RU2296686C1 - Method of diagnosing condition of elements of rail bonds - Google Patents

Abstract

FIELD: railway transport; signaling and communication.

SUBSTANCE: invention provides possibility of diagnosing condition of bond elements by carrying out additional operations. At additional measuring of currents in main and doubling rail bonds, relative values of current in each rail bond are calculated by dividing product of value of current passing through corresponding bond and specific resistance of rails to current by voltage drop on one meter of solid rail. Relative value of current passing through rail fishplates is calculated by subtracting from unity the sum of current in rail bonds multiplied by specific resistance of rails and divided by voltage drop on one meter of solid rail. By comparing found relative values of current in rail bond elements with tolerable values conclusion is made on condition of elements whose current value is less than tolerable value.

EFFECT: improved accuracy of measurements.

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Description

The invention relates to railway automation and telemechanics and can be used in the maintenance of rail chains.

A known method for monitoring the state of conductive joints, according to which the resistance of the controlled joint and the resistance of one meter of solid rail is connected to the two shoulders of the measuring bridge, balance the bridge by changing the ratio of resistances in the other two shoulders of the bridge and the ratio of the resistances in these two shoulders, after balancing the bridge, determine - how many times the joint resistance is greater than the resistance of a section of a whole rail one meter long [1]. This method is inconvenient for mass control of the resistance of conductive joints and does not make it possible to isolate a faulty element in a faulty joint - one of the butt connectors or plates.

There is also a method of two voltmeters, when the voltage drop is measured from the traction and / or signal current at a conductive joint and on one meter of a solid rail, and then, knowing the specific resistance of the rails to the electric current flowing through them, the ratio of the resistance of the conductive joint and one meter of solid rail [2]. This method is much more convenient for practical applications, however, and it does not allow to diagnose which element is faulty.

The aim of the invention is the ability to diagnose which of the elements of the conductive joint caused its malfunction: one of the butt rail connectors or plates.

This is achieved by the fact that in order to ensure the process of diagnosing the state of the elements of the conductive joint, the currents in the main and duplicate butt rail connectors are additionally measured, the relative current values in each connector are calculated by dividing the product of the current through the corresponding connector and the electrical resistivity of the rails to this current by the voltage drop on one solid rail meter, calculate the relative value of the current through the rail lining by subtracting from the unit the sum of the currents in spike connectors, multiplied by the electrical resistivity of the rails and divided by the voltage drop per meter of a solid rail, and then comparing the found relative current values in the joint elements with their permissible values, make a conclusion about the malfunction of those elements whose relative current values are less than their permissible values .

The drawing shows the distribution of currents in the elements of the conductive junction and the measured voltage drop.

The current I _r in the rail 1 when flowing through the conductive junction 2 is divided into the current I _n in the plates 3, the current I _cc1 in the main butt connector 4 and the current I _cc2 in the redundant butt connector 5. To implement the proposed method for diagnosing the state of the elements of the conductive junction it is necessary to measure voltage drops at the junction U _c and on the continuous rail segment U _{o of} length l _o , as well as the current I _cc1 mainly and the current I _cc2 in the duplicate butt connectors. Voltage _drops can be measured with millivoltmeters, and currents I _cc1 and I _cc2 can be measured with _clamps .

If it is necessary to diagnose the state of the elements of the conductive rail joint, the length l _o = 1 m of the solid rail segment is measured, on which the voltage drop U _o will be measured, and also according to the type of rail 1, the numerical value of the rail specific resistance z _p , Ohm / m

Then the voltage drops are measured: U _c at the junction 2 and U _о on the solid meter length of one meter long, as well as currents I _cc1 - in the main butt rail connector 4 and I _cc2 - in the redundant butt rail connector 5. Current I _n in overlays 3 is based on the results of calculations.

In accordance with the types of the main 4 and redundant 5 rail butt connectors used, they are specified by the normative relative values of the current distribution in the rail I _p over the elements of the conductive joint:

- относительное нормативное значение тока в накладках;

- the relative standard value of the current in the plates;

- относительное нормативное значение тока в основном стыковом соединителе;

- the relative normative value of the current in the main butt connector;

- относительное нормативное значение тока в резервном стыковом соединителе;

- the relative normative value of the current in the backup butt connector;

The measured voltage drop at the junction is proportional to the junction resistance Z _c :

and the measured voltage drop on the rail with a fixed length l _about = 1 m:

The ratio of these stresses:

.Where

.

Therefore, the ratio of voltages U _c and U _{o is} proportional to the value of the resistance of the conductive joint Z _c . The numerical values of the electrical resistivity of the rails z _p and the length l _o = 1 m of the section of a solid rail on which the voltage drop is measured are known.

Therefore, the actual current resistance of the conductive junction from (3):

позволяет судить, исправен или нет стык. Если стык неисправен, для определения того, какой элемент стыка неисправен, выполняют следующие операции.Comparison of the found resistance value Z _c with its permissible upper value

allows you to judge whether the joint is working or not. If the joint is faulty, the following operations are performed to determine which joint element is faulty.

According to the measurement results, the current in the rail is calculated:

Then the relative actual value of the current in the main rail connector:

the relative actual value of the current in the backup rail connector:

relative actual value of current in overlays:

The calculated relative values of the currents in the elements of the rail joint are compared with their corresponding standard values. Faulty is the element whose actual relative current value is less than the standard, that is, the actual electrical resistance is greater than the standard.

Thus, the proposed method allows the use of several additional measuring and computational operations to diagnose the state of the elements of the rail conductive junction. The proposed method, in fact, is a non-destructive method for monitoring the state of the elements of the joints under consideration.

The experiments on diagnosing the state of the elements of conductive rail joints on the main railways using the proposed method have confirmed the accuracy of the determination of the current state of the considered elements, sufficient for practical purposes.

Literature

1. Arkatov B.C., Kravtsov Yu.A., Stepensky B.M. Rail chains. Analysis of work and maintenance. - M .: Transport, 1990 .-- 295 p.

2. Copyright certificate No. 1792861, cl. B61L 23/16. Joint gauge for electrified railway lines / V.I. Shamanov, K.S. Mukhamedzhanov, L.V. Nikulin, V.L. Mikhaldyk, B.M. Vedernikov.

Claims (1)

A method for diagnosing the state of the elements of conductive rail joints, which consists in measuring the voltage drop from the traction and signal current at the conductive joint and on one meter of solid rail, calculating the ratio of these voltages and comparing the result with the allowable value of this ratio determines whether this or not a joint, characterized in that, in order to ensure the process of diagnosing the state of the elements of the conductive junction, currents are mainly measured mainly and the double connecting the rail rail connectors, calculate the relative current values in each connector by dividing the product of the current through the corresponding connector and the electrical resistivity of the rails to this current by the voltage drop on one meter of a solid rail, calculate the relative current value through the rail plates by subtracting from the unit the sum of the currents in the butt connectors, multiplied by the electrical resistivity of the rails and divided by the voltage drop on one meter of a solid rail, and then By introducing the found relative values of the currents in the elements of the joint with their permissible values, they conclude that the elements are malfunctioning, the relative value of the currents in which is less than their permissible values.