Fires that cannot be extinguished with water should be extinguished with carbon dioxide, dry powder extinguishers or dry sand. Take the example of electrical fires. When a fire breaks out, you must first turn off the power supply. If the power supply cannot be turned off, do not use water or foam to extinguish the fire, as water and foam can conduct electricity. . Use carbon dioxide, dry powder extinguishers or dry sand to extinguish the fire and keep a distance of more than 2 meters from equipment and electrical wires.
Also, when the oil pan is on fire, never pour water on it. Because the water will form a "fryer" when it meets hot oil, causing it to splash everywhere. The method of extinguishing the fire is to quickly pour the cold cut vegetables into the pot along the edge, and the fire will go out automatically.atically. Another method is to cover the burning oil pan with a pan lid or a large piece of damp cloth that can cover the oil pan, so that the burning oil fire cannot reach the air, lack of oxygen and suffocation.
Fires that cannot be extinguished with water.
1. Fire with chemical risk. When hazardous chemical materials catch fire, a certain amount of sulfuric acid, nitric acid, hydrochloric acid, alkali potassium, sodium, lithium and flammable metal aluminum powder, magnesium powder, etc. . are often stored in school laboratories. These items react very easily or burn when exposed to water and should not be extinguished with water. Potassium carbide, sodium carbide, aluminum carbide, calcium carbide, potassium hydride, magnesium hydride, etc. can react chemically whenThey are exposed to water and release a large amount of heat, which can cause fires and explosions.
2. Alkaline metal fire. Alkali metal fire (such as potassium, sodium, zinc powder): When water encounters alkali metal, a violent chemical reaction occurs to generate a large amount of hydrogen, releasing a large amount of heat, which can easily cause an explosion. For this type of fire, it is necessary to choose the right extinguishing agent and to use local resources rationally.
3. Metal carbide and hydrogen fires. For example, carbide (carbide) decomposes when exposed to water and releases a large amount of heat, which can easily cause combustion to expand or explode.
4. Sulfuric acid, nitric acid and hydrochloric acid fires. This type of fire should not be extinguished with a high flow of eau, because when the acid contacts water, it will cause splashing and flowing, which may cause injury to people. When acid flows and comes into contact with flammable substances, there is. a risk of burns. However, if necessary, water spray can be used to extinguish the fire. Fires involving flammable liquids lighter than water or insoluble in water: In principle, such fires cannot be extinguished with water, but crude oil and heavy oil can be extinguished with water spray.
Reference for the content above? Emergency Management Service - What fires cannot be put out with water?
What is the abnormal noise of the Bora model 10 generator?
It is the noise caused by the friction between the belt and the pulley. The sound is temporary if you pour water on it, the motor will sound again after running for a cesome time. If the belt is a little loose, there will be a loud noise when the motor accelerates or the electrical load is high. Unless the belt is too loose or is aged and hardened, the friction noise will continue as described. , the belt is aged and hardened. The reason is that it needs to be replaced.
Check if it is the noise coming from the cylinder block. Otherwise, it can be determined that it is related to the car's starting system. When inspecting, if the belt is broken or has burrs; pay attention if the position of the starter is deviated, or if the belt connecting the starter is aged or bent; check engine idle speed;Dad. Carry out timely inspections and repairs, and even minor car problems should not be ignored.
Detailed information:
The timing belt is a consumable part, and once the timing belt is broken, the camshaft will definitely not work according to timing. At this point, it's very likely. to cause the impact of the valve on the piston causes serious damage, so the timing belt must be replaced according to the mileage or time specified by the original manufacturer.
The timing belt is a rubber component. As the running time of the engine increases, the timing belt and its accessories, such as timing belt tensioner, timing belt tensioner and water pump, etc. become more difficult. or age. Therefore, the manufacturer of any engine equipped with a timing belt will have strict requirements to replace the timing belt and accessories regularly within the specified time frame. The replacement period will vary depending on the structure of theengine. Typically, the vehicle will run for 6 hours. month. It must be replaced every 10,000 to 100,000 kilometers. The specific replacement cycle should be based on the vehicle service manual.
Baidu Encyclopedia - Timing Belt
What are the harmful consequences of high engine temperature?
Most abnormal belt noises from Pacific Automotive Network are due to the belt being loose. If this happens, it is best to go to the repair shop to adjust the belt tension because the belt is loose. will make a squealing sound if it slips. Once the belt slips, the belt will be further stretched due to friction and high temperature, making the slipping more serious and entering a vicious circle. Therefore, quick adjustment of belt tension is essential.
Most of the time, when the beltIt makes an abnormal noise, it's because it's loose. In this case, it is better to go to the repair shop to adjust the belt tension, because the belt will produce noise. a squeak if it slips. Once the belt slips, it will cause the friction temperature to be further stretched and slip more seriously, entering a vicious circle. Therefore, quick adjustment of belt tension is essential. If you have driven almost 20,000 kilometers and have never changed the belt before, you should normally replace the belt now. Don't wait for the belt to break before replacing it and you'll be in big trouble.
How to judge the abnormal noise of the engine belt: Step
First: If there is an abnormal noise in the engine compartment of the car, it is usually because the belt is loose or of poor quality. You must therefore first check the motor belt.tor. If there are multiple belts in the car and we cannot determine which belt is the problem, we can start the car first and then pour water on the belt. If the abnormal noise disappears, there is a problem with this belt. , and we will. You will be able to check if it is loose or of poor quality.
The motor belt makes an abnormal noise. Dousing it with water will increase its viscosity, which effectively improves the viscosity of the belt. But after the water dries, the belt will return to its original state. This is the principle of belt watering.
Step
Second: We can also judge by listening to the sound.Which belt is the problem? If there is an abnormal noise when the air conditioner is turned on, there may be a problem with the air conditioner compressor belt. If there is a problem with the steering wheel turning, there may be a problem with the pump belt.pe power steering. If the car makes abnormal noises when starting from cold, there may be a problem with the engine belt. We can check it step by step.
Diagnosis and solutions to abnormal engine belt noise faults: The engine belt squeaks: This is due to relatively mild wear of the joining surface of the belt and pulley. This usually happens when the engine speed changes quickly. Sometimes the increased load on belt-driven accessories also causes belt noise. If the belt makes a squealing noise, it usually means that the coefficient of friction of the belt surface has been significantly reduced and the belt is excessively worn. If the vehicle makes noise when loaded, you may want to observe one of the drive belts. You will find that the strength or elasticity of the automatic neck tension devicebelt tension will increase abnormally.
Most automatic belt tensioners have a set of belt wear length indicators somewhere between the bottom and arm of the tensioner, along the slide. The mark consists of a pointer and two to three marks that indicate the operating range of the belt tensioner. If the pointer is outside of this range, the belt is probably too tight and needs to be replaced. On vehicles without an automatic belt tensioner, use a standard belt elongation tape measure halfway between the two pulleys. If there is a difference from the standard value, it is best to replace the belt.
Long squealing or squealing noises from the engine belt: Although the pulley surface is stained with dirt such as sand or the worn belt is installed upside down, the belt will also emit longgs squeaks or squeaks. noises. This is generally due to incorrect mounting of the auxiliary device. If the noise occurs in a new car that has been on the road for some time, it may be caused by poor quality original equipment.
1. Engine power decreases.
When the car runs at a temperature above 35°C, under wind or with a heavy load and low speed, the engine overheating becomes more serious, further reducing the inflation coefficient of the engine, resulting in a reduction in the amount of fresh mixture entering the cylinder, and the average cylinder effective pressure decreases and engine power decreases.
2. Fuel consumption increases.
When the engine temperature is too high, the lubricating oil leaking into the cylinder will easily form colloidal coke under the condition of high temperature and lack of oxygen. Coke will build up onthe top of the piston, on the wall of the combustion chamber. valve top and spark plug, forming hot spots, triggering hot ignition in the engine, resulting in abnormal combustion, which can easily cause deformation or even cracking or deformation of the engine block and cylinder head, and also easily burn the cylinder gasket, resulting in a drop in cylinder pressure at the end of compression and an increase in fuel consumption.
3. Mechanical parts are worn.
Lubricating oil will oxidize and deteriorate due to excessive temperature. Colloids and sediments will adhere to the friction surfaces of piston rings, cylinder walls and other parts, reducing thermal conductivity. The viscosity of the lubricating oil decreases, the oil pressure decreases, and the lubricity worsens. The resistance of the oil film on the cylinder wall isweakens under the influence of impact load, thereby worsening the wear of machine parts.
Detailed information:
Overheating the engine will cause a series of vehicle failures, and the cooling system will be the first to suffer. Excessive engine piston temperature will also cause cylinder lock failure. Additionally, the lifespan of seals and some internal parts will be significantly reduced. Starters, generators, regulators and other external equipment can also be easily burned and discarded.
In order to prevent the engine temperature from becoming too high, regular vehicle maintenance is necessary. First of all, it is necessary to keep the exterior of the cooling system clean. Next, the vehicle's water tank and antifreeze must be cleaned. sufficient. Finally, he isIt is not necessary to prevent the engine from running under heavy load if it lasts too long, this can effectively avoid unnecessary trouble and improve driving safety.
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