RU2775892C1 - Method for control of density of train brake line - Google Patents

Abstract

FIELD: railways.

SUBSTANCE: invention relates to the control and testing of braking systems. A method for the control of density of a train brake line consists in that an air speed in a pipeline is measured by ultrasound sensors, and reduced mass flow of compressed air coming from a machinist crane or a brake control system to the train brake line is determined. At the same time, means of the control system or locomotive safety calculate and register indicators of volumetric and mass flow of compressed air, using readings of sensors of pressure and compressed air temperature, mounted in this system. After that, the indicator of compressed air flow is compared with previous registered values, and a conclusion is made according to detected changes in flow value about change in density of the train brake line.

EFFECT: increase in the safety of train movement.

1 cl

Description

The invention relates to the diagnosis of traction rolling stock of railways and is intended to control the density of the brake line of the train.

The consumption of compressed air from the brake line of the train is an important diagnostic tool for monitoring the state of the brake system of the rolling stock. At present, the check of the density of the brake line is carried out precisely by the consumption of compressed air, in accordance with table IV. 1 of Appendix 2 of the Rules for the maintenance of brake equipment and control of the brakes of railway rolling stock, which contains the time standards for reducing pressure in the main tanks by the amount of the established differential, for various volumes of the locomotive GR and the length of the train. Essentially, as an indicator of air consumption, time is given depending on the number of cars in the train and the amount of air to replenish leaks. The method used is very laborious, the number of cars is given with a measuring range of 50 axles, which reduces the accuracy of the check; measurements are made manually, with a high density of the train brake network, the process of determining and controlling the density takes a long time; in addition, the adopted method does not allow determining a separate indicator of the density of the composition of cars.

There is a known method for determining the actual volume of the pneumatic feeding networks of the locomotive (patent RU 2252884 C2 V60T 17/22, publ. 27.05.2005), based on the comparison method. According to this method, after determining the consumption of compressed air for leaks from the pneumatic networks of the locomotive by the estimated volume of the main tanks by the time the pressure decreases by the value of the established difference, an atmospheric throttle of known diameter is connected to the constant pressure line at the outlet of the driver's valve. The consumption of compressed air for leakage from the pneumatic networks of the locomotive is determined in the presence of an artificial leakage from the atmospheric throttle. By comparing the obtained results, the actual volume of the locomotive's pneumatic feeding networks is determined.

The disadvantage of the known method is that it is used to control the brake network by the consumption of compressed air from the main reservoirs, which does not allow to determine the integrity of the brake line of the train, to identify the overlap of the end valves in the train, which leads to a loss of braking efficiency and adversely affects traffic safety. trains. Also, the disadvantages of this method include the low accuracy of density determination, which depends on the determined volume of the main tanks, and depending on the compressed air consumption, has significant errors even with slight changes in the pressure drop time.

Also known is a method for controlling the density of the brake network of a train by determining the length of the brake line of the train and the number of cars included in the brake system (patent RU 2725834 V60T 17/22, priority of the invention from 08/22/2019). This method is based on measuring the rate of pressure reduction in the brake line after its additional discharge caused by the short-term opening of the end valves and the operation of the air distributors, as well as after connecting an additional leak to the brake line, with a flow rate of a known value. Further, the length of the brake line of the train is determined by the ratio of the obtained rates and the specific volume of the brake line.

All of the above methods, as well as many others, are based on monitoring the density of the brake line by measuring the pressure in the supply line (main tanks) of the locomotive or brake line, and have disadvantages due to the very principle of diagnostics. When measuring the pressure (and the rate of its change) in the supply line, it is impossible to take into account all additional sources of compressed air consumption located on the locomotive and significantly affecting the accuracy of determining the density of the brake line of the train. To eliminate the influence of additional sources of compressed air on the measurement accuracy, it is necessary to limit the density control, exercising it only in steady-state modes (train parking or movement in the "run-out" mode, provided that sound signals and sand are not used). When measuring the pressure (and the rate of its change) directly in the brake line, to determine the conditional length of the train, it is necessary to trigger the brakes, which makes this control method possible to use only at the train stop, at the request of the locomotive crew.

The technical task of the invention is to create a method for controlling the density of the brake line of a train, free from the above disadvantages, which controls by determining the flow rate of compressed air coming from the brake line of the locomotive into the brake line of the train, to replenish leaks and maintain charging pressure in the brake line of the train.

EFFECT: increased safety of train traffic by monitoring the state of density and integrity of the brake line of the train, detecting ice plugs or closing the end valves in the train, by determining the change in the relative value of the compressed air consumption.

To solve the problem and achieve the technical result in the method for controlling the density of the brake line of the train, based on measuring the flow of compressed air in the brake line, according to the invention, the flow of compressed air coming from the brake line of the locomotive into the brake line of the wagon train is determined continuously in conventional units and by changing this indicator up or down, a conclusion is made about the corresponding change in the density of the brake line of the train.

An increase in compressed air consumption indicates the appearance of additional leaks in the brake line, and, consequently, the occurrence of such failures as a break or break in the brake line, a break in the supply pipeline or disconnection of the connecting sleeves. A decrease in compressed air consumption indicates a reduction in existing leaks in the brake line, which means the occurrence of such failures as freezing of the line with the formation of an ice plug in the pipeline, or closing of the end valves, as a result of which part of the brake line is cut off from the pneumatic connection with the brake line of the locomotive, and, consequently, the leaks existing in the disconnected part are also cut off. Thus, the possibility of qualitative control of the density of the brake line, the integrity of the brake line and the detection of the overlap of the end valves in the train is realized, which ensures an increase in the safety of train traffic.

The essence of the method for controlling the density of the brake network of the train is as follows:

It is impossible to install tachometric, vortex, thermometric, hot-anemometric flowmeters, or flowmeters of differential pressure in the brake line, since the principle of operation of these types of flowmeters is based on changing the flow area of the pipeline, which is unacceptable for safety reasons (it is forbidden to change the section of the brake line, as well as to place any elements in its working section in order to prevent deterioration of the compressed air permeability). It is not advisable to install an ultrasonic flow meter as a finished technical product, since all the necessary measuring elements of the density control system, with the exception of ultrasonic sensors, are already on the locomotive as part of the control or safety system. Duplicating components will only complicate and increase the cost of the control system.

Therefore, two ultrasonic sensors are installed in the brake line of the locomotive (each performs the function of both a transmitter and a receiver) to determine the speed of the compressed air passing inside the line. The sensors are installed on the section of the brake line of the locomotive, after the driver's crane (or the brake control system that performs the functions of the driver's crane, such as UKTOL or TOL). Ultrasonic sensors are installed in the brake line opposite each other in such a way as not to change the flow section of the line in any way (flush to the pipeline). Ultrasonic sensors determine the speed of air movement in the brake line pipeline according to a well-known principle (the speed of the signal from the transmitter to the receiver will change every time the air moves; if the ultrasonic signal goes in the direction of the air flow, then the time decreases, if against - increases; by the time difference signal passing upstream and downstream and the air speed is calculated) and continuously transmit information to the control system of the locomotive. Further, according to the well-known formula:

Q=60π⋅r ² ⋅v,

where Q is the volume flow of compressed air; r is the inner radius of the pipeline; v - air speed, the current volume flow of compressed air is calculated in the microprocessor control system of the locomotive. Then, using the data from the pressure and temperature sensors of the compressed air in the brake line, the control system calculates and normalizes the mass flow of compressed air. All calculations are made according to well-known formulas.

Thus, the control system (or safety system) of the locomotive continuously determines and registers the reduced mass flow rate of compressed air going into the brake line of the train. And the control of the change in this indicator makes it possible to timely detect the corresponding failure of the brake system of the train, associated with a change in the density of the brake line, thereby continuously ensuring traffic safety in any operating modes of the locomotive and the train as a whole.

Claims (1)

A method for controlling the density of the brake line of a train, based on measuring the speed of air movement in the pipeline with ultrasonic sensors and determining the reduced mass flow rate of compressed air coming from the driver's crane or the brake control system into the brake line of the train, characterized in that when measuring the speed of compressed air in the brake line by means of ultrasonic sensors, the calculation and registration of indicators of volume and mass consumption of compressed air is carried out by means of the locomotive control or safety system using the readings of pressure and temperature sensors of compressed air installed in this system, after which the indicator of compressed air consumption is compared with the previous recorded values and according to the detected changes in the flow rate, a conclusion is made about a change in the density of the brake line of the train.