s m2).

However, the internal fire water supply does not always provide the required water flow and fire extinguishing.

The use of dry pipes makes it possible to supply water from stationary and mobile pumping units at a working pressure of up to 2.0 MPa. In some fire departments, on the basis of the ASV-2 apparatus, knapsack fire extinguishing installations were made: RUPT-1 weighing 22 kg and RUPT-2 weighing 13.5 kg.

The RUPT-1 installation has 2 compressed air cylinders for the operation of an insulating gas mask and an OVP-10 foam fire extinguisher. The 165 fire extinguisher is equipped with a hose, at the end of which there is a barrel with a locking device, which makes it possible to economically consume the fire extinguishing composition (water with foam concentrate). The fire extinguishing area using this installation is 4-6 m2, the jet range is 3-5 m, the operating time of ASV-2 is 45 s, and ORP-10 is 53 s.

The RUPT-2 installation consists of one cylinder with compressed air and the same cylinder, recycled for a powder fire extinguisher. In this case, the operating time of the ASV-2 is 20 s, and the operating time of the powder fire extinguisher is 4-5 s.

On rapid response fire trucks, portable fire extinguishers are removed and used to extinguish fires in the initial stages of development. As a means of primary fire extinguishing, hand-held fire extinguishers are used by the population and members of the DPD.

To extinguish the developed fires in the ZPE, it is often necessary to apply several dozen trunks. However, the performance of fire pumps installed in the building does not exceed 40 l/s. In many PEPs, especially for public purposes, the internal fire fighting pipeline has external connections for connecting fire pumps. In order to save time on laying main and working lines and increase the water yield of the internal fire water pipeline, it is necessary to organize the supply of water to it through external pipes from auto pumps, tank trucks installed on fire hydrants of the city water supply network.

The power supply of fire fighting systems (pumps, fans and smoke dampers of the smoke control system, fire and passenger elevators, emergency lighting of stairwells, etc.) is not always carried out from a separate electrical panel. Therefore, it is necessary to switch off the power lines selectively, depending on the situation that has developed on the fire.

It is especially dangerous to turn off passenger and freight elevators before checking the cabins and evacuating all people from them.

Premature or unauthorized RTP shutdown of the power supply of elevators often leads to the death of people in blocked cabins.

The significant height of the PIE creates great difficulties and difficulties in

the supply of fire extinguishing agents to the upper floors, which entails an increase in the time for extinguishing a fire. The time spent on laying work lines and water supply depends on the design and planning solution of the building, the place of the fire, the distance from the ground, the method of laying the hose lines and the preparedness of the personnel. The supply of extinguishing agents to the source of combustion, the use of rational methods for laying hose lines should be worked out in fire-tactical exercises.

Hose lines are lifted using rescue ropes from balconies, loggias and through window openings. At the same time, the personnel of the unit with insulating devices and rescue ropes rise to a burning or lower floor and lower one end of the rope to the ground, and then use the rope to raise the hose line to the floor.

The next deployment technique is the laying of trunk lines along the flights of staircases. It takes a lot of time, and in some cases, the implementation of the deployment interferes with the evacuation of people.

Lifting of hose lines to the floors is often carried out using ladders and articulated lifts. Given that the lifting height of ladders and articulated lifts is limited, it is advisable to use them in combination with manual fire escapes (especially with assault ones). Significantly reduces the deployment time of units when using elevators and ladders.

To reduce the time for deployment in case of developed fires on the 10th floor and above, it is advisable to supply water through main lines with a diameter of 66.77 mm with the installation of a three-way branching on the floor or two floors below the fire. The second discharge pipe of the pump must be left free or a branching should be installed at ground level on each main line to drain water after the end of the work of the trunks or the rupture of the sleeves. During a fire on the 16th floor and above and in the presence of two or more compartments, water is pumped by placing one fire truck on the nearest hydrant (reservoir), and the second - directly at the burning building. With this scheme, it is possible to supply water from one trunk of the RS-50 to a height of about 90 m using ordinary fire hoses using a high-pressure pump.

At present, the design and construction of buildings with a height of 100 m or more is being carried out, which obliges the fire brigade garrisons to look for new effective methods and ways of extinguishing fires in them in the event of a failure in the operation of the internal fire water supply. In a number of garrisons, water supply to the heights is successfully practiced by ordinary fire trucks. To do this, the car is installed on a water source and water is supplied in the above way to an intermediate tank specially made and exported by car, installed on the 10th-15th floor of the ZPE. For the intermediate pump, a portable motor pump is used that provides water supply to the outlets, or another similar container installed on the 20-25th floor of the building.

If it is necessary to supply water to a greater height, several more intermediate tanks can be installed. Intermediate containers can be made from a special fabric. The capacity is 2-3 m3, its rigidity is ensured by an easily collapsible metal frame. Portable motor pumps and intermediate containers are taken out on sleeve cars.

The dry pipe fire extinguishing system is one of the most effective and widespread AFS (automatic fire extinguishing installation). Such structures include drencher installations. Many dry-pipe sprinkler systems have been developed, which indicates a high demand for AFS with such technical and operational characteristics. This is due to a whole list of advantages of dry pipe fire extinguishing systems.

Advantages and disadvantages

• The main advantage of the dry pipe system is the ease of installation, which guarantees reliability and simplicity in operation and maintenance;
• Availability and relatively low cost of the main components and executive units, ease of installation;
• Due to its main feature - dry pipes, the working part of the system can be mounted in unheated rooms and operated at low temperatures;
• , which is expressed not only in prompt response and effective impact directly on the source of fire, but also in the creation of an irrigation zone throughout the controlled area. This prevents the spread of not only fire, but also combustion products - smoke, toxic gases, soot, a critical temperature rise.

The main disadvantages of dry pipe AUP include:

• Unreasonably excessive consumption of water or foam;
• High irrigation intensity, which leads to an increase in the cost of restoring water-damaged premises and damaged property.

Varieties and principle of operation

Dry pipe systems can include both deluge and special designs.

Deluge installations

A special feature is the use of special spray nozzles - drenchers in the network of irrigation pipelines.

They can have a different shape and be designed to extinguish with water or foam, but they all have one thing in common - the absence of a thermal lock. Nothing prevents the passage of the water flow from the pipeline into the fire extinguishing zone. The initiation of the process of eliminating the source of fire is undertaken by the built-in fire alarm system, smoke, fire, and temperature detectors. Open sprinkler heads can be mounted vertically or at an angle or have a reflective plane that forms a jet of fine water, turning its shape from a dome to a plane. This effect has found its way into water curtains, which are widely used to prevent the spread of fire.

Elements of fire extinguishing systems are mounted above door, window or open arched openings. After actuation, jets of finely dispersed water of a special shape isolate the burning room, keeping smoke and toxic combustion products in it, at the same time, such curtains do not prevent the evacuation of personnel, like airlocks in gas installations.

The principle of operation of a dry pipe fire extinguishing system depends on the type of motive mechanism of such an installation. There are several most common types:

The dry pipe sprinkler system operates on the same principle. But there is compressed gas in the incentive pipeline. This significantly expands the scope of installations.

sprinkler installations

Irrigation nozzles have fusible fuses that prevent the bleeding of gas that fills the working pipeline of the dry pipe system. The main actuator of a dry-pipe sprinkler fire extinguishing system is a dry-pipe water alarm valve:

• The valve and its piping are designed in such a way that a small pressure in the working pipeline allows you to contain a higher water pressure in the transport one. After ignition, the temperature fusible lock is destroyed and several sprinklers in the fire zone begin to bleed air or inert gas. When the pressure reaches a critical value, the dry pipe valve releases the water supply.
• Such an installation combines the advantages of sprinkler and deluge systems. Firstly, the supply of water or foam is carried out exclusively in the fire zone. Outside of it, the surviving sprinklers block the flow of OM. Secondly, such an installation can be operated at negative temperatures.

There are some drawbacks - the response time to a fire has increased significantly.

Application area

The most common installations with dry-pipe working systems are at facilities with an increased risk of fires, which have large areas or large rooms of complex configuration. Such installations, after being triggered, begin to irrigate the entire controlled area, preventing the spread of fire. Activation can be automatic on a fire alarm or manually from a remote or central control panel.

Competent design and placement of working pipelines allows you to effectively extinguish a fire of any complexity. Installations do not require complex systematic maintenance. Repair of individual components cannot affect the performance of the installation as a whole.

Modern dry-pipe systems are equipped with open nozzles for finely dispersed water spraying, which not only reduces the consumption of fire extinguishing agents, but also minimizes the damage from the influence of water on the premises and the material values ​​located there. At the same time, the efficiency of work and the speed of eliminating the source of ignition does not decrease.

The main executive elements of the system

1. deluge valve
2. Central shut-off valve;
3. Bypass valve for filling the membrane chamber;
4. Control panel for manual start of the system;
5. Shut-off valve (automatically triggered by pressure changes in the membrane chamber);
6. Drain valve;
7. Pressure detector with signaling device;
8. Siren with hydraulic drive;
9. Installation control controller;
10. Opening deluge sprinklers;
11. Smoke detectors of the fire alarm system;
12. Solenoid actuating valve - electric start of the unit.

- this is a collective name under which various AUPs are combined. But all of them have a common feature - the working pipeline of such installations is not filled with water, which makes it possible to use the installations at low temperatures.

Equipping the premises with fire-fighting systems requires the installation of additional and special equipment. One of the types of special systems is a dry pipe - an empty pipeline mounted around the perimeter of a room and under the influence of atmospheric pressure.

Functions and device dry pipe

The complex of dry pipelines is an obligatory element of stationary fire extinguishing installations mounted in transformer boxes, cable rooms and reactors.

Structurally, a dry pipe is a system of horizontal pipes on which deluge or sprinkler sprayers and locking mechanisms are placed. Vertical pipelines are connected to the valves, which supply water to the sprinklers from tanks or other sources. Thus, when a fire occurs, the entire area of ​​\u200b\u200bthe room is filled with a fire extinguishing agent and the flame is quickly suppressed.

Most often, dry pipes are mounted under the ceiling. In the event of a fire, the taps on the sprayers open and water begins to flow. The number of nozzles depends on the size of the room and the length of the dry piping.

A fire hose can be connected to a special head of a dry pipe, brought out to the outside of the building, and the fire can be extinguished from a hydrant or fire engine.

Scope of outdoor dry pipe

Dry piping is an effective and affordable means of fighting fire. Therefore, the scope of its application is quite wide:

• Metro stations;
• car parking;
• residential buildings and public buildings;
• two-story objects of the V degree of fire resistance (dry pipe is installed on the stairwells and displayed in the attic);
• monitor towers;
• cable structures, standing separately from buildings;
• elevators.

When installing a dry pipe, the following rules must be observed:

• In buildings of class F5.1 - F5.3, a pipeline with a diameter of 80 mm is mounted at the points where fire escapes are located.
• If the height of the building to the eaves is more than 10 meters and the width is 24 m, then the risers of the dry pipe are installed at the upper and lower ends of the riser.
• It is allowed not to place a dry pipe in buildings less than 24 m wide and not more than 10 m high to the eaves.

Dry pipes can be found in almost every room in the sauna. In small rooms, when the temperature rises, combustible gases accumulate, as a result of which a fire can start even without the presence of oxygen. In order to reduce the temperature in time and prevent an explosion or fire, a dry pipeline is installed.

Advantages and disadvantages of dry pipe systems

Dry pipeline has gained wide popularity due to the following advantages:

• ease of installation and operation;
• the possibility of replacing faulty parts without disrupting the operation of the complex;
• the system can be used in unheated rooms and at temperatures below 0 0 С;
• low cost;
• quick response to a fire and lowering the temperature in the room.

The use of a dry pipe contributes not only to the suppression of fire, but also prevents the spread of combustion products.

The dry pipe system has two significant drawbacks: a large irrigation area, even in cases where this is not necessary, and a significant consumption of water or foam.

Types of dry pipe systems

The pipeline itself is the same everywhere, the sprayers are different. Depending on the type of irrigation heads, the following types of dry pipes are distinguished:

• sprinkler;
• deluge.

The main distinguishing feature of sprinkler sprayers is the presence of a thermal lock, which prevents the bleeding of gas filling the working pipeline of the dry pipe complex. The sprinkler works only in the place where there are signs of a fire.

The central element of a dry pipe sprinkler is a water alarm valve, necessary to contain high pressure water. After reaching a certain temperature, the fusible lock disintegrates and the descent of air or inert gas begins. When the pressure rises to a critical level, the dry pipe valve provides water supply.

Drencher sprayers, unlike sprinklers, create a water curtain that prevents the spread of fire. They can have a different shape and are able to extinguish a fire not only with water, but also with foam or a finely sprayed composition.