Why does the truck make a deflated sound before it starts?

When we were young, whenever we saw the sound of air released by large trucks, we thought it was a flat tire, and when we grew up, we knew that it was not an air leak, but a big deflating sound when the big truck braked, where did this sound come from?

The main brake used in large vehicles is the shut-off brake, also known as the energy storage shut-off brake, energy storage spring brake, which is the parking brake of the car.

in one of the forms. The sound of deflation is actually the manifestation of car brakes.

The popular explanation is that there is a strong spring in the brake chamber, and the compressed air will push the spring up when driving; Braking is to release the gas and let the spring lock the brake; When the air pressure in the car is too low, it will also have a braking effect to ensure safety. The regular brake is the handbrake.

Lock the propeller shaft.

When braking, the wheels are locked by compressed air entering the brake chamber. In the event of mechanical failure of the handbrake or propeller shaft, the handbrake fails; in the air compressor.

When any part of the pipeline, air reservoir and brake valve fails, the service brake fails. The shut-off brake can effectively avoid these dangers. Even if the air is cut off, it can also be braked to ensure driving safety, in the service brake.

When the air compressor fails or the compressed air pressure is insufficient, the wheels can be braked to ensure the safety of the vehicle.

Exhaust braking, as it is commonly called, is to turn the engine, which was originally a power take-off device, into an air compressor, and become a power-consuming device. First of all, when the exhaust brake is activated, the fuel injector will stop injecting fuel (only for the national III engine of EFI, many old national II engines will continue to supply fuel), but the engine still works, constantly inhaling fresh air, and at the same time the butterfly valve installed in the exhaust system is closed, blocking the exhaust manifold, so that the pressure in the exhaust manifold reaches 4-6 atmospheres.

At this point, the engine's power source is the inertial force of the vehicle that continues to coast.

Instead of the energy generated by the combustion of the mixture, the engine piston is compressing the high-pressure air in the exhaust pipe at this time, constantly consuming the kinetic energy of the vehicle to achieve the purpose of slowing down the vehicle.

Generally, the weight of the car is not very large, that is, the appearance of a few tons, in contrast, the weight of the large truck is dozens of tons at every turn, sometimes the goods carried are too heavy, and the overall weight of the car will increase a lot, so if the large truck uses the brakes of the car, the brakes will be very hard, and they cannot be stepped on at all.

In order to solve this problem, people invented the air brake system, which is the task of stepping on the brake and transferring it to the high-pressure gas, and the foot plate of the brake is only responsible for adjusting the pressure of the air pressure chamber.

When the car is started, the compressor will continue to compress the air into the cylinder, and when the brakes are pressed, the air will be turned on, and the air pressure will quickly enter the brake pipe under the action of pressure, and the brake disc will be affected.

Carry out the action. After the braking process is completed, the piston will return to its original position under the action of the spring, and at the same time will do the work.

The gas in the pipes is quickly discharged, so we will hear a popping sound.

This is because the truck is letting go of the handbrake, because the truck's handbrake is an air brake, so when we are in front of the drive, we will hear a deflated sound.

It may be because the front wheel carrier or ball joint of the car is damaged, so there will be a sound. Or maybe it's because the car's air conditioner is out of order.

It was the sound of compressed air, exhaust. Because of the large weight and great inertia of large trucks, they need a lot of braking force when braking, and it is very difficult and unsafe to rely on manpower alone, so large trucks use air brakes.

Because the truck is very heavy, there is such a sound, the start is relatively slow, which is a very normal phenomenon, but after a period of time to refill the tires of the car, and to check the parts of the car.

This is because trucks use air brakes, which release air when the brakes are applied, and air pressure is released when the pressure reaches a certain level. Because the gas is relatively full, this sound is often heard.

That's because large trucks or buses use air brakes, which release air when the brakes are applied. After a certain amount of pressure, air pressure is also released. That's why you're going to hear it a lot.

Because most trucks use air brakes, when the pressure reaches a certain level, it will automatically deflate to release the pressure, which usually occurs when it starts again after braking.

The gas tank is not full and there is a leaking sound, but the pressurized gas is not down, and the brake tank is not less gas

Summary. Dear, I am glad to answer for you that the car has a deflated sound is the solenoid valve is a high-pressure gas at one end, and a low-pressure end at the other end, when the solenoid valve is opened, the high-pressure gas quickly passes through the valve, which will produce a very high deflating sound.

When driving normally, you can hear the sound of deflating in front.

There will be a little bit every once in a while.

Dear, I am glad to answer for you that the sound of the car has a good fortune to let the hood deflated is the solenoid valve at one end is high-pressure gas, one end is the low-pressure end, when the solenoid valve is opened, the high-pressure gas quickly passes through the valve, which will produce a very high slippery deflating sound.

It's normal. This situation may be caused by poor friction of the car's brake pads.

If you hear the sound of deflating, it means that there is basically no big problem with the opening of the core, especially in the summer when the temperature is too large, because the temperature difference between the inside and outside is too large, and the temperature of the gasoline rises and the internal pressure increases, so it is normal for the gas to leak out early when the fuel tank cover is opened.

Well, what is that tire that feels like there is a rattling sound all the time, and the tread may be mixed with pebbles. If the tires are deformed, you need to replace them. When the stone gets stuck, pick it out.

If it is a low "pop" sound, it is most likely that the tire tread is deformed, bulging, severely worn or has insufficient air pressure. The brake disc is mixed with tiny stones, which causes abnormal friction during driving. Due to lack of oil or fatigue wear, etc., the wheel is cut off and the tire bearing is abnormal and weared.

The main material of brake pads is heavy metal, and there will be hard metal spots, which may make abnormal noises during driving. The brake pads are badly worn, and the brake pad backplate is made of metal, which will make abnormal noises during operation.

It is similar to the sound of hitting the steering wheel on the rubber floor.

Tire rubbing against the ground. If you hit the steering wheel in place, the steering wheel will rub against the ground and make noise. This is very normal, and it will be more ruined and noticeable on the floor painted; The steering column lacks lubricating oil.

The steering column is an important part of transmitting the steering action, and after using it for a period of time, the steering column will lack lubrication, and there will be friction sound at this time; Failure of the airbag hairspring. If the noise comes from the steering wheel, it proves that there may be a problem with the airbag hairspring; Shock absorber plane bearings are damaged. If the sound of rubber rubbing is coming in from the engine compartment, then we can check the flat bearings of the shock absorbers.