Xinqiao Road, South of Far East Avenue, Lingang Economic Park, Gaogang District, Taizhou City, Jiangsu Province
Jiangsu AQZ Special Vehicle Equipment Co., Ltd.
Several ways to save fire from live equipment with water
With the increasing living standards of our people, the electricity consumption in urban and rural areas has increased sharply in recent years. The fires caused by electrical equipment or lines are frequent, especially in the northeastern region. Due to the low temperature, the use of electrical products for heating is caused. The line is overloaded or the use of electrical appliances is numb to forget to turn off the switch in time to catch fire.
The water can conduct electricity, and the water column of the DC water gun is used to save the fire of the electrical equipment that is charged, which is harmful to the body of the fire extinguisher. Therefore, in the case of equipment charging in the fire fighting, we generally have to cut off the power supply before proceeding to save. However, when it is impossible to cut off the power supply due to production or other reasons, it is necessary to electrify the fire.
When water is used to extinguish the fire, the charged body and the jetted water column, the water gun, the human body and the ground will form a current loop. The current passing through this loop has a direct impact on the safety of the human body. If we directly introduce the current obtained from the water column and the water gun into the earth and the body is insulated and protected, the safety of the firefighting personnel can be guaranteed. The following describes several methods of using water to extinguish fire.
First, install the grounding wire on the metal water gun nozzle
The grounding wire can be a copper stranded wire with a section of 5-10mm2 and a length of 1m or more. The grounding rod can be used with more than 1m, 50mm diameter steel pipe or 50×50mm angle steel, and the rescue personnel wear insulated gloves and insulating rubber boots. Before the fire extinguishing, the water gunner should firmly connect one end of the grounding wire to the metal water gun nozzle, the other end to the grounding rod, and the grounding rod into the ground. About 5 meters, and pour salt water or ordinary water at the ground rod. If the grounding wire is connected to other grounding devices, it is required to have good contact. When holding the water gun, the position of the hand must be placed behind the grounding wire, select the distance from the charged body, and then shoot the water.
Second, wear insulated gloves, insulated boots
Wear insulated gloves and insulated boots to extinguish the live fire. Use the most experienced water gunners to maximize the distance between the water gun nozzle and the charged body. Take effective measures to prevent water droplets from flowing into the gloves and rubber boots. On the front, facing the fire source, the method of spotting makes the water drop on the fire source. Under normal circumstances, it is best not to use a full water column directly to the fire source to prevent the risk of electric shock
Third, wear uniform pressure clothing
There are two kinds of pressure equalizing clothes currently used: one is made of cotton fiber or animal fiber and copper wire, which is made of warp and weft interwoven cloth, and the other is made of copper or silver plated with cotton cloth. These two pressure equalizations are applied to cotton or cotton bristles and contain large metallic conductors. The pressure equalizing garment made of this material includes: a hat, a glove, a garment, a sock, a shoe upper, etc., and the sole is made of a conductive rubber. When wearing the pressure equalizing suit, be sure to fasten the snaps between the clothes, gloves, socks and rubber shoes, twist the copper wires between them to form a good grounding wire, and then select according to the voltage. Shooting water distance, using a metal water gun to shoot water to save.
Fourth, the use of spray water
Use a spray gun or install a two-stage centrifugal spray head on the muzzle of the DC water gun to become a two-stage centrifugal spray gun. The water jet from this water gun has a good degree of atomization and is almost non-conductive. Experiments have shown that when the nozzle of the water gun is 5 meters away from the 127 kV charged body and is subjected to electrified fire extinguishing under 7 kg of water pressure per square centimeter, there is no leakage flow, and the range can reach 8-9 meters.
When using this spray gun to carry out electric fire extinguishing, the water gun can be directly grounded and extinguished without grounding. However, according to the voltage size, the safe distance from the charged body should be selected. The pump pressure of the fire truck should be kept at 0.5-0.7Mpa, and the sprayed water sprayed out of the water gun can be fired to the charged body to save the fire.
V. Specific measures for electrified fire extinguishing
1. Determine the voltage of the charged equipment and line
The fire commander should contact the person in charge of the unit or the electrician to find out the voltage of the fire equipment and the line, determine the minimum safe distance to be maintained, and then organize the fire. For power supplies with voltages below 250V, wear insulated gloves and cut the wires with insulated shears.
After consulting the data, the minimum safe distance that the human body and the charged equipment and lines must maintain are: 110 kV is greater than 1 m; 220 kV is greater than 1.8 m; and 330 kV is greater than 2.4 m.
2. Use a gas or dry powder fire extinguisher to extinguish the fire
For small-scale, small-scale live equipment or line fires, use carbon dioxide, 1211, FM200 or dry powder fire extinguishers to directly fire the fire. In view of the complex fire situation, in order to ensure safety, the human body and fire extinguishers must be kept away from live equipment and wiring to prevent striking voltage or reaching the discharge gap and causing electric shock and casualties.
3, enable fixed fire extinguishing device to extinguish
There are three main types of fixed fire extinguishing devices installed in electric power facilities: steam fire extinguishing devices; gas fire extinguishing devices; water spray fire extinguishing devices. After the fire brigade arrives at the scene, the fire commander should ask and check if the fixed fire extinguishing device is activated. If it is not activated, it should be activated as appropriate.
4. Use a spray gun to extinguish the fire
The pump pressure of the fire truck is adjusted to 0.7 MPa or more. After the water sprayed from the spray gun is in an atomized state, it is fired against the charged target.
5, using DC water gun to electrify fire
In the absence of live fire extinguishing equipment and spray water guns, the water column can be filled with a DC water gun, and tap water can also be used to extinguish high-voltage live equipment or line fires within 220 kV.
The specific method is: using a large-caliber water gun, standing 7 meters away from the charged object, the water gunner wears insulated boots, wears insulated gloves, uses spotting to carry out long-range water-fire extinguishing or makes the water flow parabolically fall on the fire point.
6, using a foam tube gun to extinguish the fire
The use of tap water and ordinary protein foam liquid sprayed through the foam tube gun to extinguish the high-voltage electrified fire is also very good, the resistivity is much larger than the tap water, the most suitable for saving large power transformers, cable trench fires.
Sixth, fire safety precautions
1. It is necessary to pay attention to the use of foamed fire extinguishing. When the foam is not formed, the charged body cannot be impacted. The area where the foam is flowing cannot be used to prevent leakage current from hurting people.
2, water gunners are best to wear insulated gloves, wear insulated boots, pressure-pressure clothing and other safety protective equipment, other personnel should not be close to the firefighters, burning areas and stagnant water areas that are being extinguished.
3, water gun nozzles, fire extinguishers and the human body must maintain a corresponding safe distance from high-voltage live equipment or lines.
4. When fighting overhead high-voltage live equipment or line fire, the water gunner should keep the horizontal distance as far as possible from the charged body to prevent the wire from falling off and endangering safety. When the high-voltage power line is broken, set a warning zone 20 meters away from the drop point of the wire to prohibit people from entering. Persons who are already in the area should be calmly disposed. In order to prevent the impact of striding voltage, first throw away the equipment in the hand, and use one foot or both feet to jump slowly and jump away from the charged body 10 meters away. .
5. The firefighter's body and equipment used in the vicinity of high-voltage live equipment or lines shall also maintain the necessary safety distance between the body and the used body. It is necessary to prevent the rescue tool from coming into contact with the charged body.
6. When the power is cut off at the power distribution room (box), the face should be facing away from the knife to prevent arc injury. After the power is cut off, special personnel should be designated to prevent the uninformed from closing the power at will.
7. When using a DC water gun to extinguish the fire, if a discharge sound or a discharge spark is found, and there is a sense of electric shock, take a horizontal position to shoot the water, and touch the metal of the joint between the water belt and the water gun to prevent electric shock and injury.
8. When fighting high-temperature electric heating equipment such as industrial electric furnace, electric oven, electric drying room, etc., gas or dry powder fire extinguisher should be used. It is strictly forbidden to use water to save. Because sudden cooling will damage the electric heating equipment under high temperature conditions, and the rapid evaporation and vaporization of water after contact with high-temperature electric heating equipment will cause explosion and furnace material splash, resulting in casualties or new fire points.