Fastening Apparatus for a Cleaning Device Based on Introducing High-Amplitude Pressure Waves

Abstract

A fastening device for a cleaning device by introducing pressure waves through a hollow nozzle into a boiler to be cleaned through an opening in the boiler wall has a housing body, which can be fastened to the boiler wall with the aid of a fastening flange on the boiler side, the hollow nozzle being concentric with the opening in the boiler wall and orthogonal to the boiler axis. Damping units are arranged at regular angular intervals around the hollow nozzle in the longitudinal direction thereof and are each fastened with one free end to the boiler-side fastening flange and with the respective other free end to the housing body. When the pressure waves are triggered, the housing body is resiliently retained in the longitudinal direction away from the boiler and brought back into the initial position.

Claims

1. A fastening device for a cleaning device based on the introduction of high-amplitude pressure waves through a hollow cylindrical nozzle into a boiler to be cleaned through an opening in the boiler wall, wherein the fastening device comprises: fastening flange configured to fasten a housing body of the cleaning device to the boiler wall, a series of damping units, which are arranged at regular angular intervals around the hollow cylindrical nozzle of the cleaning device in the longitudinal axis thereof and are each fastened with one free end to the boiler fastening flange and with the respective other free end to the housing body, when the said high-amplitude pressure wave is triggered in the cleaning device, the housing body thereof is resiliently held back in the longitudinal direction away from the boiler and is brought back into the starting position by the damping units.

2. The fastening device according to claim 1, wherein the series of damping units is arranged in a concentric manner along the longitudinal direction of the hollow cylindrical nozzle of the cleaning device which is concentric to the opening in the boiler wall and is orthogonal to the boiler axis.

3. The fastening device according to claim 1, wherein the damping units comprise hydraulic dampers.

4. The fastening device according to claim 1, wherein each damping unit has two tension or compression springs arranged in series in their longitudinal direction, which are inserted between the boiler-side fastening flange and a centre plate or between the centre plate and the damping plate, wherein the housing body is rigidly fastened to the centre plate by first longitudinal rods, wherein the damping plate is rigidly fastened to the fastening flange by second longitudinal rods, and wherein additional hydraulic dampers are provided between the damping plate and the centre plate in the longitudinal direction around the hollow cylindrical nozzle.

5. The fastening device according to claim 5, wherein the two tension or compression springs of each damping unit arranged in a row in their longitudinal direction are arranged around one of the second longitudinal rods and are supported on the centre plate directly or on bushes facing the tension or compression springs on this centre plate, while the associated second longitudinal rod is supported through an opening in the centre plate, while the associated second longitudinal rod is passed through an opening in the centre plate.

6. The fastening device according to claim 1, wherein each damping unit has two groups of plurality of toroidal elastomers arranged in series in their longitudinal direction, which are interested between the boiler-side fastening flange and a centre plate or between the centre plate and the damping plate, wherein the housing body is rigidly fastened to the centre plate by first longitudinal rods, and wherein the damping plate is rigidly fastened to the fastening flange by second longitudinal rods.

7. The fastening device according to claim 9, wherein the closure housing has a guide tube in which the hollow cylindrical nozzle is freely guided.

8. The fastening device according to claim 10, wherein the guide tube is double-walled with an inner cavity which is provided helically from a feed point into the guide tube is pointing away from the boiler to the front edge of the guide tube, wherein the inner cavity can be supplied with a cooling fluid from a fluid source arranged outside the closure housing, and wherein the wall directed towards the boiler wall or the front edge of the guide tube have openings for an outlet of the cooling fluid.

9. The fastening device according to claim 11, wherein the guide tube is movable relative to the boiler wall flange in the longitudinal direction of the hollow cylindrical nozzle, and wherein the guide tube being at least partially retractable from the opening in the boiler wall in a rearward rest position.

10. The fastening device according to claim 9, wherein a closure flap is provided in the interior of the closure housing, which closure flap comprises two to four closure wings, which are each pivotable about a bearing axis arranged tangentially transversely to the longitudinal axis, in order to be opened by pivoting against the inner walls of the closure housing when the hollow cylindrical nozzle is advanced through the front edge of the closure housing.

11. The fastening device according to claim 13, wherein the closure wings are double-walled with an inner cavity, wherein the inner cavity can be supplied with a cooling fluid from a fluid source arranged outside the closure housing and the wall of the closure wings directed towards the boiler wall has openings for an outlet of the cooling fluid.

12. The fastening device according to claim 1, wherein the fastening device has a pivot axis arranged above the housing body, which is aligned transversely to the longitudinal axis of the hollow cylindrical nozzle, and on which the housing body is suspended via a pendulum arm.

13. The fastening device according to claim 15, wherein the pivot axis is fastened to a trolley which is displaceable in the longitudinal direction of this hollow cylindrical nozzle on a trolley profile provided above the hollow cylindrical nozzle.

14. The fastening device according to claim 1, wherein each damping unit has a pneumatically or hydraulically controllable damping cylinder and a piston which can be extended from the latter.

15. The fastening device according to claim 7, wherein the two groups of a plurality of toroidal elastomers of each damping unit arranged in a row in their longitudinal direction are arranged around one of the second longitudinal rods and are supported on the centre plate directly or on bushes facing the tension or compression springs on this centre plate, while the associated second longitudinal rod is supported through an opening in the centre plate, while the associated second longitudinal rod is passed through an opening in the centre plate.

16. The fastening device according to claim 1, wherein the fastening flange on the boiler side is part of a closure housing which has a boiler wall flange which can be fixed to the boiler at the longitudinal end opposite the fastening flange.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The terms FIG., FIGS., Figure, and Figures are used interchangeably in the specification to refer to the corresponding figures in the drawings.

[0024] Preferred embodiments of the invention are described below with reference to the drawings, which are for explanatory purposes only and are not to be construed restrictively. The drawings show:

[0025] FIG. 1 shows a schematic side view of a fastening device of a boiler cleaning device according to an embodiment of the invention with a cleaning tube with a larger diameter;

[0026] FIG. 2 shows a schematic side view of a fastening device of a boiler cleaning device according to a further embodiment of the invention;

[0027] FIG. 3 shows a perspective view of the boiler cleaning device according to FIG. 1;

[0028] FIG. 4 shows a side view of the boiler cleaning device according to FIG. 1;

[0029] FIG. 5 shows a schematic side view of a boiler cleaning device as shown in FIG. 2, but with a cleaning tube with a smaller diameter than the version shown in FIG. 1;

[0030] FIG. 6 shows a perspective view of the boiler cleaning device according to FIG. 5;

[0031] FIG. 7 shows a schematic, partially sectioned side view of a boiler cleaning device according to FIG. 2;

[0032] FIG. 8A shows a schematic, partially sectioned side view of the boiler cleaning device according to FIG. 2 in idle mode, i.e. in a parked position;

[0033] FIG. 8B shows a schematic, partially sectioned side view of the boiler cleaning device according to FIG. 8A in cleaning mode, i.e. in an advanced position;

[0034] FIG. 8C shows a schematic, partially sectioned side view of the boiler cleaning device according to FIG. 8A in a partially dismantled maintenance position, i.e. in a retracted position;

[0035] FIG. 9 shows a schematic perspective view of the 120-degree segment closure of the boiler cleaning device according to FIG. 7;

[0036] FIG. 10 shows a schematic, partially sectioned perspective view of the 120-degree segment fastener according to FIG. 9;

[0037] FIG. 11 shows a schematic, partially transparent perspective view of a segment of the 120-degree segment closure according to FIG. 10;

[0038] FIG. 12A shows a side view at the top, a top view of the 120-degree segment closure in the area of the closure housing on the left and a top view out of the boiler on the right, in each case of a closed 120-degree segment closure as in a rest or maintenance position;

[0039] FIG. 12B shows a side view at the top, a top view of the 120-degree segment closure in the area of the closure housing on the left and a top view out of the boiler on the right, in each case of a partially opened 120-degree segment closure at the transition between the parking and cleaning position;

[0040] FIG. 12C shows a side view at the top, a top view of the 120-degree segment closure in the area of the closure housing on the left and a top view out of the boiler on the right, in each case of an open 120-degree segment closure as in a cleaning position;

[0041] FIG. 13 shows a perspective side view of a ventilation device for the guide tube;

[0042] FIG. 14 shows a partially sectioned side view of the assembly group of a damping unit, as shown in FIG. 4 or FIG. 6;

[0043] FIG. 15 shows a schematic perspective view of a fastening device of a boiler cleaning device according to a further embodiment example with elastomers in the damping units;

[0044] FIG. 16 shows a side view of the boiler cleaning device as shown in FIG. 15; and

[0045] FIG. 17 shows a sectional partial side view of an assembly group of the elastomers with an optional guide tube around the longitudinal rod.

DESCRIPTION OF THE INVENTION

[0046] FIG. 1 shows a schematic side view of a boiler cleaning device according to an embodiment of the invention, comprising a shock wave generator 10 which is attached to a boiler 20 in a resilient manner. Resilient means that the shock wave generator 10 is not rigidly fixed to the boiler wall 20, but can move resiliently in the longitudinal direction of the shock wave to be generated. The shock wave generator 10 has a hollow cylinder 19 through which the pressure wave generated by this shock wave generator 10 is channelled into the boiler. This hollow cylinder 19 is inserted in a boiler connection piece 31. The boiler connection piece 31 is connected to a boiler wall flange 30, which is placed on the boiler wall 20 from the outside and is firmly connected to the boiler wall 20. The boiler access is defined through the boiler wall 20. The boiler connection piece 31 has a fastening flange 32 on the side opposite the boiler wall flange 30 in the longitudinal direction of the hollow cylinder 19. This boiler-side fastening flange 32 is thus directly and rigidly connected to the boiler wall flange 30 via the guide tube 31. A fastening flange 40 on the cleaning device side is rigidly connected to the boiler-side fastening flange 32, which holds the shock wave generator 10 via a series of here three second longitudinal rods or tension rods 154, around which damping spring assemblies 150, 156 are arranged. Each damping unit 150, 156 has two tension/compression springs 150, 156 arranged in a row in the longitudinal direction, which are inserted between the mounting flange on the boiler side and a centre plate 151 or between the centre plate 151 and the damping plate 152. The springs 150, 156 are supported on the centre plate 151 directly or on bushes 154 facing the ends of the springs on this centre plate 151, while the associated second longitudinal rod 154 is passed through an opening in the centre plate 151. Since the housing body 10 is now rigidly attached to the centre plate 151 with first longitudinal rods 155 and the damping plate 152 is rigidly attached to the boiler-side mounting flange with the second longitudinal rods 154, a cleaning plus leads to a compression and subsequent return of the hydraulic cylinders, which absorb the main part of the recoil forces, with the remainder being absorbed by the spring assemblies.

[0047] The three damping spring assemblies 150, 156 are arranged in the circumferential direction around the longitudinal axis of the hollow cylinder 19 at an angular distance of 120 degrees. Four or more, for example six or eight such packs can also be arranged, preferably at the same angular spacing. In addition to the damping spring packs 150, 156, hydraulic dampers 250 are provided between the centre plate 151 and the damping plate. The number of hydraulic dampers 250 can be one or two between each of the three damping spring packs 150, 156, i.e. a total of three or six. If there are four, six or eight damping spring assemblies 150, the same number of hydraulic dampers 250 can also be arranged at the same angular distance from one another, if possible. The hydraulic dampers 250 usually absorb between 50% and 90%, usually more than 75% to 90%, for example between 80% and 90% of the recoil energy. The advantage of the hydraulic dampers 250 also lies in the even distribution of the recoil forces over the stroke compared to the spiral springs of the spring assemblies 150, 156.

[0048] When the pressure wave shock of the shock wave generator 10 is directed in the longitudinal direction through the tube of the hollow cylinder 19 through the boiler wall 20 into the boiler, the hydraulic dampers 250 are lengthened or shortened by the recoil of the shock wave generator 10 due to the flow dynamics in the dampers and the damping springs 150, 156 are stretched or compressed in parallel and the shock wave generator 10 moves away from the boiler wall 20 in the longitudinal direction.

[0049] Advantageously, the weight of the shock wave generator 10 is supported by a holding lever 12 via a holding chain 11, which holding lever 12 is fastened via a horizontal swivelling axis 13 to a supporting frame 14, which is also fastened in a longitudinally displaceable manner in the longitudinal direction of the hollow cylinder 19 via a trolley 16 to a trolley profile 15. The holding chain 11 is provided with a length such that the axis of symmetry or longitudinal axis of the shock wave generator 10 corresponds to the axis of symmetry or longitudinal axis of the boiler nozzle 31 and the boiler wall flange 30, i.e. they coincide. In this way, the pressure wave is emitted around the same axis as the axis of the boiler outlet and the recoil is absorbed in an ideal manner.

[0050] The axis of the trolley profile 15 is advantageously arranged in the vertically aligned plane, which is also encompassed by the aforementioned longitudinal axis of the shock wave generator 10. This allows the shock wave generator unit with the hollow cylinder 19 to be pulled directly backwards out of the boiler nozzle 31.

[0051] FIG. 2 shows a schematic side view of a boiler cleaning device according to a further embodiment of the invention. As in the embodiment according to FIG. 1, the cleaning tube 19 has a larger diameter. The term larger diameter is to be seen in comparison with the embodiment according to FIG. 5.

[0052] Identical features are labelled with the same reference signs in all figures. The difference between the two devices shown in FIG. 1 and FIG. 2 lies in particular in the type of mounting and damping. While the design shown in FIG. 1 has a series of damping spring assemblies 150, 156 arranged around the circumference, three damping cylinders 50 are provided here at an angular distance of 120. These damping cylinders 50 have the same function as the hydraulic dampers. The only difference is that no spring assemblies are provided. In the design shown in FIG. 2, the combination of boiler-side mounting flange 32boiler connection piece 31boiler wall flange 30 of FIG. 1 is replaced by a closure housing 60, which has the same function. A further difference is that air connections 70 are provided at 120 intervals on the circumferential circle, which are explained in the further description and are in operative connection with the butterfly valve 80.

[0053] The inside of the shutter housing 60 has the 120 closures 81 of the shutter 80 described below.

[0054] The essentially triangular convex mounting flange 40 on the cleaning device side accommodates the abutments of the three damping cylinders 50 at its corners. The pistons 51 protruding from the damping cylinders 50 on the opposite side are attached to the shockwave generator 10, which is shown here only schematically as a simple cylinder. In other words, the weight of the shock wave generator 10 would act on the mounting flange 40 with a corresponding moment. It is also possible that the damping cylinders 50 are supported via a support plate, not shown in FIG. 2, with apertures provided for these damping cylinders 50 and a central hole for and on the connecting tube 43.

[0055] The hollow cylinder 19 is inserted in the connecting tube 43. Although it could also transmit the weight of the shock wave generator 10 with play and thereby tilting, it is preferably inserted freely in the tube 43. When an explosion is triggered by the shock wave generator 10 to clean the boiler, a shock wave travels through the hollow cylinder 19 in the longitudinal direction of the cleaning device, moving the shock wave generator 10 in a direction opposite to the boiler wall 20 via the recoil. The damping cylinders 50 have a damping effect on this movement and pull the shock wave generator back again after the first large amplitude. This can be achieved in particular by using active damping cylinders 50 as hydraulic cylinders, in which the pistons 51 can be extended and retracted in a correspondingly controlled manner.

[0056] A further advantage of the use of damping cylinders 50 over damping springs 150 will become apparent in connection with the description of FIGS. 8A to 8C.

[0057] FIG. 3 shows a perspective view of the boiler cleaning device according to FIG. 1. This also includes FIG. 4, which shows a side view of the boiler cleaning device according to FIG. 1. Three damping spring assemblies are braced in two sections by individual springs 150, 156 between a damping plate 152, a centre plate 151 and the fastening flange 40 on the cleaning device side. A series of flange connecting screws 41 are also recognisable on the fastening flange 40, with which this fastening flange 40 is fastened to the boiler-side fastening flange 32 or a corresponding flange of the closure housing 60. In other words, the closure housing 60 with an internal closure flap and/or ventilation can also be used with the construction according to FIG. 3, even if further advantages only arise in connection with a retractable generator 10 according to FIG. 2. The damping springs 150, 156 are guided through openings in the damping plate 152 and mounting flange 40 and braced on the outside in each case. Openings are provided in the centre plate 151 for the second tension rods 154 to pass through, each of which abuts against a sleeve 157 provided on both sides of the centre plate 151, which separates the spring action for the two sections to the damping plate 152 and mounting flange 40.

[0058] The hydraulic dampers 250 are arranged between the damping plate 152 and the centre plate 151, as they have to absorb the first recoil and the weaker springs should only return the then compressed hydraulic dampers.

[0059] From attachment points 153 on the shock wave generator 10, a series of here six first tension rods 155 are fixedly connected to the centre plate 151 at an angular distance of 60 degrees to each other, for example passed through the centre plate 151 with a reduced cross-section through a corresponding bore and fastened with a screw on an external thread located on each end of a first tension rod 155.

[0060] When the shock wave generator 10 is triggered, it moves away from the boiler wall 20 and exerts a tensile force on the centre plate 151 via the tension rods 155, which causes the right-hand damping springs 150 close to the mounting flange to stretch. At the same time, the left damping springs 156 on the damping plate side and the hydraulic dampers 250 are shortened so that a damping movement in the opposite direction results once the shock wave generator 10 has reached a maximum distance from the boiler wall 20. The damping springs 150, 156 and the hydraulic dampers 250 are designed in such a way that the oscillating movement is minimised.

[0061] The hydraulic dampers 250 are mounted on one side in the damping plate 152 and abut against the centre plate 151 by means of a piston and a spring (package 251) surrounding it.

[0062] Hydraulic dampers 250 are provided between damping plate 152 and centre plate 151 parallel to the springs 156, which reduce the peak force with the same energy absorption.

[0063] It can also be seen in FIG. 3 that the diameter of the hollow cylinder 19 is such that it is only guided through the inside diameters of the mounting flange 40, centre plate 151 and damping plate 152 with a small amount of play. It is therefore the maximum diameter of a hollow cylinder 19 that can be used together with this cleaning device.

[0064] FIG. 5 shows a schematic side view of a boiler cleaning device according to FIG. 2, but with a cleaning tube 190 with a smaller diameter, while FIG. 6 shows a perspective view of the boiler cleaning device according to FIG. 5. All the features of the attachment of the shock wave generator 10 to the attachment flange 40 according to FIG. 5 are identical to the features according to FIG. 3, the only difference being the different design of the exhaust pipe 190, which has a much smaller diameter here. Therefore, the distance from the outside of the hollow cylinder 190 to the inside diameter of the damping plate 152, the centre plate 151 and the flange 40 is much greater. Care is merely taken to ensure that an inner cover plate with a centrally adapted opening 42 is provided on the mounting flange 40 or on the corresponding closure housing 60, which surrounds the tube 190 with little play and can be easily sealed with a seal. In a preferred embodiment, the mounting flange 40 and the cover plate 42 are in one piece, in other words, the mounting flange 40 has an inner diameter corresponding to the cover plate 42 shown and is selected and installed according to the pipe diameter.

[0065] FIG. 14 shows a partially sectioned side view of the assembly group of a damping unit, as shown in FIG. 4 or FIG. 6. The hydraulic dampers 250 are shown fixed in the plate 152.

[0066] FIG. 7 shows a schematic partially sectioned side view of a boiler cleaning device according to FIG. 2. FIG. 8A shows the same schematic partially sectioned side view of the boiler cleaning device according to FIG. 2 in idle mode, i.e. in a parked position. FIG. 8A corresponds to a scaled-down version of FIG. 7. FIG. 8B shows a schematic partially sectioned side view of the boiler cleaning device according to FIG. 8A in cleaning mode, i.e. with the cleaning device in an advanced position. Due to the small damping path, it is essentially irrelevant whether FIG. 8B shows the cleaning device before, during or after a shock wave impact. FIG. 8C shows a schematic, partially sectioned side view of the boiler cleaning device according to FIG. 8A in a partially dismantled maintenance position, i.e. in a retracted position of the cleaning device. In addition, FIG. 9 shows a schematic perspective view of the closure flap 80 with the three 120-degree segment closures 81 of the boiler cleaning device according to FIG. 7.

[0067] The detailed view in FIG. 7 shows that a closed closure flap 80 is inserted in the interior of the closure housing 60, which tapers towards the boiler wall 20, on the inside of the fastening flange 40, which forms an inner shoulder of the closure housing 60. The closed closure flap 80 forms a convex cone projecting in the direction of the boiler wall 20. It consists of three 120-degree closures 81, each covering an angular range of 120 degrees, which can be swivelled about their swivel axes between the closed position shown in FIG. 7 and FIG. 9 and a fully open position shown in FIG. 12C. The 120-degree closures 81 are thereby pivotable about tangential axes lying in a plane at a predetermined distance from the longitudinal axis, the said plane being perpendicular to the longitudinal axis of the closure housing 60. These tangential axes are predetermined by the hollow bearing axes 84. Two sliding cylinders 82 are arranged around each hollow bearing axis 84 with a return spring 83 located between them, with which an opened segment of a 120-degree closure 81 is returned to the locking position.

[0068] In FIG. 8A, the shock wave generator 10 is in a rest position in which the usual working processes take place in the boiler. FIG. 8B then shows the forward movement of the shock wave generator 10 by shortening the pistons 51 in the damping cylinders 50, whereby the hollow cylinder 19 advances in the guide tube 31 in the direction of the boiler wall 20 and the front edges of the hollow cylinder 19 abut against the side surfaces of the 120-degree locks 81 and these open in synchronisation with each other against the spring force of the return spring 83. In FIG. 8B, the front edge of the hollow cylinder already protrudes slightly beyond the boiler wall 30 into the boiler.

[0069] The inner shape of the closure housing 60 extends from the shoulder on which the position axes 84 are provided for disciples and to the boiler wall flange 30 of the housing 60 so that the outward-facing sides and surfaces of the closure 81 can position themselves in this widened rear space when the shock wave races through the hollow cylinder 19, which is guided in the guide tube 31.

[0070] FIG. 8C then schematically shows a disassembled shock wave generator 10 in that the sealing housing 60 with the integrated sealing cap 80 is firmly attached to the boiler wall 20 via the boiler wall flange 30. The damping cylinders 50, on the other hand, are disassembled and shown individually, and the shock wave generator 10 with its attached hollow cylinder 19 is shown in further extension. Preferably, the shockwave generator 10 with the hollow cylinder 19 is suspended from the trolley profile 15 via the elements shown in FIG. 1: retaining chain 11, swivel arm 12, trolley 16. In addition to a single chain 11, it is also possible to provide further fastening chains or rods if the weight of the shockwave generator 10 with its hollow cylinder 19 is not balanced.

[0071] FIG. 9 shows a schematic perspective view of the 120-degree segment closure 80 of the boiler cleaning device according to FIG. 7 or also FIG. 8A. The closure elements 81, which are essentially triangular in a plan view, abut each other with connecting edges and end at a convex tip orientated towards the boiler wall 20. The surface pointing towards the boiler wall 20 and thus towards the boiler has a plurality of openings 85 for infusion cooling. In other words, each closure element 81 has a double-walled structure which extends as far as the sliding cylinder 82, so that each individual closure element 81 can be pressurised with cooling ambient air or corresponding gases via the air connection 70 and the hollow bearing axis 84. These pressurised gases flowing into the hollow bearing axis 84 then escape through the openings 85 into the space of the opening in the boiler wall 20.

[0072] In this context, FIG. 10 shows a schematic, partially sectioned perspective view of the 120-degree segment closure 81 according to FIG. 9. The reference sign 71 indicates the gas flow direction and thus a volume flow which enters the hollow bearing axis 84 at the air connection 70 and then enters the cavity in the double-walled closure elements 81 at the sliding cylinders 82, which are also hollow and have an opening to the hollow bearing axis 84, through corresponding openings in the wall of the hollow bearing axis 84 and then exits through the opening 85. In the embodiment example of the closure elements 81, reinforcing ribs 86 are provided.

[0073] FIG. 11 shows a schematic, partially transparent perspective view of a segment 81 of the 120-degree segment closure 80 according to FIG. 10, in which the regularly distributed openings 85 and the essentially radially extending reinforcing struts 86 are shown in particular. The passage for the volume flow 71 can be seen from the thickness of the transition between the sliding cylinder 82 and the closure element 81.

[0074] FIG. 12A shows above a side view, on the left a top view of the 120-degree segment closure in the area of the closure housing and on the right a top view out of the boiler, in each case of a closed 120-degree segment closure 80 as in a rest or maintenance position, i.e. in normal boiler operation. FIG. 12B shows at the top a side view, on the left a top view of the 120-degree segment closure 81 in the area of the closure housing 60 and on the right a top view out of the boiler, in each case of a partially opened 120-degree segment closure 81 during the transition between the parking and cleaning positions; and FIG. 12C shows above a side view, on the left a top view of the 120-degree segment closure 81 in the area of the closure housing 60 and on the right a top view out of the vessel, in each case of an open 120-degree segment closure 81 as when a cleaning position is reached, while cleaning is being carried out or shortly thereafter. The sequence of the drawings shows that the closure elements 81 open completely so that the hollow cylinder 19 can pass through them.

[0075] The individual closing elements 81 are pressed on by the front edge of the hollow cylinder 19 until the tip of the closing elements rests on the outside of the hollow cylinder 19 and this is pushed further into the boiler wall area if necessary.

[0076] FIG. 13 shows a perspective side view of a ventilation device for the guide tube 31. The mounting flange 32 is attached here to a modified closure housing 60, which is connected to the boiler wall flange 30, but can be moved longitudinally in relation to it. For this purpose, the sealing orifice 35 is located opposite the outer casing of the guide tube. For this purpose, an orifice flange 34 is mounted on the boiler wall flange 30, which has a receptacle on its side facing the boiler 20 in which an orifice 35 can be inserted. The orifice 35 surrounds the guide tube 38 and can be moved in height, in particular, so that the expansion of the boiler and thus a change in height of the breakthrough opening 22 in the boiler wall 20 can be tracked relative to the guide tube 38. This is associated with a mechanical decoupling of the recoil forces acting on the fastening flange 32, which normally act on the boiler wall 20, and which forces now act on a separately supported closure housing 60, whereby temperature or assembly-related misalignments with the guide tube 38 can be absorbed by the displaceable plate 35, which is mounted with play.

[0077] The guide tube 38 itself is double-walled and has a helical inner cavity 36. It can also be said that a helical intermediate wall is inserted between the two walls of the guide tube 38, which allows air to be blown in in the area of the mounting flange 32, via an air connection 70 not shown here, which then moves between the double walls of the guide tube 31 in the direction of the boiler, heating up, and finally flows into the boiler at the mouth of the opening in the boiler wall 20.

[0078] There is a cylindrical gap 37 between the boiler wall and the guide tube 38, which gap 37 is closed off from the shock wave generator 10 by the orifice 35. In the advanced position, the hollow cylinder 19 is always surrounded by the guide tube 38 and cooled by the air volume flow.

[0079] The guide tube 38 itself is designed with a flange 33 for this purpose, which is firmly connected to the mounting flange 32 of the housing 60 in the receptacle provided by the mounting flange 29. One or more passages may be provided in the receiving flange 29 for the cooling fluid, which can be fed into and via the flange 33 into the guide tube 38 at this point.

[0080] In an embodiment not shown in the drawings, a telescopic extension is provided for the retraction option of the guide tube 38, whereby the retraction mechanism can be pneumatic or hydraulic. By briefly advancing the guide tube 38 to the position shown in FIG. 13 and then retracting it after the cleaning pulse, the heating of the guide tube 38 is kept sufficiently low even at very high flue gas temperatures in the boiler and at the same time the often porous boiler wall 20 is protected from the cleaning pulse. Conversely, the guide tube 38 is at least partially withdrawn from the boiler wall opening 22 between individual cleaning pulses, so that essentially only the front edge 39 of the guide tube 38 is exposed to the gases contained in the boiler, since gas exchange with the interior of the guide tube does not usually take place.

[0081] FIG. 15 shows a schematic perspective view of a fastening device for a boiler cleaning device according to a further embodiment example with elastomers 350 in the damping units. FIG. 16 shows a side view of the boiler cleaning device as shown in FIG. 15. Finally, FIG. 17 shows a sectioned partial side view of an assembly group of the damping units constructed from elastomers 350 with an optional guide tube 353.

[0082] In a further advantageous embodiment of the damping units, these consist of toroidal or tyre-shaped elastomers 350 arranged in a row, each of which is arranged around one of the second longitudinal rods or tensioning rods 354 and is supported on the centre plate 151 directly or on bushes 352 (such as bushes 157) facing the directly adjacent elastomers 350 on this centre plate 151, while the associated second longitudinal rod 354 is passed through an opening in the centre plate 151. In particular, four such elastomers 350 are provided at an angular spacing of 90 degrees, each with two times seven elastomers 350 on the corresponding four longitudinal rods 354. Two first tension rods 155 are arranged between each of these four longitudinal rods 354 as in the other embodiments, i.e. between the centre plate 151 and the housing of the cleaning device with the damping plate 152. In particular, the elastomers 350 are copolyester elastomers. Spacers 351, in particular metal plates, can be provided between every two elastomers 350 and the second longitudinal rod 354 can be surrounded by a hollow radial guide tube 353, against which the inner edges of the elastomers 350 abut, so that the elastomers 350 have essentially no play with respect to the centre axis 355 of guide tube 353 and elastomers 350.

[0083] One advantage of using groups of elastomers 350 over hydraulic solutions is that the damping works satisfactorily in both directions. The drawing of the embodiment example shows a symmetrical arrangement of the same number of elastomers on both sides of the centre plate 151. It is also possible to use differently damping elastomers 350 based on a different material or different dimensions or to arrange a different number on both sides of the centre plate 151 in order to achieve asymmetrical damping.

LIST OF REFERENCE SYMBOLS

[0084] 10 shock wave generator [0085] 11 holding chain [0086] 12 holding lever [0087] 13 swivelling axis [0088] 14 support frame [0089] 15 trolley profile [0090] 16 trolley [0091] 19 hollow cylinder/exhaust pipe [0092] 20 boiler wall [0093] 22 boiler wall opening [0094] 29 aperture/mounting flange [0095] 30 boiler wall flange [0096] 31 boiler connecting piece/connecting pipe [0097] 32 boiler-side mounting flange [0098] 33 guide tube flange [0099] 34 aperture/mounting flange [0100] 35 aperture [0101] 36 helix-shaped interior slot [0102] 37 cylinder gap [0103] 38 guide tube [0104] 39 front edge [0105] 40 cleaning device-side mounting flange [0106] 41 flange connection screw [0107] 42 cover plate [0108] 43 connecting tube [0109] 44 gasket [0110] 50 damping cylinder/sliding cylinder [0111] 51 piston [0112] 60 closure housing [0113] 60 closure housing [0114] 70 air connection [0115] 71 gas flow direction [0116] 80 closing flap [0117] 81 120 degree closure [0118] 82 sliding cylinder [0119] 83 return spring [0120] 84 hollow bearing axle [0121] 85 effusion cooling openings [0122] 86 reinforcing ribs [0123] 150 damping spring [0124] 151 centre plate [0125] 152 damping plate [0126] 153 fixing point [0127] 154 second tension rod [0128] 155 first tension rod [0129] 156 damping spring [0130] 157 socket [0131] 190 hollow cylinder/exhaust pipe [0132] 250 hydraulic damper [0133] 251 hydraulic tappet [0134] 252 hydraulic damper spring [0135] 350 elastomer [0136] 351 spacer [0137] 352 socket [0138] 353 guide tube [0139] 354 second tension rod [0140] 355 centre axis