Apparatus and system for expanding a tube and method for adjusting the diameter of the apparatus

Abstract

The invention relates to a device 10 and system for expanding a pipe as well as a method for adjusting the diameter of the device 10. The device 10 comprises a drive shaft 20, a receiving disk 30 arranged on the drive shaft 20, which has a plurality of receptacles 32 extending from the inside to the outside, a plurality of rotatably mounted forming rollers 40, wherein the forming rollers 40 each have a first end 41 arranged on one of the receptacles 32 and continuously adjustable in the receptacle 32 and a second, freely projecting end 42 and a forming insert 50, 70, 80, 90, 100 which is detachably arranged between the forming rollers 40.In order to provide a device 10, a system and a method for expanding a pipe in which a large number of diameters can be set particularly simply and efficiently, but also with good accuracy, it is provided that the desired diameter can be set easily and precisely by means of the easily detachable mold insert 50, 70, 80, 90, 100.

Description

[0001] The invention relates to a device and a system for expanding a pipe and a method for adjusting the diameter of the device.

[0002] Devices for expanding pipes, also known as pipe expanders, of the type mentioned above are known in a variety of designs from the prior art and are used to expand pipes at one end so that they can be connected to a pipe of the same diameter. Pipe expanders designed for processing pipes of a fixed diameter are primarily used.

[0003] Pipe expanders that can be adjusted to various pipe diameters are also known from the state of the art. Where this is continuously adjustable, problems usually arise with the accuracy of the pipe diameter adjustment.

[0004] From EP 0 887 126 B1 a pipe expander is known in which different diameters can be set by swapping elements.

[0005] From DE 558 715 A a multi-part device for expanding brake drums by means of a die is known.

[0006] Based on this, the object of the invention is to provide a device, a system and a method for expanding a pipe, in which a large number of diameters can be set particularly simply and efficiently, but also with good accuracy.

[0007] The present invention solves this problem by a device having the features of claim 1, a system according to claim 14 and a method according to claim 15. Advantageous further developments are specified in the dependent claims.

[0008] According to the invention, the device for expanding a pipe comprises a drive shaft, a receiving disc arranged on the drive shaft, which has a plurality of receptacles extending from the inside to the outside, a plurality of rotatably mounted forming rollers, wherein the forming rollers each have a first end arranged on one of the receptacles and continuously adjustable in the receptacle and a second, freely projecting end, and a forming insert which is detachably arranged between the forming rollers.

[0009] The drive shaft serves to drive and transmit power from a drive device to the pipe expanding device. The drive device can be, for example, a cordless screwdriver or a drill. Accordingly, the drive shaft can be compatible with such motorized devices. The drive shaft can be designed, for example, as a round shaft or—preferably—as a hexagon.

[0010] The receiving disc is arranged on the drive shaft. To ensure optimal rotation around the drive shaft's axis of rotation, i.e., its longitudinal axis, the drive shaft is preferably arranged centrally on the receiving disc. The receiving disc is particularly preferably circular. The drive shaft is preferably arranged so that it penetrates the receiving disc.

[0011] The receiving disc has a plurality of receptacles for the forming rollers extending from the inside outward. Each receptacle enables a connection to a forming roller, in particular to an axle element of a forming roller, that is adjustable along its length. According to the invention, the receptacles are a type of rail. An "inside-out" arrangement can be understood to mean that the receptacles extend from the center point to the outer edge of the receiving disc. A plurality of receptacles can be understood to mean that at least three, preferably at least five, and particularly preferably six receptacles are arranged on the receiving disc.

[0012] A plurality of rotatably mounted forming rollers are each arranged on the receptacles. Rotatably mounted can be understood to mean that the forming rollers are mounted such that they rotate about their own longitudinal axis. The forming rollers preferably comprise an axle element that is fixed relative to the receptacle disk and a roller element that is freely rotatable about this axle element. Preferably, six forming rollers are arranged on six receptacles. Particularly preferably, the number of forming rollers corresponds to the number of receptacles. Alternatively, more receptacles than forming rollers can be provided, so that a smaller number of forming rollers can be arranged in the receptacles only as needed.

[0013] The forming rollers each have a first end arranged on one of the receptacles and continuously adjustable in the receptacle, and a second, freely projecting end. The first end is provided to ensure a connection to the receptacle in order to achieve attachment to the receiving disk. A fastening element for connection to the receptacle can be arranged at the first end of the forming roller, e.g. a nut that is screwed to an axle element of the forming roller. According to the invention, the first end is continuously adjustable in the receptacle. Continuously adjustable can be understood to mean that the first end - when loosened - is arranged so that it can be moved freely in the receptacle. The continuous adjustability ensures that the forming roller can be arranged and fixed in any desired position on the receptacle in order to suitably adjust the radius of the device.

[0014] According to the invention, the second end of the forming roller is freely cantilevered. "Freely cantilevered" means that the second end is not in contact with any other component of the device. The second end serves for positioning and inserting the device into the pipe and for expanding and expanding the pipe.

[0015] Furthermore, according to the invention, a forming insert is detachably arranged between the forming rollers. It can, for example, be removed axially between the forming rollers. Detachably arranged can be understood to mean that the forming insert can be removed freely or by releasing a detachable connection, i.e., for example, a screw, plug-in, or snap-in connection. The forming insert can be used to adjust the distance between the forming rollers and the center point of the receiving disk. As explained in more detail below, the forming insert can also ensure a transfer of force from the drive shaft to the forming rollers. Finally, the forming insert can stabilize the forming rollers during the expansion of a pipe. The forming insert is preferably cylindrical. The diameter can be selected according to the pipe diameter to be machined, for example in the range of 20 - 100 mm. The forming insert can, for example,be made of plastic or metal, whereby for reasons of strength metal, particularly aluminum, is preferred for smaller diameters of, for example, 30 mm or less, and plastic for larger diameters of more than 30 mm.

[0016] The device for expanding a pipe according to the invention is characterized by the ability to easily and precisely adjust the desired diameter using the easily removable forming insert. Because the forming rollers are mounted on only one side and have a freely projecting second end, the diameter can be adjusted over a wide range and the forming insert is easy to replace. Furthermore, the forming insert can also stabilize the forming rollers during expansion.

[0017] The invention further relates to a system for expanding a pipe, comprising a device for expanding a pipe as described above. The described mold insert is a first mold insert, and the system further comprises at least one second mold insert. The first and second mold inserts have different diameters. The first and second mold inserts can each be interchangeably attached to the device.

[0018] "Interchangeable" means that the mold insert can be replaced when the device is out of service. The first mold insert has a first diameter, while the second mold insert has a larger or smaller second diameter. The number of mold inserts, each with a different diameter, allows the system to be adapted to any pipe diameter.

[0019] Furthermore, the invention relates to a method for adjusting the diameter of the device for expanding a pipe as described above, comprising the steps: Removing a first mold insert, inserting a second mold insert and positioning the mold rollers to contact the second mold insert.

[0020] In order to make removal of the first mold insert particularly easy, it can be provided that the mold rollers are released and moved to an outer position, i.e. towards the outer edge, before removing the first mold insert. Release of the first mold insert can involve releasing a detachable connection, so that removal of the first mold insert is possible. In order to set a different diameter of the device, it is provided that a second mold insert with a diameter different from the first mold insert is inserted. After fastening the second mold insert, the mold rollers can be positioned by sliding them along the receptacles so that they are in contact with the mold insert. In order to position the mold rollers securely, they are preferably fixed in the receptacle.

[0021] According to an advantageous embodiment of the invention, the forming rollers are mounted on the receiving disk at an incline such that, when the receiving disk rotates in one direction of rotation, the second end of the forming rollers leads the first end in the direction of rotation. Accordingly, the first end can lead the second end in the opposite direction of rotation. An "inclined arrangement of the forming rollers on the receiving disk" can be understood to mean that the forming rollers are not arranged perpendicular to the receiving disk, but at an angle other than 90°. The inclination of the forming rollers is not radial, i.e., not in the direction of the radius of the receiving disk. The inclination is preferably such that the axis of rotation of the respective forming roller and the axis of rotation of the receiving disk do not lie in a common plane.

[0022] The inclination of the forming rollers can facilitate the insertion of the device into the interior of a pipe by rotating it in the direction of rotation. The inclination of the forming rollers creates an axial force component during rotation, which pulls the forming rollers axially into the pipe. After the pipe has been expanded and the device needs to be removed, the device can also be easily rotated out of the pipe by reversing the direction of rotation due to the inclination of the forming rollers, since the forming rollers, now facing opposite the direction of rotation, can move the device axially out of the pipe.

[0023] According to a particularly advantageous embodiment of the invention, the receptacles are formed at an angle to the receiving disk such that an angle in the range of 84° to 89.5°, particularly preferably 86.5° to 88°, is formed between the axes of rotation of the forming rollers and the receiving disk. The angle can be formed in the tangential direction of the receiving disk. The tangential direction is understood to be the direction that extends at a right angle to the radius. The axis of rotation of the forming rollers can be the axis around which the forming rollers rotate along the longitudinal axis. The axis of rotation of the forming rollers and the axis of rotation of the receiving disk can therefore have an angle between 0.5° and 6°, particularly preferably 2° to 3.5°.

[0024] According to a preferred embodiment of the invention, the forming rollers are arranged in a circle around the rotational axis of the drive shaft on the receiving disk, with opposing forming rollers being inclined in the opposite direction in the direction of rotation of the drive shaft. This circular arrangement allows the pipe to be expanded efficiently and while maintaining its shape. An opposing arrangement of the forming rollers means that all forming rollers are inclined in the direction of rotation of the drive shaft. Consequently, forming rollers arranged opposite one another along the circular path can face one another.

[0025] According to a particularly preferred development of the invention, the forming rollers each have a cylindrical fastening section for mounting on the receiving device and a conically shaped widening section, wherein the widening section tapers towards the second end of the forming rollers. The sections are preferably axial sections. The fastening section can serve to achieve a distance between the widening section and the receiving disk in order to enable a sufficient machining depth. The widening section can have a conical shape in order to achieve the widening when inserted into a pipe. Accordingly, the pipe can be easily widened to the desired diameter.

[0026] According to a preferred embodiment of the invention, a cylindrical stabilizing section is arranged between the expansion section and the fastening section, wherein the stabilizing section has a larger diameter than the fastening section. The cylindrical shape of this section can contribute to achieving a uniform shape of the expanded part of the pipe with the smoothest possible surface. The transition between the conical expansion section and the cylindrical stabilizing section is preferably continuous. A step is preferably formed at the transition between the cylindrical stabilizing section and the cylindrical fastening section of smaller diameter.

[0027] According to a particularly preferred embodiment of the invention, the mold insert has at least one rolling section of enlarged diameter in contact with the forming rollers for transmitting force between the mold insert and the forming rollers. The mold insert can thus have a wall section with a first diameter and the rolling section with a second, larger diameter. The wall section can correspond to those sections of the mold insert that are not part of the rolling section. The rolling section preferably has the largest diameter of all sections of the mold insert. The rolling section can serve for the efficient transmission of force from the mold insert to the forming rollers due to the contact created between the forming roller and the mold insert. To ensure efficient force transmission, the rolling section can comprise an elastic material.Particularly preferably, O-rings can be used on the rolling section for contact between the forming rollers and the forming insert.

[0028] According to an advantageous embodiment of the invention, the receptacles each have a guide groove on a first side of the receiving disc facing the drive shaft for radially adjustable reception of a fastening element of the forming roller, wherein a slot-shaped opening extending through the receiving disc runs along the guide groove. A guide groove can be formed, for example, in the form of an indentation or notch. A fastening element can be understood, for example, as a nut, a flange, an enlarged head, a ring or the like, with which a forming roller or, in particular, an axle element of a forming roller can be fastened to the receiving disc. The guide groove is preferably adapted to the size of the fastening element. Particularly preferably, the guide groove has a locking effect on the fastening element in order to prevent the fastening element from becoming loose during operation of the device.

[0029] Preferably, the holder can span a receiving plane, with the holder lying in the receiving plane. The receiving plane and the receiving disk can span an angle in the range of 0.5° to 6°, particularly preferably 2° to 3.5°. This can ensure an inclination of the forming rollers.

[0030] It is possible for the drive shaft to be non-rotatably mounted on the receiving disc, so that the receiving disc is driven directly by the drive shaft. However, according to a preferred embodiment of the invention, the drive shaft is rotatably mounted relative to the receiving disc, so that the receiving disc can rotate independently of the drive shaft. Rotatable mounting can be achieved, for example, by means of a ball bearing.

[0031] According to an advantageous embodiment of the invention, the drive shaft is coupled to the mold insert in a rotationally fixed manner, allowing efficient power transmission. To achieve this, for example, a projection arranged on the drive shaft can engage with an engagement opening in the mold insert. To further optimize and stabilize the connection between the drive shaft and the mold insert, a projection in the form of a pin can be provided on the drive shaft, while the mold insert has an engagement opening in the form of a groove.

[0032] According to a preferred embodiment of the invention, the mold insert is mounted on a locating pin on the side of the receiving disk opposite the drive shaft. The locating pin can improve the power transmission between the mold insert and the drive shaft and ensure a detachable connection to the mold inserts, e.g., a screw connection.

[0033] According to a particularly preferred embodiment of the invention, the drive shaft and the locating pin are formed as a single piece. To further reduce the number of components, the drive shaft can be provided with the locating pin. The integration of the locating pin into the drive shaft can further optimize stability and force transmission from the drive shaft to the mold insert.

[0034] Embodiments of the invention are set forth below with reference to the drawings. In the drawings: Fig. 1 a perspective view of a device for expanding a pipe; Fig. 2 a cross-section of the device along a section line AA according to Fig. 1 ; Fig. 3 a side view of the device Fig. 1 ; Fig. 4 a perspective exploded view of the device from Fig. 1 ; Fig. 5 an exploded perspective view of a pipe expanding system with multiple die inserts.

[0035] Fig. 1 shows an example of a device 10 for expanding a pipe with a drive shaft 20, a receiving disc 30, six forming rollers 40 and a forming insert 50.

[0036] The drive shaft 20 is designed as a hexagon so that it can be driven by a cordless screwdriver or drill.

[0037] The receiving disc 30 is arranged on the drive shaft 20 and has six receptacles 32 extending from the inside to the outside, see also Fig. 4 . The receptacles 32 each have, on a first side of the receiving disc 30 facing the drive shaft 20, a guide groove 38 for radially adjustable reception of a fastening element 48 of the forming roller 40, wherein a slot-shaped opening 36 extending through the receiving disc 30 runs along the guide groove 38, see also Fig. 4 A forming roller 40 is arranged on each of the receptacles 32. The forming rollers 40 extend axially substantially parallel to the longitudinal center axis, however—as explained below—not exactly parallel, but inclined in the tangential direction by an angle W1.

[0038] The rotatably mounted forming rollers 40 each have a first end 41 arranged on one of the receptacles 32 and continuously adjustable in the receptacle 32, and a second, freely projecting end 42. The forming rollers 40 are arranged in a circle around the rotational axis DA of the drive shaft 20 on the receiving disk 30.

[0039] How to continue Fig. 4 As can be seen, the forming rollers 40 each comprise an axle element 46, here a long screw, fixed relative to the receiving disc 30, a roller element 47 arranged to rotate freely around the axle element, and a fastening element 48, here a nut. Furthermore, a forming roller spring element 49, here a disc spring, is arranged between the roller element 47 and the receiving disc 30.

[0040] The roller elements 47 of the forming rollers 40 each have a cylindrical fastening section 43 for arrangement on the receptacle 32 and a conically shaped widening section 45, wherein the widening section 45 tapers towards the second end 42 of the forming rollers 40. Furthermore, a cylindrical stabilizing section 44 is arranged axially between the widening section 45 and the fastening section 43, wherein the stabilizing section 44 has a larger diameter than the fastening section 43. The outer diameter of the device 10 defined by the stabilizing sections 44 determines the inner diameter set when expanding a pipe.

[0041] The mold insert 50 is detachably arranged between the mold rollers 40, wherein the mold insert 50 is arranged rotatably relative to the receiving disc 30 and the mold rollers 40 and is in frictional contact with the mold rollers 40, see also Fig. 2 The mold insert 50 has a wall section 51 and a rolling section 52 with an enlarged diameter provided by three O-rings 53, which is in contact with the mold rollers 40 to ensure the force transmission between the mold insert 50 and the mold rollers 40. The three O-rings 53 are made of flexible material.

[0042] Fig. 2 shows the cross section of the device 10 along a section line AA according to Fig. 1 The mold insert 50 is arranged on a locating bolt 60 and fixed there by means of a screw 54. The locating bolt 60 is mounted on the side of the locating disk 30 opposite the drive shaft 20. In order to be driven by the drive shaft 20, the mold insert 50 is coupled to the drive shaft 20 by a projection 62 arranged on the drive shaft 20, here a pin, which engages in a groove 55 of the mold insert 50 (see Fig. 4 ). The drive shaft 20 is thus non-rotatably coupled to the mold insert 50.

[0043] The drive shaft 20 is formed in one piece with the locating bolt 60 and penetrates the locating disc 30, see Fig. 2 The drive shaft 20 is rotatably mounted relative to the receiving disc 30 by a ball bearing 34, in this case a deep groove ball bearing. Additionally, another ball bearing 34 is installed on the drive shaft 20 on the opposite side of the receiving disc 30.

[0044] Fig. 3 shows a side view of the device 10. The forming rollers 40 are mounted on the receiving disk 30 at an angle, so that when the receiving disk 30 rotates in one direction of rotation (in the example shown, anti-clockwise rotation), the second end 42 of the forming rollers 40 leads the first end 41 in the direction of rotation. The forming rollers 40 each rotate about their longitudinal axes, the rotational axes DF of the forming rollers 40, see Fig. 2 The longitudinal axis of the forming rollers 40 is defined by the longitudinal direction of the axle element 46. The axle element 46 penetrates the receiving disk 30 through the slot 36. The axle element 46 is mounted in the guide groove 38 by the fastening element 48, here a nut. The axis of rotation DF of the forming rollers 40 and the axis of rotation DA of the receiving disk 30 form an angle W1, which in the example shown is approximately 3°. The inclination of the forming rollers 40 relative to the receiving disk 30 results from the inclination of the receptacles 32 on the receiving disk 30. The receptacles 32 each define a receiving plane AE running through the receptacle 32, which forms an angle W2 with the receiving disk 30, which in the example shown is approximately 3°.

[0045] The receptacles 32 are consequently formed obliquely to the receiving disc 30, so that an angle in the range of approximately 87° in the tangential direction of the receiving disc 30 is formed between the axes of rotation DF of the forming rollers 40 and the receiving disc 30.

[0046] In order to connect a pipe, e.g. a thin-walled metal pipe such as a downpipe from a rain gutter, to another pipe of the same diameter, it is necessary to expand one of the pipes at one end so that the pipes can then be inserted into one another. The pipe is expanded by placing the second end of the forming rollers 40 against the end of the pipe so that the second end protrudes slightly into the pipe. By driving the drive shaft 20 in a first direction of rotation, here clockwise, the forming rollers 40 are set in rotation by the forming insert 50 via the frictional contact formed on the rolling section 52. The forming rollers 40 roll on the inner wall of the pipe. By inserting the conical expansion sections 45 at the free ends 42 of the forming rollers 40 into the pipe, the pipe is expanded to the diameter predetermined by the stabilizing sections 44.

[0047] Because the forming rollers 40 are arranged at an angle, an additional force component in the axial direction is created as the forming rollers 40 roll along the inside of the pipe, which directs the movement of the device 10 into the pipe and thus facilitates its movement. Consequently, the pipe can be easily and quickly expanded to the desired radius. The force component in the axial direction allows for easier removal of the device 10 from the expanded pipe when the direction of rotation is reversed, i.e., counterclockwise.

[0048] Fig. 5 shows, by way of example, a system for expanding a pipe using the device 10 described above and a set of additional forming inserts 70, 80, 90, 100, each with different diameters that differ from the forming insert 50. Pipes, in particular downpipes of rain gutters, have standardized diameters. Consequently, each pipe diameter is assigned a forming insert 50, so that the outer diameter, hence the sum of the diameters of the forming insert and the forming rollers 40, measured at the stabilizing section 44, is larger by a fixed amount than the diameter of the pipe to be expanded. Consequently, by this amount, two pipes that were originally of the same diameter can be connected to one another by expanding one end of a pipe.

[0049] The mold inserts can each be interchangeably attached to the device 10. The mold inserts with a diameter greater than 30 mm are made of plastic, while the mold insert 50 with a diameter smaller than 30 mm is made of metal. Depending on the diameter, the mold inserts have a different number of O-rings 53 to optimize the frictional contact between the mold insert 50 and the forming rollers 40.

[0050] The mold inserts with a diameter greater than 30 mm have three or four O-rings 53, while the mold insert 100 has seven O-rings 53.

[0051] To adjust the diameter of the device 10 for expanding a pipe, the screw 54 is loosened to remove the first mold insert 50. To make inserting the second mold insert particularly easy, the forming rollers 40 are also loosened and positioned on the outer edge of the device 10, see. Fig. 1 . After the second mold insert 70 has been inserted and secured by means of the screw 54, the forming rollers 40 are positioned to rest against the second mold insert 70 in order to ensure the transmission of force from the mold insert 50 to the forming rollers 40. Bezugszeichenliste

[0052] 10Device for expanding a pipe 20Drive shaft 30Receiving disc 32Receiving device 34Ball bearing 36Opening 38Guide groove 40Forming roller 41First end 42Second end 43Fastening section 44Stabilizing section 45Expanding section 46Axle element 47Roller element 48Fastening element 49Forming roller spring element 50First forming insert 51Wall section 52Rolling section 53O-ring 54Screw 55Groove 60Location bolt 62Protrusion 70Second mold insert 80Third mold insert 90Fourth mold insert 100Fifth mold insert DARotational axis of the drive shaft DFRotational axis of the forming roller AEMounting plane W1Angle between DA and DF W2Angle between mounting disc and mounting plane

Claims

1. Device (10) for expanding a pipe, comprising - a drive shaft (20), - a receiving disk (30) arranged on the drive shaft (20) and having a plurality of rail-like receptacles (32) extending from the inside to the outside, - a plurality of rotatably mounted forming rollers (40), wherein the forming rollers (40) each have a first end (41) arranged on one of the receptacles (32) and continuously adjustable in the receptacle (32) along the length of the receptacle (32) and a second, freely projecting end (42) and - a forming insert (50, 70, 80, 90, 100) which is detachably arranged between the forming rollers (40).

2. Device (10) according to claim 1, characterized in that the forming rollers (40) are mounted on the receiving disc (30) at an inclination such that when the receiving disc (30) rotates in one direction of rotation, the second end (42) of the forming rollers (40) leads the first end (41) in the direction of rotation.

3. Device (10) according to claim 1 or 2, characterized in that the receptacles (32) are formed obliquely to the receiving disc (30) such that an angle in the range of 84° to 89.5° in the tangential direction of the receiving disc (30) is formed between the axes of rotation (DA, DF) of the forming rollers (40) and the receiving disc (30).

4. Device (10) according to one of the preceding claims, characterized in that the forming rollers (40) are arranged in a circle around the axis of rotation of the drive shaft (20) on the receiving disc (30), wherein opposite forming rollers (40) are directed opposite to one another in the direction of rotation (DA) of the drive shaft (20).

5. Device (10) according to one of the preceding claims, characterized in thatthe forming rollers (40) each have a cylindrical fastening section (43) for arranging on the receptacles (32) and a conically shaped widening section (45), wherein the widening section (45) is tapered towards the second end (42) of the forming rollers (40).

6. Device (10) according to claim 5, characterized in that a cylindrical stabilizing section (44) is arranged between the widening section (45) and the fastening section (43), wherein the stabilizing section (44) has a larger diameter than the fastening section (43).

7. Device (10) according to one of the preceding claims, characterized in that the mold insert (50, 70, 80, 90, 100) has at least one rolling section (52) of enlarged diameter in contact with the mold rollers (40) for transmitting force between the mold insert (50, 70, 80, 90, 100) and the mold rollers (40).

8. Device (10) according to one of the preceding claims, characterized in that the receptacles (32) each have, on a first side of the receiving disc (30) facing the drive shaft (20), a guide groove (38) for radially adjustable reception (32) of a fastening element (43) of the forming roller (40), wherein a slot-shaped opening (36) extending through the receiving disc (30) runs along the guide groove (38).

9. Device (10) according to one of the preceding claims, characterized in that the drive shaft (20) is rotatably mounted relative to the receiving disc (30).

10. Device (10) according to one of the preceding claims, characterized in that the drive shaft (20) is non-rotatably coupled to the mold insert (50,70,80,90,100).

11. Device (10) according to one of the preceding claims, characterized in that a projection (62) arranged on the drive shaft (20) engages in an engagement opening (55) of the mold insert (50,70,80,90,100).

12. Device (10) according to one of the preceding claims, characterized in that the mold insert (50, 70, 80, 90, 100) is attached to a locating bolt (60) on the side of the locating disc (30) opposite the drive shaft (20).

13. Device (10) according to claim 12, characterized in that the drive shaft (20) and the locating bolt (60) are formed in one piece.

14. A system for expanding a pipe, comprising - a device for expanding a pipe (10) according to claim 1, - wherein the mold insert (50, 70, 80, 90, 100) is a first mold insert (50), - and a second mold insert (70), - wherein the first and second mold inserts (50, 70) are each interchangeably attachable to the device (10) and the first and second mold inserts (50, 70) have different diameters.

15. A method for adjusting the diameter of the device for expanding a pipe (10) according to claim 1, comprising the steps of: - removing a first mold insert (50), - inserting a second mold insert (70) and - positioning the mold rollers (40) to bear against the second mold insert (70).

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