EP2845664A1 - Method and device for producing a corrugated metal pipe - Google Patents

Abstract

The invention relates to a method for producing a tube (5) of corrugated metal transversely to its longitudinal direction, which receives a corrugation consisting of corrugation peaks and troughs. In this case, a shaft device is used, which presses a first corrugation in the in its longitudinal direction through the same moving tube. The distance between the wave crests is then reduced to achieve a second corrugation by a voltage applied to the pipe, consisting of two separate clamping devices (10, 11) clamping unit. Both tensioning devices (10, 11) are fixed one after the other in the radial direction against the tube (5) provided with the corrugation. A first, equipped with a drive clamping device (10) is moved in the working position at the same speed as the tube (5) with the same. The tube (5) provided with the first corrugation is continuously pressed by the first clamping device (10) against a fixed point realized by the second (11), likewise equipped with a drive clamping device (11), which in the working position relative to the shaft means in axial Direction behind the first tensioning device (10) is arranged. Both clamping devices (10, 11) are cyclically removed from the tube and in the opposite direction to the direction of movement of the tube (5) each moved back to a new position and applied in this new position again in the two different areas of the tube (5).

Description

The invention relates to a method for producing a corrugated metal tube transversely to its longitudinal direction, which receives a corrugation consisting of wave crests and troughs, in which a wave device is used, which a first corrugation as Vorwellung in the longitudinal direction through the same moving tube is pressed, with a given axial distance between the wave crests thereof, and in which the distance between the wave crests is subsequently reduced to obtain a second corrugation by a voltage applied to the tube clamping unit and to an apparatus for performing the method ( CH 496 490 A ).

Methods and apparatus for producing tubes corrugated transversely to their longitudinal direction have been known and used for years. The pipes are well bendable by the corrugation and stable against radial loads. The corrugation may be helical or annular. This is made possible with corresponding devices which press the corrugation in a smooth tube moved in its longitudinal direction. Such tubes can be used to transport liquid or gaseous media. They can also be used as electrical conductors for high frequency cables or as sheaths for power cables and communication cables. The degree of bendability depends substantially on the axial distance of the wave crests from each other and on the depth of the corrugation, d. H. from the radial difference of the wave crests and the respective adjacent troughs.

From the DE 24 00 842 A1 Go forth a method and an apparatus for producing a highly flexible tube with a corrugation, the wave crests are close together and has a relatively deep corrugation. The tube is after the embossing of the corrugation in a corrugated device by a trigger device pressed against an annular tool and thereby compressed, whereby the axial distance of the wave crests is reduced from each other.

The initially mentioned CH 496 490 A describes a corrugating device for tubes, which has a first arrangement, with which in a smooth tube step by step, discontinuously annular notches are pressed. The tube provided with a corrugation produced by the notches is fed to a second arrangement in which the axial distance between the crests of the undulations produced in the first arrangement is reduced. The second arrangement consists of three parts, which are connected to each other via effective in the axial direction of the tube springs. The three parts cooperate in a two-stage operation, compress the corrugation of the corrugated tube and cause a feed movement of the tube through the first arrangement by one step. In the first arrangement, a further annular notch is then pressed into the tube.

The invention has the object of developing the initially described method and the associated device so that a continuous production of a corrugated tube with compressed corrugation is possible.

• daß eine aus zwei voneinander getrennten Spannvorrichtungen bestehende Spanneinheit eingesetzt wird, die beide in radialer Richtung hintereinander fest an das mit der Wellung versehene Rohr angelegt werden,
• daß eine erste, mit einem Antrieb ausgerüstete Spannvorrichtung in Arbeitsstellung mit gleicher Geschwindigkeit wie das Rohr mit demselben mitbewegt wird,
• daß das mit der Wellung versehene Rohr durch die erste Spannvorrichtung kontinuierlich gegen einen durch die zweite, ebenfalls mit einem Antrieb ausgerüstete Spannvorrichtung realisierten Festpunkt gedrückt wird, die in Arbeitsstellung bezogen auf die Welleinrichtung in axialer Richtung hinter der ersten Spannvorrichtung angeordnet ist, und
• daß beide Spannvorrichtungen zyklisch vom Rohr abgenommen und in Gegenrichtung zur Bewegungsrichtung des Rohres jeweils in eine neue Position zurückbewegt und in dieser neuen Position wieder in den beiden unterschiedlichen Bereichen an das Rohr angelegt werden.

This object is achieved according to the invention characterized

• a tensioning unit consisting of two separate tensioning devices is used, both of which are fixed one behind the other in the radial direction to the corrugated pipe,
• that a first, equipped with a drive clamping device is moved in the working position at the same speed as the tube with the same,
• in that the tube provided with the corrugation is continuously pressed by the first clamping device against a fixed point realized by the second clamping device also equipped with a drive, which in the working position is arranged behind the first clamping device in the axial direction relative to the shaft device, and
• that both clamping devices are cyclically removed from the tube and moved back in the opposite direction to the direction of movement of the tube in each case in a new position and applied in this new position again in the two different areas of the pipe.

This method and the corresponding device work continuously. The tube is moved without interruption in its longitudinal direction by the shaft means and accordingly provided continuously with a first corrugation. This first corrugation is a pre-corrugation that is subsequently compressed to the desired corrugation. The tube is first corrugated in a known technique without significant material stress. The narrower or deeper corrugation is then achieved by the interaction of the two tensioning devices, which rest firmly against the same in different regions of the tube. The second clamping device is adjusted so that it acts as a kind of fixed point or realized a fixed point against which the first clamping device presses the corrugated tube with continuous feed. The wave crests of the corrugated tube are brought closer to each other, so that there is a tube that has an increased flexibility.

Both fixtures are moved back with short-term release of the tube in a cyclic order opposite to the direction of movement of the tube and put back on the pipe. For example, this can be done for the first clamping device when two peaks are pressed together. With appropriate effort, the cyclical return movement of at least the first clamping device can also be carried out after each compressed crest. This cyclical return movement of the tensioning devices can also take place when more than two wave crests are compressed. Both fixtures can be moved back simultaneously. Advantageously, however, they are moved back in time, so that always one of the clamping devices rests in the associated area on the pipe.

The distance of the peaks in the compressed region of the tube from each other can be adjusted by the type of movement to be used for the second clamping device. Thus, the second tensioning device can also be moved with the tube, but with a relation to the speed of the first tensioning device lower speed. The second clamping device can also, without the use of their drive, so at rest, only be applied firmly to the pipe. It is also possible to drive the second clamping device during continuous production in the direction opposite to the direction of movement of the first clamping device.

The two clamping devices are advantageously made of two parts designed as half shells, which can be locked together in the working position and then form a ring. But it can also be used consisting of more than two parts clamping devices. The parts of the clamping devices can rest in the working position only sufficiently firmly outside on the respective areas of the tube. Advantageously, at least the first clamping device but on its inner surface at least one annular or helically extending rib, which engages in a working position in a wave trough of the corrugated tube. For the cyclical return movement of the two clamping devices whose parts only need to be unlocked and removed from the pipe as well as in the new position to be applied to the same again. The return movement of the two clamping devices can advantageously be carried out automatically, for example by means of their drives or by separate drives.

Method and apparatus according to the invention will be explained with reference to the drawings as embodiments.

• Fig. 1 in schematischer Darstellung eine Vorrichtung zur Durchführung des Verfahrens nach der Erfindung.
• Fig. 2 eine Einzelheit aus Fig. 1 in vergrößerter Darstellung.
• Fig. 3 unterschiedliche Positionen eines gewellten Rohres und von bei Durchführung des Verfahrens eingesetzten Bauteilen.

Show it:

• Fig. 1 a schematic representation of an apparatus for carrying out the method according to the invention.
• Fig. 2 a detail Fig. 1 in an enlarged view.
• Fig. 3 different positions of a corrugated tube and components used in carrying out the method.

With the method and the device according to the invention, a corrugation is pressed into an initially smooth tube of metal, preferably of steel. The tube can basically be a prefabricated tube in any desired way.

In the following description, a per se known technique for producing a smooth tube will be described which is corrugated with the method and apparatus of the invention after its manufacture. The corrugation can be helical, but advantageously designed ring-shaped.

According to Fig. 1 is drawn from a coil 1, preferably consisting of steel strip 2 and fed in the direction indicated by an arrow P direction of a forming unit 3. In the forming unit 3, the band 2 is longitudinally formed into a slit tube in which the two edges of the band 2 abut each other at a longitudinal slot. The slot is welded in a welding device 4, whereby a completely closed, smooth tube 5 is generated. For the movement of the belt 2 and the tube 5 produced therefrom, a generally known trigger 6 is used. The trigger 6 may be, for example, a caterpillar take-off or a jaw trigger.

The finished smooth tube 5 then passes into a shaft device 7, in which a transverse to its longitudinal direction corrugation is pressed as Vorwellung in the same, which - as already mentioned - preferably extends annularly. The pre-corrugated tube 5 goes out of the left part of Fig. 2 out. The vorgewellte tube 5 is then fed to a clamping unit 8, whose structure and operation on the basis of Fig. 2 and 3 be explained. By means of the clamping unit 8, the Vorwellung is compressed. The shape of the tube 5 provided with a compressed corrugation comes from the right side of the Fig. 2 out. The then finished tube 5 can be wound onto a coil 9.

The clamping unit 8 consists of two separate clamping devices 10 and 11, which rest firmly in working position at different areas of the tube 5. They are parallel to the axis of the tube 5 in the direction of the double arrows 12 and 13 displaced. For this purpose, the two tensioning devices 10 and 11 may be guided, for example, along a schematically indicated guide element, for example a rail 14.

The clamping devices 10 and 11 are designed for example as half shells, which are locked in working position under fixed contact with the pipe 5 to form a ring. Both clamping devices 10 and 11, engage in working position in the corrugation of the tube 5 a. They are at the beginning of the process on the pre-corrugated pipe 5 at. When carrying out the method, the tensioning device 10 continues to rest in the region 15 of the pre-corrugated tube 5, while the tensioning device 11 then abuts the compressed region 16 of the tube 5 with the compressed corrugation during continuous production.

• Das Rohr 5 wird der Spanneinheit 8 mit konstanter Geschwindigkeit kontinuierlich zugeführt. Deren beide Spannvorrichtungen 10 und 11 werden gemäß Fig. 3a mit axialem Abstand zueinander an das mit der Vorwellung versehene Rohr 5 angelegt. Die Spannvorrichtung 10 läuft danach mit der gleichen Geschwindigkeit wie das Rohr 5 mit demselben mit. Sie wird dabei von einem nicht mit dargestellten Antrieb angetrieben.

The method according to the invention operates on the basis of the illustrations in FIG Fig. 3 which, for the sake of simplicity, show only the corrugation and not the whole pipe, for example as follows:

• The tube 5 is fed continuously to the clamping unit 8 at a constant speed. The two tensioners 10 and 11 are according to Fig. 3a at an axial distance from each other to the pre-corrugated tube 5 is applied. The tensioning device 10 then runs at the same speed as the tube 5 with the same. It is driven by a non-illustrated drive.

The tensioning device 11 is also equipped with a drive. To further explain the method, it is first assumed that the clamping device 11 is held stationary by its drive at the beginning of the process. The tensioning device 11 then holds the tube 5 at the point where it is applied to the same. As a result, it realizes a fixed point against which the tube 5 provided with the pre-corrugation is pressed by the first clamping device 10. The corrugation of the tube 5 is thereby compressed so that the distance between the wave crests is reduced. In this way, by the advance of the first tensioning device 10, for example, three wave crests are compressed, as shown in FIG Fig. 3b is shown.

At least the tensioning device 10 must then be moved back in the opposite direction to the direction of movement of the tube 5 according to the arrow 17 until they are out of Fig. 3c has an apparent new position. The second jig 11, which holds the tube 5 only firmly, could initially maintain their position, but it can also in the direction of arrow 18 in the off Fig. 3c be moved back apparent position. For the return movement, the clamping devices 10 and 11 are first removed from the tube 5 by the annularly joined parts are detached from each other. In the respective new position, the parts of the two clamping devices 10 and 11 are reassembled into a ring and locked together.

After the repositioning of at least the first tensioning device 10, the substantially same process takes place as it does for Fig. 3a is described. There are then compressed, for example, three other peaks, so that an image as shown in Fig. 3d results. The two tensioning devices 10 and 11 are moved back in the described sense with advantage successively, so that always a clamping device rests on the tube 5.

The process continues in this sense with cyclically following return movement of the two tensioning devices 10 and 11 with continuous advancement of the tube 5 until a predetermined number of wave crests of the pre-corrugated tube 5 is compressed. A corresponding tube 5 goes out Fig. 3e out. In this case, the first tensioning device 10 is only shown with fullness for the sake of simplicity.

The same operation of the method applies even if the second tensioning device 11 is driven with respect to the speed of the first tensioning device 10 lower speed and moved with the tube 5 in the direction of movement. The distance of the compressed wave crests is then greater than in the embodiment with fixedly held second clamping device 11. If the second clamping device 11 is driven in a further variant of the method in the direction opposite to the direction of movement of the first clamping device 10 and 5 of the tube, results in a Tube 5, whose peaks are compressed denser than in the embodiment with fixedly held second clamping device 11.

Claims (6)

A method for producing a corrugated metal pipe transversely to its longitudinal direction, which receives a corrugation consisting of wave crests and troughs, in which a shaft device is used, which presses a first corrugation as a pre-corrugation in the in its longitudinal direction through the same moving pipe, with a given axial distance between the wave crests of the same, and in which the distance between the wave crests is subsequently reduced to obtain a second corrugation by a voltage applied to the tube clamping unit, characterized - That one of two separate clamping devices (10,11) existing clamping unit is used, both in the radial direction one behind the other firmly against the provided with the corrugated tube (5) are applied, - That a first, equipped with a drive clamping device (10) is moved in the working position at the same speed as the tube (5) with the same, - That provided with the corrugated tube (5) by the first clamping device (10) continuously against a by the second, also equipped with a drive clamping device (11) realized fixed point is pressed in the working position relative to the shaft means (7) in axial direction behind the first tensioning device (10) is arranged, and - That both clamping devices (10,11) cyclically removed from the tube (5) and in the opposite direction to the direction of movement of the tube each moved back to a new position and created in this new position again in the two different areas of the tube (5). A method according to claim 1, characterized in that the second tensioning device (11) is driven in the same direction as the first tensioning device (10) but at a lower speed than the same. A method according to claim 1, characterized in that the second tensioning device (11) is driven opposite to the direction of movement of the first tensioning device (10). Method according to Claim 1, characterized in that the second tensioning device (11) is firmly applied to the tube (5) without the use of its drive. Apparatus for carrying out the method according to one of claims 1 to 4, characterized in that the two clamping devices (10,11) consist of at least two parts which are connected in working position to form a closed ring which rests firmly on the tube (5) , Apparatus according to claim 5, characterized in that the parts of the clamping devices (10,11) have at least one radially inwardly facing rib which engages in working position in the corrugation of the tube (5).

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