WO2003095742A1 - Steam bubble box unit - Google Patents

Abstract

The invention relates to a steam bubble box unit (10) comprising a steam bubble box (12) for applying steam to a passing material web (14), especially a paper web or a cardboard web, and an extension device (16) which is at least partially integrated into the steam bubble box, and enables said steam bubble box, which is located opposite the material web in an operating position, to be laterally i.e. generally transversally in relation to the moving direction (L) of the web, guided out of its operating position, and out of its lateral position back into said operating position.

Description

 Steam blow box unit

The invention relates to a steam blow box unit with a steam blow box for applying steam to a passing material web, in particular paper or cardboard web. It also relates to a method for moving a steam blower box out of its operating position.

Steam blow boxes are mainly used in papermaking. They are used in particular to raise the temperature of the material web with the help of the steam applied to the material web in order to improve the dewatering of the material web. A respective steam blower box offers the possibility of influencing the moisture cross profile of the material web by means of the sectional steam application transverse to the web running direction. Such a steam blow box is described for example in WO 99/41450.

Up to now, extension rails and an extension trolley have been used to expand the entire steam blower box. Such an expansion is now relatively time-consuming and involves a certain amount of additional parts. Such a method is particularly problematic in systems with a guide roller that cannot be lowered.

It has also already been proposed to extend only the internal internals of the steam blow boxes, including valves and zone chambers. In this case, since the housing with the steam outlet bores remains inside the paper machine, they are very difficult to access for cleaning.

The aim of the invention is to provide an improved steam blower box unit and an improved method of the type mentioned at the beginning which ensure quick removal, for example within an hour, and complete maintenance, in which cleaning of all areas on the steam blower box and quick replacement of defective parts is possible without any problems.

This object is achieved according to the invention by a steam blower box unit with a steam blower box for applying steam to a passing web of material, in particular paper or cardboard web, and with an extension device which is at least partially integrated in the steam blower box and via which the steam blower box opposite in an operating position of the web of material sideways, ie is generally transverse to the web running direction, can be moved out of its operating position and can be retracted into its operating position from its lateral position. The entire steam blower box can preferably be moved accordingly via the extension device.

Due to this design, the entire steam blow box can be expanded very quickly, which means that the advantages of the known or proposed units mentioned above are combined, but their disadvantages are avoided. Having preferred the whole

Steam box can be extended accordingly, the respective maintenance and / or cleaning work can then be carried out without any problems. Since no parts remain inside the paper machine, all areas are freely accessible. The number of wearing parts is reduced to a minimum.

In a preferred practical embodiment of the steam blower box unit according to the invention, the extension device comprises an extension aid which can be inserted into the steam blower box and through which the steam blower box is guided when it is being moved out or in. The extension aid advantageously has an elongated shape and, when in use, can in particular extend generally transversely to the direction of web travel.

If the steam blower box is arranged opposite a suction roll, for example, it can be extended at least substantially parallel to this suction roll. This has the advantage that a respective expansion is also possible during operation.

The extension aid can be used to extend and / or retract the steam blower box into the steam blower box and then remove it again. In principle, however, such an embodiment is also conceivable in which the extension aid remains inserted in the steam blower box even during operation. The last-mentioned embodiment brings i.a. the advantage of a reduced set-up time.

In a preferred practical embodiment of the steam blow box unit according to the invention, the extension aid can be used in a steam distribution space, in particular steam pipe, of the steam blow box which extends generally transversely to the web running direction.

In certain cases it can also be advantageous if the extension aid can be used in an additional expansion pipe of the steam blower box that extends generally transversely to the web running direction. Such an extension pipe can therefore also be provided in addition to an existing steam pipe.

The steam blower box is advantageously designed such that its upper part is available as a space for the extension aid. The extension aid can advantageously comprise an extension tube.

In an expedient embodiment, the extension tube and the relevant receptacle, i.e. the region of the steam blower box receiving the extension tube is of spherical design. It is also particularly advantageous if the steam blower box is provided on the driver side and the carrier side with a spherical support tube which is accommodated in a respective bearing, the running surfaces of the bearings preferably having a shape which is complementary to the spherical support tubes. The spherical shape of the driver tube and drive tube and the steam blow box have the advantage that even after the support tubes are rotated relative to the steam blow box around a common center, which means that the steam blow box is set correctly, e.g. appropriate centering is retained for a suction roll.

In a preferred alternative embodiment of the steam blower box unit according to the invention, the steam blower box comprises a support which extends generally transversely to the web running direction and is preferably T-shaped in cross section. In this case, an extension aid cooperating with this carrier for extending or retracting the steam blow box is provided.

Rollers or the like are advantageously provided between the extension aid and the wall of the steam distribution space or the carrier. For example, these can be ball rollers. For example, in the case of an extension tube, a plurality of rows of rollers distributed over the tube circumference and each extending in the longitudinal direction of the tube can be provided. The extension aid can preferably be used in an upper area of the steam blower box. The zonal steam guide is expediently arranged in such a way that the upper region of the steam blower box can be used simultaneously as a steam room and an extension system.

The steam blower box is preferably extendable towards the driver's side. It is particularly advantageous if the extension aid can be axially fixed, particularly on the upper part of a drive-side bearing.

The axially fixed extension aid can at the same time be secured against rotation about its longitudinal axis.

It is particularly advantageous if the axially fixed extension aid can simultaneously be pivoted about a preferably horizontal axis perpendicular to its longitudinal axis. The risk of tilting and / or bending of the entire steam blower box / extension aid system is thus reduced to a minimum.

The steam blower box is preferably provided with a connection on the driver's side, to which a crane, a cable winch and / or the like can advantageously be connected.

The extension device can in particular also comprise a pull-out rope, a deflection rope guided in particular via deflection rollers attached to the extension aid and / or a pull-in rope.

According to a further expedient embodiment of the steam blow box unit according to the invention, the steam blow box can be extended or retracted via a rack and pinion gear. For example, a toothed rack can be provided on the underside of the steam blow box and / or, for example, on the underside of a support tube assigned to the steam blow box on the driver's side, with which a drivable pinion can be brought into engagement.

For maintenance purposes, removable steam outlet plates can also be provided, for example. However, these are not mandatory.

In addition, such a storage is conceivable, for example, that the steam blower box only has to be raised by a few millimeters, approximately 10 mm, in order to enable rapid removal. For this purpose, the simplest possible adjustment is expediently provided.

In a further advantageous embodiment of the steam blower box unit according to the invention, the extension tube also serves to supply steam. The extension tube preferably remains inserted in the steam blower box during operation.

The extension tube can expediently be inserted into a support tube of the steam blow box which extends generally transversely to the web running direction. The area between the extension tube and the support tube is preferably sealed by an inflatable ring seal. No more flange connections have to be loosened.

The steam can be supplied, for example, from a steam connection into the extension tube, through holes in the extension tube in the area between the extension tube and the support tube, through holes in the support tube into a steam distribution space and via zone regulating valves in the corresponding zone chambers. In a further preferred practical embodiment of the steam blower box unit according to the invention, the steam blower box is provided on the driver's side and / or drive side with a supporting element, which in operation rests on a driver's side or drive side slide rail. The slide rail can in particular be assigned to a driver-side or drive-side mounting, wherein it is preferably firmly connected to the driver-side or drive-side mounting.

The steam blower box can be adjustable on the slide rails, for example, between an operating position closer to the passing material web and a maintenance position further away from this material web. The steam blower box can thus be moved closer to a suction roller, for example, or further away from it via these slide rails.

In order to adjust the steam blower box between the operating position and the maintenance position, an adjusting device comprising at least one cylinder / piston unit can be provided at least on the driver's side. Such a control device on the driver's side can expediently be connected to the driver's support element.

At least one frame-like slide rail is advantageously provided.

The support elements can each be designed, for example, as a support tube.

In a preferred practical embodiment, a lifting frame provided with at least one roller is provided on the driver's side and can be raised in such a way that the roller with the driver-side support element comes into contact and lifts the driver-side support element from the driver-side slide rail. In this case, the lifting frame on the driver's side can expediently be raised by means of an adjusting device comprising in particular at least one cylinder / piston unit. The operator-side lifting frame is expediently adjustable relative to the operator-side mounting.

In an expedient practical embodiment, guide elements which are firmly connected to the driver-side lifting frame are guided in cross-section, in particular U-shaped guides. These can in particular be firmly connected to the storage on the driver's side.

The driver-side support element expediently rolls off the operating or maintenance position when the steam blow box is moved out laterally, generally transversely to the web running direction, and when it is retracted on the roller assigned to the driver-side lifting frame.

At least two rollers are preferably assigned to the driver's lifting frame.

The storage on the driver's side can, for example, be provided with an upper part, which can be dismantled in particular for the lateral removal of the steam blow box.

In particular for the lateral removal of the steam blower box, the connection between the steam blower box or the driver-side support element and the driver-side actuating device can also be released. For adjusting the steam blower box between the operating position and the maintenance position, an adjusting device comprising at least one cylinder / piston unit is expediently provided at least on the drive side. This drive-side actuating device can expediently be connected to the drive-side support element.

A lifting frame is preferably provided on the drive side, which can be raised in such a way that the drive-side support element connected to it lifts off the drive-side slide rail. When the trieseeit lifting frame is lifted, the drive-side end of the extension aid provided with castors is at the same time raised, at least one upper roller of the extension aid coming into contact with the inner wall of the steam distribution space or the additional extension pipe. When the drive-side lifting frame is raised, the entire drive-side end of the steam blow box is preferably also raised.

In a preferred practical embodiment of the steam blower box unit according to the invention, with the lifting of the drive-side lifting frame, a locking bolt which passes through the drive-side end of the extension aid and is guided in elongated holes in the drive-side bearing is acted upon or carried and the drive-side end of the extension aid is also lifted by means of this locking bolt.

The drive-side lifting frame can expediently be raised by means of an adjusting device comprising at least one cylinder / piston unit.

The drive-side lifting frame is expediently adjustable relative to the drive-side mounting. The connection between the steam blow box or the drive-side support element and the drive-side actuating device is expediently detachable, in particular for the lateral removal of the steam blow box.

According to the invention, the above-mentioned object is also achieved by the method specified in claim 56. Advantageous refinements of the method according to the invention are specified in the subclaims.

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the drawing; in this show:

Figure 1 is a schematic cross-sectional view of a

Steam blower box unit consisting of a steam blower box and an extension device which is at least partially integrated in the steam blower box, an extension tube being provided as an extension aid, which can be inserted into a steam tube of the steam blower box,

Figure 2 is a schematic cross-sectional view of others

Embodiments of the steam blower box unit, an extension tube, for example, can again be provided as an extension aid, but here it can be inserted into an expansion tube of the steam blower box provided in addition to the steam tube, or an extension aid can be used, for example, which has a T-shaped carrier, for example interacts in the steam box, FIG. 3 shows a schematic representation of the end of a further embodiment of the steam blower box unit on the driver's side,

FIG. 4 shows a schematic end view of the driver-side end of the steam blower box unit according to FIG. 3,

FIG. 5 shows a schematic side view of the drive end of the steam blower box unit according to FIG. 3,

FIG. 6 shows a schematic end view of the drive end of the steam blower box unit according to FIGS. 3 to 5,

FIG. 7 shows a schematic partial illustration of a further embodiment of the steam blower box unit with a

Rack gear,

FIG. 8 shows a sectioned partial illustration of the steam blower box unit according to FIG. 7, sectioned along the line A-A,

FIG. 9 shows a schematic cross-sectional illustration of a further embodiment of the steam blower box unit, in which the extension tube also serves to supply the steam,

Figure 10 is a schematic side view of the driver's side

End of the steam blower box unit according to FIG. 9, FIG. 11 shows a schematic end view of the driver-side end of the steam blower box unit according to FIG. 9,

FIG. 12 shows a schematic, partially sectioned side view of the drive end of the steam blower box unit according to FIG. 9,

FIG. 13 shows a schematic cross-sectional representation of the drive end of the steam blower box unit according to FIG. 9, cut along the line A-A of FIG. 12,

Figure 14 is an enlarged cross-sectional view of the in the

FIG. 12 recognizable inflatable ring seal, cut along the line B-B in FIG. 13,

Figure 15 is a schematic side view of the driver's side

End of a further embodiment of the steam blow box unit,

FIG. 16 shows a schematic end view of the driver-side end of the steam blower box unit according to FIG. 15,

FIG. 17 shows an enlarged side view of the driver-side mounting of the steam blower box unit according to FIG. 15,

FIG. 18 shows an enlarged end view of the driver-side mounting of the steam blower box unit according to FIG. 15,

FIG. 19 shows an enlarged top view of the driver-side mounting of the steam blow box unit according to FIG. 15, Figure 20 is a schematic side view of the drive end of the steam box unit according to Figure 15 and

FIG. 21 shows a schematic side view of the drive end of the steam blower box unit according to FIG. 15.

1 shows a schematic cross-sectional illustration of a steam blow box unit 10 with a steam blow box 12 for applying steam to a passing material web 14 and with an extension device 16 at least partially integrated in the steam blow box 12.

The material web 14 can in particular be a paper or cardboard web. In the present case the material web 14 is e.g. with at least one felt (not shown) over a suction roll 18, opposite which the steam blower box 12 is arranged during operation.

The extension device 16 comprises an extension tube 20 serving as an extension aid, which can be inserted into a steam tube 22 of the steam blow box 12.

Via this extension device 16, which includes the extension tube 20 and the steam tube 22, the steam blow box 12, which is opposite in an operating position of the suction roller 18 and thus the material web 14, can be moved out of its operating position laterally, ie generally transversely to the web running direction L and parallel to the suction roller 18, and accordingly from one relevant lateral position retractable into this operating position. The entire steam blower box 12 can be moved accordingly via the extension device 16. As can be seen from FIG. 1, rollers 24, for example ball rollers, are provided between the extension tube 20 and the inner wall of the steam tube 22.

In the inserted state, the extension tube 20 extends generally transversely to the web running direction L and parallel to the suction roller 18.

The extension tube 20 can be used to extend and / or retract the steam blow box 12, for example, in the steam blow box 12 and then removed again. However, it is also possible for the extension tube 20 to remain inserted in the steam blow box 12 even during operation.

In the present case, therefore, a general effect across the board

The steam pipe 22 forming the steam direction 22 extending the web running direction L and the extension pipe 20 together in such a way that when the steam blower box 12 is extended or retracted, it is guided through the extension pipe 20 accordingly.

The steam blower box 12 comprises a plurality of zone chambers 26 lined up along the web width, which can be delimited towards the suction roller 18, for example by removable steam outlet plates 28.

The steam from the steam pipe 22 enters a further steam distribution space 106 through a plurality of bores 104 which are arranged across the width and is assigned to the zone chambers 26 there via the control valves 30. FIG. 1 also shows a pneumatic control valve 30, for example, via which a respective zone chamber 26 can be supplied with steam accordingly.

The steam blower box 12 can also be provided with drainage devices 32.

In FIG. 1, insulation 34 on the driver's side and a blind flange 36 of the steam blower box 12 on the driver's side can also be seen.

The steam pipe 22 thus simultaneously fulfills a steam distribution function and a supporting or static function.

FIG. 2 shows a schematic cross-sectional illustration of further embodiments of the steam blow box unit 10.

Then the extension aid, for example again formed by an extension tube 20 (see also FIG. 1), e.g. can also be used in an expansion pipe 38 of the steam blow box 12 which extends generally transversely to the web running direction L and is provided in addition to the steam pipe 22.

According to an alternative embodiment which is also indicated in FIG. 2, the steam blower box 12 can also comprise, for example, a carrier 40 which extends generally transversely to the web running direction L and is preferably T-shaped in cross section. In this case, an extension aid 20 'which cooperates with the carrier 40 to extend or retract the steam blow box 12 is provided. This can comprise, for example, two bars or the like extending in the transverse direction, on which the carrier 40 is again supported, for example, by rollers 24. In the present case, too, a plurality of zone chambers 26 which follow one another in the transverse direction are again provided. The zone chambers 26 are connected to the steam pipe 22 via valves 42.

The extension tube 20 and the relevant receptacle of the steam blow box 12, i.e. For example, the steam pipe 22 (cf. FIG. 1) or the additional expansion pipe 38 (cf. FIG. 2) can, for example, also be spherical, which results in a corresponding centering.

As can be seen from FIGS. 1 and 2, the extension aid 20, 20 ′ can be used in particular in an upper region of the steam blow box 12. Accordingly, the steam pipe 22 (cf. FIG. 1) or the additional extension pipe 38 (cf. FIG. 2) can be arranged in an upper region of the steam blow box 12, while the zone chambers 26 are provided in a lower region.

As can also be seen in particular from FIGS. 3 to 6, the steam blower box 12 can be moved out in the direction of the driver's side (FS) in particular.

FIGS. 3 to 6 show a schematic partial illustration of an embodiment of the steam blower box unit 10, in which the extension aid, like the embodiment in FIG. 1, is again formed by an extension tube 20 which can be inserted into a steam tube 22.

In the present embodiment, the extension tube 20 serving as an extension aid is e.g. B. axially fixable on the upper part 44 of a drive-side bearing 46. At the same time, the axially fixed extension tube 20 can be secured against rotation about its longitudinal axis. This is done by a Bolt 48 reached, whereby the extension tube 20 is also pivotable about a vertical to its longitudinal axis, here horizontal axis.

In addition, the steam blow box 12 can be provided with a connection 50 on the driver's side, to which, for example, a crane, a cable winch 52 and / or the like can be connected.

As can be seen from FIGS. 3 to 6, the extension device 16 can also comprise, for example, a pull-out rope 54, a deflection rope 60 guided over deflection rollers 56, 58 fastened to the extension tube 20 and a pull-in rope 62.

The steam blower box 12 is provided on the driver side and on the carrier side with a spherical support tube 64 and 66, respectively, which is received in the driver-side bearing 68 and in the drive-side bearing 46.

The bearings 46, 68 can be provided with slide rails 70 (e.g. MS, Teflon, etc.), with mutually opposite slide planes 72 (see in particular FIG. 6).

For example, by means of hydraulic or lifting cylinders 74 (see, for example, FIGS. 4 and 6), the steam blow box 12 can be positioned in the desired manner, for example, relative to the suction roll 18 (see. FIG. 1).

The running surfaces of the drive-side and driver-side bearings 46, 68 have a shape that is complementary to the spherical support tubes 64, 66.

The convex shape of the driver tube and drive tube 64 and 66 and the steam blow box 12 have the advantage that even after turning the support tubes 64, 66 relative to the steam blow boxes 12 around a common center 108 (see FIG. 6), which may be necessary for the correct setting of the steam blow box 12 relative to the suction roller 18, a corresponding centering is retained.

In the lower right part of FIG. 5, part of the steam supply 102 is again shown in an enlarged view.

An example of an expansion of the steam blower box 12 is described below, for example with reference to FIGS. 3 to 6.

Here are z. B. Take the following prepared measures:

Disassembly of the drive-side steam connection 73 - disassembly of the driver-side blind flange 36

Retracting the extension tube 20, which preferably remains permanently in the steam tube 22 serving to distribute the steam. Fixing (securing against twisting) of the extension tube 20 to the upper part 44 of the drive-side bearing 46 by means of a bolt 48 - disassembly of the driver-side upper bearing part 76

Disassembly of the driver's hydraulic or lifting cylinder 74 from the support tube 64 (see FIG. 4)

Disassembly of the drive-side hydraulic or lifting cylinder 74 from the support tube 66 (see FIG. 6) - lifting of the steam blower box 12 on the driver's side by means of

Adjustment screws 78 until the driver-side support tube 64 rests on the ball rollers 80 (see the left part of FIG. 3). Loosen the fastening screws 82 of the drive-side upper bearing part 44 (see FIG. 6). Lifting the entire upper bearing part 44 on the drive side (cf. FIG. 6) by means of adjusting screws 78, 78 ', so far that first the upper bearing part 44 is exposed and then the steam blow box 12 including the drive-side support tube 66 is slightly raised.

The steam blower box 12 can now be extended, for example, by means of an indoor crane, for which the following steps have to be carried out:

Attaching the hall crane to the connecting flange 84 on the driver's side - provision of a support bracket 86 for storing the driver's side

Part of the steam box 12 preferably after about a third of the extension distance.

Pulling out the steam blower box 12 means that it is raised at the driver's attachment point as a result of the train. However, since the extension tube 20 is now rotatably mounted on the drive-side attachment point by means of the attachment bolt 48 (cf. in particular FIG. 6), the risk of tilting and / or bending of the entire system comprising the steam blower box 12 and the extension tube 20 is reduced to a minimum or locked out.

The steam blower box 12 can, however, also be used without an indoor crane, e.g. be extended by means of a winch 52.

For this purpose, the steam blower box unit 10 comprises, in particular, a pull-out rope 54, deflection rollers 56, 58 fastened to the extendable pipe 20, a deflecting rope 60 fastened within the extendable pipe 20 and a pull-in rope 62. By winding the pull-out rope 54 by means of the winch 52, the steam blower box 12 can then be extended accordingly. The following steps are conceivable for such an extension:

- Setting up the winch 52

Fasten the pull-out rope 54 to the flange connection 88 on the driver's side

Connect the pull-in rope 62 to the upper section

60a of the deflecting rope 60, in particular for a later retraction

Attaching the lower section 60b of the deflecting cable 60 to the connecting flange 88 on the driver's side

Provision of the support bracket 86 for storing the driver's side

Part of the steam blower box 12 preferably after about a third of the extension distance

Extension of the steam blower box 12 by means of the cable winch 52

The steam blow box 12 can be retracted by winding the pull-in rope 62.

After the steam blow box 12 has been drawn in, the deflecting rope 60 consisting of the sections or partial lengths 60a, 60b remains within the extension tube 20.

The final installation position is achieved by an end stop 90 on the drive-side bearing 46.

Instead of using an indoor crane or a cable winch, the steam blower box 12 can also be extended or retracted, for example, via a rack and pinion gear 92 (see FIGS. 7 and 8). A corresponding Appropriate retraction and extension is possible while the paper machine is in operation.

The underside of the steam blow box 12 and the underside of the driver-side support tube 64 are preferably provided with a toothed rack 94.

The steam blower box 12 is extended by means of the rack and pinion gear 92 on the driver's bearing 68. For this purpose, a drivable pinion 96 is brought into engagement with the rack 94. The drive 98 can be seen in particular in FIG.

The following steps in particular can be provided for such an extension of the steam blower box:

- Raise the rack and pinion gear 92 by means of adjusting screws

78 on the driver-side bearing lower part 100 until the pinion 96 engages in the rack 94

Provision of the support bracket 86 (cf. also FIG. 3) for depositing the part of the steam blow box 12 on the driver's side, preferably after about a third of the extension distance

Start release for the rack and pinion gear 92 for extending the steam blow box 12.

FIG. 9 shows a schematic cross-sectional illustration of a further embodiment of the steam blower box unit 10, in which the extension tube 20 also serves to supply the steam.

In this case, the extension tube 20 preferably remains inserted in the steam blow box 12 during operation. As can be seen from FIG. 9, the extension tube 20 is inserted into a support tube 22 ′ of the steam blow box 12 that extends generally transversely to the web running direction L.

As can also be seen in particular from FIGS. 10 to 14, the area W between the extension tube 20 and the support tube 22 ′ is preferably sealed by an inflatable ring seal 110.

Since the steam connection 102 no longer has to be dismantled on the drive side, it can be removed more quickly. A possible procedure for such an expansion is described in more detail below.

The extension tube 20 can remain permanently installed.

The area W between the extension tube 20 and the support tube 22 ′ is, as already mentioned, preferably sealed by an inflatable ring seal 110. Flange connections therefore no longer have to be released.

In principle, however, a flange connection is also possible.

In the present embodiment shown in FIGS. 9 to 14, for example, there is a steam path from the steam connection 102 into the extension tube 20, through bores 112 in the extension tube 20 into the region W (cf. in particular FIG. 9), through bores 114 in the support tube 22 '. into the steam distribution space 106 and via the control valves or zone regulating valves 30 into the corresponding zone chambers 26. The extension tube 20 and the support tube 22 'are connected to one another by the inflatable ring seal 110, or alternatively, for example, by a flange.

In order to ensure tightness, the two contact surfaces 116, 118 on the support tube 22 'and on the extension tube 20 must not move when the ring seal 110 is inflated. This can be ensured, for example, as follows:

The extension tube 20 is guided by means of a flat steel 120, which is fastened to the underside of the locking bolt 48 ′, in a groove 124 within the upper bearing part 44 on the drive side.

The drive-side bearing-support tube 66, ^'which with the steam blower 12, and thus the support tube 25' is fixedly connected, is guided by means of locking pin 122 in a groove 126 in the region of the drive-side bearing-support tube 66th

The movements of the locking pin 122 relative to the bearing support tube 66 and of the extension tube 20 relative to the drive-side upper bearing part 44 are not impaired when the steam blower box 12 is pivoted on and off.

The removal of the steam blower box 12 can include the following steps, for example:

Work on the driver side as already described Work on the drive side:

- Close the compressed air supply for the ring seal 110 - Turn the locking bolt 122 by 90 ° - Loosen the fastening screws 82

- Lifting the drive-side upper bearing part 44 by means of the adjusting screws 78

(Drive-side bearing support tube 66 is exposed) The extension tube 20 remains fixed in its position, but is still movably mounted via the locking bolt 122. Expansion as already described

The installation of the steam blower box can include the following steps, for example:

Retracting the steam blow box 12 as already described Retracting the steam blow box 12 until the contact surface 116 of the support tube 22 ′ abuts the ring flange or the contact surface 118 of the extension tube 20.

The required work area 128 is thus precisely defined.

Work on the driver's side as described

Working on the drive side:

Lower the steam blower box 12 via the adjustment screws 78 to the ones fastened to the drive-side bearing 46

Stops 90

Fixing the position by means of the fastening screws 82 Locking the steam blower box 12 by means of the locking pin 122 - securing the locking pin 122 against sliding out

Open the compressed air supply for the inflatable ring seal 110

Otherwise, this embodiment can at least essentially in particular have the same structure as that described above Have embodiments. Corresponding parts are assigned the same reference numerals.

FIGS. 15 to 21 show a schematic representation of a further embodiment of the steam blower box unit 10, in which the steam blower box 12 is provided on the driver side and on the drive side with a support element 64 or 66, which in operation is mounted on a guide rail or drive side slide rail 130 or 132 rests.

The driver's side is shown in FIGS. 15 to 19. FIG. 15 shows the driver-side end of the steam blower box unit 10 in a schematic side view, while this driver-side end is shown in a schematic front view in FIG. 16. The driver-side mounting of this further embodiment of the steam blow box unit is shown in FIG. 17 in an enlarged side view, in FIG. 18 in an enlarged end view and in FIG. 19 in an enlarged top view.

Figures 20 and 21 show the drive side. The drive end of the steam blower box unit 10 is shown in a schematic side view in FIG. 20 and in a schematic front view in FIG. 21.

As can be seen from these FIGS. 15 to 21, the respective slide rail 130, 132 is assigned to the driver-side or drive-side mounting 68 or 46. The respective slide rail 130, 132 can in each case be firmly connected to the driver-side or drive-side mounting 68 or 46. The steam blower box 12 is adjustable on the slide rails 130, 132, for example, between an operating position closer to the passing material web 14 and a maintenance position further away from the latter.

To adjust the steam blower box 12 between the operating position and the maintenance position, an actuating device 134 (cf. in particular FIG. 16) or 146 (cf. in particular FIG. 21) comprising in particular at least one cylinder / piston unit is provided on the driver and drive side. In the present exemplary embodiment, these actuating devices 134, 146 each comprise at least one hydraulic cylinder.

As can be seen in particular again with reference to FIGS. 16 and 21, the driver-side actuating device 134 can be connected in particular to the driver-side support element 64 and the drive-side actuating device 146 in particular to the drive-side support element 66. As will be described in more detail below, a releasable connection between the actuating device and the support element is provided in each case.

As can be seen, for example, from FIG. 19, the slide rail 130 can in particular be designed like a frame.

The support elements 64, 66 can be at least essentially flat at least on the side facing the respective slide rail 130, 132 (cf. for example FIGS. 16 and 21). In principle, these support elements 64, 66 can, for example, again be provided as support tubes. As can be seen from FIGS. 15 to 19, a lifting frame 138 provided with rollers 136 is provided on the driver's side. In the present case, the lifting frame 138 is provided with two rollers 136, for example.

This driver-side lifting frame 138 can be raised such that the rollers 136 come into contact with the driver-side support element 64 and the driver-side support element 64 lifts off the driver-side slide rail 130. This lifting frame 138 on the driver's side can be raised by means of an adjusting device which, in the present exemplary embodiment, comprises two cylinder / piston units or lifting cylinders 140.

The driver-side lifting frame 138 can therefore be adjusted in particular relative to the driver-side bearing 68 via the cylinder / piston units 140. In this case, guide elements 142 which are fixedly connected to the lifting frame 138 on the driver's side can be guided in guides 144, in particular U-shaped in cross section (cf. in particular FIGS. 16 to 19). The guides 144 can in particular be firmly connected to the driver-side bearing 68.

When the steam blower box 12 is moved laterally out of its operating or maintenance position, as well as when it is retracted, generally transversely to the web running direction L, the driver-side support element 64 can therefore roll on the rollers 136 assigned to the driver-side lifting frame 138.

As can be seen, for example, from FIG. 16, the driver-side bearing 68 has an upper part 76, which can be removed in particular for the lateral removal of the steam blower box 12. In particular for this lateral removal of the steam blow box 12, the connection between the steam blow box 12 or the driver-side support element 64 and the driver-side actuating device 134, here for example a hydraulic cylinder, can also be released. For this purpose, a bolt 154 must be removed in the present exemplary embodiment (see FIG. 16 again, for example).

As can be seen from FIGS. 20 and 21, an adjusting device 146, for example comprising at least one cylinder / piston unit or at least one hydraulic cylinder, is also provided on the drive side for adjusting the steam blow box between the operating position and the maintenance position. In the present exemplary embodiment, this adjusting device 146 comprises a hydraulic cylinder. This drive-side actuating device 146 is detachably connected in particular to the drive-side support element 66. In particular for the lateral removal of the steam blower box 12, the connection between this or the drive-side support element 66 and the drive-side actuating device 146 can be released, for example, by removing a bolt 156 (cf. in particular again FIG. 21).

A lifting frame 148 is provided on the drive side, which can be raised such that the drive-side support element 66 connected to it lifts off the drive-side slide rail 132.

When the drive-side lifting frame 148 is raised, the drive-side end of the extension aid 20 provided with rollers 24 is also raised at the same time. At least one upper roller 24 of the extension aid 20 comes into contact with the inner wall of the steam distribution space 22 or the additional expansion pipe 38. With the lifting of the drive-side lifting frame 148, the entire drive-side end of the steam blow box 12 is finally raised.

In the present exemplary embodiment, with the lifting of the drive-side lifting frame 148, a locking bolt 48 passing through the drive-side end of the extension aid 20 and guided in elongated holes 150 of the drive-side bearing 46 is acted upon and carried along, and the drive-side end of the extension aid 20 is also lifted via this locking bolt 48 '.

The drive-side lifting frame 148 can be raised via an actuating device, which here comprises, for example, two cylinder / piston units or lifting cylinders 152. The drive-side lifting frame 148 can be adjusted in particular relative to the drive-side mounting 46 via this adjusting device 152.

The embodiment of the steam blower box unit shown in FIGS. 15 to 21 thus includes a bearing for extending the steam blower box 12 and for adjusting the steam blower box 12 between an operating position and a maintenance position.

A frame-like slide rail 130 is provided on the driver's side, on which the support element or support tube 64 rests during operation or slides from the operating position into the maintenance position and vice versa with the aid of the adjusting device 134.

A lifting frame 138 is also provided on the driver's side, with which rollers 136 and guide elements 142 are firmly connected. This operator-side lifting frame 138 is raised by the adjusting device 140, which comprises two hydraulic cylinders, for example, before the steam blow box is removed, as a result of which the rollers 136 with the support element or support tube 64 come into contact and thus lift the steam blower box off the slide rail 130. The guide elements 142 are guided in U-shaped guides 144, for example. Before moving out, the upper bearing part 76 must be dismantled and the connection to the actuating device 134 comprising, for example, a hydraulic cylinder must be released.

The work on the driver's storage therefore includes the following steps, for example:

Disassembly of the upper bearing part 76 Disassembly of the lifting cylinder pin 154 Pulling back the lifting cylinder 134 Lifting the system using the lifting cylinder 140 (e.g. by 17 mm)

The total stroke of 17 mm, for example, can be composed in particular as follows:

7 mm to raise the extension attachment until contact with the steam box 10 mm to raise the entire system

Work on the drive-side mounting can include the following steps, for example:

Disassembly of the flexible steam line 158 (cf. FIG. 20), disassembly of the lifting cylinder bolt 156 (cf. FIG. 21), withdrawal of the lifting cylinder 146 Position the extension aid or the extension tube 20 relative to the bore or the elongated holes 150 of the upper part 44 of the drive-side bearing 46 by pulling out the extension aid 20 - inserting the locking bolt 48 'through the holes or

Elongated holes 150 in the upper bearing part 44

Securing the system (extension aid 20 / steam blower box 12) with spring plugs which are inserted, for example, through the locking bolt 48 'and secure this in the desired position

Raising the drive-side lifting frame 148 by means of the adjusting device 152, for example comprising two short-stroke cylinders (e.g. by 22 mm)

The total stroke of 22 mm, for example, can be composed in particular as follows:

4 mm distance between the upper bearing part 44 and locking bolt 48 '8 mm distance between the upper roller 24 and the inner wall of the steam distribution chamber 22 or the additional extension pipe 38 10 mm to raise the entire system

Otherwise, the one shown in FIGS

Embodiment at least essentially have, for example, such a structure as described in connection with the other embodiments. LIST OF REFERENCE NUMBERS

Steam box unit

steam blow

web

withdrawable

suction roll

Extension aid, extension tube 'Extension aid

Steam pipe 'support pipe

Track rollers, ball rollers

zone chamber

Steam outlet plate

Control valve

dehydrator

insulation

blind flange

expansion pipe

T-shaped support

Valve on the drive-side bearing upper part on the drive-side bearing

Bolt 'locking bolt

connection

winch

excerpt rope

idler pulley

idler pulley Umlenkseil feeder cable guide sided support tube support member drive-side support tube, supporting element guide sided bearing rail sliding drive-side steam connection hydraulic or lift cylinder guide-side bearing shell adjusting screw adjusting spherical rollers fastening screw guide-side connection flange support frame guide-side flange end stop rack gear pliers rod pinion drive leader sided bearing part steam supply, vapor connection bores steam distribution chamber common center inflatable ring seal Bore Bore 116 contact surface on support tube 22 '

118 ring flange on extension tube 20, contact surface

120 flat steel for locking bolt 48 '

122 locking bolts 124 groove in the drive-side upper bearing part 44

126 Groove in the drive-side bearing support tube 66

128 Working area of the ring seal

130 operator-side slide rail

132 drive-side slide rail 134 driver-side actuating device, cylinder / piston unit

136 Roller of the operator's lifting frame

138 operator-side lifting frame

140 driver-side actuator, cylinder / piston unit

142 guide element 144 U-shaped guide

146 drive-side actuator, cylinder / piston unit

148 drive-side lifting frame

150 slots

152 drive-side actuator, cylinder / piston unit 154 bolts

156 bolts

158 flexible steam pipe

FS driver side L web direction

TS drive side

Claims

Patent claims 1. steam box unit (10) with a steam box (12) for applying steam to a passing material web (14), in particular paper or cardboard web, and with an at least partially integrated in the steam box (12) extension device (16), via which the in an operating position of the material web (14) opposite the steam blow box (12) laterally, ie is generally transverse to the web running direction (L), can be moved out of its operating position and can be retracted into this operating position from a lateral position. 2. Steam blower box unit according to claim 1, characterized in that the entire steam blower box (12) can be moved correspondingly via the extension device (16). 3. A steam blower box unit according to claim 1 or 2, characterized in that the extension device (16) comprises an extension aid (20, 20 ') which can be inserted in the steam blower box (12) and through which the steam blower box (12) is guided when it is moved out or in. 4. steam blower box unit according to claim 3, characterized in that the extension aid (20, 20 ') has an elongated shape and extends in the inserted state generally transversely to the web running direction (L). 5. Steam blower box unit according to one of the preceding claims, characterized in that the extension aid (20, 20 ') for extending and / or retracting the steam blower box (12) can be used in the steam blower box (12) and then removed again. 6. steam blower box unit according to one of claims 1 to 4, characterized in that the extension aid (20, 20 ') remains inserted during operation of the steam blower box (12). 7. Steam blower box unit according to one of the preceding claims, characterized in that the extension aid (20) can be used in a steam distribution chamber (22), in particular steam pipe, of the steam blower box (12) extending generally transversely to the web running direction (L). 8. Steam blower box unit according to one of the preceding claims, characterized in that the extension aid (20) can be used in an additional expansion pipe (38) of the steam blower box (12) which extends generally transversely to the web running direction (L). 9. steam blower box unit according to one of the preceding claims, characterized in that the steam distribution space (22) or the additional extension pipe (38) is designed such that the steam blower box (12) can be extended or retracted laterally, guided by the extension aid (20). 10. Steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) is designed such that its upper part is available as a space for the extension aid (20, 20 '). 11. Steam blower box unit according to one of the preceding claims, characterized in that the extension aid comprises an extension tube (20). 12. Steam blower box unit according to claim 11, characterized in that the extension tube (20) and the relevant receptacle (22, 38) of the steam blower box (12) are convex. 13. Steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) on the driver side and carrier side is each provided with a spherical support tube (64, 66) which is received in a respective bearing (46, 48), the running surfaces the bearings (46, 48) preferably have a shape complementary to the spherical support tubes (64, 66). 14. A steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) comprises a support (40) which extends generally transversely to the web running direction (L) and is preferably T-shaped in cross section, and that one for extending or retracting the steam blower box (12) with this support (40) interacting extension aid (20 ') is provided. 15. A steam blower box unit according to one of the preceding claims, characterized in that rollers (24) are provided between the extension aid (20, 20 ') and the wall of the steam distribution space (22) or the support. 16. Steam blower box unit according to one of the preceding claims, characterized in that the extension aid (20, 20 ') can be inserted into an upper region of the steam blower box (12). 17. Steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) can be extended in the direction of the driver's side. 18. Steam blower box unit according to claim 17, characterized in that the extension aid (20, 20 ') can be axially fixed, in particular on the upper part (44) of a drive-side bearing (46). 19. Steam blower box unit according to claim 18, characterized in that the axially fixed extension aid (20) is simultaneously secured against rotation about its longitudinal axis. 20. Steam blower box unit according to claim 18 or 19, characterized in that the axially fixed extension aid (20) can simultaneously be pivoted about a preferably horizontal axis (48) perpendicular to its longitudinal axis. 21. Steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) has a connection on the driver's side (50) is provided, to which a crane, a cable winch (52) and / or the like can be connected. 22. Steam blower box unit according to one of the preceding claims - before, characterized in that the extension device (16) comprises a pull-out rope (54), a deflection rope (60) and / or guided in particular via deflection rollers (56, 58) attached to the extension aid (20) comprises a pull-in rope (62). 23. Steam blow box unit according to one of the preceding claims, characterized in that the steam blow box (12) can be extended or retracted via a rack and pinion gear (92). 24. A steam blower box unit according to claim 23, characterized in that a rack (94) is provided on the underside of the steam blower box (12) and / or preferably on the underside of a support tube (64) associated with the steam blower box (12) a drivable pinion (96) can be brought into engagement. 25. Steam blower box unit according to one of the preceding claims, characterized in that the extension tube (20) serves at the same time for the steam supply. 26. A steam blower box unit according to claim 25, characterized in that the extension tube (20) remains inserted in the steam blower box (12) even during operation. 27. Steam blow box unit according to claim 25 or 26, characterized in that the extension tube (20) can be inserted into a support tube (22 ') of the steam blow box (12) which extends generally transversely to the web running direction (L). 28. Steam blower box unit according to claim 27, characterized in that the area (W) between the extension tube (20) and the support tube (22 ') is sealed by an inflatable ring seal (110). 29. Steam blower box unit according to one of the preceding claims, characterized in that the steam blower box (12) is provided on the driver side and / or drive side with a supporting element (64, 66) which, in operation, on a driver side or drive side slide rail (130, 132) rests. 30. Steam blower box unit according to claim 29, characterized in that the slide rail (130, 132) is assigned to a driver-side or drive-side mounting (68 or 46). 31. The steam blower box unit as claimed in claim 30, characterized in that the slide rail (130, 132) is fixedly connected to the driver-side or drive-side mounting (68 or 46). 32. Steam blower box unit according to one of claims 29 to 31, characterized in that the steam blower box (12) on the slide rails (130, 132) is adjustable between an operating position and a maintenance position. 33. The steam blower box unit according to claim 32, characterized in that the steam blower box (12) has a relatively greater distance from the passing material web (14) in its maintenance position than in its operating position. 34. Steam blower box unit according to claim 30 or 31, characterized in that an adjusting device (134) comprising at least one cylinder / piston unit is provided at least on the driver's side for adjusting the steam blower box (12) between the operating position and the maintenance position. 35. Steam blower box unit according to claim 34, characterized in that the driver-side actuating device (134) can be connected to the driver-side support element (64). 36. Steam blower box unit according to one of claims 29 to 35, characterized in that at least one frame-like slide rail (130, 132) is provided. 37. Steam blower box unit according to one of claims 29 to 36, characterized in that the support elements are each designed as a support tube (64, 66). 38. steam blower box unit according to one of claims 29 to 37, characterized in that on the driver side with at least one roller (136) Provided lifting frame (138) is provided, which can be raised so that the roller (136) comes into contact with the driver-side support element (64) and lifts the driver-side support element (64) from the driver-side slide rail (130). 39. The steam blower box unit according to claim 38, characterized in that the driver-side lifting frame (138) can be raised by means of an adjusting device (140) comprising in particular at least one cylinder / piston unit. 40. steam blower box unit according to one of claims 29 to 39, characterized in that the driver-side lifting frame (138) is adjustable relative to the driver-side mounting (68). 41. Steam blower box unit according to one of claims 37 to 40, characterized in that guide elements (142) which are fixedly connected to the driver-side lifting frame (138) have a U-shaped cross section in particular Guides (144) are guided. 42. Steam blower box unit according to claim 41, characterized in that the guides (144) are fixedly connected to the driver-side mounting (68). 43. steam blower box unit according to one of claims 29 to 42, characterized in that the driver-side support element (64) at generally transverse to Direction of web travel (L) when the steam blower box (12) moves out of its operating or maintenance position as well as when it retracts on the roller (136) assigned to the lifting frame (138) on the driver's side. 44. Steam blower box unit according to one of claims 29 to 43, characterized in that at least two rollers (136) are assigned to the driver-side lifting frame (138). 45. Steam blower box unit according to one of claims 29 to 44, characterized in that the driver-side mounting (68) is provided with an upper part (76) which can be removed in particular for the lateral removal of the steam blower box (12). 46. Steam blower box unit according to one of claims 29 to 45, characterized in that, in particular for the lateral removal of the steam blower box (12), the connection between the steam blower box (12) or the driver-side support element (64) and the driver-side actuating device (134) is solvable. 47. Steam blower box unit according to one of claims 29 to 46, characterized in that an adjusting device (146) comprising at least one cylinder / piston unit is provided at least on the drive side for adjusting the steam blower box (12) between the operating position and the maintenance position. 48. Steam blower box unit according to claim 47, characterized in that the drive-side actuating device (146) can be connected to the drive-side support element (66). 49. Steam blower box unit according to one of claims 29 to 48, characterized in that a lifting frame (148) is provided on the drive side which can be raised such that the drive-side support element (66) connected to it lifts off the drive-side slide rail (132). 50. Steam blower box unit according to claim 49, characterized in that when the drive-side lifting frame (148) is raised, the drive-side end of the one provided with rollers (24) is simultaneously lifted Extension aid (20, 20 ') is raised, at least one upper roller (24) of the extension aid (20, 20') coming into contact with the inner wall of the steam distribution space (22) or the additional expansion pipe (38). 51. Steam blower box unit according to claim 50, characterized in that the lifting of the drive-side lifting frame (148) finally also raises the entire drive-side end of the steam-blowing box (12). 52. Steam blower box unit according to claim 50 or 51, characterized in that with the lifting of the drive-side lifting frame (148) a drive-through end of the extension aid (20, 20 ') penetrating in long holes (150) of the drive-side mounting (46) guided locking bolt (48 ') and the drive-side end of the extension aid (20, 20') is raised with this locking bolt (48 '). 53. Steam blower box unit according to one of claims 29 to 52, characterized in that the drive-side lifting frame (148) can be raised by means of an adjusting device (152) comprising in particular at least one cylinder / piston unit. 54. Steam blower box unit according to one of claims 29 to 53, characterized in that the drive-side lifting frame (148) is adjustable relative to the drive-side bearing (46). 55. Steam blower box unit according to one of claims 29 to 54, characterized in that the connection between the steam blower box (12) or the drive-side support element (66) and the drive-side actuating device (146) is detachable, in particular for the lateral removal of the steam blow box (12) , 56. Method for moving a steam blow box (12) out of its operating position opposite a material web (14) to be treated, in which an extension device (16) integrated at least partially in the steam blow box (12) is used to move the steam blow box (12) laterally, ie generally transverse to the web running direction (L), move out of the operating position and then move back into this operating position. 57. The method according to claim 56, characterized in that the entire steam blow box (12) is moved accordingly by means of the extension device (16). 58. The method according to claim 56 or 57, characterized in that an extension device (16) is used with an extension aid (20, 20 ') which can be inserted into the steam blower box (12) and through which the steam blower box (12) is guided when moving out or in becomes. 59. Method according to claim 58, characterized in that an extension aid (20, 20 ') having an elongated shape is used, which in the inserted state extends generally transversely to the web running direction (L). 60. Method according to one of the preceding claims, characterized in that the extension aid (20, 20 ') for extending and / or retracting the steam blower box (12) is inserted into the steam blower box (12) and then removed again. 61. The method according to any one of claims 56 to 59, characterized in that the extension aid (20, 20 ') is left in the steam blow box (12) even during operation. 62. Method according to one of the preceding claims, characterized in that the extension aid (20) is used in a steam distribution chamber (22), in particular steam pipe, of the steam blow box (12) which extends generally transversely to the web running direction (L). 63. Method according to one of the preceding claims, characterized in that the extension aid (20) is inserted into an additional expansion pipe (38) of the steam blow box (12) which extends generally transversely to the web running direction (L). 64. The method according to any one of the preceding claims, characterized in that a steam blower box (12) is used, the steam distribution chamber (22) or additional extension pipe (38) is designed such that the steam blower box (12) is guided by the extension aid (20 ) can be extended or retracted laterally. 65. Method according to one of the preceding claims, characterized in that an extension tube (20) is used as an extension aid. 66. The method according to claim 63, characterized in that the extension tube (20) and the relevant receptacle (22, 38) of the steam blow box (12) are of spherical design. 67. The method according to any one of the preceding claims, characterized in that that a steam blower box (12) with a generally cross-sectionally T-shaped carrier (40) extending transversely to the web running direction (L) is used and that one for interacting with this carrier (40) for extending or retracting the steam blower box (12) Extension aid (20 ') is used. 68. Method according to one of the preceding claims, characterized in that rollers (24) are used between the extension aid (20, 20 ') and the wall of the steam distribution space (22) or the support. 69. Method according to one of the preceding claims, characterized in that the extension aid (20, 20 ') is inserted into an upper region of the steam blow box. 70. Method according to one of the preceding claims, characterized in that the steam blower box (12) is extended in the direction of the driver's side. 71. The method according to claim 70, characterized in that the extension aid (20, 20 ') is fixed axially, in particular on the upper part (44) of a drive-side bearing (46). 72. The method according to claim 71, characterized in that that the axially fixed extension aid (20) is simultaneously secured against rotation about its longitudinal axis. 73. The method according to claim 71 or 72, characterized in that the axially fixed extension aid (20) is at the same time pivotally mounted about a preferably horizontal axis (48) perpendicular to its longitudinal axis. 74. Method according to one of the preceding claims, characterized in that the steam blow box (12) is extended or retracted using a crane, a cable winch and / or the like. 75. The method according to any one of the preceding claims, characterized in that the steam blower box (12) using a pull-out cable (54), in particular a guide rope (60) and / or guided over guide pulleys (56, 58) attached to the extension aid (20) one Retractable rope (62) is extended or retracted. 76. Method according to one of the preceding claims, characterized in that the steam blow box (12) is extended or retracted using a rack and pinion gear (92). 77. The method according to claim 76, characterized in that the steam blow box (12) using a rack (94) is extended or retracted, which is preferably provided on the underside of the steam blow box (12) and / or preferably on the underside of a support tube (64) assigned to the steam blow box on the driver's side, with this rack (94) being a drivable pinion (96 ) is engaged. 78. Method according to one of the preceding claims, characterized in that the extension tube (20) is used simultaneously for the steam supply. 79. The method according to claim 78, characterized in that the extension tube (20) is left in the steam blow box (12) even during operation of the steam blow box. 80. The method according to claim 78 or 79, characterized in that the extension tube (20) is inserted into a support tube (22 ') of the steam blow box (12) which extends generally transversely to the web running direction (L). 81. The method according to claim 80, characterized in that the area (W) between the extension tube (20) and the support tube (22 ') is sealed by an inflatable ring seal (110).