What should I do if the semi trailer gas circuit freezes and the brakes do not return

What should I do if the truck freezes when the air brake freezes in winter?

When we find that the air brake is frozen, we can turn on the engine and idle for ten minutesUse the heat of the engine to thaw the air brakes, and then try pouring hot water on the brake calipers if there is hot waterWait for the ice on the caliper to thaw before trying to see if the air brake can be turned on.

Generally speaking, the air brake of the truck is equipped with an air dryer, if the dryer is damaged, the probability of the air brake being frozen will be greater, and there will be a water outlet valve under the air tank, we should open the water outlet valve once a month to discharge water, so as to avoid the air brake being frozen.

Air brake master cylinder broken symptoms:

Sudden brake failure: If the car feels like it suddenly fails for a moment when braking, you need to observe the brake fluid.

If there is no loss, then check whether there are traces of brakes in the air brake master cylinder, sub-cylinder and oil pipe. If there is, it means that the brake master cylinder or sub-cylinder has a serious oil leak.

Brake misalignment: If you feel that the brake direction is off, it is likely to be caused by the expansion of a piston in the air brake master cylinder, and of course, it may also be caused by uneven brake wear.

Soft brakes: When we step on the brakes, if we feel that the texture of the brakes is obviously soft, and the stability of the continuous brakes is reduced, it may be that the piston seal of the air brake master cylinder and sub-cylinder is poor, or the brake pipeline is broken somewhere, resulting in oil leakage.

The method of thawing the brake valve of the semi-trailer in winter is: using the idle speed of the engine of the vehicle to thaw the brake valve of the car can solve the situation that the brake valve is frozen in winter.

With the advent of winter, it is difficult to reduce the temperature drop, the sealing ring or gasket, in the summer wind and rain, the synthetic seal is getting worse and worse, especially the shaft tube joint above, the low temperature in winter causes the sealing tube to shrink the joint, and the leakage sealing performance difference, so be sure to check each joint to seal the gas channel before pumping the car in the morning.

Check the dryer tank of the main vehicle to ensure that the air source of the main vehicle is dry and free of moisture. Since the drying tank is an air filter, it loses the filtering effect of residual water vapor from compressed air with the extension of use.

The compressed air does not achieve the purpose of drying, causing the water in the pipeline and valve body to freeze, which affects the normal use of the brake.

There's a spring in the air chamber, five air pressures don't move, eight air is just balanced, I'm talking about double air chambers.

If the brake on the road is frozen, there is only one way to unload him There is boiling water with boiling water There is no boiling water with a blowtorch to heat it simply, don't bake the pipe If you don't solve it, it is easy to cause bad brakes, or brake death! Remember.

This should be caused by too much moisture or frost, I hope it can help you.

The principle of the air circuit of the braking system of a semi-trailer car: it creates a huge frictional force that converts the kinetic energy of the vehicle into heat. As we all know, energy is neither generated nor disappeared from space.

It can only be converted from one form to another or from one object to another. During the transformation or transfer, the total energy remains the same.

During the acceleration process, chemical energy is converted into heat energy and kinetic energy. When braking, the braking system converts kinetic energy into heat energy and discharges it into the air.

Nowadays, most small cars use hydraulic braking, because the liquid can not be compressed, almost 100% of the power can be transmitted, the basic principle is that the driver presses the brake pedal, the brake oil is applied in the brake main cylinder, and the liquid is piped to the piston of each wheel brake caliper, and the piston drives the brake. Car brake calipers clamp the brake discs, causing huge friction and slowing down the vehicle.

Propelled with air. Also called air brake. There is a small air compressor in front of the engine to pump up. There are two brake shoes in the hub of a wheel, and there is a camshaft in the middle of the two brake shoes.

Main car air pump, air dryer, main car air storage, throttle valve, four-point valve (usually called trailer valve) divided into main car and trailer, if the brake is too good, you can add a throttle valve or brake king

Brake master cylinder "throttle" trailer valve "main car brake cylinder

Trailer valve》trailer air reservoir (the front dryer must be replaced when the water discharge valve is opened with water and oil) > brake cylinder

The parking brake is pulled up, the trailer valve, and the sub-pump

Each sub-cylinder "gas intake" launched "camshaft rotation to drive the pulley", "brake pad", "friction brake loose brake", "sub-cylinder return part" trailer valve

Handbrake loose "exhaust" trailer return gas.

The vehicle brake is divided into three parts: front brake, rear brake, trailer brake. These three parts are divided into different air path controls.

Master cylinder: The brake control starts when we press the brake pedal, and the master cylinder converts the foot braking force into an air pressure control signal, which is divided into two air paths: the front brake and the rear brake.

Relay valve: similar to relay, it controls the atmosphere through small gas, shortens the length of the braking gas path, and ensures speed and air pressure.

Sub-Pump: Converts the air pressure into the thrust of the rotating cam, which generates braking force.

Trailer valve: the structure is **two out,**: the air reservoir is often fed, the front brake control gas, the rear brake control gas, and the hanging brake control gas. Two out: trailer control gas (yellow pipe), trailer often gas (red pipe).

The function of the trailer valve is to transmit the brake control gas signal to the trailer according to any one of the three signals of the front and rear brakes and the trailer brake.

The principle is that the air pressure from the residence is on the brake valve, and the brake valve pressurizes the trailer cylinder, which is to increase the air pressure.

To understand the principle of trailer brakes, as well as the common sense of trailer maintenance, or go to China's most professional trailer information ** "Trailer Home" to understand.

First of all, it is excluded whether the trailer is leaking, if the air leakage is too fast, it will be like this, if it is serious, it will not be able to lift the handbrake. Generally, the trailer valve is leaking, and then there is a filter screen on the relay valve, which will also occur if it is blocked. Hope it helps.

It should be that the brake air control distribution valve is broken, go to the maintenance point to replace one, it is not expensive. About two or three hundred. Hope it helps.

Take a look at whether the brake pipeline and sub-pump are good, especially the sub-pump and sub-pump of the semi-trailer, whether there is air leakage, or the phenomenon of inflating does not enter, whether the sub-pump is leaking, whether it is working well, and whether the main pump and main pipeline of the tractor are working normally!

It should be said that it is a problem of your four-circuit or six-circuit separation, you can change one or reverse the pipe head.

Changing the trailer valve is pretty much the same.

The brake chamber is connected with the camshaft and adjustment arm of the brake, and the brake is engaged and separated under the action of air pressure.

The brake chamber is divided into two types: diaphragm type and piston type.

In general, the front brakes of tractors and trailers of medium-sized automobile trains are commonly used diaphragm brake chambers, while the rear brakes of tractors and trailers use piston brake chambers with spring brake chambers.

See the attachment for details.

The barometric gauge hand one is six, and one is を

What's wrong **Runaway, let's talk about it.

From the air pump to the dryer, the dryer is divided into four silver air circuits, and each air reservoir is distributed, and each brake pump has at least one connected to the gas reservoir.

That's more. I want to know that I understand everything under the climb.

What is the structure of the whole vehicle gas circuit of the Dongfeng Longka semi-trailer?

Disassemble the control trachea on the relay valve and try it first... Be cautious 、、、 if you are locked up??? The master cylinder is disassembled and wiped with grease.