WO2020136370A1

WO2020136370A1 - Method and apparatus for leak point detection

Info

Publication number: WO2020136370A1
Application number: PCT/GB2019/053683
Authority: WO
Inventors: Michael John Norrington; Simon Nicholas PETERS; Neil William HARBER; Kevin Frederick OSBORN
Original assignee: Edwards Ltd
Current assignee: Edwards Ltd
Priority date: 2018-12-24
Filing date: 2019-12-23
Publication date: 2020-07-02
Anticipated expiration: 2021-06-24
Also published as: GB2580176A; JP7484044B2; CN113242967A; GB2580176B; JP2022514777A; KR20210105904A; DE112019006386T5; GB201821177D0

Abstract

A method of detecting a leak point (24) on a fluid line (18), the method comprising: while maintaining the fluid line (18) in a state in which the fluid line (18) is substantially filled with air at ambient pressure, emitting ultrasound (25) into the fluid line (18) using an ultrasound emitter (20); and detecting, using an ultrasound detector (22), that the emitted ultrasound (25) is exiting the fluid line (18) at the leak point (24) on the fluid line (18).

Description

METHOD AND APPARATUS FOR LEAK POINT DETECTION

FIELD OF THE INVENTION

The present invention relates to leak point detection in vacuum pumping and/or abatement systems or other types of industrial equipment.

BACKGROUND

Vacuum pumping and/or abatement systems are used in varied and different technological fields, for example in semiconductor fabrication. Typically, in said systems, vacuum pumping equipment is used to pump process gas (e.g. gas from an industrial process) out of a particular place, and abatement equipment is used to abate (e.g. destroy or dispose of) undesirable substances (e.g. exhaust gas) which have been produced.

Vacuum pumping and/or abatement systems comprise fluid lines for conveying various fluids through the system. Typically, it is desirable to detect whether or not there are any leak points in said fluid lines so that the leak points may be repaired.

SUMMARY OF INVENTION In a first aspect of the invention, there is provided a method of detecting a leak point on a fluid line, the method comprising: while maintaining the fluid line in a state in which the fluid line is substantially filled with air at ambient pressure, emitting ultrasound into the fluid line using an ultrasound emitter; and detecting, using an ultrasound detector, that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

The method may further comprise moving the ultrasound detector along the fluid line until the ultrasound detector detects the emitted ultrasound.

The method may further comprise providing, by the ultrasound detector, an indication that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line. The method may further comprise determining a location of the leak point based on the detecting.

The method may further comprise repairing the fluid line to remove the leak point.

The ultrasound emitter may be embedded in the fluid line.

The ultrasound emitter may be either fixedly attached to the fluid line or removably attached to the fluid line.

The ultrasound detector may be a separate unit to the ultrasound emitter and the fluid line.

The state may be a state in which there is no bulk movement of fluid through the fluid line in a particular direction.

The fluid line may comprise two pipe sections connected to each other at a joint. The point at which the emitted ultrasound is exiting the fluid line may be at the joint between the two pipe sections.

The fluid line may be any of the following: a fluid line for conveying cooling water; or a fluid line for conveying nitrogen gas; or a fluid line for conveying clean dry air.

The fluid line may be a fluid line of a vacuum pumping and/or abatement system.

In a second aspect of the invention, there is provided a method of detecting a leak point on a fluid line, the fluid line being configured to convey a particular fluid, the method comprising: while maintaining the fluid line in a state in which the particular fluid is not being conveyed through the fluid line, emitting ultrasound into the fluid line using an ultrasound emitter; and detecting, using an ultrasound detector, that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

In a third aspect of the invention, there is provided a method of detecting a leak point on a fluid line, the method comprising: while maintaining the fluid line in a state in which there is no bulk movement of fluid through the fluid line in a particular direction, emitting ultrasound into the fluid line using an ultrasound emitter; and detecting, using an ultrasound detector, that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

In a fourth aspect of the invention, there is provided a method of detecting a leak point on a fluid line, the method comprising: while maintaining the fluid line in a state in which fluid is not being transported through the fluid line, emitting ultrasound into the fluid line using an ultrasound emitter; and detecting, using an ultrasound detector, that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 is a schematic illustration (not to scale) showing a perspective view of a vacuum pumping and/or abatement system;

Figure 2 is a schematic illustration (not to scale) showing a side view of a leak point detection system for detecting leak points in the vacuum pumping and/or abatement system; and

Figure 3 is a flowchart showing various steps of a method of detecting a leak point using the leak point detection system.

DETAILED DESCRIPTION

Figure 1 is a schematic illustration (not to scale) showing a perspective view of an embodiment of a vacuum pumping and/or abatement system 10.

The vacuum pumping and/or abatement system 10 comprises a frame 12, a vacuum pumping and/or abatement apparatus 14, an input line 16, an output line 18 and an ultrasound emitter 20. It will be appreciated that the vacuum pumping and/or abatement system 10 also comprises other elements (e.g. electrical wiring, sensors, electronic controllers, other lines, other vacuum pumping and/or abatement apparatuses), but these are not shown for the sake of simplicity. The vacuum pumping and/or abatement system 10 is usable to perform vacuum pumping and/or abatement in a facility such as a semiconductor fabrication facility. The vacuum pumping and/or abatement system 10 may be an integrated system. The term“integrated system” may be used to refer to two or more modules integrated together into a common system, the modules being selected from the group of modules consisting of: a module comprising vacuum pumping apparatus, a module comprising abatement apparatus, and a module comprising an electronic controller for controlling the vacuum pumping and/or abatement apparatuses.

The frame 12 defines a space in which the vacuum pumping and/or abatement apparatus 14 is located. The input line 16 extends into the space defined by the frame 12 and is fluidly connected to an inlet of the vacuum pumping and/or abatement apparatus 14. The input line 16 is configured to supply fluid to the vacuum pumping and/or abatement apparatus 14 via the inlet. The output line 18 extends into the space defined by the frame 12 and is fluidly connected to an outlet of the vacuum pumping and/or abatement apparatus 14. The output line 18 is configured to receive fluid from the vacuum pumping and/or abatement apparatus 14 via said outlet. The input and output lines 16, 18 are each formed from one or more sections of pipe. In this embodiment, the input and output lines 16, 18 are cooling water lines, i.e. lines for conveying water through the vacuum pumping and/or abatement apparatus 14 to cool the vacuum pumping and/or abatement apparatus 14.

The ultrasound emitter 20 is attached to the output line 18 and is usable as part of a leak point detection system. This will now be described with reference to Figures 2 and 3.

Figure 2 is a schematic illustration (not to scale) showing a side view of an embodiment of a leak point detection system 100.

The leak point detection system 100 comprises the output line 18, the ultrasound emitter 20 and an ultrasound detector 22. The output line 18 has a leak point 24 from which fluid conveyed through the output line 18 will leak. In this embodiment, the output line 18 comprises two pipe sections connected to each other at a joint, and the leak point 24 is located at the joint between the two pipe sections. The ultrasound emitter 20 is configured to emit ultrasound 25 at an ultrasound frequency, e.g. 40 kHz. The ultrasound emitter 20 is attached to the output line 18 such that it is able to emit ultrasound 25 into the output line 18. In this embodiment, the ultrasound emitter 20 is embedded in the output line 18. More specifically, the output line 18 has an opening (or port) in its wall and the ultrasound emitter 20 is attached to the output line 18 such that it is received in the opening/port (e.g. attached via a flange around the opening/port). The ultrasound emitter 20 may be fixedly attached to the output line 18 or removably attached to the output line 18.

The ultrasound detector 22 is configured to detect the presence of ultrasound 25 within a detection range, e.g. within 5 cm. In particular, the ultrasound detector 22 is configured to detect the ultrasound 25 emitted by the ultrasound emitter 20. The ultrasound detector 22 is also configured to, in response to detecting the presence of ultrasound 25 in its detection range, provide an indication that ultrasound 25 has been detected in its detection range. For example, the ultrasound detector 22 may comprise a display and the indication may be a visual indication on the display. Alternatively, the indication may be an audible indication such as an alarm. In this embodiment, the ultrasound detector 22 is not attached to the output line 18 or the ultrasound emitter 20, and represents a separate unit to the output line 18 and the ultrasound emitter 20.

The ultrasound emitter 20 and ultrasound detector 22 are usable to detect the leak point 24 in the output line 18. This will now be described with reference to Figure 3.

Figure 3 is a flowchart showing various steps of a method of detecting a leak using the leak point detection system 100 illustrated in Figure 2.

It will be appreciated that some of the process steps depicted in the flowchart of Figure 3 and described below may be omitted or performed in differing order to that presented below and shown in Figure 3. Furthermore, although the process steps have, for convenience and ease of understanding, been depicted as discrete temporally-sequential steps, nevertheless some of the process steps may in fact be performed simultaneously or at least overlapping to some extent temporally. At step s2, a user maintains the output line 18 in a state in which it is substantially filled with air at ambient pressure, i.e. air at the same pressure as the environment in which the output line 18 is located. For example, the air may be at atmospheric pressure if the output line 18 is located in an environment at atmospheric pressure. In this state, the output line 18 is not being used to transport fluid, i.e. there is no bulk movement of fluid through the output line 18 in a particular direction. Thus, in this state, the output line 18 is not conveying the fluid that it is configured to convey.

At step s4, while maintaining the output line 18 in the state described above for step s2, the user operates the ultrasound emitter 20 to emit ultrasound 25 into the output line 18. The emitted ultrasound 25 travels throughout the inside of the output line 18 via the air in the output line 18. In this way, the emitted ultrasound 25 travels from the ultrasound emitter 20 to the leak point 24, and exits the output line 18 at the leak point 24. Thus, operation of the ultrasound emitter 20 to emit ultrasound 25 into the output line 18 causes ultrasound 25 to exit the output line 18 at the leak point 24.

At step s6, the user moves the ultrasound detector 22 along the output line 18 until the ultrasound detector 22 detects the presence of the emitted ultrasound in its detection range. More specifically, the ultrasound detector 22 is continuously moved by the user along the exterior of the output line 18 adjacent to the output line 18. When the ultrasound detector 22 reaches a location where the leak point 24 is in the detection range of the ultrasound detector 22, the ultrasound detector 22 detects the emitted ultrasound exiting the output line 18 at the leak point 24.

At step s8, in response to the detection of the presence of the emitted ultrasound 25 in the detection range of the ultrasonic detector 22, the ultrasound detector 22 provides an indication that the emitted ultrasound 25 has been detected in its detection range. For example, the indication may be a visual indication displayed on a display of the ultrasound detector 22. Alternatively, the indication may be an audible indication such as an alarm.

At step s10, the user determines, based on the indication, that there is a leak point 24 on the output line 18. In addition, the user determines that the location of the leak point 24 is a location on the output line 18 adjacent to the ultrasound detector 22 at the point in time that the indication is provided by the ultrasound detector 22. Following this, the user may repair the output line 18 to remove the leak point 24.

Thus, a system and method for detecting leaks in a vacuum pumping and/or abatement system is provided.

Advantageously, the above described system and method tend to allow leaks in a fluid line to be detected without transporting fluid through the fluid line. This tends to mean that a leak point can be detected without any actual leakage of transported fluid occurring, which tends to be particularly useful if the fluid to be transported through the fluid line is a hazardous substance (e.g. corrosive or toxic) or is at high pressure/temperature. For example, leakage of nitrogen gas tends to cause oxygen depletion in the immediate environment around the fluid line, which tends to be hazardous for users. Avoiding leakage of nitrogen gas tends to avoid this hazard.

Moreover, the ability to detect leaks without transporting fluid through the fluid line tends to allow leak checks to be performed relatively easily and quickly, which in turn tends reduce the amount of time involved in setting up a vacuum pumping and/or abatement system for use.

Advantageously, the above described system and method tend to be particularly useful when used to detect leaks in large systems with many joints between pipe sections (such as an integrated vacuum pumping and/or abatement system), since leaks tend to occur more frequently at joints between pipe sections.

In the above embodiments, the leak point detection system is used to detect leaks in a cooling water output line. Flowever, in other embodiments, the leak point detection system is used with another type of fluid line, e.g. a process gas input line, a process gas output line, a fluid line for conveying clean dry air, a fluid line for conveying nitrogen purge gas.

In the above embodiments, the leak point detection system is used to detect leaks in a line which is fluidly connected to a vacuum pumping and/or abatement apparatus. Flowever, in other embodiments, the leak point detection system is used to detect leaks in a fluid line which is not fluidly connected to a vacuum pumping and/or abatement apparatus.

In the above embodiments, the leak point is located at a joint between two sections of pipe. However, in other embodiments, the leak point is located at different location on the fluid line, i.e. not at a joint between two sections of pipe. In general, it will be appreciated that the leak point may be at any location on the fluid line.

In the above embodiments, the ultrasound detector is continuously moved along the fluid line to detect the leak point. However, in other embodiments, the ultrasound detector is not continuously moved along the fluid line and is instead sequentially placed at various different locations on the fluid line to detect whether or not there is a leak point at each of those locations.

In the above embodiments, the leak detection system is used to detect leaks in a fluid line of a vacuum pumping and/or abatement system. However, it will be appreciated that the leak detection system may be used with fluid lines of other types of industrial system.

REFERENCE NUMERAL KEY

10: vacuum pumping and/or abatement system

12: frame

14: vacuum pumping and/or abatement apparatus 16: input line

18: output line

20: ultrasound emitter

22: ultrasound detector

24: leak point

25: ultrasound

100: leak point detection system

Claims

1. A method of detecting a leak point on a fluid line, the method comprising: while maintaining the fluid line in a state in which the fluid line is substantially filled with air at ambient pressure, emitting ultrasound into the fluid line using an ultrasound emitter; and

detecting, using an ultrasound detector, that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

2. The method of claim 1 , further comprising:

moving the ultrasound detector along the fluid line until the ultrasound detector detects the emitted ultrasound.

3. The method of claim 1 or claim 2, further comprising:

providing, by the ultrasound detector, an indication that the emitted ultrasound is exiting the fluid line at the leak point on the fluid line.

4. The method of any of claims 1 to 3, further comprising:

determining a location of the leak point based on the detecting.

5. The method of any of claims 1 to 4, further comprising:

repairing the fluid line to remove the leak point.

6. The method of any of claims 1 to 5, wherein the ultrasound emitter is embedded in the fluid line.

7. The method of claim any of claims 1 to 6, wherein the ultrasound emitter is either fixedly attached to the fluid line or removably attached to the fluid line.

8. The method of any of claims 1 to 7, wherein the ultrasound detector is a separate unit to the ultrasound emitter and the fluid line.

9. The method of any of claims 1 to 8, wherein the state is a state in which there is no bulk movement of fluid through the fluid line in a particular direction.

10. The method of any of claims 1 to 9, wherein the fluid line comprises two pipe sections connected to each other at a joint, and the point at which the emitted ultrasound is exiting the fluid line is at the joint between the two pipe sections.

11. The method of any of claims 1 to 10, wherein the fluid line is any of the following:

a fluid line for conveying cooling water; or

a fluid line for conveying nitrogen gas; or

a fluid line for conveying clean dry air.

12. The method of any of claims 1 to 1 1 , wherein the fluid line is a fluid line of a vacuum pumping and/or abatement system.

13. A method of detecting a leak point on a fluid line, the fluid line being configured to convey a particular fluid, the method comprising:

while maintaining the fluid line in a state in which the particular fluid is not being conveyed through the fluid line, emitting ultrasound into the fluid line using an ultrasound emitter; and

14. A method of detecting a leak point on a fluid line, the method comprising: while maintaining the fluid line in a state in which there is no bulk movement of fluid through the fluid line in a particular direction, emitting ultrasound into the fluid line using an ultrasound emitter; and

15. A method of detecting a leak point on a fluid line, the method comprising:

while maintaining the fluid line in a state in which fluid is not being transported through the fluid line, emitting ultrasound into the fluid line using an ultrasound emitter; and