fire protection facilities are an important guarantee for the unit to improve its own fire resistance capabilities. Maintaining its good condition is related to whether the fire can be predicted in a timely manner, whether it can control and eliminate fires in a timely and effective manner, and whether it can provide assistance to personnel evacuation and fire-fighting and rescue operations. Through this section, you must be familiar with the basic concepts and working principles of common fire protection facilities, and focus on mastering the usage methods and operating requirements of common fire protection facilities.
1 fire doors and fire roller shutters
fire doors and fire roller shutters are generally installed on firewalls and have good fire resistance. Once a fire occurs in a building, it can effectively control the fire within a certain range. At the same time, it provides favorable conditions for safe evacuation of personnel and fire fighting.
(I) Fire door
Fire door refers to a door that can meet the requirements of fire resistance stability, integrity and thermal insulation within a certain period of time. It is usually set on fire-proof partition walls, evacuating stairwells, vertical shafts, etc.
1. Fire door consists of
Fire door is composed of door frame, panel (filled with heat insulation material), fireproof hardware accessories, electromagnetic door suction and other components. The door leaf is formed by hinge connection, and the door is equipped with door closeter and fire lock. The double door is also equipped with a hidden latch (installed on the side of the fixed fan) and a ranking device to prevent the middle joint of the door leaf from being stacked. The fire detector and the fire linkage control system are linked to the normally open fire door.
2. Fire door classification
3 is divided into materials: wooden fire doors, steel fire doors, steel wood fire doors, and other materials fire doors; according to the number of door leaves: single fire doors, double fire doors, and multiple fire doors; according to the structure type: fire doors with fire glass on the door leaf, single and double notch and double notch, fire doors with bright windows, and inorganic glass fire doors; according to the opening and closing state: normally open fire doors, normally closed fire doors; according to the fire resistance performance: heat-insulated fire doors (Class A), partial heat-insulated fire doors (Class B), and non-insulated fire doors (Class C).
3. Fire door control
Normally open fire door and normally closed fire door are both opened in the direction of evacuation. A single-fan fire door is equipped with a releaser and a single linkage module, and two fire door releasers and two single linkage modules are installed with double-fan doors. After the fire detector on either side of the fire door alarms, it reports it to fire alarm controller through the bus. The fire alarm controller issues an action command to the fire door linkage module. The linkage module drives the releaser to generate a release action. The released fire door is automatically closed under the elastic force of the door closer. At the same time, the fire door releaser inputs the fire door status signal into the single linkage module and then sends it to the fire control room through the alarm bus.
(II) Fireproof Roller Blind
Fireproof Roller Blind refers to a roller blind that can meet the fire resistance integrity requirements within a certain period of time. Fire-proof roller shutters are fire-proof partitions. The fire-proof roller shutter with vertical roll is usually rolled up and placed in the shaft box above the door and window openings. When the fire catches, it is placed down and spreads to prevent the fire from spreading from the door and window openings. Fireproof roller shutters are generally set around escalator , the atrium and the walkways on each floor, the hall, the room, and the openings where fireproof partition facilities are required instead of the firewall.
1. Fireproof roller blinds are composed of curtain plate, seat plate, guide rail, support, reel, box, control box, door rolling machine, limiter, door lintel, manual speed release switch device, button switch and safety device. Equipment linked to fireproof roller shutters include smoke sensing, temperature sensing detectors and fire linkage control systems.
2. Fireproof roller blind classification
Fireproof roller blinds can be divided into ordinary steel fireproof roller blinds (fire resistance limit ≧2h), composite steel fireproof roller blinds (fire resistance limit ≧3h), and special fireproof roller blinds (fire resistance limit ≧4h). When ordinary steel fireproof roller blinds are used for fire separation, the fireproof roller blinds must be protected by automatic sprinkler system .
3. Fireproof roller blind control
automatic control: After the fire detector is operated, in the case of linkage, the fireproof roller blind used as the fireproof partition will drop to the bottom; when used as the fireproof roller blind on the evacuation channel, the roller blind will drop to 1.8m from the ground first, and after another temperature sensing detector is operated, the roller blind will drop to the bottom.
Mechanical operation: first take out the chain, pull the chain on the roller shutter side down, and the roller shutter will descend; pull the chain on the other side down, and the roller shutter will rise up.
manual operation: open the manual operation box located on both sides of the roller shutter or on the nearby building components, press the "up" (or marked "Δ" graphics) button, the roller shutter rolls upward, press the "down" (or marked "" graphics) button, the roller shutter falls; press the middle button, the roller shutter stops running; the other is: press the manual construction corresponding to the control module that drives the roller shutter door downward in the fire control room, and when the roller shutter reaches the designated position, the feedback signal will be sent to the fire control room.
2 Fire automatic alarm system
Fire automatic alarm system is an automatic fire protection facility set up in buildings or other places, which can detect and report fires in advance.
(I) System consists of
fire automatic alarm system usually consists of triggering devices such as fire detectors, alarm devices such as fire alarm controllers, alarm devices such as acousto-light alarm , linkage control devices such as bus control panels and control modules, power supplies, etc.
(II) Working principle
Fire automatic alarm system In the early stage of the fire, the smoke, heat, optical radiation and other physical quantities generated by combustion will be turned into electrical signals through fire detectors such as smoke sensing, mild light sensing, etc., and transmitted to the fire alarm controller. After the signal is processed, analyzed and judged by the fire alarm controller, it is displayed in sound, light, text, etc. and the location of the fire occurs at the same time, recording the time of the fire occurrence.
(III) Linkage control
fire automatic alarm system is generally linked to pre-acting systems, rain shower system, water curtain system, water spray system, water cannon system, gas fire extinguishing system, , smoke prevention and exhaust system, ventilation system, air conditioning system, normally open fire door, fire roller shutter, smoke blocking wall , fire broadcast and other equipment. In the case of fire, if the controller is in the automatic state, it will automatically start the smoke-proof fan, stop the new fan, close the fire valve , release the fire door, fire-proof roller shutter, and smoke-blocking wall, etc., and can automatically start the pre-acting, rain shower, water curtain, water spray and water cannon pump, and cannon pump can be directly started in the fire control room.
3 smoke prevention and exhaust system
smoke prevention and exhaust system is a building facility set up to control the flow of smoke in a fired building, create conditions conducive to safe evacuation and fire rescue, and prevent and reduce the harm of building fires. The smoke prevention and exhaust system is divided into mechanical pressurized air supply and smoke prevention facilities and mechanical smoke exhaust facilities.
(I) System consists of
smoke exhaust system, main components: smoke exhaust fan, electrical control cabinet, air duct (air duct), fire valve, air outlet , smoke exhaust port, manual control device, fire detector, fire linkage control system, etc.
(II) Setting up the site
1, mechanical pressurized air and smoke prevention facilities
Mechanical pressurized air and smoke prevention facilities are mainly located in: smoke-proof stairwells without natural smoke exhaust conditions, fire elevators or combined front rooms ; smoke-proof stairwells that adopt natural smoke exhaust measures, their front rooms without natural smoke exhaust conditions and enclosed refuge floors (rooms).
2, mechanical smoke exhaust facilities
Mechanical smoke exhaust facilities are mainly located in: inner walkways with a building length greater than 20.0m and no natural smoke exhaust conditions, singing, dancing, entertainment venues with a room building area greater than 200m2, as well as public buildings with an area exceeding the specified area, C factory buildings , C warehouses, etc.
(III) Working principle
smoke prevention and exhaust facilities are generally linked to the fire alarm system. When the control operation table (cabinet) of the control center is in an automatic state, after a fire alarm occurs, the smoke prevention and exhaust system will be linked. The mechanical pressurized air supply opportunity will automatically start, and the smoke prevention and ventilation will be pressurized to the smoke-proof stairwell, fire elevator housing front room or combined front room that does not have natural smoke exhaust conditions to prevent the inflow of smoke gas; at the same time, the fire valve of the corresponding smoke prevention zone will automatically open. After the mechanical smoke exhaust fan starts automatically, thick smoke will be discharged outward to the smoke exhaust pipe or vertical shaft through the smoke exhaust port. When the temperature reaches 280℃, the smoke exhaust fan will automatically stop.
When it cannot be started automatically, it can also be started remotely in the fire control center, or directly start the positive pressure blower and smoke exhaust fan in the fan room.
4 outdoor fire hydrant water supply system
outdoor fire hydrant is mainly used to provide fire water to fire trucks, or directly connect to fire water belt and water guns on outdoor fire hydrants to extinguish fire. It is an essential fire water supply facility for urban infrastructure construction.
(I) The system consists of
outdoor fire hydrant mainly consists of: body, bent pipe, valve seat , valve disc, drain valve, valve stem and fire interface. It is divided into two types: above ground and underground type. The upper part of the above ground type is exposed to the ground, the logo is obvious, it is easy to use, and the underground type is installed underground without affecting the city appearance.
(II) Layout requirements
Outdoor fire hydrants should be paved along the road. When the road width exceeds 60m, it should be set on both sides and close to the intersection. The layout interval should not be greater than 120m, the distance from the edge of the road should not exceed 2m, the distance from the exterior wall of the building should not be less than 5m, or more than 150m, and the distance from the exterior wall of the high-rise building should not be greater than 40m. The number of outdoor fire hydrants should be determined based on their protection radius, flow rate and outdoor fire water consumption. The flow rate of each outdoor fire hydrant should be calculated as 10--15L/liter.
The ground fire hydrant is installed and easy to detect, making it convenient for water outlet operation. The underground fire hydrant should have obvious fixed signs near the ground.
(III) Method of use
Fire hydrant is closed normally, the valve disc seals the water inlet. When using it, first connect the fire truck suction pipe with an interface with a diameter of 100mm (150mm), or connect the water belt with an interface with a diameter of 65mm. However, if you open the valve with a special wrench, the municipal water supply of the underground pipeline network will flow into the fire hydrant. The fire truck can directly absorb water and supply water, and the water belt can also directly exit water to extinguish the fire. After use, close the valve and the residual water in the valve body can be automatically discharged by the drain valve.
5 Indoor fire hydrant water supply system
Indoor fire hydrant system is one of the main fire protection facilities in a building, Indoor fire hydrant is the main tool for unit employees or firefighters to extinguish fires.
(I) System consists of
indoor fire hydrant system mainly consists of fire hydrant box , indoor pipeline network, fire water tank , municipal entrance pipe, fire water pool, fire pump group, water pump connector , fire pump control cabinet, test fire hydrant, etc.
(II) Spacing requirements
High-rise civil buildings , high-rise industrial buildings, elevated warehouses and Class A and B production plants should not exceed 30m; in other single-story and multi-story buildings, as well as in podiums directly connected to high-rise buildings, it should not exceed 50m.
(III) Methods for use
Indoor fire hydrants are generally set on the walls of public parts of the building, with obvious signs, including water strips and water guns, and some also fire reels . When using a fire reel, open the door of the fire hydrant box, pull out the hose, and turn on the small-diameter water gun switch to spit out the fire; when using water belt , open the door of the fire hydrant box, take out the water belt and water gun, connect one end of the water belt to the fire hydrant water outlet, connect the water gun at the other end, straighten the water belt, press the fire hydrant start pump button, start the fire hydrant pump , and then open the fire hydrant valve to spray water to extinguish the fire.When the fire hydrant pump control cabinet is in a manual state, someone should be sent to the fire pump room to manually start the fire hydrant pump.
6 Automatic sprinkler fire extinguishing system
Automatic sprinkler fire extinguishing system is a fixed automatic fire extinguishing facility. It automatically detects fires and automatically controls the application of fire extinguishing agents. It is divided into closed system and open system according to the opening and closing form of the sprinkler on the pipeline network. The closed automatic sprinkler system also includes: wet system, dry system, pre-acting system, and circulation system; the open automatic sprinkler system also includes: rain fire extinguishing system , water curtain system, and water spray system.
(I) Wet automatic sprinkler fire extinguishing system
Wet automatic sprinkler fire extinguishing system. Since the front and rear pipelines of the alarm valve are always filled with pressure water, it is called
wet sprinkler fire extinguishing system.
1, system composition: it consists of closed nozzle, pipeline system, wet alarm valve group, water flow indicator ,
waterproof source and water supply facilities.
2. Working principle: Under the action of the fire temperature, when the temperature rise of the temperature sensing element of the closed nozzle reaches the predetermined dynamic
as the temperature, the nozzle opens and sprays water to extinguish the fire. When the water flows in the pipeline network, the upper water pressure of the wet alarm valve drops. The valve disc originally in the closed state is affected by the pressure difference and opens itself. Water flows to the main pipe and branch pipe through the wet alarm valve. The water flow indicator on the main pipe changes from the water flow signal to the electric signal to transmit to the controller. After passing through the delay, the water in the branch pipe leads to the hydraulic alarm and the pressure switch. The water flow hits the hydraulic alarm and emits a sound alarm signal, and at the same time makes the pressure switch contact. First, the contact signal is feedback to the controller, and second, the contact signal will directly start the spray pump , so that the pipeline network can continuously pressurize and supply water, achieving the purpose of automatic water spray extinguishing.
After spraying water, the water flow indicator and pressure switch will alarm the alarm controller, and the information will also be fed back to the alarm controller after the spray pump is started. There are two ways to source the power source for the pressure switch of
: one is supplied by the fire control device, and the other is supplied by the pump room power control cabinet.
The pressure of the spray main pipe is generally not more than 12 kg. If the pressure is too large, the water supply should be divided into sections, and the branch pipe is generally not more than 4-5 kg. If the pressure is too large, the pressure should be reduced. After the valve leading to the delay valve of the wet alarm valve opens, the spray pump starts immediately, because the valve is not tightly closed.
The spray pump has no faults, but after opening the end and draining water, the spray pump still cannot start? The main reasons are: the pressure of the wet alarm valve under pressure gauge is too low (no pressure stabilization or the roof water tank pipe is not open), the pressure switch cannot be contacted, and the small hole under the delay becomes larger. Why can't the spray pump stop after the end of the discharge and close the valve? The main reason is that the pressure switch cannot automatically disengage.
end water discharged for 90 seconds but the pump was not turned on. The main reason is that the pressure of the lower pressure gauge of the wet alarm valve is too low (no pressure stabilization or the roof water tank pipe is not open), the pressure switch cannot be contacted, the small hole under the delay device becomes larger, the spray control cabinet is not placed in the automatic position, and the power supply of the pump is turned off.
(II) dry sprinkler fire extinguishing system
dry sprinkler fire extinguishing system is developed on the basis of wet systems to meet the needs of installing automatic sprinkler fire extinguishing systems in cold and high-temperature places. Since there is no water in the pipeline and nozzle usually only in the inflatable state, it is called a dry system or a dry pipe system.
1, system composition: it consists of closed nozzle, pipeline system, dry alarm valve groups, water flow indicator, inflation equipment, exhaust equipment, fire water source and water supply equipment, etc.
2. Working principle: When a fire occurs, under the action of the fire temperature, the temperature of the closed nozzle's temperature rises. When the nozzle reaches the predetermined operating temperature range, the nozzle is opened, and the compressed air in the pipeline is sprayed out from the nozzle, causing the pressure on the outlet side of the dry alarm valve to drop, the dry alarm valve is automatically opened, and water enters the pipeline and is sprayed out from the nozzle.While the dry alarm valve is opened, the channel leading to the hydraulic alarm is also opened. The water flow hits the hydraulic alarm and emits a sound alarm signal. The pressure switch alarm signal is sent to the alarm controller , and the fire pump is directly activated to pressurized water supply.
(III) pre-acting sprinkler fire extinguishing system
pre-acting sprinkler fire extinguishing system is a fire extinguishing system that organically combines wet systems, dry systems, and fire alarm systems. The system's valve rear pipeline network is dry, and the front pipeline network in front of the valve is wet. During a fire, the control of the pre-acting valve is achieved through the fire automatic alarm system, and the pipe network behind the valve is immediately filled with water, converting the system into a wet type, so it is called the pre-acting sprinkler fire extinguishing system.
1, system composition: it consists of fire detectors, alarm control devices, closed nozzles, pipeline systems, pre-acting valve groups (or rain valve groups), manual opening valves, inflatable equipment, exhaust devices, fire water sources and water supply facilities, etc.
2. Working principle: The system valve rear pipe network is generally filled with low-pressure compressed air. When a fire occurs, the fire detector installed in the protection area first emits a fire alarm signal. When the fire controller receives the alarm signal, on the one hand, it automatically opens the exhaust valve to exhaust, and on the other hand, it automatically opens the solenoid valve to drain. The valve disc originally in the closed state is affected by the pressure difference and opens itself, so that the pressure water quickly fills the pipe network. In this way, the original dry system quickly turns into a wet system, and the subsequent actions are the same as the wet system.
(IV) Rain sprinkler fire extinguishing system
When the rain sprinkler fire extinguishing system is working, all sprinklers spray water at the same time, like pouring rain, so it is called a rain sprinkler system or flood system.
1, system composition: it consists of fire detection and alarm control devices, open nozzles, pipeline systems, rain valve groups, manual opening valves, fire water sources and water supply facilities.
2. Working principle: When a fire occurs, the fire detector sends the signal to the fire alarm controller. The controller outputs the signal to open the rain valve to make the open nozzle in the entire protection area extinguish the fire. At the same time, start the water pump to ensure water supply, and call the pressure switch and hydraulic alarm together.
When there is no water spray after the automatic alarm linkage, the solenoid valve should be opened manually.
(V) water spray fire extinguishing system
water spray fire extinguishing system is often used to protect combustible liquids, gas storage tanks, oil-immersed power transformers, etc. The composition and working principle of the water spray fire extinguishing system are basically the same as that of the rain system. The main difference is that the structure and performance of the nozzles are different. The rain shower system uses a standard open nozzle, while the water spray system uses a medium-speed or high-speed spray nozzle.
pre-acting system, rain fire extinguishing system, water spray fire extinguishing system and automatic control water curtain system should immediately open the solenoid valve after the fire alarm system alarms, automatically supply water to the water distribution pipeline, and also have three methods of starting the water supply pump: automatic control, manual remote control of the fire control room and on-site emergency operation.
7 Foam Fire Extinguishing System
Foam Fire Extinguishing is one of the most effective fire extinguishing agents for extinguishing Class B fires. It has the characteristics of safety, reliability, economical and practical, and high fire extinguishing efficiency.
(I) System consists of
foam fire extinguishing system consists of fire water source, fire pump group, foam liquid supply source, foam proportion mixer , pipelines and foam generation device, etc.
(II) System classification
Foam fire extinguishing system is divided into three types according to the installation and use method: fixed, semi-fixed and mobile; according to the foam jet position, it is divided into two types: liquid upper jet and liquid lower jet; according to the foam foaming multiple, it can be divided into three types: low, medium, and high.
(III) Working principle
Fire pipe network water outlet process, the foam liquid and water are mixed in proportion through a proportional mixer to form a foam mixed liquid. The foam mixture liquid passes through the foam generator and mixes with the inhaled air, foams to produce foam, and sprays the foam to the surface of the combustion liquid to form a foam layer, isolate the air, absorb heat, and extinguish the fire. Foam fire extinguishing is mainly used to extinguish Class B fires, and can also extinguish Class A fires.
(IV) Method of use
1. Fixed foam fire extinguishing system
oil tank fire occurs, the on-duty personnel must first start the fire pump and fill the fire pipe network with water. At the same time, on the one hand, the foam and cooling pipe valves of the ignition tank, and on the other hand, the cooling pipe network valves of the adjacent tanks must be opened. However, check whether the foam liquid tank output pipeline valve is open, whether the output ratio is normal, and whether the foam liquid storage is sufficient.
After the fire brigade arrives, the commander first checks whether the fire pump is started and whether the output foam is normal. If it is found that the fire pump is not started or the output foam is abnormal, a person should be sent to start and inspect immediately.
2. The upper half-fixed foam fire extinguishing system
The liquid upper half-fixed foam fire extinguishing system is to fix the foam generator on the oil tank, and set the lower pipe part outside the oil tank protective berth (the pipe is connected outside the protective berth, 1 meter above the ground height, the end is installed with an interface, and the cover is usually buckled). Its foam mixture is provided by the mobile foam fire truck . When a fire broke out, the foam fire truck arrived at the fire site. The firefighters connected the water belt interface outside the protective berth, adjusted the proportion mixer, and raised the outlet pressure of the on-board fire pump to the normal working pressure, opened the outlet ball valve of the fire truck, and supplied the foam mixture to the semi-fixed system. When passing through the generator, air was sucked in to produce foam.
3. Mobile foam fire extinguishing system
Use of mobile foam systems generally means that the oil tank does not have a fixed fire extinguishing system, or the top of the oil tank is exploded in the event of a fire, or the fixed fire extinguishing system is damaged. The mobile fire extinguishing system mainly uses fire foam vehicles, which directly sprays foam into the oil tank to extinguish the fire, or uses fire trucks to adjust the working pressure (including the foam mixture ratio), and then sends mixed liquid to the mobile foam gun, foam gun, , foam hook tube, foam hook tube, , foam hook tube, , foam, , foam hook tube, , , tide fire.
You can use foam car-out foam gun or foam bolt-out pipe gun to spray foam to extinguish the fire.
8 gas fire extinguishing system
gas fire extinguishing system is used in specific places. Since the gas fire extinguishing system does not leave any traces after extinguishing the fire and does not affect the normal operation of the equipment, it is an ideal automatic fire extinguishing system.
(I) System consists of
gas fire extinguishing system consists of storage devices (starting gas cylinders, fire extinguishing gas cylinders), start-up distribution devices, pipelines, conveying and release devices, fire detectors, fire controllers, monitoring devices and other facilities.
(II) System Classification
Gas fire extinguishing system According to the fire extinguishing agent used, it is divided into: carbon dioxide fire extinguishing system, halogenated alkyl fire extinguishing system, smoke-fighting system and aerosol fire extinguishing system; according to the fire extinguishing method, it is divided into: a fully submerged gas fire extinguishing system, a locally applied gas fire extinguishing system; according to the layout of the pipeline network, it is divided into: a pipe network fire extinguishing system and a pipe network fire extinguishing system.
(III) Working principle
Working principle of gas fire extinguishing system: After the fire control center receives the fire signal, it starts the linkage device (close the opening, stop the air conditioner, turn on the alarm, etc.). After a delay of about 30 seconds, open the solenoid valve of the starter cylinder, use the high-pressure nitrogen in the starter cylinder to open the container valve of the fire extinguishing cylinder, and the fire extinguishing agent is transported to the nozzle through the pipeline to spray gas to extinguish the fire. The delay in the middle is to consider the evacuation of personnel in the protective area.
(IV) System control
In order to ensure that the system starts in a timely and reliably in the event of a fire, the system's control and operation should meet certain requirements. The pipeline gas fire extinguishing system generally has three starting methods: automatic control, manual control and mechanical emergency operation; the pipeline fire extinguishing system should have two starting methods: automatic control and manual control; when locally used gas fire extinguishing systems are used in protected places where people often have, automatic control may not be installed.
9 Fire Control Room
Fire Control Room is the information control center of building fire protection facilities and is also the fire extinguishing command center during fires. It plays a very important position and role.
(I) Control room location
Fire control room should be located on the first floor of the building, and signboards or sign lights should be installed above the door of the fire control room. The signs on the door of the fire control room on the ground floor must be equipped with a lampshade. The power supply of the sign light should be connected from the fire power supply to ensure the reliable power supply of the sign light. In order to prevent fire from endangering the safety of fire control room staff, the door of the fire control room should have a certain fire resistance (i.e., a Class A thermally insulated fire door), and should be opened in the direction of evacuation, and should have a safety exit.
(II) Control equipment function
Fire control equipment has the start and stop of fire water pumps, smokeproof and smoke exhaust fans. In addition to automatic control, it can also be manually controlled directly. When a fire occurs, in automatic situations, it will automatically close the normally open fire door, fire roller shutter door, , and electric fire valve, stop the air supply of air conditioners in relevant parts, force the elevator to lower the elevator, cut off the non-fire power supply of relevant parts, and connect the alarm device, fire emergency lights and evacuation sign lights, start the emergency broadcast, and receive its feedback signal. It can also have a control and display function for the gas fire extinguishing system and foam fire extinguishing system.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-