METHOD FOR MEASURING THE SIZE OF A LEAK FLOW OF A SEAL

Abstract

The disclosure relates to a method for measuring the size of a leakage flow of a seal. In exemplifications of the disclosure, a leakage sensor is provided on a leakage side of the seal, said leakage sensor comprising at least one heating element and at least two temperature sensors which are in heat-transferring connection with the leakage flow. In exemplifications, the following steps are utilized: continuous or intermittent detection of a temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by means of the temperature sensors, wherein a predetermined constant reference heat quantity is simultaneously generated by the heating element and transferred into the leakage flow in the section of the leakage channel, and determination of the size of the current leakage flow as a function of the currently detected temperature difference; or continuously or intermittently setting a constant temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by generating a variable amount of heat with the heating element and transferring the amount of heat into the leakage flow in the section of the leakage channel, and determining the size of the current leakage flow as a function of the currently generated amount of heat.

Claims

1. Method for measuring the size of a leakage flow of a seal, wherein a leakage sensor is provided on a leakage side of the seal, said leakage sensor comprising at least one heating element and at least two temperature sensors which are in heat-transferring connection with the leakage flow, comprising the following steps: continuous or intermittent detection of a temperature difference by means of the temperature sensors in the leakage flow over a section of a leakage channel through which the leakage flow flows, wherein a predetermined constant reference heat quantity is simultaneously generated with the heating element and transmitted into the leakage flow in the section of the leakage channel, and determination of the size of the current leakage flow as a function of the currently detected temperature difference; or continuously or intermittently setting a constant temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by generating a variable amount of heat with the heating element and transferring the amount of heat into the leakage flow in the section of the leakage channel, and determining the size of the current leakage flow as a function of the currently generated amount of heat; characterized in that, when determining the size of the current leakage flow, in addition to the currently detected temperature difference when a constant reference heat quantity is generated or in addition to the currently generated heat quantity when a constant temperature difference is set, the current absolute temperature of the leakage flow in the section through which the heat flows upstream of the heating element is detected and taken into account.

2. Method for measuring the size of a leakage flow of a seal, wherein a leakage sensor is provided on a leakage side of the seal, said leakage sensor comprising at least one heating element and at least two temperature sensors which are in heat-transferring connection with the leakage flow, comprising the following steps: continuous or intermittent detection of a temperature difference by means of the temperature sensors in the leakage flow over a section of a leakage channel through which the leakage flow flows, wherein a predetermined constant reference heat quantity is simultaneously generated by the heating element and transferred into the leakage flow in the section of the leakage channel, and determination of the size of the current leakage flow as a function of the currently detected temperature difference; or continuously or intermittently setting a constant temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by generating a variable amount of heat with the heating element and transferring the amount of heat into the leakage flow in the section of the leakage channel, and determining the size of the current leakage flow as a function of the currently generated amount of heat; characterized in that, when determining the size of the current leakage flow, in addition to the currently detected temperature difference when generating a constant reference heat quantity or in addition to the currently generated heat quantity when setting a constant temperature difference, an aggregate state and/or a composition of a medium forming the leakage flow is taken into account.

3. Method according to claim 1, characterized in that, in order to calibrate the measurement, a predetermined temperature difference is set at first in the leakage flow over the flowed-through section by heating the leakage flow in the flowed-through section with the heating element, the wherein heat quantity produced by the heating element when the predetermined temperature difference is reached is determined as the reference heat quantity.

4. Method according to claim 1, characterized in that the calibration of the measurement is carried out for different absolute temperatures of the leakage flow in the flowed-through section in front of the heating element, and different reference heat quantities are determined and assigned to the respective absolute temperature, and in that this temperature assignment is taken into account when determining the size of the current leakage flow.

5. Method according to claim 2, characterized in that the calibration of the measurement is carried out for different aggregate states and/or different compositions of the medium, and different reference heat quantities are determined and assigned to the respective aggregate state and/or the respective composition of the medium, and in that this medium assignment is taken into account when determining the size of the current leakage flow.

6. Method according to claim 3, characterized in that, for calibration of the measurement, the at least one reference heat quantity is also generated with the heating element and, by targeted variation of the size of the leakage flow, the temperature differences which are respectively produced in the process are detected and assigned to the respective leakage flow size, and in that this temperature difference assignment is taken into account when determining the size of the current leakage flow.

7. Method according to claim 4, characterized in that the temperature difference assignment is carried out by means of a leakage flow size-temperature difference curve and the temperature assignment is carried out by means of an assignment of a leakage flow size-temperature difference curve to the respective absolute temperature.

8. Method according to claim 5, characterized in that the temperature difference assignment is carried out by means of a leakage flow size-temperature difference curve and the medium assignment is carried out by means of an assignment of a leakage flow size-temperature difference curve to the respective aggregate state and/or the respective composition of the medium.

9. Method according to claim 5, characterized in that, for calibration of the measurement, furthermore the constant temperature difference in the leakage flow is generated with the heating element over the section of the leakage channel through which the leakage flow flows, and by targeted variation of the size of the leakage flow, the heat quantity required for this in each case to be generated with the heating element is detected and assigned to the respective leakage flow size, and in that this heat quantity assignment is taken into account when determining the size of the current leakage flow.

10. Method according to claim 4, characterized in that the heat quantity assignment is carried out by means of a leakage flow size-heat quantity curve and the temperature assignment is carried out by means of an assignment of a leakage flow size-heat quantity curve to the respective absolute temperature.

11. Method according to claim 5, characterized in that the heat quantity assignment is carried out by means of a leakage flow size-heat quantity curve and the medium assignment is carried out by means of an assignment of a leakage flow size-heat quantity curve to the respective aggregate state and/or the respective composition of the medium.

12. Method according to claim 1, characterized in that a limit leakage flow size is specified and the currently determined size of the leakage flow is compared with the limit leakage flow size and a warning message and/or a warning signal is output as a function of this comparison, wherein the limit leakage flow size is specified as a function of a diameter of the seal, wherein in particular different limit leakage flow sizes are assigned to different diameters of the seal.

13. Method according to claim 12, characterized in that the predetermined limit leakage flow size is predetermined as a function of at least one further parameter which is variably adjustable, wherein the at least one parameter describes at least one of the following quantities and/or specifications: type of medium whose medium flow is sealed with the seal, especially oil or water; operating temperature of a medium flow sealed by the seal; operating temperature range of a medium flow sealed by the seal.

14. Method according to claim 1, characterized in that, when determining the size of the current leakage flow, the aggregate state and/or the composition of a medium forming the leakage flow is additionally taken into account.

15. Method according to claim 1, characterized in that the size of a leakage flow of a mechanical seal in a rotary union is measured.

16. Method according to claim 2, characterized in that, in order to calibrate the measurement, a predetermined temperature difference is set at first in the leakage flow over the flowed-through section by heating the leakage flow in the flowed-through section with the heating element, the wherein heat quantity produced by the heating element when the predetermined temperature difference is reached is determined as the reference heat quantity.

17. Method according to claim 3, characterized in that the calibration of the measurement is carried out for different absolute temperatures of the leakage flow in the flowed-through section in front of the heating element, and different reference heat quantities are determined and assigned to the respective absolute temperature, and in that this temperature assignment is taken into account when determining the size of the current leakage flow.

18. Method according to claim 3, characterized in that the calibration of the measurement is carried out for different aggregate states and/or different compositions of the medium, and different reference heat quantities are determined and assigned to the respective aggregate state and/or the respective composition of the medium, and in that this medium assignment is taken into account when determining the size of the current leakage flow.

19. Method according to claim 4, characterized in that, for calibration of the measurement, the at least one reference heat quantity is also generated with the heating element and, by targeted variation of the size of the leakage flow, the temperature differences which are respectively produced in the process are detected and assigned to the respective leakage flow size, and in that this temperature difference assignment is taken into account when determining the size of the current leakage flow.

20. Method according to claim 5, characterized in that, for calibration of the measurement, the at least one reference heat quantity is also generated with the heating element and, by targeted variation of the size of the leakage flow, the temperature differences which are respectively produced in the process are detected and assigned to the respective leakage flow size, and in that this temperature difference assignment is taken into account when determining the size of the current leakage flow.

Description

DETAILED DESCRIPTION

[0038] The disclosure shall be described by way of example in the following by means of an embodiment example and the FIGURES.

[0039] FIG. 1 schematically shows a rotary union with a mechanical seal 1, which seals a medium-carrying channel 2 from the environment. Only as an example, the channel 2 extends from a stationary component 3 into a component 5 rotating around an axis of rotation 4. However, this is only exemplary and the disclosure can be applied to any seal, especially to pump or compressor seals.

[0040] A leakage chamber 6 is provided on a side facing away from channel 2. This leakage chamber 6 receives medium from channel 2 via the mechanical seal 1. Leakage chamber 6 is connected to a leakage channel 7, which has a section 8 through which the leakage flow passes. In particular, the leakage channel 7 extends outside the leakage chamber 6, e.g. outside a housing 9 accommodating the mechanical seal 1, which encloses or forms the stationary component 3, for example.

[0041] A leakage sensor 10 is provided in or at section 8 of the leakage channel 7, comprising a first temperature sensor 11 and a second temperature sensor 12 and a heating element 13. The first temperature sensor 11 is positioned at an upstream end of section 8, the second temperature sensor 12 at a downstream end. In the direction of flow of the leakage flow between the first temperature sensor 11 and the second temperature sensor 12, the heating element 13 is positioned, here close or comparatively closer to the second temperature sensor 12.

[0042] In addition, a control device 14 may be provided which controls, for example, the temperature sensors 11, 12 and the heating element 13 and is arranged to carry out a method according to the disclosure. The control device 14 and the sensors 11, 12 may be positioned together with the heating element 13, in particular in a common housing 15.

[0043] According to the disclosure, the leakage sensor 10 not only detects a temperature difference of the leakage flow by means of the first temperature sensor 11 and the second temperature sensor 12, wherein the leakage medium is heated simultaneously with the heating element 13, but, for example, the first temperature sensor 11 is also used to detect the absolute temperature of the leakage flow in the flow direction upstream of the heating element 13. As explained, the aggregate state of the leakage flow and/or a composition of the same can also be used additionally or alternatively in determining the current leakage flow, for example by entering the aggregate state and/or the composition of the leakage medium into the control device 14, manually or automatically by means of a corresponding sensor which is not shown in more detail here.

LIST OF REFERENCE NUMERALS

[0044] 1 Mechanical seal [0045] 2 Channel [0046] 3 Stationary component [0047] 4 Axis of rotation [0048] 5 Rotating component [0049] 6 Leakage chamber [0050] 7 Leakage channel [0051] 8 Section [0052] 9 Housing [0053] 10 Leakage sensor [0054] 11 First temperature sensor [0055] 12 Second temperature sensor [0056] 13 Heating element [0057] 14 Control device [0058] 15 Housing