The railway braking system belongs to the technical field of rail brakes fixed to the railway line. The invention is provided with a brake supply pump in turn along a train slip direction near the track end line of the railway marshalling yard, sequential valve, reversing valve, wheel pressure delay reversing valve, side pressure delay reversing valve, braking mechanism, wheel pressure delay reversing valve, Railway Brake System for unloading one pump valve, which is communicated through the pipeline and the check valve. The method is adaptable, safe and reliable, and the operation efficiency is high.
Characteristics of railway braking system
The EMU running speed will give a series of problems to the braking ability and running smoothness of the train. (because the train braking energy and speed of the square is proportional, the speed of 200km above the EMU's braking energy is the ordinary train more than 4 times times.) Therefore, Railway Brake System the performance and composition of the railway braking system is completely different from the current passenger train in China.
High-speed EMU must be equipped with high efficiency and safety of the railway braking system, for the normal operation of the train to provide speed and parking brake means, and in the event of unexpected failure or other necessary conditions with the shortest possible braking distance. Generally speaking, the railway braking system of EMU should have the following characteristics:
First, high safety
The braking ability of high-speed railway braking system is strong, Railway Brake System the reaction speed is fast, and it has a high safety; the structure is embodied in the following two aspects:
(a) The use of electric and air joint braking mode, electric braking priority, and generally equipped with anti-skid device. The combination of electric braking and air braking can ensure that the train has sufficient braking force in the larger speed range, and the installation of the Antiskid device can make the adhesion of the wheel and rail to be fully utilized, Railway Brake System thus shortening the brake distance effectively. The electric braking is easy to control and can greatly reduce the abrasion of the parts of the air railway braking system, thus it is preferred to use.
(ii) control the use of electronic control, direct or microcomputer control electrical instructions such as sensitive and rapid system. These devices make the railway braking system react more quickly and further shorten the braking distance.
II. Accurate control
The braking action adopts the microcomputer control, which can provide the necessary braking force precisely to ensure the train punctuality, and the model of the compound braking is designed rationally so that the braking force of different type can achieve the best combination effect.
Third, high degree of comfort
The time and speed of the braking action of high-speed EMU are much higher than that of ordinary passenger trains, so the corresponding measures are taken to improve the longitudinal comfort of passengers, Railway Brake System and the average speed of braking, the maximum speed of reduction and the longitudinal impulse are more than that of ordinary passenger trains. The measures taken include:
(a) using the microcomputer-controlled electric-command railway braking system can realize the optimal control of the braking process, and reduce the rate of change of the reduction speed while increasing the average reduction speed;
(b) Reducing the difference in vehicle braking power in trains to mitigate the longitudinal impact between vehicles.
(c) Anti-skid device can also avoid the lack of adhesion between wheel and rail to produce wheel tread abrasions, and then prevent the smooth running of the train deterioration, Railway Brake System improve ride comfort, and avoid the axle and other components to produce additional stress problems.
IV. High Reliability
(i) Use the "fault-oriented safety" mechanism (fail-safe) to move in a safe direction in the event of a railway braking system failure.
Such as high-speed EMU is generally equipped with air braking, computer-controlled electro-pneumatic braking and computer network three kinds of braking control methods. Under the normal operation condition, the computer network control and transmit the braking information of the whole train vehicles. When the control system fails, Railway Brake System it can automatically switch to the electro-cavitation braking effect. In the case of electrical failure or electro-pneumatic braking failure, it can rely on pure air braking to ensure the braking distance under bad condition.
In addition, a large number of information input, digital operation and output instruction are needed in the braking control process of the high-speed EMU microcomputer control, Railway Brake System in order to prevent the fault, the corresponding reliability measures are also considered in the design of the instruction system.