GB2553585A

GB2553585A - Wear detection

Info

Publication number: GB2553585A
Application number: GB1615521.0A
Authority: GB
Inventors: Wasa Tverlid Steinar
Original assignee: Statoil ASA
Current assignee: Equinor ASA
Priority date: 2016-09-13
Filing date: 2016-09-13
Publication date: 2018-03-14
Also published as: GB201615521D0

Abstract

A component 20 for use in a fluid system is worn by passage of fluid (erosion) during normal operation of the system. The system may be a valve or pipe. The component comprises a wearable portion 30 having a fluid contact surface to be exposed to the fluid during normal operation (leading edge 28), and a wear indication element (wire 32) located within the wearable portion and configured to wear together with the fluid contact surface, wherein a property of the wear indication element is detectable to indicate wear of the fluid contact surface. The element 32 may be a conductive loop and electrical resistance of the element 32 is monitored and changes when the element wears or breaks. Alternatively the element may comprise a capacitor having electrodes which erode and capacitance changes are measured to indicate a degree of wear.

Description

(71) Applicant(s):

Statoil ASA (Incorporated in Norway)

Forusbeen 50, 4035 Stavanger, Norway (72) Inventor(s):

Steinar Wasa Tverlid (51) INT CL:

G01N 3/56 (2006.01) G01N 27/20 (2006.01)

G01N 17/00 (2006.01) G01N 27/24 (2006.01)

(56) Documents Cited: EP 0060069 A1	EP 0058653 A1
WO 2011/137539 A1	WO 2005/036043 A1
WO 2000/061472 A1	DE 019620954 A1
JP 2004077252 A	US 6208128 B1
(58) Field of Search: INT CL G01N Other: WPI, EPODOC

(74) Agent and/or Address for Service:

Dehns

St. Bride's House, 10 Salisbury Square, LONDON, EC4Y 8JD, United Kingdom (54) Title of the Invention: Wear detection

Abstract Title: Wear detection of a component in a fluid system (57) A component 20 for use in a fluid system is worn by passage of fluid (erosion) during normal operation of the system. The system may be a valve or pipe. The component comprises a wearable portion 30 having a fluid contact surface to be exposed to the fluid during normal operation (leading edge 28), and a wear indication element (wire 32) located within the wearable portion and configured to wear together with the fluid contact surface, wherein a property of the wear indication element is detectable to indicate wear of the fluid contact surface. The element 32 may be a conductive loop and electrical resistance of the element 32 is monitored and changes when the element wears or breaks. Alternatively the element may comprise a capacitor having electrodes which erode and capacitance changes are measured to indicate a degree of wear.

FIG. 4 /5 /

FIG. 1 (Prior Art)

FIG. 2 (Prior Art)

2/5

FIG. 3

FIG. 4

3/5

FIG. 5

FIG. 6

4/5

FIG. 7

-j

FIG. 8

5/5

FIG. 9

Tk i ί V

-If ) § ΐ $ ί

- 1 .

WEAR DETECTION

The present invention relates to detection of component wear in a fluid system, such as in valves and the like.

Figures 1 and 2 illustrate an exemplary valve 2. The valve 2 comprises a housing 4 having a fluid inlet 6 and a fluid outlet 8. Within the housing 2 is provided a valving arrangement. The illustrated valve 2 is a choke valve 2 having a fixed, radially-ported internal nozzle 10 with an external sliding sleeve 12. To open the valve, the sliding sleeve 12 is moved upwards to expose ports 11 in the internal nozzle 10,

The external sleeve 12 to provides superior wear control over other choke valve configurations by controlling the high velocity flow jets during throttling by directing the flow upwards into the sleeve 12.. thereby containing the erosive energy. The potential wear is then contained to the replaceable nozzle 10 and sliding sleeve 12.

These components, however, are hidden during use and inspection of these components requires disassembly of the valve 2. Accordingly, the Inventors have identified that a need exists to determine when these components require replacement without disassembling the valve 2 to perform an inspection.

The present invention provides a component for use in a fluid system, wherein the component is worn by passage of a fluid during normal operation of the fluid system, the component comprising: a wearable portion having a fluid-contact surface to be exposed to the fluid during normal operation; and a wear-indication element located within the wearable portion and configured to wear together with the fluid-contact surface, wherein a property of the wear-indication element is detectable to indicate wear of the fluid-contact surface.

The present configuration thus provides a means for detecting wear of the component without the need to disassemble the component.

Preferably the detectable property of the wear-indication element is electrically detectable, and/or is preferably an electrical property of the wearindication element or a part thereof. Preferably the component comprises external connections to permit detection of the detectable property, such as electrical terminals.

In one embodiment, the wear-indication element may comprise a conductive loop positioned so as to be broken or exposed by a predetermined level of wear of

- 2 the fluid-contacting surface. For example, the predetermined level of wear may correspond to a level of wear requiring replacement of the component or a part of the component, such as the wearable portion.

This configuration provides a simple means for detecting wear at the 5 location of the loop by monitoring for a change in the eiectrica! resistance of the loop.

in most cases, the breaking of the loop would be expected to cause a significant increase in resistance. However, if a conductive fluid is present, then the resistance change may be less marked.

In some cases, exposure of the conductive loop to the fluid may be detectable as a change in resistance. For example, the conductive loop may comprise a resistive or insulating portion (or even a break) configured such that exposure of the conductive loop by wear of the fluid-contact surface causes the resistive or insulating portion to be short-circuited. Thus, a conductive fluid may cause a detectable decrease in the resistance of the conductive ioop.

Optionally, the wear-indication element may comprise only a single conductive ioop. By making assumptions of how the component wears, for example if the flow conditions and component configuration are known, then it may be possible to make an assessment of the overall wear of the wearable piece of the component based on a single measurement.

The wear-indication element may in some embodiments comprise a pluraiity of elements, such as the conductive loops described above. The use of multiple elements may allow more precise measurement of the wear of the wearable portion.

For example, each conductive loop may be positioned so as io be broken by a respective predetermined level of wear of the fluid-contacting surface. Preferably, the plurality of conductive loops may be arranged such that current flow along each conductive ioop can be independently measured, or it can be otherwise determined which conductive loops have been broken by wear. Thus, the wear indicator provides an incremental measurement of the degree of wear of the fluid-contact surface.

in another example, the elements (e.g. conductive loops) may be positioned different locations along the fluid-contacting surface. Thus, a determination of wear may be made at multiple locations. This is particularly useful where the wear of the component is less predictable.

-3in one embodiment, the plurality of elements (e.g, conductive loops) may be arranged in series. Thus, only a single output needs to be monitored to determine whether any of the loop locations have reached the wear limit.

In one embodiment, the wear-indication element may comprise a capacitor 5 arranged such that wear of the fluid-contacting surface causes a change in the capacitance of the capacitor. For example, the capacitor may comprise two plates separated by a dielectric material, the capacitor being oriented such that wear of the fluid-contacting surface causes a decrease to the surface area of at least one, preferably both, plates. Thus, the wear of the plates causes the capacitance to vary with wear.

Use of a capacitor in this manner, similar to using multiple proximate loops, may allow for the level of wear of the fluid-contact surface to be measured directly, as opposed to merely monitoring for an indication that a threshold ievei of wear has been required. Such a configuration may ailow for planning of repairs in advanced.

Furthermore, several components may be replaced at the same time, even though some may not have reached the threshold wear that would normally necessitate replacement, so to minimise down-times.

The component may be one in which the fluid-contacting surface is not visible during normal operation of the component. More particularly, the fluid20 contacting surface may not be accessible without disconnection of the component from the fluid system. Such components benefit particularly from the described configuration because it would be otherwise difficult to monitor the degree of wear of the component.

Preferably the component Is a valve or a part of a valve, such as a sealing element. For example, the fluid-contact surface may comprise a surface of a sealing element of the valve. Such components are often hidden during use, but are the most common component of the vaive to fail due to wear.

In alternative configurations, the component may comprise other components In the fluid system. For example, the component may comprise a fluid pipe. The wear-indication element may, for example, be located adjacent a bend in the fluid pipe. Such locations often suffer increased wear. Further examples include fluid tanks, such as separators or fluid containers.

The present invention may further provide a testing apparatus for connection to a component as described above, wherein the testing apparatus is configured to apply a charge to the wear-detection element so as to monitor a

-4~ property of the wear-detection element and provide an output indicative of a degree of wear of the wear-detection element and/or the wearable portion of the component.

Viewed from a second aspect, the present invention also provides a method 5 of detecting wear of fluid-contacting surface of a wearable portion of a component in a fluid system, the method comprising: monitoring a property of a wear-indication element disposed within the wearable portion that wears together with the fluidcontacting surface.

Preferably the monitoring comprises electrically monitoring the property, and 10 the property is preferably an electrical property of the wear-indication element.

Preferably the monitoring does not require disassembly of the component.

The wear-indication element may comprise a conductive loop positioned so as to be broken or exposed by a predetermined level of wear of the fluid-contacting surface. The monitoring may then comprise detecting a change in resistance of the conductive loop, wherein the change may be an increase in resistance, such as corresponding to a break in the conductive loop, or a decrease in resistance, such as corresponding to a short-circuit by a conductive fluid of an insulating or resistive portion of the conductive loop.

The wear-indication element may comprise a plurality of conductive loops.

In one embodiment, each conductive loop may be positioned so as to be broken or exposed by a respective predetermined level of wear of the fluid contacting surface. The plurality of conductive loops are thus preferably located proximate one another. The method may comprise independently monitoring the resistance of each of the plurality of conductive loops. The method may further comprise determining that a degree of wear is within a range of values based on the measured properties of the plurality of loops.

Sn one embodiment, the conductive loops may be positioned different locations along the fluid-contacting surface. The plurality of conductive loops may be arranged in series. The monitoring may comprise monitoring a single output to determine whether any of the loop locations have reached their wear limit.

In an alternative embodiment, the wear-indication element may comprise a capacitor arranged such that wear of the fluid-contacting surface causes a change in the capacitance of the capacitor. The monitoring may comprise measuring a capacitance of the capacitor. The method may comprise determining a degree of wear of the wearable component based on the measured capacitance.

, 5 The fluid-contacting surface is preferably not visible during normal operation of the component. In some embodiments, the fluid-contacting surface may not be accessible without disconnection of the component from the fluid system.

Preferably the component is a valve or a part of a valve, such as a sealing 5 element or the like. For example, the fluid-contact surface may comprise a surface of a sealing element of the valve.

In alternative configurations, the component may comprise other components in the fluid system. For example, the component may comprise a fluid pipe. The wear-indication element may, for example, be located adjacent a bend In the fluid pipe.

The method may optionally comprise replacing the component or a part of the component, such as the wearable portion, responsive to determining that the fluid-contacting surface has reached a threshold level of wear. The level of wear of the fluid-contacting surface is preferably determined based on the monitoring, for example, when the (or one or more of the) conductive loops is broken or exposed, or when a threshold capacitance of the capacitor is reached.

Certain preferred embodiments of the present invention will now be described In greater detail by way of example only and with reference to the accompanying drawings, in which:

Figure 1 is a vertical cross-section through a prior art choke valve;

Figure 2 is a plan cross-section through the prior art choke valve along section lines A-A;

Figure 3 is a plan cross-section through a first embodiment of a valve including a wear sensor;

Figure 4 is a perspective view showing the internal components of the first embodiment of the valve;

Figure 5 is a plan cross-section through the first embodiment of the valve illustrating wear of a wearable portion of the valve;

Figure 6 is a perspective view showing the internal components of the worn 30 wearable portion of the first embodiment of a valve;

Figure 7 is a perspective view showing the internal components of a second embodiment of a valve including a wear sensor;

Figure 8 is a perspective view snowing the internal components of a third embodiment of a valve including a wear sensor; and

-6Figure 9 is a perspective view showing the internal components of a first embodiment of a pipe section inciuding a wear sensor.

The purpose of the following embodiment is to predict wear in equipment exposed to erosive wear, like choke valves, valves in general, pipe bodies in for example a bend, pressurized or non-pressurized tanks, measuring equipment for flowing media, etc., to allow for part ordering and replacement within a planned maintenance intervai before failure of the equipment. At the same time, the proposed system seeks to extend the effective life time of such parts by more confidently predicting when the component is approaching failure. Measuring wear will allow the performance of maintenance at the correct time, i.e. neither too soon, nor too late.

The principle of the first embodiment is to lead a small thin eiectric wire from a control board into the body of a wearing part and position it just in front of the limit to which the component may allowably wear before replacement is necessary.

When the erosive wear reaches the wire (which is near to the wear limit) the wire will wear off like its surroundings and break the circuit. When the wire is broken, it will no longer conduct electric power. This event is registered outside the equipment on the control board, and the user will get a positive indication of how far the erosive wear has reached.

With reference to Figures 3 to 6, an exemplary valve component 20 is shown, which comprises a plurality of ports 22 connecting an iniet 24 of the valve to an outlet 26 of the vaive. The Illustrated valve component 20 provides a similar function to the radially-ported internal nozzle 10 of the prior art vaive 2.

The valve component 20 has a leading edge 28, which is exposed during normal operation of the valve to a fluid flow 25. The fluid flow 25 causes wear of the leading edge 28, as well as to other areas of the valve component 20, such as around the ports 22. This wear is illustrated in Figures 5 and 6.

In order to detect the degree of wear of the valve component 20, a wear sensor 30 is provided. The wear sensor 30 comprises a thin, electrically-conductive wire loop 32 positioned within the leading edge of the valve component 20. The loop 32 is connected electrically to terminal ends 34, which are exposed from the valve to allow external monitoring of the electrical resistance of the ioop 32. These in turn connect back to a testing device or control circuit (not shown).

When the vaive component 20 wear reaches a predetermined level, the loop

32 becomes exposed to the fluid. In some embodiment, the exposure of the loop

-732 may be detectable as a change in the conductivity of the coii 32. As the component 20 wears further, the ioop 32 is worn together with the leading edge 28 of the component 20 such that the loop 32 is broken. This interrupts the electrical connection between the terminals 34, which can be detected.

The material of the wire coll 32 Is not expected to have any particular properties, other than the reliable conduction of electric power. However, the material of the wire coil 32 should be selected so as not to predominantly break as a result of vibrations, thermal or mechanical fatigue or corrosion - most metals will meet these requirements.

The material of the component 20 surrounding the wire coil 32 is expected to be of sufficiently high quality that the coil 32 will wear out quite quickly when exposed, and then indicate wear. Wear component 20, for example, might typically be made of steel, such as high quality steel CS, 22Cr Duplex, 316, or the like, and may have a STELLITE© 6 hardfacing, for example Particularly high wearing components 20 can be made of massive Tungsten Carbide.

The depth of the loop 32 within the component 20 is selected such that the loop 32 will be broken at the point when the component 20 requires or will shortly require replacement. This is based on the assumption that there is a relationship between the degree of wear at the leading edge and the degree of wear at other locations of the component 20.

Figure 7 illustrates the valve component 20 Including an alternative configuration for the wear sensor 40. The valve component 20 is otherwise unchanged.

In this embodiment, the wear sensor 40 comprises a plurality of conductive loops 42a-e. Each loop 42a-e is positioned at a different depth from the un-worn position of the leading edge 28 of the component 20. Each loop 42a-e shares a common supply line 44, but has an independent return line 46a-e. That is to say, the loops 42a-e are arranged in parallel. Thus, the interruption of each loop can be independently detected, such that the wear sensor 40 can provide a “digital output indicating more precisely the degree of wear of the component 20,

Figure 8 illustrates the valve component 20 including a further alternative configuration for the wear sensor 50. The valve component 20 is again otherwise unchanged.

In this embodiment, the wear sensor 50 comprises a capacitor arrangement

52 having a positive plate 54 and a negative plate 56 separated by a dielectric. As

- 8 the leading edge 28 of the component 20 wears, the plates 54, 56 of the capacitor 52 are worn away such that their area is reduced. The degree of wear can be measured as the measurable capacitance of the capacitor 52 will change proportionally to the remaining size of the device.

The capacitance of the capacitor 52 thus proves an “analog output corresponding to the degree of wear of the component. The operator will then know how much of the part Is left without opening the tooling.

In each of the cases discussed above, it Is important that the wearmeasuring device 30, 40, 50 is placed In a location where the measured wear at this exact spot is representative of the wear of a larger part of the equipment. In this way a larger area can indirectly be monitored.

Whilst the above embodiments relate to a valve component 20, it will be appreciated that wear sensors such as those described above may be employed in a variety of different situations. For example, Figure 9 illustrates a section of pipe

60 incorporating a wear sensor 70 similar to that described in connection with

Figures 3 to 6. As will be seen, the wear sensor 70 is oriented within the wall of the pipe section 60 so as to detect wear of the inner surface 62 of the pipe section 60.

The described wear sensors may similarly be implemented In any component equipment exposed to erosive wear by a fluid system. As discussed above, examples include choke valves, valves in general, pipe bodies, for example in a pipe bend, pressurized or non-pressurized tanks, and measuring equipment for flowing media.

Claims

CLAiMS:

1. A component for use in a fluid system, wherein the component is worn by passage of a fluid during normal operation of the fluid system, the component

5 comprising:

a wearable portion having a fluid-contact surface to be exposed to the fluid during normal operation; and a wear-indication element located within the wearable portion and configured to wear together with the fluid-contact surface, wherein a property of the

10 wear-indication element is detectable to indicate wear of the fluid-contact surface.

2. A component according to claim 1, wherein the detectable property Is an electrical property of the wear-indication element or a part thereof.

15

3. A component according to claim 1 or 2, wherein the wear-indication element comprises at least one conductive loop positioned so as to be broken or exposed by a predetermined level of wear of the fluid-contacting surface.

4. A component according to claim 3, wherein the wear indication element

20 comprises a plurality of conductive loops arranged proximate one another and electrically in parallel, wherein each of the conductive loops indicates a different predetermined level of wear of the fluid-contacting surface.

5. A component according to claim 3, wherein the wear-indication element

25 comprises a plurality of conductive loops positioned at different locations across the fluid-contacting surface.

6. A component according to claim 5, wherein the plurality of conductive loops are arranged electrically in series.

7. A component according to claim 1 or 2, wherein the wear-indication element comprises a capacitor arranged such that wear of the fluid-contacting surface causes a change in the capacitance of the capacitor.

-108. A component according to any preceding claim, wherein the fluid-contacting surface is not visible during normal operation of the component.

9. A component according to any preceding claim, wherein the component is a 5 valve or a part of a valve, such as a sealing element.

10. A testing apparatus for connection to a component according io any preceding claim, wherein the testing apparatus is configured to apply an electrical charge to the wear-detection element so as to monitor a property of the wear10 detection element and provide an output indicative of a degree of wear of the weardetection element and/or the wearable portion of the component,

11. A method of detecting wear of a fluid-contacting surface of a wearable portion of a component in a fluid system, the method comprising:

15 monitoring a property of a wear-indication element disposed within the wearable portion that wears together with the fluid-contacting surface.

12. A method according to claim 11, wherein the property is an electrical property, and wherein the monitoring comprises electrically monitoring the property.

13. A method according to claim 11 or 12, wherein the monitoring does not require disassembly of the component.

14. A method of maintaining a fluid system, comprising:

25 detecting wear of a fluid-contacting surface of a wearable portion of a component in the fluid system by a method according to any of claims 11 to 13; and replacing the component or a part of the component responsive to determining that the fluid-contacting surface has reached a threshold level of wear.

Intellectual

Property

Office

Application No: GB1615521.0 Examiner: Simon Colcombe