CN112382475A - Bellows type respirator and transformer oil storage tank - Google Patents

Abstract

The invention provides a corrugated pipe type respirator and a transformer oil storage tank, so that the maintenance-free time of the transformer oil storage tank is prolonged, and the maintenance cost is reduced; the structure of the bellows type respirator comprises: the breather valve is provided with an air inlet and outlet channel; further comprising: a metal bellows; one end of the metal corrugated pipe is hermetically connected with the breather valve, and the air inlet and outlet channel is communicated with the inner cavity of the metal corrugated pipe; the port at the other end of the metal corrugated pipe is sealed by arranging an end cover in a welding manner; the acting force required by the stretching and the contraction of the metal corrugated pipe is matched with the atmospheric pressure generated when the internal and external pressure of the metal corrugated pipe changes. The transformer oil storage tank also comprises the corrugated pipe type breather; after the corrugated pipe type respirator is assembled with the box body, the metal corrugated pipe of the corrugated pipe type respirator is positioned in the box body, and one end, used for air inlet and exhaust, of a breather valve of the corrugated pipe type respirator is positioned outside the box body. The invention solves the technical problem of prolonging the maintenance-free operation time of the transformer.

Description

Bellows type respirator and transformer oil storage tank

Technical Field

The invention relates to the technical field of transformer oil tanks, in particular to a corrugated pipe type respirator and a transformer oil tank.

Background

In the early application stage of the transformer, the pressure in the oil tank of the transformer cannot be adjusted in a self-adaptive manner under the influence of the oil temperature change, so that the sealing performance of the oil tank is adversely affected when the pressure in the oil tank changes, and even the oil tank is deformed in severe cases, thereby causing the sealing failure of a sealing part. In order to solve the above technical problems, a conventional method in the prior art is to provide a breather on an oil storage tank of a transformer, and the breather keeps the inside and the outside of the transformer in conduction, so as to realize pressure balance between the inside and the outside of the transformer. Set up the respirator in the transformer oil storage tank among the prior art and for preventing that the inside moisture absorption silica gel or the rubber gasbag that adopt of steam in the air gets into the transformer usually as core work part, though can solve the technical problem of the inside and outside pressure difference of balanced oil tank to a certain extent, but silica gel uses for a certain time after, because the moisture absorption can take place to absorb moisture in the air and become invalid, continue to use and can lead to the steam in the air to get into transformer fluid, can lead to transformer oil insulating properties to descend when serious, and then cause the transformer trouble. Therefore, in the prior art, when the transformer oil storage tank is maintained, the rubber air bag in the transformer oil storage tank or the color-changing silica gel in the respirator needs to be replaced regularly, so that the daily maintenance cost of the transformer oil storage tank is increased to a certain extent, and the economic burden of an enterprise is increased by replacing the transformer oil storage tank. In the rubber bladder system, the bladder in the oil reservoir needs to be replaced periodically due to the decrease in elasticity caused by the aging of rubber.

Therefore, it is necessary to develop a bellows type breather and a transformer oil tank to solve the above technical problems.

Disclosure of Invention

The invention aims to provide a corrugated pipe type breather and a transformer oil storage tank, so that the maintenance-free use effect of the transformer oil storage tank is achieved, and the use cost of a transformer is reduced.

The above object of the present invention can be achieved by the following technical solutions:

in one aspect, the present invention provides a bellows respirator comprising: the breather valve is provided with an air inlet and outlet channel; further comprising: a metal bellows; one end of the metal corrugated pipe is connected with the breather valve, and the air inlet and outlet channel is communicated with the inner cavity of the metal corrugated pipe; an end cover is arranged at the port at the other end of the metal corrugated pipe in a sealing welding connection mode; the acting force required by the stretching and the contraction of the metal corrugated pipe is matched with the atmospheric pressure generated when the internal and external pressure of the metal corrugated pipe is changed.

Preferably, the end cap is integrally connected with the metal bellows.

Preferably, the end cover is connected with the metal corrugated pipe in a welding mode.

Preferably, the upper end of the metal corrugated pipe is a stainless steel plate with the thickness larger than the pipe wall of the corrugated pipe, the breather valve is welded on the stainless steel plate, and the air inlet and outlet channel is communicated with the inner cavity of the metal corrugated pipe; the lower end of the metal corrugated pipe is welded with a completely sealed end cover made of the same material as the corrugated pipe.

Preferably, the breather valve and the bellows are all sealed in a welding mode.

Preferably, the metal corrugated pipe is made of stainless steel sheets, the connection of the corrugated parts is realized between two adjacent stainless steel sheets on the metal corrugated pipe in a laser welding or plasma welding mode, and the metal corrugated pipe has sensitivity to pressure change and hysteresis for improving the internal and external pressure adaptation of the transformer.

Preferably, one end of the air inlet and outlet channel of the breather valve is arranged on the side wall of the end part of the top end of the breather valve; the other end of the air inlet and outlet channel of the breather valve is arranged on the bottom surface of the end part of the lower end of the breather valve.

Preferably, the breather valve is provided with a connecting part for being hermetically connected with a transformer oil storage tank body.

Preferably, the breather valve has an opening and closing function, and is convenient for the installation and the disassembly of the metal corrugated pipe.

Preferably, the breather valve is provided with a dust cover, and has a dust prevention function.

Preferably, the top end cover of the bellows type respirator is directly welded on the bellows, and the peripheral extension part of the top end cover is used for being fixedly connected with the transformer oil storage tank body in a direct welding mode.

Preferably, a flange is welded at the upper end of the metal corrugated pipe; and the lower end face of the flange is provided with a mechanical seal which is used for being matched with the appearance of a respirator assembly port arranged on the transformer oil storage tank.

Preferably, the upper end of the metal corrugated pipe is hermetically connected with a flange; the inner ring of the flange is hermetically connected with the breather valve; and the lower end face of the flange is provided with a mechanical seal which is used for being matched with the appearance of a respirator assembly port arranged on the transformer oil storage tank.

Preferably, the mechanical sealing part is provided with a sealing gasket.

In another aspect, the invention further provides a transformer oil tank, further comprising the bellows type breather; after the corrugated pipe type respirator is assembled with the box body, the metal corrugated pipe of the corrugated pipe type respirator is positioned in the box body, and one end, used for air inlet and exhaust, of a breather valve of the corrugated pipe type respirator is positioned outside the box body.

Preferably, the side wall of the box body is provided with a perspective window.

Preferably, the bellows-type respirator is provided with a dust cover.

Preferably, the bellows type respirator and the box body are integrally connected in a welding mode.

The invention has the characteristics and advantages that:

the bellows type respirator provided by the invention can adaptively adjust the size of the space occupied by the bellows type respirator in the transformer oil storage tank according to the pressure change in the transformer oil storage tank, and the breathing valve arranged at the upper end of the metal bellows can adaptively select to breathe or exhaust according to the pressure change in the inner cavity of the metal bellows. The metal corrugated pipe is used as a carrier of the gas storage space, so that the service life of the oil storage tank is greatly prolonged compared with that of a rubber air bag, the maintenance-free time of the oil storage tank of the transformer can be greatly prolonged, and the operation cost for maintaining the oil storage tank of the transformer is reduced. Furthermore, because the metal corrugated pipe is of a pure sealing structure and is in mechanical sealing connection or welding connection with the transformer oil storage tank, the adaptability of the metal corrugated pipe to outdoor severe environments is greatly improved, adverse effects of wind, sand, rain, snow and other severe weather on the transformer oil storage tank can be effectively resisted, and the maintenance-free operation time of the transformer is prolonged. The invention is very suitable for the transformer which runs under extreme environmental conditions, in particular to the application of railway rolling stocks, wind power transformers, especially offshore wind power transformers, and transformers under other extreme environmental conditions.

Furthermore, one end of an air inlet and outlet channel of the breather valve is arranged on the side wall of the end part of the top end of the breather valve; the other end of the air inlet and outlet channel of the breather valve is arranged on the bottom surface of the end part of the lower end of the breather valve, so that adverse effects of wind, sand, rain and snow on the normal operation of the breather valve can be effectively inhibited, and the occurrence of the event that the breather valve fails in function due to sand blockage of the breather valve is avoided.

Further, when the transformer oil storage tank is provided with convenient to detach's upper cover, the connecting portion of setting on the breather valve can be convenient with corrugated tube respirator and oil tank upper cover fastening connection, help installing the corrugated tube respirator on the corrugated tube respirator in the transformer oil storage tank with the help of the upper cover.

Furthermore, the flange is arranged at the upper end of the metal corrugated pipe, so that the corrugated pipe type respirator can be conveniently overhauled and replaced, and the corrugated pipe type respirator can be detached from the transformer oil storage tank only by removing the flange connection between the corrugated pipe type respirator and the transformer oil storage tank during maintenance.

The transformer oil storage tank further provided by the invention can self-adaptively balance the air pressure difference inside and outside the transformer oil storage tank, and ensure that the tank body of the transformer oil storage tank is not deformed due to the oil temperature change in the transformer. Furthermore, after the corrugated pipe type breather is adopted, the maintenance-free time of the breather of the transformer oil storage tank can be greatly prolonged, and the maintenance cost of the transformer is reduced. When the oil storage tank is used, the metal corrugated pipe can actively balance internal and external pressures in a self-lifting mode along the axis direction according to the internal and external pressure differences of the oil storage tank of the transformer, and the appearance of the tank body of the oil storage tank of the transformer is not affected by the change of the oil temperature in the transformer. In addition, the metal corrugated pipe automatically balances the internal and external air pressures in an up-and-down automatic telescopic mode, so that the air tightness in the transformer oil storage tank can be fully guaranteed, moisture in the air is prevented from entering transformer oil, the service life is long, the aging function is not easy to lose efficacy, and the operation burden of transformer maintenance personnel can be greatly reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view showing the structure of a bellows type respirator in example 1 of the present invention;

FIG. 2 is a schematic view showing a modified structure of a bellows type respirator in example 1 of the present invention;

FIG. 3 is a schematic view showing another modified structure of the bellows type respirator in example 1 of the present invention;

FIG. 4 is a schematic structural view of a tank for storing oil of a transformer in embodiment 2 of the present invention;

FIG. 5 is a schematic view showing an improved structure of a transformer oil reservoir in embodiment 2 of the present invention;

fig. 6 is a schematic view of another modified structure of the oil tank of the transformer in embodiment 2 of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; the connection can be mechanical connection or welding; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1:

as shown in FIG. 1, the present invention provides a bellows-type respirator that comprises: the breathing valve 100, the breathing valve 100 is provided with an air inlet and outlet channel 110; further comprising: a metal bellows 200; one end of the metal corrugated pipe 200 is hermetically connected with the breather valve 100, and the air inlet and outlet channel is communicated with the inner cavity of the metal corrugated pipe 200; an end cover in sealing connection is arranged at the port of the other end of the metal corrugated pipe 200; the acting force required by the stretching and the contraction of the metal corrugated pipe is matched with the atmospheric pressure generated when the internal and external pressure of the metal corrugated pipe is changed.

The bellows type respirator provided by the invention can adaptively adjust the size of the space occupied by the bellows type respirator in the transformer oil storage tank according to the pressure change in the transformer oil storage tank, and the breathing valve arranged at the upper end of the metal bellows can adaptively select to breathe or exhaust according to the pressure change in the inner cavity of the metal bellows. The metal corrugated pipe is used as a carrier of the gas storage space, so that the service life of the oil storage tank is greatly prolonged compared with that of a plastic air bag, the maintenance-free time of the transformer oil storage tank can be greatly prolonged, and the operation cost for maintaining the transformer oil storage tank is reduced. Furthermore, because the metal corrugated pipe is of a pure sealing structure and is in mechanical sealing connection with the transformer oil storage tank, the adaptability of the metal corrugated pipe to outdoor severe environments is greatly improved, adverse effects of wind, sand, rain, snow and other severe weather on the transformer oil storage tank can be effectively resisted, and the maintenance-free operation time of the transformer is prolonged.

Preferably, in one preferred technical solution of this embodiment, the upper end of the metal bellows is a stainless steel plate with a thickness greater than the wall of the bellows, the breather valve is welded to the stainless steel plate, and the air intake and exhaust passage is communicated with an inner cavity of the metal bellows; the lower end of the metal corrugated pipe is welded with a completely sealed end cover made of the same material as the corrugated pipe.

Preferably, in one preferred technical solution of this embodiment, the metal bellows is formed by laser welding or plasma welding a stainless steel sheet, one end of the bellows is welded to an end cap of the oil storage tank, and the other end of the bellows is sealed by the end cap and then is hermetically connected to the port in a welding manner. Preferably, after welding, a helium gas leakage detection mode is adopted to detect whether each connecting part on the metal corrugated pipe meets the air tightness standard.

Preferably, in one preferable technical solution of this embodiment, the end cap is integrally connected to the metal bellows. Preferably, the integral connection is realized by welding.

Preferably, as shown in fig. 1, in one preferred technical solution of the present embodiment, one end of the air intake and exhaust channel 110 of the breather valve 100 is disposed on a side wall of a top end of the breather valve; the other end of the air inlet and outlet channel of the breather valve is arranged on the bottom surface of the end part of the lower end of the breather valve. Preferably, the top end of the side wall of the top end of the breather valve is circumferentially provided with a plurality of air holes, and the plurality of air holes are respectively communicated with the air inlet and outlet channel 110. One end of an air inlet and outlet channel of the breather valve is arranged on the side wall of the end part of the top end of the breather valve; the other end of the air inlet and outlet channel of the breather valve is arranged on the bottom surface of the end part of the lower end of the breather valve, so that adverse effects of wind, sand, rain and snow on the normal operation of the breather valve can be effectively inhibited, and the occurrence of the event that the breather valve fails in function due to sand blockage of the breather valve is avoided.

Preferably, in one preferred technical solution of this embodiment, a breather valve is welded at the top end of the metal corrugated pipe, and an air intake and exhaust passage of the breather valve is communicated with an inner cavity of the metal corrugated pipe; the bottom end of the metal bellows is completely closed.

Preferably, as shown in fig. 2, in one preferred embodiment of the present invention, the breather valve 100 is provided with a connecting portion 120 for sealing connection with a tank of a transformer tank. When the transformer oil tank 300 is provided with the upper cover 310 which is convenient to detach, the connecting part 120 arranged on the breather valve can conveniently and fixedly connect the corrugated pipe type breather and the oil tank upper cover, and the metal corrugated pipe on the corrugated pipe type breather is favorably installed in the transformer oil tank by means of the upper cover. Preferably, as shown in fig. 2, a circumferential gasket or mechanical seal M is provided at a connection portion of the upper cover 310 and the transformer oil reservoir 300 to prevent water vapor in the air from entering the transformer oil reservoir from the connection portion and affecting the transformer oil.

Preferably, as shown in fig. 3, in one preferred technical solution of the present embodiment, a flange 210 is hermetically connected to an upper end of the metal corrugated pipe 200; the inner ring of the flange is hermetically connected with the breather valve 100; the lower end surface of the flange 210 is provided with a mechanical seal adapted to the shape of a breather fitting port 320 provided in the transformer tank 300. According to the invention, the flange is arranged at the upper end of the metal corrugated pipe, so that the corrugated pipe type respirator can be conveniently overhauled and replaced, and the corrugated pipe type respirator can be detached from the transformer oil storage tank only by removing the flange connection between the corrugated pipe type respirator and the transformer oil storage tank during maintenance.

Preferably, in one preferable technical solution of this embodiment, the mechanical sealing portion is provided with a gasket. Since the sealing structure is configured based on the prior art, the details of the related structure are not further illustrated and described herein.

Further, in one preferable technical solution of this embodiment, an outer shape of a cross section parallel to a horizontal plane after the metal corrugated tube is assembled is one of a circle, an ellipse, a rectangle, and a round-edged rectangle.

Example 2:

as shown in fig. 4, the present embodiment further provides a transformer oil storage tank based on embodiment 1, including a tank 1 having an oil passage connection end L at the bottom, where the L end is a flange interface for connecting to a transformer tank, and further including a bellows type breather 2 in the foregoing embodiment; after the corrugated pipe type respirator 2 and the box body 1 are assembled, the metal corrugated pipe of the corrugated pipe type respirator 2 is positioned in the box body 1, and one end, used for air inlet and exhaust, of a breather valve of the corrugated pipe type respirator 2 is positioned outside the box body 1.

When the transformer oil storage tank is used, the transformer tank body is communicated with the oil storage tank, when the volume of transformer oil changes due to the change of the oil temperature, the corrugated pipe inside the oil storage tank enables the pressure inside and outside the transformer to be kept balanced through expansion, and meanwhile, external air and water vapor are isolated.

The transformer oil storage tank further provided by the invention can self-adaptively balance the air pressure difference inside and outside the transformer oil storage tank, and ensure that the tank body of the transformer oil storage tank is not deformed due to the oil temperature change in the transformer. Furthermore, after the corrugated pipe type breather is adopted, the maintenance-free time of the breather of the transformer oil storage tank can be greatly prolonged, and the maintenance cost of the transformer is reduced. When the oil storage tank is used, the metal corrugated pipe can actively balance internal and external pressures in a self-lifting mode along the axis direction according to the internal and external pressure differences of the oil storage tank of the transformer, and the appearance of the tank body of the oil storage tank of the transformer is not affected by the change of the oil temperature in the transformer.

Further, in one of the preferable technical solutions of this embodiment, a hanging ring or a hanging hook structure for facilitating hanging is disposed on the upper end surface of the box body. It should be noted that the structure of the hanging ring or the hanging hook is configured in the prior art, and therefore, the details of the structure thereof are not further illustrated and described herein.

Further, in one preferable technical solution of this embodiment, the cross-sectional shape of the oil storage tank parallel to the horizontal plane after the assembly is completed is one of a circle, an ellipse, a rectangle, and a round-edged rectangle.

Further, as shown in fig. 4, in one preferred technical solution of this embodiment, a transparent window 3 is disposed on a side wall of the box body. The perspective window is arranged for observing the self-expansion change of the metal corrugated pipe in the transformer oil storage tank, and can observe the liquid level state of the transformer oil in the transformer oil storage tank in time, so that whether the corrugated pipe type respirator has hardware faults or not can be found in time.

Further, in one preferable technical solution of this embodiment, an electronic barometer is disposed in the box body. Whether the bellows type respirator normally works is helped to be analyzed by the arrangement of the electronic barometer, when the pressure difference between the air pressure in the box body and the outdoor air pressure exceeds a set threshold value, the bellows type respirator can be timely judged to break down, and a maintenance worker can timely maintain whether the breather valve is blocked or whether the telescopic function of the metal bellows is fatigue failure or not.

Further, as shown in fig. 5, in one preferred embodiment of the present embodiment, the bellows type respirator 2 is provided with a dust cover 4. The dust cover can effectively prevent dust in the air from blocking the air channel of the bellows type respirator, so that the maintenance-free effect of the transformer oil storage tank is more reliable. It should be noted that the structure of the dust cover is the prior art, and therefore, the detailed structural details thereof are not further illustrated and described herein. Alternatively, the dust cover is arranged at the air inlet part of the bellows type respirator in a dust-proof net mode, the same dust-proof effect can be obtained, and therefore the related structure is also claimed.

Further, as shown in fig. 6, in one preferred technical solution of this embodiment, the bellows type breather and the box body are connected in an integrated manner. Under one of the manufacturing modes, the upper end surface of the metal corrugated pipe of the corrugated pipe type respirator and the upper end surface of the box body can be integrated into a whole, and the sealing connection of the metal corrugated pipe and the box body is realized by adopting a welding mode. The corrugated pipe type respirator researched and developed by the invention has the service life which is nearly as long as that of a box body of a transformer oil storage tank, the maintenance cost of the transformer oil storage tank can be greatly reduced by adopting the integral connection of the corrugated pipe type respirator and the box body, and when the corrugated pipe type respirator breaks down, the maintenance task can be completed by only directly dismounting and replacing the transformer oil storage tank provided with the corrugated pipe type respirator, so that the work burden of maintenance personnel can be greatly reduced. In addition, above-mentioned structure can possess good leakproofness, can thoroughly isolate the contact between transformer oil and the outside air, and then has high operational reliability.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. A bellows type respirator comprises a breather valve, wherein the breather valve is provided with an air inlet and outlet channel; it is characterized by also comprising: a metal bellows; one end of the metal corrugated pipe is hermetically connected with the breather valve, and the air inlet and outlet channel is communicated with the inner cavity of the metal corrugated pipe; an end cover is arranged at the port at the other end of the metal corrugated pipe in a sealing welding connection mode; the acting force required by the stretching and the contraction of the metal corrugated pipe is matched with the atmospheric pressure generated when the internal and external pressure of the metal corrugated pipe is changed.

2. The bellows respirator of claim 1, wherein the end cap is integrally connected to the metal bellows.

3. The bellows respirator of claim 1, wherein one end of the inlet and outlet passageway of the breather valve is disposed in a side wall of the tip end of the breather valve; the other end of the air inlet and outlet channel of the breather valve is arranged on the bottom surface of the end part of the lower end of the breather valve.

4. The bellows type respirator of claim 1, wherein the upper end of the metal bellows is a stainless steel plate with a thickness larger than the wall of the metal bellows, the breather valve is welded on the stainless steel plate, and the air inlet and outlet channel is communicated with the inner cavity of the metal bellows; the lower end of the metal corrugated pipe is welded with a completely sealed end cover made of the same material as the corrugated pipe.

5. The bellows respirator of claim 1, wherein the metal bellows has a flange welded to an upper end thereof; and the lower end face of the flange is provided with a mechanical seal which is used for being matched with the appearance of a respirator assembly port arranged on the transformer oil storage tank.

6. The bellows respirator of claim 5, wherein the mechanical seal is provided with a gasket.

7. A transformer oil storage tank comprises a tank body, the bottom of which is provided with an oil passage connecting end, and the transformer oil storage tank is characterized by further comprising a bellows type respirator of any one of claims 1 to 6; after the corrugated pipe type respirator is assembled with the box body, the metal corrugated pipe of the corrugated pipe type respirator is positioned in the box body, and one end, used for air inlet and exhaust, of a breather valve of the corrugated pipe type respirator is positioned outside the box body.

8. The transformer tank of claim 7, wherein the side wall of the tank is provided with a see-through window.

9. The transformer tank of claim 7, wherein the bellows-type breather is provided with a dust shield.

10. The transformer tank of claim 7, wherein the bellows-type breather is integrally connected to the tank by welding.

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