NL8500296A - DEVICE FOR CLEANING A STEAM GENERATOR. - Google Patents

Description

"Device for cleaning a steam generator".

VO 7042

The invention relates to a device for cleaning a steam generator of the so-called U-type, which steam generator therefore contains an upright jacket, a pipe bundle mounted therein, in the form of an inverted 5 U, with an upright bundle part and a downward bundle part. , a bottom which closes at the bottom the openings between the pipes themselves and between the pipes and the jacket, which jacket above the bottom is provided with at least one access to the space between the two bundle parts, the cleaning device comprising a spray device which itself is a movable chassis which is movable between the bundle sections over the bottom and a nozzle holder which carries at least one nozzle and is movably mounted on this chassis, which cleaning device also contains a high-pressure hose which connects to the spraying device and through which liquid is pressurized from outside the generator on the nozzle k can be supplied.

Steam generators of the aforementioned type 20 are widely used in nuclear power plants. The heating fluid heated in the nuclear reactor is passed through the pipe bundle and relinquishes heat to the fluid, usually water, which is located in the space surrounding the pipes, creating steam. Due to various chemical reactions, an iron oxide, namely magnetite, is formed in the space around the pipe bundle. This iron oxide deposits on the pipe bundle, on the support plates that support this pipe bundle and especially on the bottom.

The iron oxide must be removed every time, usually annually, the nuclear power plant is serviced. Related to the difficult accessibility of the steam generator and especially roads? the prevailing radioactivity, the steam-BAD & ORtGtfNAL cannot be disassembled so that for the removal of the sludge and thus more specifically the iron oxide, special

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- 2 - devices are necessary.

Often use is made of a device which contains a rigid lance on one end of which the high-pressure hose connects and on another end of which a rotary nozzle is mounted which sprays through one or more openings in directions that are in a plane transverse to the lance are targeted.

The lance with the nozzle is moved intermittently in the space between the ascending and descending portion of the pipe bundle.

Such devices can very efficiently clean steam generators when the pipes of the pipe bundle are arranged according to a so-called square arrangement, ie the pipes are located at the intersections of a network of perpendicularly intersecting lines 15 which are respectively parallel to and extend perpendicular to the symmetry plane of this pipe bundle, situated in the middle of the space between the bundle parts of the pipe bundle.

However, steam generators are known in which the pipes of the bundle are arranged according to a so-called Chinese diamond arrangement and are thus located at the intersections of a network formed by lines not perpendicular to each other, which make an angle with the above-mentioned symmetry plane. Such steam generators are used, inter alia, in the K.W.U. nuclear power stations (Kraftwerk-Union-Centrales). In these known generators, each pipe can be considered to be part of three rows of pipes, namely a row of pipes oriented perpendicular to the plane of symmetry between the beam parts, a row making an angle of 30 ° to one side with this plane of symmetry and a third row making an angle of 30 ° to the opposite side with this plane of symmetry. Thus, there are also spaces extending in three directions between the pipes of a bundle section in order to clean such a pipe bundle. Moet »'f *" * jf>. Λ ·;' 'r;; ^ ,! ίΛ - 3 - be sprayed in three directions, namely in directions that make angles of 30 °, 90 ° and 150 ° with respect to the symmetry plane, since the spaces between the pipes which are oriented transversely to the aforementioned symmetry plane are free narrow and by spraying only in these spaces the cleaning would be insufficient.

Directing the water jet at an angle to the axis of rotation of the nozzle does not solve the problem, since the jet of water itself describes the water jet as a cone and does not move up and down in a space directed at an angle to the plane of symmetry.

It is well known for cleaning steam generators of the last-mentioned type to use a spraying device movable between the bundle parts with nozzles oriented at an angle to the displacement direction, but the nozzles are not rotated. In order to clean the spaces between the rows of pipes over a sufficient height above the bottom, the nozzles are moved up and down with their nozzle holder. This known device therefore comprises a base which can be moved over the bottom and a nozzle holder with stationary nozzles that can be moved up and down by means of a spindle mechanism. The undercarriage is displaced by means of rotating members which intervene between the pipes which define the space between the ascending and descending beam section. While moving the nozzle holder up and down, the undercarriage is held by hydraulic struts that clamp the undercarriage between the pipes of the rows defining the space between the bundle portions. Cleaning is not only relatively slow with this known device, but because both

for displacement as for holding the under-BAD ORIGINAL

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- 4 - When spraying this undercarriage on pipes of the pipe bundle, there is a risk that these pipes will be damaged.

The object of the invention is to overcome these drawbacks and to provide a device for cleaning a steam generator which is also suitable for cleaning steam generators in which the pipes are arranged in a pane arrangement and with both such and other steam generators of the U-type. type allows a relatively quick cleaning without risk of damaging the pipes.

For this purpose, the cleaning device comprises an elongated guide for the movable undercarriage which can be arranged with its longitudinal direction in the displacement direction of this undercarriage above the bottom between the two bundle parts of the pipe bundle, the undercarriage is movable over the guide, the spraying device contains a turntable mounted rotatably about a axis perpendicular to the longitudinal direction of the guide on this chassis, the nozzle holder is mounted rotatably about a axis oriented perpendicularly to the axis of rotation of the turntable on the turntable, the nozzle with its nozzle is in a plane directed perpendicular to the axis of rotation of the nozzle holder, and the sprayer comprises at least one rotary coupling between this rotary nozzle holder and the high pressure hose.

Naturally, the guide for the chassis is placed between the beam sections in the generator such that the axis of rotation of the turntable with respect to the chassis movable over the guide is directed substantially perpendicular to the bottom of the steam generator.

Naturally, the dimensions of the chassis and of the whole are formed by the turntable, the

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- mounted the nozzle holder, the nozzle and the rotating coupling sufficiently small that this chassis and all this could be brought through the access into the generator, while the dimensions of the latter whole 5 should also be sufficiently small that when the turntable rotates with respect to the chassis in the desired directions, this would not bump against the pipes at all.

In a special embodiment of the invention, the spraying device comprises two rotary couplings 10 between the nozzle holder and the high-pressure hose, the rotary axes of which are oriented transversely to each other, namely a first coupling coupling the rotating nozzle holder to the turntable and a second coupling connecting the high-pressure hose with connects the first coupling mounted on this rotatable turntable.

If the hose is relatively stiff, the spraying device can be moved with the aid of the hose, but preferably the cleaning device comprises means which drive the movable frame.

In an effective embodiment of the invention, the guide for the frame of the spraying device comprises a gutter in which the frame is partly movable.

The guide is advantageously adjustable in length so that it can be clamped in the jacket by adjusting.

The guide on one end expediently comprises a cylinder-piston mechanism.

In order to be able to provide the guide in the generator with a minimum of space around the steam generator, this guide can consist of several detachable parts.

In an effective embodiment of the invention, the sprayer includes means around the turntable

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o t ^ λ o n a - 6 - to block different positions on the chassis.

In a curious embodiment of the invention, the spray device includes a motor for driving the nozzle holder.

In another effective embodiment of the invention, the spray device comprises a plurality of nozzles spaced apart in axial sense of the nozzle holder.

Other details and advantages of the invention will become apparent from the following description of a steam generator cleaning apparatus according to the invention; this description is given by way of example only and does not limit the invention; the reference numbers relate to the accompanying drawings.

Figure 1 represents a schematically held horizontal cross-section of a steam generator during cleaning using a cleaning device according to the invention.

Figure 2 represents a vertical section of part of the steam generator of Figure 1.

Figure 3 represents part of the cross-section of Figure 2 but drawn to a larger scale.

Figure 4 is a side view of the sprayer and a portion of the guide from the cleaning device of the previous figures, drawn to a notably larger scale and with partial cut-away.

Figure 5 is a top view of the spraying device and the guide of Figure 4, diagrammatically showing some pipes of the pipe bundle.

In the different figures, like reference numerals refer to like elements.

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The cleaning device according to the figures has been proposed during the cleaning of a so-called U-type steam generator from a K.W.U. nuclear power plant.

This steam generator is known per se and is therefore only briefly described hereinafter to the extent necessary to make the invention clear.

This steam generator comprises a vertically mounted jacket 1 which is divided by a horizontal bottom 2 in an upper space 3 and a lower space divided by a vertical partition 4 in a supply compartment 5 and a discharge compartment 6.

In the upper space 3 an inner jacket 7 is mounted concentrically with the jacket 1, which extends to a distance from the bottom 2.

Within this inner sheath the tube bundle 8 extending in inverse U-shape is arranged. The pipes of the ascending bundle section open through the bottom 2 onto the supply compartment 5 while the pipes of the descending bundle section pass through the bottom 2 onto the discharge compartment 5.

Between the jacket 1 and the pipe bundle 8, the bottom 2 is provided with a groove 9 at the top.

Heating fluid from the nuclear reactor is supplied through the feed compartment 5 to the pipe bundle 8. This fluid flows through the pipe bundle 8 and is discharged through the discharge compartment 6.

Water fed into space 3 evaporates in contact with the tube bundle 8 and exits space 3 through a top mounted turbine.

Above the bottom 2, in the jacket 1, several access openings 10 distributed over its circumference are arranged, which are closed by lids 11 during the normal operation of the steam generator.

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These openings 10 open under the inner jacket 7 and at least one of these openings 10 opens on the elongated space 12 between the ascending bundle portion and the descending bundle portion of the pipe bundle 8.

The plane of symmetry of the tube bundle 8, which is indicated by the dashed line 13 in Figures 1 and 5, extends in the center of this space 12.

As can be seen from Figures 1 and 5, the pipes of the pipe bundle 8 are arranged according to a Chinese diamond arrangement, ie the pipes are located at the corners of a theoretical network with diamond meshes and the pipes form rows in three directions, namely, rows oriented perpendicular to the symmetry plane 13, rows which, viewed in an clockwise direction, make an angle of 15 -30 ° with this symmetry plane, 13 and rows which, viewed in an hour clockwise direction, make an angle of 150 ° with this symmetry plane. Each pipe is part of each of the series of rows. The spaces between the pipes are also oriented in these three directions and the three directions of the spaces 20 are indicated in Figs. 5 by arrows 14, 15 and 16 respectively.

The device according to the figures mainly comprises a guide 17, a spraying device 18 movable over the guide and a high-pressure lance 19 which is connected to the spraying device 18. The high-pressure lance is coupled in the usual manner to a high-pressure pump with which water is supplied to the spraying device 18 under a pressure of at least 200 bar and at a flow rate of at least 200 liters per minute.

The guide 17 comprises a metal tube 20 with a quadrilateral section and which is provided with a slit 21 along its entire length on one side and which, moreover, consists of several coupled but detachable pieces Γ * \ BAD 'ORIGINAL · -' - 9 - exists.

After all, the tube 20 cannot be fitted in one piece through an opening 10 issuing on the space 12 on the bottom 2, since sufficient space is not available next to the jacket 1. Thus, after removing the cover 11 on the intended opening 10, the pieces of the tube 20 are applied one by one with the slit 21 at the top. After this, the side opposite the slit 21 is considered the bottom side and the direction in which the pieces of the tube 20 are applied to the bottom 2 is considered the forward direction.

The first piece of tube 20 that is fitted is fitted with a buffer 22 on its front end and carries a wheel 23 on the bottom of its underside. 15 Before the first piece is completely lowered on the bottom, the following is coupled piece on.

The pieces of the tube 20 are provided with narrow ends for this coupling, with which they slide over each other and a spring-loaded ball 24 is mounted in the rear end of each piece, while a corresponding recess 25 is arranged in the front end of each piece of tube. When two consecutive pieces with their narrowed ends have been pushed over one another to the maximum, the ball 24 snaps into the hollow 25 as is clearly visible in figure 4.

The various pieces of pipe are thus coupled together, so that the already formed part of the guide 17 is thus rolled forward over the bottom 2.

The last part of the tube 20 is also provided with a wheel 23 on the underside, at the rear end. In addition, a cable 26 is attached to the rear end of this last-mentioned piece and is allowed to hang out through the opening 10 through BAD ORIGINAL :) 0 - 10 so that the tube 20 can then be lifted back from the bottom and through the opening 10 outside the generator. After the latter has been done, one can always pull a piece outside the generator and disconnect it from a subsequent piece until the complete tube 20 has been removed in this way.

A pneumatic cylinder piston mechanism 27 is also mounted in the rear end of the above-mentioned last part of the tube 20. This last piece 10 is fitted with this cylinder-piston mechanism 27 in the retracted position and the length of the tube 20 is then chosen so that it is almost equal to the inner diameter of the jacket 1. By extending the cylinder-piston mechanism 27, which by supplying compressed air through a compressed air line 28 connecting to this mechanism 27, the pipe 20 is clamped in the jacket 1, as is clearly visible in figure 3.

The spraying device 18 comprises a chassis 29 which is movable over the guide 17 and which is introduced into the generator together with the last piece 20 of the tube 20.

This chassis 29 contains four pairs of wheels 31 mounted in a chassis 30, which just fit into the tube 20 without being able to pass through the gap 21. With a sleeve-forming piece 32 secured to the chassis 30, the frame 29 extends through the slit 21.

The wheels 31 of the rear pair are laterally provided with a toothing 33 into which a gear wheel 34 mounted in the chassis 30 engages. This gear wheel 34 is mounted on a flexible shaft 35 which extends through the gap 21 and the opening 10 outside the generator.

The rest of the sprayer 18 after placing the tube 20 and the base 29 in the space 3 becomes BAD ORIGINAL? 6 - 11 - provided, of course, the dimensions of this remainder must be sufficiently small so that it can pass through the opening 10 which has only a diameter of 15 cm.

The tube 20 was arranged so that the slit 21 is at the top 5 and thus the tube 20 in fact forms an open gutter at the top. As a result, the geometric axis of the bush-forming piece 32 is also oriented perpendicular to the bottom 2 and thus vertically.

The latter rest of the sprayer 18 10 includes a turntable 36 which is pivotally rotatable about a vertical axis 45 and mounted in a variety of positions on the chassis 29 for blocking. The turntable has a tap 37 on the underside which is placed in the bush-forming part 32 of the chassis 29 and rests on a ball 38 mounted in the bottom of this bush. In the wall of the bush-forming piece 32 there is a ball 39 mounted on the one hand pushed into the cavity of the piece 32 by a spring 40 and on the other hand connected to a cable 41 which extends through the gap 21 and the opening 10 outside the generator. With the cable 41, the ball 39 can be pulled out of the cavity of the piece 32 against the spring 40. The pin 37 is provided on its outer side with several recesses 42 which can cooperate with the ball 39. When a recess 42 is opposite the ball 39, the latter is pushed through the spring 40 into the recess 42 and further rotation of the pin and thus of the turntable 36 is impossible as long as the ball 39 is not used with the cable 41 is drawn from the hollow 42. The different recesses 42 correspond to different positions of the turntable 36 relative to the chassis 29.

Balls 43 are mounted in the top of the piece 32, which also support the BAD ORIGINAL '5 - 12 - turntable 36 with the above mentioned ball 38.

The rotation of the turntable 36 relative to the chassis 29 is effected by means of a relatively stiff cable 44, which is attached to the turntable 36, eccentrically of the geometric axis of the spigot 37 and thus the rotation axis 45 of the turntable 36, and extends through the opening 10 beyond the steam generator.

A rotating nozzle holder 46 is mounted on the turntable 36, which carries four nozzles 47.

This nozzle holder 46 is rotatable about an axis 48 which is oriented perpendicular to the rotation axis 45 of the turntable 36. The four nozzles 47 are oriented radially with respect to this axis 48 with their nozzle opening.

The four nozzles 47 form two pairs with the nozzles 47 of each pair arranged diametrically opposite each other, the nozzles of one pair offset 90 ° from the nozzles 47 of the other pair and, in the longitudinal direction of viewed from the axis 48, the nozzles 47 of one pair are spaced from the nozzles 47 of the other pair corresponding to the center distance between the rows of pipes of the pipe bundle 8 oriented perpendicular to the plane of symmetry.

The nozzle holder 46 is alloyed with one end in a bearing 49 mounted in an upright portion of the turntable 36 and with its other end supported on a portion of the rotary coupling 50. The other portion of this coupling 50 is secured on the turntable 13.

Such rotary couplings are generally known and commercially available, in particular under the name "rotary seal". A suitable rotary coupling is commercially available under the designation "Barco".

This rotary coupling 50, with its longitudinal BAD ORIGINAL direction, is in line with the axis of rotation 45 and is thus arranged horizontally.

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The nozzle holder 46 is driven by an air motor 51 mounted on the turntable 36, the compressed air line 52 extending through the opening 10 outside the generator. A gear 53 is mounted on the shaft of the air motor 51, which meshes with a gear 54 mounted on the end of the nozzle holder 46 mounted in the bearing 49.

The rotary coupling 50 is mounted on the turntable 36 so that the exit of the portion fixedly mounted on this turntable 36 is vertically upward. This output communicates with a portion of a second identical rotary coupling 55.

15 The high-pressure hose 19 is clamped at the outlet of the other part.

The two rotary couplings 50 and 55 on the one hand allow a rotation of the nozzle holder 46 relative to the turntable 35, while on the other hand the high-pressure hose 20 19 does not have to rotate when the assembly, formed by the turntable 36, the nozzle holder 46, and the first rotary coupling 50 revolves about shaft 45 relative to chassis 29. The pressurized water supplied by the high-pressure hose 19 reaches the four nozzles 47 through the two couplings 25 50 and 55 and the nozzle holder 46.

With the aid of the flexible shaft 35 and the gear wheel 34, the chassis 29 and thus the complete spraying device 18 are moved intermittently over the guide 17, stopping each time when the nozzles 47 can spray between two adjacent rows of pipes. Thereby, the turntable 39 is successively placed in three positions whereby the nozzles * can successively spray into the spaces which are oriented according to the three aforementioned BAD ORIGINAL

Directions indicated by arrows 14, 15 and 16 in Figure 5. Thus, the turntable 36 is first positioned so that the longitudinal direction of the nozzle holder 46 is parallel to the plane of symmetry. Then turn the turntable 39 in one sense until the shaft 48 makes an angle of 60 ° with the plane of symmetry 13. After spraying in this position, turn the turntable 36 in the opposite sense first until the shaft 48 returns to its initial position. and further in the latter sense until the shaft 48 again makes an angle of 60 ° with the plane of symmetry 13. Obviously, the recesses 42 are located in the corresponding places so that in each of the aforementioned positions the turntable 36 would pass through the ball 39. blocked.

In order to check the operation of the spraying device 18 and, in particular, to know when the spraying device 18 must be stopped while moving over the guide 17, a miniature video camera 57 is arranged on the back of the turntable 36. This camera 57 is connected by lines 58 to a video screen not shown in the figures, which is arranged outside the steam generator.

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The total length of the sprayer 18 without the frame 29 must, of course, be such that for each of the positions of the turntable 36 described above relative to this frame 29, this sprayer does not come into contact with the pipes of the pipe bundle 8.

The high-pressure hose 19, which is relatively flexible, the compressed air line 28 for controlling the cylinder-piston mechanism 27, the compressed air line 52 for driving the motor 51, the flexible shaft 35 for driving the chassis 29, the cable 44 for the turning of the turntable 36, the cable 41 for decoupling the turntable 36 and the conduit 58 of the video camera 57 are guided just outside the opening 10 over a roller 59 which is alloyed in a BAD ORIGINAL

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* - ν - 15 - special annular flange 60 which is mounted on the above-mentioned opening 10 by means of bolts 61 instead of the cover.

The high pressure hose 19 then extends over a second roller 62 which is mounted in a support 63 which in turn is mounted on a raised bottom 64 which, as can be clearly seen from figure 2, surrounds the lower part of the steam generator. Hence, the high pressure hose 19 extends around a reel 66 driven by a compressed air motor 65 and mounted on the bottom 64. From this reel 66 the hose extends further to the above-mentioned high-pressure pump.

The compressed air lines 28 and 52, the flexible shaft 35, the line 58 and the cables 41 and 44 extend upwardly from the roller 59 to a control device 67 mounted on a higher bottom 68. However, these lines and cables can also extend over the driven reel 66.

The compressed air line 69 for driving the compressed air motor 65 also connects to the control device 67.

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Because of the risk of radiation, this control device 67 is preferably arranged as far as possible from the steam generator.

This control device 67 contains the above-mentioned video screen, a motor for driving the flexible shaft 35, the source of compressed air and the necessary controls for the motors, compressed air lines and cables.

30 The water sprayed by the spraying device 18 loosens the dirt from the bottom 2 and from the pipes of the pipe bundle 8. This dirt collects together with the water in the groove 9 in the bottom 2, from where it is used in the usual BAE0ORIGINAL? ; § - 16 - is pumped out through suction hoses 70. These suction rods 70 are fitted through an opening 10 other than that through which the high-pressure hose 19 was fitted and from which the cover 11 was removed. For the sake of clarity, the suction pumps are not shown in the figures. These pumps have an extraction capacity that is at least as great as the spray flow rate of the spraying device.

In the suction hoses, sight glasses are mounted by a second video camera, so that it can be determined when no more sludge is sucked through the suction hoses, and the spraying can be stopped in the determined position and at a specific location of the spraying device. With the above-described cleaning device, a very fast and efficient cleaning of the steam generator can be carried out. The accommodation of the operators of the establishment in the vicinity of the steam generator is kept to a minimum.

The invention is by no means limited to the above-described embodiment, and within the scope of the patent application many changes can be made to the described embodiment, including as regards the shape, the composition, the arrangement and the number of the parts used for the realizations of the invention are used.

In particular, the means for driving the various movable elements need not necessarily be of the type intended for this purpose.

For example, moving the chassis over the guide does not necessarily have to take place by means of a flexible shaft. This can also be done, for example, by means of a motor mounted on the chassis.

Turning the turntable does not necessarily have to be done by means of a cable.

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This can also be done by means of an engine or a cylinder-piston mechanism.

Rotating the rotating nozzle holder does not even necessarily require a separate motor. Due to the adapted design of the nozzles and / or the holder, the rotation of the nozzle holder can be caused by the high pressure water which is supplied to the device.

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Claims (22)

Device for cleaning a steam generator of the so-called U-type, which steam generator therefore contains an upright jacket (1), a pipe-5 bundle (8) with an ascending bundle section mounted therein, in the form of an inverted U and a descending bundle portion, a bottom (2) which closes at the bottom the openings between the pipes and between the pipes and the jacket (1), said jacket (1) above the bottom of at least one access (10) to the space ( 12) is provided between the two bundle-10 parts, the cleaning device comprising a spraying device (18) which itself has a movable base (29) which can be moved between the bundle parts over the bottom (2) and a nozzle holder (46). ) which carries at least one nozzle (17) and is movably mounted on this chassis (29), which cleaning device also contains a high-pressure hose (19) which connects to the spraying device (18) and through which liquid is pressurized n can be fed to the nozzle (47) outside the generator, characterized in that it comprises an elongated guide (17) for the movable undercarriage (29) which has its longitudinal direction in the displacement direction of this undercarriage (29) above the bottom (2) can be fitted between the two bundle portions of the pipe bundle (8), the base (29) is movable over the guide (17), the sprayer (18) includes a turntable (36) rotatable about a perpendicular shaft (45) oriented in the longitudinal direction of the guide (17) is mounted on this chassis (29), the nozzle holder (46) is rotatable about an axis (48) oriented perpendicular to the axis of rotation (45) of the turntable (36) is mounted on the turntable (36), the nozzle (17) is oriented with its nozzle in a plane rotatable (48) of the nozzle holder (46) and the sprayer (18) is oriented towards <·· —- ·. · '' + - 19 - contains at least one rotary coupling (50 or 55) between this rotary nozzle holder (45) and the high pressure hose (19). Device according to claim 1, characterized in that the spraying device (18) comprises two rotary couplings (50 and 55) between the nozzle holder (46) and the high-pressure hose (19), the rotary axes of which are oriented transversely to each other namely a first coupling (50) which couples the rotary nozzle holder (46) to the turntable (36) and a second coupling (55) connecting the high pressure hose 10 (19) to the first coupling (50) mounted on this rotatable turntable (36) ) connects. Device according to either of claims 1 and 2, characterized in that it comprises means (33-35) for driving the movable chassis (29). Device according to any one of claims 1 to 3, characterized in that the chassis (29) has a number of wheels (31) and is movable over the guide (17). Device according to claims 3 and 4, characterized in that the means (33-35) for driving the chassis 20 (29) comprise a flexible shaft (35) which can extend beyond the generator, a gear transmission ( 33,34) between this axle (35) and at least one of the wheels (31) of the chassis (29) and means for driving the flexible axle (35). Device according to any one of claims 1 to 5, characterized in that the guide (17) for the spraying device comprises a gutter (20) into which the undercarriage (29) partly protrudes. 7. Device according to claims 4 and 6, characterized in that the guide (17) is a tube (20) with an angular cross-section which is provided with a slit (21) in one side over almost its entire length, the wheels ( 31) roll from the mobile chassis (29) into this tube and project a portion (32) of this chassis (29) through the slit BAD ORIGINAL ^ 35 (21) and the rotatable turntable (36) '; 2 S 6, -20- carries. Device according to any one of claims 1 to 7, characterized in that the guide (17) is adjustable in length so that it can be clamped in the jacket (1) by adjustment. Device according to claim 8, characterized in that the guide (17) has a cylinder piston mechanism (27) at one end. Device according to any one of claims 1 to 10, characterized in that the guide (17) for the movable spraying device (18) consists of several detachable parts. Device according to any one of claims 1 to 10, characterized in that the spraying device (18) comprises means 15 (39-42) for blocking the turntable (36) in different positions on the base (29). Device according to claim 11, characterized in that the spraying device (18) comprises means (39-42) for locking the turntable (36) in at least three positions, namely a middle position, with the nozzles (47) their nozzle is oriented in a plane transverse to the plane of symmetry (13) between the ascending and descending portion of the pipe bundle (8) and two positions with the nozzles (47) with their nozzle 25 directed in clockwise faces given angles of 30 ° and 150 ° respectively with this plane of symmetry (13). Device according to one of claims 11 and 12, characterized in that the means (39-42) for blocking the turntable 30 (36) in different positions on the chassis (29) is remote from a cable (41 ) operable ratchet mechanism (39,40) mounted on one of the elements formed by the turntable (36) and the base (29) BADORIGINAL c -21- and recesses (42) co-operating with the ratchet (39) in the other element. Device according to any one of claims 1 to 13, characterized in that the turntable (36) is mounted releasably on the base (29). Device according to claims 14 and 15, characterized in that the base (29) is provided with a sleeve-forming piece (32), the turntable (36) is provided on its underside with a pin (37) provided in the opening of the sleeve (32) forming piece and the ratchet mechanism (39, 40) is mounted on the latter piece (32) while the recesses (42) are mounted in the stud (37). Device according to any one of claims 1 to 15, characterized in that the spray device (18) comprises a motor (51) for driving the nozzle holder (46). Device according to claim 16, characterized in that the motor (51) is a fluid motor mounted on the turntable (36) and driving the nozzle holder (46) through a gear transmission (53, 54). Device according to any one of claims 1 to 17, characterized in that the spray device (18) comprises at least two nozzles (47) which, viewed in the direction of the axis of rotation (48) of the nozzle holder (46), spaced so that the nozzles can reach at least two spaces between the rows simultaneously. Device according to claim 18, characterized in that the spray device (18) comprises two pairs of nozzles (47) mounted in the nozzle holder (46), the nozzles (47) of the one pair being spaced from the nozzles (47) BAD ORIGINAL / * -. ·. · ** "*: · / Ή. ! - 22 - other pair and the nozzles of one pair are diametrically opposite. Device according to any one of claims 1 to 19, characterized in that the nozzle (47) with its nozzle is directed radially with respect to the axis of rotation (48) of the nozzle holder (46). 21. Device according to any one of claims 1 to 20, characterized in that it contains a miniature video camera (57) mounted on the turntable (36) and connected to a video screen via a conduit (58). Device according to any one of claims 1 to 21, characterized in that it comprises a reel (66) disposed outside the generator and means (65,69) for driving this reel (66) and at least the high pressure hose ( 19) extends over this reel (66) during cleaning. BAD ORIGINAL «·· .; - '·. ·. J