Working Principle and Operating Precautions of ISUZU Dry Powder Fire Truck
The correct use of Isuzu dry powder fire trucks means that when a fire occurs, it can quickly and effectively extinguish the fire and protect people's lives and property. Isuzu dry powder fire trucks have strong fire extinguishing capabilities and can drop dry powder at the fire scene to control and eliminate the fire. It is also highly maneuverable and adaptable to a variety of environments and fire types, including buildings, vehicles, forests and more. The correct use of Isuzu dry powder fire trucks requires professional knowledge and skills, including understanding different fire spread patterns, taking appropriate extinguishing methods in a timely manner, and complying with operating procedures and safety regulations. Its correct use can minimize the losses caused by fire and protect the stability and development of society.
1. Working principle of dry powder nitrogen system
a) When the dry powder fire extinguishing agent is launched, the system uses nitrogen as the power, and the gas potential energy is converted into kinetic energy to perform work, and the dry powder is ejected from the muzzle (or muzzle) to extinguish the fire.
b) When working, open the nitrogen bottle head valve, the high-pressure nitrogen is reduced to 1.4MPa through the pressure reducing valve, open the inlet ball valve, and inflate the front and rear dry powder tanks. When the pressure inside the tank reaches 1.4MPa, the pressure reducing valve is in a balanced state and stops air intake into the tank. Open the powder discharge ball valve of the cannon (gun) to spray powder. The pressure in the tank will decrease, and the pressure reducing valve will automatically open, and continue to inflate the tank until the end of the work.
c) Immediately after extinguishing the fire, close the powder discharge ball valve and inlet ball valve of the cannon (gun). The remaining gas in the nitrogen bottle will be used to purge the pipeline. Open the gun (gun) purge ball valve to purge.
d) The dry powder tank is a pressure vessel containing dry powder. Nitrogen enters from the bottom of the tank through the pipe and strongly stirs the dry powder, making the mixture in the tank in a boiling state. When the pressure in the tank reaches the rated working pressure, open the powder discharge ball valve of the gun (gun). , the air powder flow is sprayed through the dry powder cannon (gun), and the pressure in the tank can be read from the pressure gauge on the cannon and the pressure gauge in the front equipment compartment. A safety valve is installed on the top of the dry powder tank to ensure the working safety of the dry powder tank.
2.Usage and operation methods
A. Inspection before use
1) Check whether each purge ball valve, residual ball valve, and inlet ball valve are in the closed position.
2) Check whether the dry powder can rotate up, down, left and right flexibly.
3) Check whether the powder ball valve is in the closed position.
4) Check whether the dry powder ball valve and control valve work flexibly and reliably. The pressure gauge indication value of the low-pressure reducer must be greater than or equal to or greater than 0.6MPa before it can be used.
5) Check whether the dry powder cannon loading control ball valve is in the "0" position.
B. Powder loading operation
1) Before loading powder, check whether the flange bolts at the bottom of the dry powder tank where the remaining powder is placed are loose, and whether the rubber sealing ring is properly padded. If the above phenomenon occurs, reinstall it and tighten the bolts evenly.
2) Open the powder filling port cover. Check whether there is accumulated water, debris and moisture agglomerated remaining dry powder in the tank. If there is any, it should be removed. When loading powder, it is strictly forbidden to put agglomerated dry powder and debris into the tank to avoid clogging the pipeline and causing accidents. Try to avoid loading powder in high temperature and humid climates.
3) When installing the powder filling cap, the jar mouth, cap and sealing gasket must be wiped clean, and there should be no dry powder and other debris to avoid seal leakage.
C. Want to inflate the tank
1) Open all nitrogen cylinder valves.
2) Adjust the pressure reducing valve so that the outlet pressure of the pressure reducing valve reaches 1.4MPa. When adjusting the pressure regulating screw of the pressure reducing valve, move slowly so that the pressure gradually reaches the predetermined working pressure of 1.4MPa evenly.
3) Open the ball valve as shown on the signboard, and sit on the air inlet hose to inflate the tank. When the pressure in the tank reaches 1.4MPa, the pressure reducing valve is in a balanced state and automatically stops the air supply. The pressure value in the dry powder tank is displayed by a pressure gauge installed on the gun or in the equipment box. At this point, the filling of the tank is completed.
D. Operation of dry powder launch gun
1) Check whether each reversing valve on the gun control panel is in the "0" position.
2) Loosen the horizontal locking handle so that the dry powder cannon can rotate within 360 degrees in the horizontal direction; loosen the vertical locking handle and the clamping force for positioning the dry powder cannon in the vertical direction disappears, and the dry powder cannon can rotate in the vertical direction (-15 degrees —+30 degrees).
3) The angle between the control armrest of the dry powder cannon and the barrel can be adjusted. Turn the lock nut counterclockwise to disengage the clutch claw from the base of the gun body. Turn the cannon control armrest to a suitable angle, tighten the lock nut, and the clutch claw engages with the gun base. .
4) When using a dry powder cannon to spray powder, do not spray against the wind.
5) When the two front and rear dry powder tanks are in use, observe the front tank pressure gauge and rear tank pressure gauge on the dry powder cannon control panel. When the pressure gauge reaches 1.4MPa, turn the front tank powder outlet valve and rear tank powder outlet valve on the instrument panel to the "open" position. The powder discharge ball valves of the front and rear tanks are opened, and the dry powder cannon can spray powder. After extinguishing the fire, turn the quantity control valve to the "off" position and close the powder outlet ball valve. Finally, turn the control valve to the "0" position.
6) The front and rear dry powder tanks can be used separately. At this time, only 6 of the 12 nitrogen bottles need to be opened. This way, the high-pressure gas of a group of nitrogen bottles can be retained for future use. After opening 6 nitrogen bottles, inflate only one dry powder tank. When the pressure of the tank reaches 1.4MPa, open the powder outlet ball valve of the tank to put out the fire. At this time, the front tank should be used first.
7) After using the dry powder cannon, open the purge ball valve of the cannon, purge the powder outlet pipe of the cannon, and tighten the positioning handle to reset the cannon.
E. How to use dry powder gun
1) The dry powder gun is placed in the equipment compartment at the rear of the vehicle and is led out from the rear tank. When using it, you only need to inflate the rear tank.
2) Take out the dry powder gun and pull out the hose. Pay attention that the hose must not be twisted or twisted.
3) At this time, you only need to open 6 of the 12 nitrogen bottles. After opening the 6 nitrogen bottles, only inflate the rear tank. When the pressure in the tank reaches 1.4MPa, open the gun powder discharge ball valve, and then pull the gun trigger to dry the powder. That is, sprayed from the muzzle.
4) After extinguishing the fire, close the air inlet valve of the rear tank and the powder discharge valve of the gun.
5) Open the gun purge ball valve to purge the remaining dry powder in the hose, and then wrap the hose onto the reel. Put the dry powder gun back into place and lock the reel.
F. After purging, close the nitrogen bottle valve, open the inflation angle valve on the high-pressure gas collecting pipe, release the remaining air in the high-pressure pipeline, and then close it.
G. Open the relief valve of the pressure reducing valve, release the remaining air in the pressure reducer, and close the relief valve. Loosen the pressure-regulating screw so that the adjusting spring is in a free state, and then use the back nut to fix the pressure-regulating screw.
H. After inflating, if there is no powder spraying or only a part of the dry powder is sprayed out, the residual air stored in the tank should be released. At this time, open the front and rear tank residual air valves. The two ball valves are located in the equipment box on the right side of the front body of the vehicle.
3. Maintenance
a) Every time you come back from the vehicle, check whether all riding bolts, nitrogen bottle locks and other fasteners are loose. Any loose parts must be retightened. Inspect them once a quarter thereafter.
b) The garage should be kept clean and dry.
c) When the vehicle is parked with a full load, the tires, spring steel plates, etc. will be at full load for a long time, which will affect the service life of the entire vehicle. Therefore, when the vehicle is parked, an auxiliary support frame should be placed under the rear crossbeam to reduce the burden on the rear axle.
d) Ensure that the vehicle has sufficient fuel, lubricating oil, and cooling water, and add and replace them regularly.
e) Frequently check whether the circuit, gas circuit and oil circuit are normal.
f) In addition to the maintenance, upkeep and inspection of nitrogen cylinders in accordance with relevant national regulations on gas cylinders, this vehicle requires the cylinder pressure to be checked once every three months. If the pressure is lower than 12.5MPa, it should be re-inflated.
g) Dry powder tanks are pressure vessels and should be maintained and inspected in accordance with regulations. Dry powder tanks undergo a pressure test every three years. The pressure test uses a hydraulic test. The test is conducted in accordance with relevant regulations. Dry powder tanks should be inspected regularly. There should be at least one external inspection every year, an internal inspection every three years, and a comprehensive inspection every six years. During the internal inspection, it is also necessary to check the three air inlet one-way valves at the bottom of the tank. After the powder is discharged, the one-way valves can be opened to check whether the pipeline is blocked by dry powder and corroded by steel balls. If there is any blockage, it should be removed. Clear the air intake pipe. If the steel ball is severely corroded, please replace it. The diameter of the steel ball is 20mm. The opening pressure of the safety valve on the dry powder tank is 1.5-1.65MPa, and the safety valve should be inspected at least once a year.
h) The dry powder cannon should be checked frequently to ensure flexible rotation. The lubricating grease in the oil cup should be filled up. The powder outlet ball valve and dry powder cannon should be wiped and cleaned after each use.
i) Various pressure gauges on the vehicle should be inspected regularly, at least once a year; pneumatic ball valves should be inspected frequently to maintain flexible movement and reliable operation; all valves should be opened and closed frequently to maintain flexible opening and reliable closing; the vehicle should be scrubbed clean after use.