The invention relates to a device for compressing a tube according to the preamble of patent claim 1 and a method according to the preamble of patent claim 9.
State of the art
The 1 describes a device 100 for upsetting a tube according to the prior art. A pipe 400 is by means of a clamping device 500 so absorbed and taut that a first part length 411 of the pipe 400 one-sided from the clamping device 500 protrudes. The device 100 for upsetting the protruding first part length 411 of the pipe 400 comprises a first receiving device 210 with a tubular receiving space 213 for receiving the free end of the tube 400 over the first part length 411 , wherein the receiving space is open at its end facing the clamping device and an at least partially circumferential profile groove 215 has and at its opposite end by a stop 222 for the free end of the pipe 400 is completed. After starting the device 100 against the tensioning device 500 and recording the first part length 411 of the pipe 400 in the tubular receiving space 213 becomes the device 100 with a force F against a pressure piece 200 applied. The first recording device 210 and the pressure piece 200 can be formed in one piece or multiple parts. The applied force F moves the device 100 with the stop 222 against the first part length 411 of the pipe 400 and leads to further application of force to deformation or compression of the first part length 411 , The material of the first part length flows 411 of the pipe 400 in the profile groove 215 ,
Disadvantage of this device and this method is that between the profile and the clamping device in a front, directed to the profile groove portion of the clamped tube due to the flow of the material during deformation, in the clamping area, an increased contact pressure between the outer surface of the clamped part of the tube and the tensioning device is constructed, depending on the pipe material, for. B. especially stainless steels, leads to a cold welding of the tube with the adjacent support surface in the clamping area. This cold welding creates problems in separating the tube from the fixture after the upsetting process, which in most cases results in an interruption of the manufacturing process. In addition, according to the prior art, only pipes with a continuous cylindrical cross-sectional profile without sequential diameter increases can be accommodated.
The DE 34 43 217 A1
describes a press for chipless forming an end of rod-shaped workpieces, in particular pipes of metal, wherein the workpiece end between the pressing tool and the mold is plastically deformed and is widened by a Aufweitungspressformkörper at its end to be deformed.
The publication US 5 904 063 A
describes a crimping tool as a receptacle and support member for a pipe, wherein the crimping tool is mounted in a cylindrical bore of a receptacle and is tightened with a screw.
Description of the invention
Based on this prior art with its disadvantages, the invention has the object, a known device and a known method for upsetting a tube in such a way that the production times are reduced, the repair and maintenance costs are reduced and the service life of the device can be increased to perform the process of compression and forming faster, safer and thus more economical.
This object is achieved by the features of the device claim 1. The device according to the invention is particularly characterized in that between the support jaws at least a second compression spring element is arranged in the circumferential direction, for spreading the support jaws. With this additionally acting pressure force of the compression spring elements between the support jaws, a further force component for separating and opening the support jaws is present, which substantially favors the loosening of the support jaws of the deformed pipe section and automated.
It is further claimed in claim 1 that the support element is formed from at least two circumferentially distributed and radially opening support jaws formed. This advantageous division of the support element allows a direct independent opening of the jaws against each other. As soon as the applied force is withdrawn after the upsetting process and the compression spring elements press the support jaws on the inclined plane in the direction of the clamping device in the axial direction, this simultaneously ensures a rapid opening of the support jaws.
In addition, claimed in claim 1, a second receiving device, in which a first receiving device is axially displaceably mounted, and a support element, which at the end of the second receiving device associated with a clamping device between an open position and a support position is mounted radially expandable and compressible, for positively enclosing and supporting the tube in the support position via a second protruding part of the length of the tube between the tensioning device and the first receiving device. Advantage of this arrangement according to the invention of a multi-part device for compressing and deforming a tube is the self-displaceable and opening arrangement of the individual device components, which makes it possible that after upsetting and deformation process, a support region of the device between a profile and the jig from a support Automatically automatically widens its position into an open position and releases the tube for removal. The cold welding described above is counteracted or by the radial process of the support element or of its support jaws, the decoupling of the device is facilitated by the Roher after upsetting. This leads to significantly lower production times, as well as a significant reduction in wear of the tools while saving on repair and maintenance costs. The multi-part opening support element also allows the inclusion of pipe sections with sequential diameter or profile increases.
In a first embodiment, the invention provides that the support element is additionally mounted so as to be axially displaceable on the second receiving device, for positively enclosing the tube over its second partial length. This axial and radial movement component of the support element favors the release of the support element from the second protruding part length of the tube.
Furthermore, the invention provides that the second receiving device at its end facing the clamping device has a conical widening, which increasingly opens in the direction of the clamping device, and that the support element is mounted not only radially but also axially displaceable on the conical widening. This results in a significant advantage in the separation of the clamping device of the deformed pipe end in the way that the wedge effect of the conical widening the axial and radial displacement force of the support element is supported and thus also the separation force of the clamping device is reinforced by the pipe section.
Incidentally, it is provided that, for the axial displacement of the support element in the open position, at least one first compression spring element between the second receiving device and the support element is arranged parallel to the longitudinal axis of the device. These compression spring elements additionally support the o. G. necessary displacement force to expand the support member in the axial direction and support the opening of the support element.
A further embodiment of the invention provides that the second receiving device has a first stop for the support element in the open position and a second stop for the support element in the support position. This ensures that the support element assumes the optimum support position and securely encloses the tube when immersed, thus avoiding undesired deformations on the protruding tube end during the upsetting process.
In a further embodiment of the invention, it is provided that an end of the first receiving device facing away from the clamping device has a radially extending pressure piece firmly connected to the first receiving device with a stop for the second receiving device and a third compression spring element, which is located between the stop of the pressure piece and a third stop of the second receiving device is arranged. The advantage is the automated decoupling of the first receiving device from the first protruding part of the length of the tube.
It is further provided that the tubular receiving space is bounded inwardly by a mandrel as part of the first receiving device. The mandrel is used for centering the first receiving device with respect to the projecting pipe section and favors, in particular, that the introduced compressive force is introduced uniformly to the pipe section and the pipe does not break at an undesired location.
In a further embodiment it is provided that the support mandrel is removably mounted in the first receiving device. An advantage is that the device by the interchangeable mandrel quickly and easily to other dimensions, such. B. larger thicknesses of the pipe material, or other internal profiles, such. B. oval or polygonal, the tube can be tuned and that in the event of an accident, z. As the breakage of the mandrel or even if the mandrel is no longer dimensionally stable due to wear, it can be replaced quickly.
The above object is further achieved by a method according to claim 9 for upsetting a tube by means of a device. The claimed method comprises the following steps:
- Clamping the tube in a stationary clamping device such that a first partial length of the tube protrudes from the clamping device,
- Sliding the first receiving device on the free end of the projecting tube so, that the tube is taken with its first part length of the tubular receiving space and
- - And acting on the first receiving device at its end facing away from the clamping device with an axially directed to the central axis of the tube and in the direction of tensioning device F so that the tube is upsetting and deformed to form an at least partially extending federal in the profile.
The method according to the invention is characterized in that, by applying the first receiving device with the axial force F, the support element is initially moved radially into a supporting position in which it encloses the tube in a form-fitting manner over a second projecting partial length between the clamping device and the first receiving device and supports, before then the tube is compressed and deformed to form the Federal in the profile groove. The particular advantage of the method is the gradual supply of the split executed device to the pipe section to be deformed, the tightening of the individual portions of the pipe section as a follow-up process during the employment of the device and during the upsetting process. This method allows for the automatic transfer of the support elements with respect to the second protruding part length of the pipe from a support position to an open position and the automatic release of a possible cold fouling at the second part length of the pipe. The resulting advantages have already been described above with reference to the device according to the invention.
Further advantages and details of the invention will become apparent from the dependent claims of the method and from the following description in which the embodiments of the invention shown in the figures are explained in more detail. In addition to the listed combinations of features, features alone or in other combinations are essential to the invention.
Description of the figures
1 Apparatus for upsetting pipe according to the prior art
2 Apparatus for upsetting pipe in an open position according to the invention; and
3 Device for upsetting pipe in a support position according to the invention
The invention will be described below with reference to FIGS 2 and 3 described in detail:
The 2 describes a device 100 for upsetting a pipe 400 in an open position, comprising: a tensioning device 500 for tightening the pipe 400 so that the pipe 400 with a first part length 411 and a second partial length 412 survives and a first recording device 210 with a tubular receiving space 213 , for receiving the free end of the pipe 400 over the first part length 411 , This is the recording room 213 at its the tensioning device 500 facing the end open and has at least partially a circumferential radially outwardly extending profile groove 215 on. At the to the tensioning device 500 opposite end is the recording room 213 through a stop 222 for the free end of the pipe 400 limited. Furthermore, the device describes 100 a second receiving device 230 in which the first recording device 210 is mounted axially displaceable. A support element 300 , which at the tensioning device 500 associated end of the second receiving device 230 is radially expandable and compressible between an open position and a support position, serves the positive enclosing and supporting the tube 400 in the support position over the second protruding part length 412 of the pipe 400 between the tensioning device 500 and the first receiving device 210 , The second recording device 230 is at her jig 500 facing end formed with a conical widening, which extends in the direction of the clamping device 500 increasingly opens, and the support element 300 is on the conical expansion not only radially, but also axially displaceable superimposed. In an embodiment, not shown, the conical guide surface 232 also be arcuate or stepped. Even a self-telescopically interlocking arrangement of the support jaws of the support element for clamping the protruding second part length 412 of the pipe 400 is conceivable. For axial displacement of the support element 300 in the open position is between the second receiving device 230 and the support element 300 parallel to the longitudinal axis of the device 100 in a corresponding recess within the second receiving device 230 at least one first compression spring element 316 arranged.
The second recording device 230 shows a first stop 235 for the support element 300 in the open position and a second stop 236 for the support element 300 in the support position.
At the tensioning device 500 remote end of the first receiving device 210 extends radially in with the first receiving device 210 firmly connected pressure piece 200 with a stop 201 for the second recording device 230 , In this case, the pressure piece 200 With the second receiving device 230 be formed in one or more parts, however, there must always be a frictional connection. Between the stop 201 of the pressure piece 200 and a third stop 231 the second receiving device 230 is a third compression spring element 240 arranged. The tubular receiving space 213 the first receiving device 210 gets inward through a mandrel 220 as part of the first recording device 210 limited. The mandrel 220 is here as a replacement part in the first receiving device 210 fastened by means of a transition fit or a press fit and with a connecting element, such. B. a spring pin or a grub screw against twisting and releasing secured.
The 3 describes the device 100 after the upsetting process. The support elements 300 are still closed in the support position and take the second section 412 of the pipe 400 positive locking. By acting in this support position effective maximum force F on the pressure surface 202 of the pressure piece 200 are the compression spring elements 240 . 315 . 316 compressed and act with their respective compressive force against the force F to the bearing surfaces of the respective stops 201 . 231 . 233 . 212 , In the profile groove 215 is the deformed area of the pipe 400 seen.
a. Tensioning and deforming
A pipe 400 gets into a tensioning device 500 inserted and tightened, with a protruding from the jig first part length 411 , Against this protruding part length 411 becomes a device 100 for upsetting this partial length 411 arranged. The next step is the device 100 with a first receiving device 210 and a pressure piece 200 almost powerless in the direction of the clamping device 500 Hired until the support surface 302 a support element 300 on a stop surface 510 the tensioning device 500 is applied. Here is the support element 300 from at least two supporting jaws 310 built up. In this position, the support jaws are 310 of the support element 300 in an open position over a second partial length 412 of the pipe 400 open, see also 2 , The first protruding part length 411 of the pipe 400 is in a tubular receiving space 213 between the first receiving device 210 and a mandrel 220 centered. A fifth stop 222 within the receiving space limits the Aufschiebeposition the device 100 to the protruding first part length 411 , The mandrel 220 is within the first recording device 210 arranged and supports the first part length 411 and a second 412 Part length of the pipe 400 over the inner surface of the pipe 400 from. In the further course of the compression process, the device 100 acted upon by a force F acting on a face 202 a pressure piece 200 the first receiving device 210 in the axial direction to the pipe 400 acts. This pushes the device 100 continue in the direction of the tensioning device 500 together. Assigned compression spring elements 315 between the support element 300 and the first receiving device 210 and compression spring elements 316 between the at least two support jaws 310 of the support element 300 and a compression spring element 240 between the pressure piece 200 and a second receiving device 230 are compressed and thus stretched. The support jaws 310 be over a conical guide surface 232 the second receiving device 230 shifted against the direction of force. This close the jaws 310 in the radial direction to the second part length 412 of the pipe 400 and enclose this form-fitting. Another application of force leads to compression and deformation of the projecting part length 411 and 412 , where material of the pipe 400 in the profile groove 215 flows.
b. Loosen and remove the device
After the upsetting process is completed, the previously applied force F is withdrawn. All compression spring elements 315 . 316 . 240 relax. The resulting pressure forces lead to the automatic opening of the device 100 and in particular the support jaws 310 , whereby the deformed part length 411 . 412 of the pipe 400 is released. The compression spring element 240 between the pressure piece 200 the first receiving device 210 and the second receiving device 230 automatically pushes the mandrel out of the interior of the projecting part length 411 . 412 of the pipe 400 out. At the same time push the compression spring elements 315 the support jaws on the conical guide surface in an open position (see 2 ). The arranged between the support jaws compression spring elements 316 cause a radial opening of the support jaws 310 ,
LIST OF REFERENCE NUMBERS
- Pressure piece
- Stop / pressure piece
- first receiving device
- Stop surface of the first receiving device
- tubular receiving space
- profile groove
- fifth stop
- second receiving device
- third stop
- Guide surface / Record
- sixth stop
- first stop
- second stop
- head face
- third compression spring element
- support element
- support surface
- supporting jaws
- Guide surface / support element
- Abutment surface / support element
- first compression spring element
- second compression spring element
- first part length
- second part length
- Abutment surface / tensioning device