Can the four circuit adjust the air pressure, and what is the principle of the four circuit protecti

The truck changes to a dry bath bottle assembly, and the four-circuit can only play 6 air pressures?

The dried gas is divided into 4 circuits to meet the needs of different systems of the vehicle, including service brake system, parking brake system, air suspension system, door control system, etc., and at the same time ensure that when a circuit fails, other circuits can work normally, and the air pressure of the failure circuit can be appropriately supplemented.

The opening pressure of the protection valve is MPa, and the closing port pressure is MPa.

The compressed air from the pressure regulator through the separator enters the protection valve from the "1" port, and when the inlet pressure is low, the valve seat is closed under the effect of spring 5, and the inlet pressure acts on the valve center area "a". When the inlet pressure rises to megapascals (bar), the air pressure acting on the area "a" produces an upward thrust sufficient to overcome the pre-pressure of spring 5. The valve began to rise, opening the channel for inflating the circuit "2".

Because the valve is made of throttling form, the valve does not open when it is closed and opens during the inflation process to the circuit, which prolongs the service life of the valve. With the continuous inflation to the circuit, the loop air pressure acts on the annular area "b" of the valve, so with the continuous increase of the loop air pressure, the opening pressure of the inflation continues to decrease, until the loop air pressure reaches the megapascal (bar), the megapascal (bar) air pressure on the entire area of the valve produces the top force of the valve and the spring pre-pressure is equal, at this moment the valve is officially opened, and the opening of the valve increases with the increase of the loop air pressure. When the air pressure of the circuit is reduced to MPa (bar), the valve is closed again.

Therefore, MPa (bar) is the opening pressure of the protection valve, and MPa (bar) is the closing pressure of the protection valve. When four of these valves are combined, it is a simple four-circuit protection valve.

Protection valves can be divided into double-loop, four-loop, and multi-loop protection valves from the structure and function.

How it works:

The dried gas is divided into 4 circuits to meet the needs of different systems of the vehicle: service brake system, parking brake system, air suspension system, door control system, etc., and at the same time ensure that when a circuit fails, other circuits can work normally, and the air pressure of the failure circuit can be appropriately supplemented.

A combination of a regulator and a diverter valve to divert air pressure and safety pressure.

The whole vehicle gas circuit is divided into four circuits that are both interconnected and independent of each other, and when any circuit fails, it does not affect the normal operation and inflation of other circuits.

The function of the four-circuit protection valve: the whole car gas circuit is divided into four interconnected and independent circuits, when any circuit fails (such as broken, leakage), it does not affect the normal operation and inflation of other circuits. Under normal circumstances, the four-loop protection valve is actually a five-way joint, which only plays a protective role when a circuit is broken or leaked.

The common faults are mainly as follows:

1) If a pipeline is not ventilated or leaks, check whether the four-loop protection valve and check valve are stuck or the diaphragm is broken. The main reasons for these failures are: the airway contains a large amount of water, and the inner cavity produces a large amount of rust, which jams the air valve and sheds the corroded foreign matter.

Causes the diaphragm to rupture and cause air leakage.

2) The imbalance of air pressure is relatively rare, because the standard air pressure of the four-circuit protection valve has been adjusted before leaving the factory, and all the imbalance faults are maintained and replaced with internal accessories.

Principle: Under normal circumstances, the four-loop protection valve is actually a five-way joint, and only when a certain circuit is broken or leaked, it will play a protective role.

Function: When one circuit in the gas braking system fails, the four-protection valve can make the inflation and air supply of the other circuits not affected. The four-circuit protection valve divides the whole vehicle gas circuit into four interconnected and independent circuits, and when any circuit fails (such as broken or leaked), it does not affect the normal operation and inflation of other circuits.

Principle: Depending on the application, four circuits are connected in parallel, and the air pressure is charged at the same time, or the circuit is inflated before the circuit. Some models have a four-circuit protection valve with a bypass hole in all circuits to ensure that if one circuit fails, the braking system is inflated from 0 bar.

The compressed air from the regulator enters the four-circuit protection valve through one port and the four circuits of the system through the bypass holes (A, B, C, D) and the check valve (H, J, Q, R).

At the same time, the pressure is also established under the valve (g, k, p, s), and when the set opening pressure (protection pressure) is reached, the valve opens and the diaphragm (f, i, o, t) again overcomes the spring (e, m, n, u) force and bulges.

Then compressed air flows into the 1 circuit air reservoir and 2 circuit air reservoir of the service braking system through the port, and enters the circuit through the port. The 3rd circuit supplies air to the truck's emergency braking and parking brake system, and also provides an air source for the trailer. The 4th circuit supplies air to the auxiliary braking system.

If one circuit of the service brake fails (e.g., Figure 1), air from the other three circuits leaks out of the failed circuit until a dynamic shut-off pressure is reached. The spring force causes the valve (e, m, n, u) to close.

If there is a leak of air in the circuit, it will be charged again until the set opening pressure of the failure circuit is reached. If the other circuits fail, the pressure protection process for the intact circuits is carried out in the same way.

In addition, if one circuit fails (circuit 1) and the air in the intact circuit drops to 0 bar for any reason, when the braking system is reinflated, the compressed air first enters all four circuits through the bypass holes (a, b, c, d). Compressed air from the air compressor is stored.

Uses: In the four-circuit braking system, if one or more circuits fail, the brake air pressure of the intact circuit can be maintained.

First of all, the protection valve can be divided into double circuit and four circuit and multi-circuit protection valve from the structure and function, generally he is divided into 4 circuits after drying, to meet the needs of different systems of the vehicle, such as service brake system and parking brake system and air suspension system and door control system, etc., it also ensures that when a circuit fails, other circuits can work normally, and the appropriate failure circuit air pressure is supplemented.

A four-way valve is a four-way valve? no！The principle of automobile pneumatic brake four-circuit protection valve.

If the air pressure of the air reservoir is too low, and the pressure of the dryer outlet is not low, check whether the four-circuit protection valve is broken. The low pressure alarm switch is installed in ** and will not affect the pressure of the gas reservoir.

A special tube is connected from the gas cylinder to the sub-pump

It could be an issue with the clutch fork.