Dry powder fire extinguishers use carbon dioxide gas or nitrogen gas as the power to spray dry powder fire extinguishing agents to extinguish the fire. Dry powder fire extinguishing agent is a dry, easy-to-flow fine solid powder composed of additives such as base material that can extinguish the fire and moisture-proof agent, flow promoter,
agglomeration preventer, etc. The main ones are ammonium phosphate, sodium bicarbonate, and chloride. Sodium, potassium chloride dry powder fire extinguishing agent, etc. It can be used to extinguish the initial fires of flammable liquids such as petroleum and organic solvents, combustible gases, and electrical equipment.
Dry powder fire extinguishers can be divided into three types: portable type, backpack type, and cart type.
Basic information Chinese name Dry powder fire extinguisher Physical form Dry, easy to flow fine solid powder Main components Ammonium phosphate, sodium bicarbonate, sodium chloride, potassium chloride Dry powder fire extinguishing agent scope of application can extinguish general fires, but also extinguish oil and gas Classification of fire caused by burning, portable, backpack, cart
Dry powder fire extinguishers can be divided into three types: portable type, backpack type, and cart type.
When using an external portable fire extinguisher, hold the nozzle with one hand and lift the lifting ring with the other hand, and the dry powder can be sprayed out. When using a trolley-type fire extinguisher, turn the back of the fire extinguisher toward the fire source (it should be placed in the upwind direction when outdoors), first remove the spray gun, unfold the powder outlet pipe (remember not to twist), and then lift the intake pressure rod to allow carbon dioxide to enter Storage tank, when the gauge pressure rises to 0. When 7 MPa ~ 1 MPa, lower the intake pressure lever to stop the intake. At this time, turn on the switch and spray dry powder to extinguish the fire from near to far. For example, when fighting an oil fire, do not make the airflow of dry powder directly impact the oil stain, so as to avoid splashing the oil surface and spreading the fire. When using a backpack-type fire extinguisher, stand at a distance of 5 to 6 meters from the edge of the flame, and hold the grip of the dry powder gun with your right hand (if it is powered by nitrogen, you can only hold the wooden handle, otherwise you may be frostbitten by the low-temperature gas), and your left hand Move the switch to position "3" (spraying sequence is 3, 2, 1), turn on the safety device, aim the spray gun at the fire source, pull the trigger, and the dry powder can be sprayed. If you can't put out the fire after spraying a bottle of dry powder, you can turn the switch to No. 2 or No. 1, and spray continuously until the spray is finished.
Note: When the lithium-ion battery warehouse is on fire, the dry powder fire extinguisher cannot effectively extinguish it. When the fire is large, it will be more difficult to put out the fire.
Dry powder fire extinguishers can be filled in various types of portable and fixed dry powder fire extinguishing devices. They can be combined with fluoro protein foam fire extinguishing agents and aqueous film foam fire extinguishing agents to put out the initial fire of oil tanks and quickly control the flame. Development, play a role in rapid-fire extinguishing. Dry powder fire extinguishers are widely used in oil fields, oil depots, refineries, chemical plants, chemical warehouses, ships, airports, and industrial and mining enterprises. The most commonly used method of opening a dry powder fire extinguisher is the pressing method. After lifting the fire extinguisher to a proper position from the fire source, first, turn it upside down several times to loosen the dry powder in the cylinder, and then aim the nozzle at the most violent burning place, remove the safety pin, press down the lever, and the fire extinguishing agent will spray out Extinguishing. When turning on the dry powder fire extinguishing rod, hold the middle of the fire stick with your left hand, aim the nozzle at the root of the flame, pull out the insurance card with your right hand, turn the opening knob, and open the gas cylinder. After a delay of 1-4 seconds, the dry powder will spray out to extinguish the fire.
Portable dry powder fire extinguisher adapts to fire and how to use it: 1 Sodium bicarbonate dry powder fire extinguishers are suitable for the initial fires of flammable, combustible liquids, gases, and live equipment; ammonium phosphate dry powder fire extinguishers can be used in addition to the above-mentioned types of fires, and can also extinguish the initial fires of solid substances. But none of them can put out a metal burning fire. When extinguishing a fire, you can quickly rush to the fire site with your hand or shoulder fire extinguisher. Put down the fire extinguisher about 5 meters away from the burning place. If you are outdoors, you should choose to spray in the upwind direction. If the dry powder fire extinguisher used is an external pressure storage type, the operator should hold the spray gun firmly in one hand and lift the opening lifting ring on the gas cylinder with the other hand. If the opening of the gas cylinder is hand-wheeled, unscrew it counterclockwise and rotate it to the highest position, then lift the fire extinguisher.
When the dry powder is sprayed out, quickly aim at the root of the flame and shoot.
If the dry powder fire extinguisher used is a built-in gas storage cylinder or a pressure storage type, the operator should first remove the safety pin on the opening handle, then hold the nozzle at the front end of the spray hose, and open the pressure handle with the other hand Press down and turn on the fire extinguisher to extinguish the fire. When using a fire extinguisher with a spray hose or a stored pressure fire extinguisher, always press down the handle with one hand and cannot let go, otherwise, the spray will be interrupted.
When fighting a flammable and flammable liquid fire, the dry powder fire extinguisher should be aimed at the main part of the flame. If the liquid fire to be extinguished is flowing and burning, it should be aimed at the root of the flame from near and far, and strafing left and right until the flame is completely extinguished. If combustible liquid burns in the container, the user should aim at the root of the flame and sway from side to side so that the jet of dry powder covers the entire surface of the container opening; when the flame is driven out of the container, the user should continue to spray until the flame is completely extinguished. When extinguishing a flammable liquid fire in a container, care should be taken not to directly aim the nozzle at the liquid surface to prevent the impact of the jet from splashing the flammable liquid and expanding the fire, causing difficulty in extinguishing the fire.
If the flammable liquid has been burned in a metal container for too long and the wall temperature of the container is higher than the spontaneous ignition point of the flammable liquid, it is very easy to cause the phenomenon of re-ignition after the fire is extinguished. If it is used in combination with a foam fire extinguisher, the fire will be extinguished. The effect is better.
When using ammonium phosphate dry powder fire extinguishers to put out solid combustible fires, they should aim at the most violent burning place and shoot up and down, left and right. If conditions permit, the user can carry the fire extinguisher and spray it along the circumference of the burning material, so that the dry powder extinguishing agent is sprayed evenly on the surface of the burning material until the flame is completely extinguished.
2 How to use trolley dry powder fire extinguisher: trolley type dry powder fire extinguisher is mainly used to put out flammable liquid, combustible gas, and electrical equipment in the first fire. The cart-type dry powder fire extinguisher is easy to move, easy to operate, and has a good fire extinguishing effect. Pull or push the fire extinguisher to the scene, hold the powder spray gun with your right hand, unfold the powder spray hose with your left hand until it is straight and cannot be bent or circled, then remove the lead seal, pull out the safety pin, and press it firmly with the palm of your hand Hold the air supply valve, and then hold the powder spray gun barrel holder with your left hand, and use your finger to hold the gun handle to turn the powder spray switch to aim at the flame spray. Keep swinging the powder spray gun forward and left to cover the combustion zone until the fire Fight is extinguished.
