WO2017139835A1

WO2017139835A1 - Wear liner and a method for combatting wear

Info

Publication number: WO2017139835A1
Application number: PCT/AU2017/050121
Authority: WO
Inventors: Brady Haneman
Original assignee: Hatch Pty Ltd
Priority date: 2016-02-18
Filing date: 2017-02-13
Publication date: 2017-08-24
Also published as: AU2017220378A1; BR112018016823A2; SA518392207B1

Abstract

A wear liner (100) comprising an external sleeve (102), an internal sleeve (104) and a leak detection means (106) located at least in part therebetween, whereby a breach of the internal sleeve (104) by a fluid is detected by the leak detection means (106). A method of combatting wear using the wear liner (100) is also described.

Description

"Wear Liner and a Method for Combatting Wear"

Field of the Invention

[0001 ] The present invention relates to a wear liner and a method for combatting wear.

[0002] More particularly, the wear liner and the method for combatting wear of the present invention are intended for use in pressure systems such as may be employed in alumina refineries, for example.

Background Art

[0003] In chemical and process engineering applications utilising piping systems, particularly those that operate at pressure, there may be significant problems that arise from wear of the components comprising the piping system. Similar problems may present for other components that operate at pressure, such a pressure vessels. For example, many piping systems within the high pressure components of an alumina refinery incorporate orifices or 'chokes' in the piping system designed to reduce the fluid pressure therein. In the area immediately after the orifice plate or choke, powerful eddies are formed. These eddies extend some distance into the flow after the orifice plate or choke. It is the formation of such eddies that reduces pressure in the fluid. However, these eddies also result in frictional energy losses.

[0004] In fluid systems where solids particles are integral with the flowing fluid, again as may be experienced in alumina refineries, the eddies that are formed after the orifice can be highly erosive. Erosion can be exacerbated if the fluid pressure is reduced to the vapour pressure of the fluid whereby the fluid 'flashes' or boils, and releases steam.

[0005] Typically, piping systems are protected from wearing through the pipe wall after the orifice or choke by incorporating weld overlays of hardened metal alloys on the inside surface of these pipes. Another current option is the incorporation of clad piping spools with sacrificial liners. These liners are often formed of Hi- chromium content metal alloys, also referred to as "Chrome Carbide", or metals alloyed with nickel, for example. As the wear rates are not predictable with a high degree of certainty, personnel are required to perform periodic external thickness checks on selected areas of critical piping such that early detection of impending failure can be provided. Where weld overlays and/or sacrificial liners are incorporated into the piping however, external thickness checks are clearly limited in the accuracy of erosion detection possible.

[0006] The liners of some mining equipment, such as the wear liners or wear components (such as a block or tile) employed in transfer chutes, hoppers and deflectors for the passage of ore, have been provided with visual wear indicators and, most recently, electronic wear indicators that can be monitored remotely. The visual indicator utilised in these applications may comprise a wear liner component moulded with some visually apparent indicator, such as a slot or separately coloured portion, that indicates to an observer when that wear liner component needs to be replaced. One electronic indicator of the prior art comprises a sensor that extends through the full depth of the wear liner component that wears as the wear liner wears and is intended to communicate that wear to a computer that in turn provides an operator with an indication of the extent of the wear, such as a percentage of the thickness of the wear component. Another form of electronic indicator postulated has described a wear component similar to that described above in which there is provided a portion of layer that is of a different colour or texture. A camera or other sensor is then provided that is trained on the wear component, from a distance, in order to detect when that differently coloured portion of the wear component is exposed through the wearing of the component.

[0007] The visual indicators of the prior art require that the wear liner be observed, typically whilst operations have been halted to allow the inspection and are clearly either inappropriate or highly inconvenient for use in fluid piping systems. Electronic indicators are susceptible to breakages, given their electronic and consequently delicate nature, and their direct exposure to the material being transferred, providing either no reading or ambiguous readings as a result.

[0008] The present invention has as one object thereof to overcome substantially one or more of the abovementioned problems of the prior art, or to at least provide a useful alternative thereto.

[0009] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge in Australia or any other country or region as at the priority date of the application.

[0010] Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

[001 1 ] It is to be understood that reference to a pipeline hereinafter includes reference to a portion of a pipeline that terminates at a vessel and into which the fluid passing through the pipeline is directed. Further, the term pipeline or variations thereof should also be understood to broadly include any means by which a fluid is conveyed from one point to another.

Disclosure of the Invention

[0012] In accordance with the present invention there is provided a wear liner comprising an external sleeve, an internal sleeve and a leak detection means located at least in part therebetween, whereby a breach of the internal sleeve by a fluid is detected by the leak detection means.

[0013] Preferably, the leak detection means is provided in part in the form of a cavity between the internal and external sleeves. The cavity preferably extends substantially the full length of the internal sleeve.

[0014] The leak detection means preferably further comprises at least one indicator means.

[0015] The wear liner preferably further comprises an annular flange extending about a first end of the wear liner. The wear liner still preferably comprises an annular tapered terminal portion provided at a second end of the wear liner. The internal and external sleeves, and the cavity provided therebetween, form an elongate mid-section of the wear liner.

[0016] In one form, the wear liner still preferably further comprises a pair of annular collars, a first collar being provided at the first end thereof and a second collar being provided at the second end thereof. The first collar facilitating the location of the flange and the internal and external sleeves at the first end thereof whereas the second collar facilitates the location of the internal and external sleeves and the terminal portion.

[0017] In one form of the present invention the indicator means comprises one or more pressure sensors. In a further form of the present invention the indicator means comprises a telltale.

[0018] The or each pressure sensor is provided in the annular flange. An intermediate passage is preferably provided that communicates between each pressure sensor and the cavity between the internal and external sleeves.

[0019] The wear liner of the present invention is proportioned to be positioned in a pipeline at a join between two sections of pipe and between which is located a choke means. The wear liner is preferably fitted into a bore of one section of pipe located downstream from the choke means whereby the flange of the wear liner is positioned between the flanges of the two sections of pipe and by which they are attached.

[0020] Preferably, the terminal portion of the wear liner tapers or narrows in the same direction as the fluid flow, that is in a downstream direction from the choke means.

[0021 ] In one form, an inner collar is provided between the inner sleeve and the cavity. The inner collar preferably has a flange provided at one end thereof by which it engages the outer sleeve, thereby forming a pressure chamber. The pressure chamber encloses the cavity.

[0022] An abrasion collar is preferably provided within the pressure chamber. The abrasion collar is further preferably provided as a loose fit within the external sleeve.

[0023] Preferably, the internal sleeve is formed of Hi-chromium iron.

[0024] In accordance with the present invention there is further provided a method of combatting wear in a pipeline, the method comprising the fitting of a wear liner as described hereinabove into the pipeline such that the wear liner is oriented downstream with respect to the fluid flow in the pipeline.

[0025] In one form of the present invention the wear liner is provided at a join between sections of the pipeline. [0026] In another form of the present invention the wear liner is provided at a point at which a pipeline meets a nozzle in a vessel.

Brief Description of the Drawings

[0027] The wear liner and method of the present invention will now be described, by way of example only, with reference to two embodiments thereof and the accompanying drawings, in which:-

Figure 1 is a cross-sectional view of a portion of a pipeline in which a choke means is located, in which is shown the eddies generated in the flow through the pipeline immediately after the choke means, in accordance with the prior art;

Figure 2 is a cross-sectional view through a wear liner in accordance with a first embodiment of the present invention, in which the indicator means is provided in the form of a pressure switch;

Figure 3 is an exploded cross-sectional view through the wear liner of Figure 2, shown without the indicator means being present;

Figure 4 is a cross-sectional view of the wear liner of Figures 2 and 3 in position in a portion of a pipeline in which a choke means is located, showing the manner in which the eddies generated in the flow through the pipeline immediately after the choke means impinge on the internal sleeve of the wear liner;

Figure 5 is a cross-sectional view through a wear liner in accordance with a second embodiment of the present invention, in which the indicator means is provided in the form of a telltale;

Figure 6 is a cross-sectional view of a wear liner in accordance with a third embodiment of the present invention, shown without an indicator means fitted thereto;

Figure 7 is an exploded cross-sectional view through the wear liner of Figure 6, again without an indicator means; Figure 8 is an exploded cross-sectional view through a portion of the wear liner of Figures 6 and 7, showing in greater detail the construction and arrangement of the components thereof; and

Figure 9 is a cross-sectional view through Feature A of the the wear liner identified in Figure 6 being an external sleeve, an internal sleeve and a portion of the leak detection means therebetween.

Best Mode(s) for Carrying Out the Invention

[0028] In Figure 1 there is shown a prior art arrangement of a choke means, for example an annular choke 10, provided in a pipeline 12 comprising in part a first pipe section 14 and a second pipe section 1 6. The flow of a fluid through the pipeline 12 is indicated by arrows 1 8. As the flow 18 passes through an aperture 20 defined by the choke 10 the flow forms eddies 22. As noted above, the incorporation of the choke means is intended to reduce fluid pressure in the pipeline 12. The eddies 22 formed in the flow 18 reduces the pressure of the fluid but the eddies 22 can be highly erosive, particularly in fluids having a significant solids content, such as are present in alumina refineries.

[0029] The pipe sections 14 and 1 6 each have provided at their ends a flange 24 by which the pipe sections may be connected and fastened to one another. The annular choke 1 0 is positioned and fastened between the flanges 24 of the first pipe section 14 and the second pipe section 16.

[0030] In Figures 2 to 4 there is shown a wear liner 40 in accordance with a first embodiment of the present invention. The wear liner 40 comprises an external sleeve 42, an internal sleeve 44 and a leak detection means 46 located therebetween, whereby the breaching of the internal sleeve 44 by a fluid is detected by the leak detection means 46.

[0031 ] The leak detection means 46 comprises in part a cavity 48. The cavity 48 is generally located between the external and internal sleeves, 42 and 44 respectively, as is best seen in Figure 2. The cavity 48 extends substantially the full length of the internal sleeve 44.

[0032] The leak detection means 46 further comprises at least one indicator means 50. [0033] The wear liner 40 further comprises an annular flange 52 extending about a first end 54 of the wear liner 40. The wear liner 40 comprises an annular tapered terminal portion 56 provided at a second end 58 of the wear liner 40. The external and internal sleeves, 42 and 44 respectively, and the cavity 48 provided therebetween, form an elongate mid-section 60 of the wear liner 40.

[0034] The wear liner 40 further comprises a pair of annular collars, a first collar 62 being provided at the first end 54 thereof and a second collar 64 being provided at the second end 58 thereof. The first collar 62 facilitating the location of the flange 52 and the external and internal sleeves, 42 and 44 respectively, at the first end 54 thereof, whereas the second collar 64 facilitates the location of the external and internal sleeves, 42 and 44 respectively, and the terminal portion 56.

[0035] The internal sleeve 44 is formed of Hi-chromium iron which is able to be bonded to the mild steel components of the wear liner 40 through the use of CAST-bonding techniques. The Hi-chromium iron provides a significantly wear resistant surface against which the eddies 22 formed in the fluid flow act.

[0036] The external sleeve 42 is in turn comprised of an outer thickness or portion 43 formed of carbon steel and an inner thickness or portion 45 formed of Hi- chromium iron, best seen in Figure 3.

[0037] The terminal portion 56 is in turn comprised of an outer thickness or portion 57 formed of carbon steel and an inner thickness or portion 59 formed of Hi- chromium iron, the portions 57 and 59 being CAST-bonded, again best seen in Figure 3.

[0038] The flange 52 and the collars 62 and 64 are formed of carbon steel.

[0039] The components of the wear liner 40 are welded together through the carbon steel components, being the flange 52, the carbon steel collars 62 and 64, the outer portion of the external sleeve 42, and the outer portion 57 of the terminal portion 56.

[0040] The indicator means 50 further comprises two pressure sensors 66, again best seen in Figure 2. The pressure sensors 66 are fitted to a circumference 68 of the annular flange 52, for example through complimentary threaded engagement. Intermediate passages 70 are provided that extend radially through the width of the annular flange 52 to the cavity 48, thereby facilitating communication, for example fluid communication, between the sensors 66 and the cavity 48.

[0041 ] The terminal portion 56 of the wear liner 40 tapers or narrows in the same direction as the fluid flow 1 8, that is in a downstream direction from the choke means 10, as is best seen in Figure 4. The tapering of the terminal portion 56 in this manner facilitates smooth fluid flow 18 away, in a downstream direction, from the wear liner 40.

[0042] The wear liner 40 is proportioned to be positioned in a pipeline, for example the pipeline 12 of Figure 1 , at the join between the two sections of pipe 14 and 16, and between which is located the annular choke 10, as is again best seen in Figure 4 The wear liner 40 is fitted into a bore of the pipe section 1 6 located downstream from the annular choke 10 whereby the flange 52 of the wear liner 40 is positioned between the flanges 24 of the two sections of pipe 14 and 16, and to which they are attached.

[0043] As the fluid flow 18 passes through the aperture 20 of the annular choke 10 eddies 22 are formed downstream thereof, as seen in Figure 4. The eddies 22 impinge on the internal sleeve 44. Whilst the Hi-chromium iron from which the internal sleeve 44 is formed is very wear resistant it will wear over time. If the internal sleeve 44 is breached the fluid being conveyed through the pipeline 1 2 enters the cavity 48, passing therethrough and into the intermediate passages 70, after which it engages with and triggers the pressure switches 66 providing an indication to one or more users (not shown) that a leak has occurred and that the wear liner 40 may require replacement.

[0044] The provision of the inner portion 45 of the external sleeve 42 in Hi- chromium iron provides additional wear life after the point at which the user has received an indication of wear, as described above. This allows the user(s) time to isolate major equipment items prior to what may be the complete rupture or failure of the pipeline 12.

[0045] In Figure 5 there is shown a wear liner 80 in accordance with a second embodiment of the present invention. The wear liner 80 is substantially similar to the wear liner 40 and like numerals denote like parts. [0046] The indicator means 50 of the wear liner 80 further comprises two connecting lines 82 that connect the intermediate passages 70 respectively to a telltale outlet line 84. The connecting lines 82 are fitted to the circumference 68 of the annular flange 52. The intermediate passages 70 extend radially outward through the width of the annular flange 52 to the cavity 48 thereby facilitating communication between the cavity 48, the connecting lines 82 and, in turn, the telltale line 84.

[0047] The method by which the wear liner 80 operates is substantially similar to that of the wear liner 40 described hereinabove, other than as the internal sleeve 44 is breached the fluid being conveyed through the pipeline 12 enters the cavity 48, passing therethrough and into the intermediate passages 70, after which it flows through the connecting lines 82 to the telltale outlet line 84, thereby providing an indication to a user (not shown) that a leak has occurred and that the wear liner 80 requires replacement. The telltale outlet line 84 provides a safe discharge location away from personnel such that a visible discharge from the outlet line 84 alerts personnel to the wear liner failure prior to damage of piping and/or equipment.

[0048] In Figures 6 to 8 there is shown a wear liner 100 in accordance with a third embodiment of the present invention. The wear liner 1 00 is substantially similar to the wear liners 40 and 80 in many respects and like numerals denote like parts.

[0049] The wear liner 100 comprises an external sleeve 102, an internal sleeve 1 04 and a leak detection means 106 located therebetween, whereby the breeching of the internal sleeve 1 04 by a fluid is detected by the leak detection means 1 06.

[0050] The leak detection means 1 06 is provided in part in the form of a cavity 108 located generally between the external and internal sleeves, 1 02 and 104 respectively, as is best seen in Figure 6. The cavity 108 extends substantially the full length of the internal sleeve 1 04.

[0051 ] The leak detection means 1 06 further comprises an indicator means (not shown).

[0052] The wear liner 1 00 further comprises an annular flange 1 10 extending about a first end 54 of the wear liner 100. The wear liner 100 still further comprises an annular tapered terminal portion 56 provided at a second end 58 of the wear liner 100. The external and internal sleeves, 1 02 and 1 04 respectively, and the cavity 108 provided generally therebetween, comprise a portion of an elongate mid-section 1 1 2 of the wear liner 1 00.

[0053] The elongate mid-section 1 12 of the wear liner 100 further comprises, located between the external and internal sleeves, 1 02 and 1 04 respectively, an inner collar 1 14 and an abrasion collar 1 16. The cavity 108 is located between the inner collar 1 14 and the abrasion collar 1 16 and is aligned to join, or be contiguous with, the intermediate passages 70 that extend through the width of the annular flange 1 10 thereby facilitating communication therebetween.

[0054] The inner collar 1 14 has provided at one end a radial flange 120, best seen in Figure 7. By way of the radial flange 120 the inner collar 1 14 is bonded to external sleeve 102, forming a pressure chamber 1 22, best seen in Figure 8. As shown in Figure 6, the abrasion collar 1 1 6 is located within the pressure chamber 1 22 and is provided in a diameter such that it abuts in a loose fit the external sleeve 1 02. In this manner the portion of the cavity 108 that communicates with the intermediate passages 70 is located between the abrasion collar 1 16 and the inner collar 1 14.

[0055] The wear liner 1 00 does not require the annular collars of the wear liner 40.

[0056] Importantly, the external sleeve 102 and the inner collar 1 14 that form the pressure chamber 1 22 are formed from carbon steel capable of withstanding pressure levels likely to be experienced by the wear liner 100 in use. However, the abrasion collar 1 16 provided within the pressure chamber 1 22 is formed of Hi- chromium iron, which provides a significantly wear resistant surface. Similarly, the internal sleeve 104 is also formed of Hi-chromium iron to provide a wear resistant surface against the eddies 22 that form as fluid flows through the wear liner 100 in use.

[0057] The terminal portion 56 of wear liner 1 00 is again in turn comprised of an outer thickness or portion 57 formed of carbon steel and an inner thickness or portion 59 formed of Hi-chromium iron, the portions 57 and 59 being CAST- bonded, as is best seen in Figure 7.

[0058] The flange 1 12 is formed of carbon steel. [0059] A number of components of the wear liner 100 are welded together through the carbon steel components, being the flange 1 12, the external sleeve 1 02, and the outer portion 57 of the terminal portion 56. The internal sleeve 104 is provided as a loose fit and is not bonded to the carbon steel of the flange 1 1 2 or inner collar 1 14 of the pressure chamber 122.

[0060] An external housing 1 18 may be provided about the wear liner 1 00 as shown in Figure 6 but is suitable only for use in certain applications, such as for use as a nozzle for directing fluid flow into a container or tank. The use of an external housing such as that shown in Figure 6 is not necessarily intended for use of the wear liner 100 in a pipeline.

[0061 ] It is to be understood that the wear liner 100 will incorporate, in use, at least one indicator means. Further, the indicator means of the wear liner 100 may clearly be provided in the two forms described hereinabove in respect of the indicator means 50 of the wear liners 40 and 80 of the present invention.

[0062] The wear liner 100 operates in use in much the same manner as the wear liner 40. Similarly, eddies formed in the fluid flow impinge on the internal sleeve 1 04. As noted in respect of wear liner 40, whilst the Hi-chromium iron of the internal sleeve 104 is very wear resistant it will wear over time. If the internal sleeve 104 is breached the fluid being conveyed enters the cavity 108, passing therethrough and into the intermediate passages 70, after which it engages with and triggers the indicator means (not shown) thereby providing an indication to one or more users (not shown) that a leak has occurred and that the wear liner 1 00 may require replacement.

[0063] In the wear liner 1 00 the provision of the abrasion collar 1 1 6 in Hi- chromium iron within the pressure chamber 1 22 provides additional wear life after the point at which the user has received an indication of wear, as described above. This allows the user(s) time to isolate major equipment items prior to what may be the complete rupture or failure of a pipeline in which the wear liner 1 00 is provided.

[0064] As can be seen with reference to the above description, the wear liner and method of combatting wear of the present invention provide both apparatus and methods by which personnel, such as may be employed in operating an alumina refinery, are protected from inadvertent release of high temperature and high pressure fluids. Further, piping and/or equipment integrity is able to be maintained more effectively and efficiently than it is in prior art systems.

[0065] It is envisaged that the indicator means may be provided in a form other than the pressure sensor(s) and telltale described hereinabove. For example, an electrical and/or chemical mechanism may be utilised.

[0066] Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention.

Claims

1 . A wear liner comprising an external sleeve, an internal sleeve and a leak detection means located at least in part therebetween, whereby a breach of the internal sleeve by a fluid is detected by the leak detection means.

2. A wear liner according to claim 1 , wherein the leak detection means is provided in part in the form of a cavity between the internal and external sleeves.

3. A wear liner according to claim 2, wherein the cavity extends substantially the full length of the internal sleeve.

4. A wear liner according to any one of the preceding claims, wherein the leak detection means further comprises at least one indicator means.

5. A wear liner according to any one of the preceding claims, wherein the wear liner further comprises an annular flange extending about a first end of the wear liner.

6. A wear liner according to claim 5, wherein the wear liner further comprises an annular tapered terminal portion provided at a second end of the wear liner.

7. A wear liner according to any one of claims 1 to 6, wherein the internal and external sleeves, and the cavity provided therebetween, form an elongate midsection of the wear liner.

8. A wear liner according to any one of the preceding claims, wherein the wear liner further comprises a pair of annular collars, a first collar being provided at the first end thereof and a second collar being provided at the second end thereof.

9. A wear liner according to claim 8, wherein the first collar facilitates the location of the flange and the internal and external sleeves at the first end thereof whereas the second collar facilitates the location of the internal and external sleeves and the terminal portion.

1 0. A wear liner according to any one of claims 4 to 9, wherein the indicator means comprises: a. one or more pressure sensors; or b. a telltale.

1 1 . A wear liner according to claim 10, wherein the or each pressure sensor is provided in the annular flange.

1 2. A wear liner according to claim 1 1 , wherein an intermediate passage is provided that communicates between each pressure sensor and the cavity between the internal and external sleeves.

1 3. A wear liner according to any one of the preceding claims, wherein the wear liner is proportioned to be positioned in a pipeline at a join between two sections of pipe and between which is located a choke means.

14. A wear liner according to claim 1 3, wherein the wear liner is fitted into a bore of one section of pipe located downstream from the choke means whereby the flange of the wear liner is positioned between the flanges of the two sections of pipe and by which they are attached.

1 5. A wear liner according to claim 14, wherein the terminal portion of the wear liner tapers or narrows in the same direction as the fluid flow, that is in a downstream direction from the choke means.

1 6. A wear liner according to any one of the preceding claims, wherein an inner collar is provided between the inner sleeve and the cavity.

1 7. A wear liner according to claim 16, wherein the inner collar has a flange provided at one end thereof by which it engages the outer sleeve, thereby forming a pressure chamber, the pressure chamber enclosing the cavity.

1 8. A wear liner according to claim 17, wherein an abrasion collar is provided within the pressure chamber.

1 9. A wear liner according to claim 1 8, wherein the abrasion collar is provided as a loose fit within the external sleeve.

20. A wear liner according to any one of the preceding claims, wherein the internal sleeve is formed of Hi-chromium iron.

21 . A method of combatting wear in a pipeline, the method comprising the fitting of a wear liner according to any one of the preceding claims into the pipeline such that the wear liner is oriented downstream with respect to the fluid flow in the pipeline.

22. A method according to claim 21 , wherein the wear liner is provided at a join between sections of the pipeline.

23. A method according to claim 21 or 22, wherein the wear liner is provided at a point at which a pipeline meets a nozzle in a vessel.