Processing machine and method for working the end of a pipe

Abstract

A processing machine and method for planing an end surface of a finished pipe with a clamping device for the pipe to be processed via a tool holder with a planing tool, whereby the tool holder is driven by a motor and can rotate about an axis of rotation. The tool holder is driven by a motor so that it can rotate about an axis of rotation, whereby the clamping device and the tool holder are driven by a motor and can move toward one another in a direction parallel to the axis of rotation of the tool holder. The processing machine includes a cooling device that is arranged in such a manner that it cools the pipe to be processed and/or the planing tool with the aid of liquid and/or solid carbon dioxide during the operation of the device.

Claims

1. A processing machine for planing an end surface of a pipe comprising: a clamping device for the pipe to be processed; a tool holder with a planing tool, whereby the tool holder is driven by a motor and can rotate about an axis of rotation, and whereby the clamping device and the tool holder can be moved onto each other, driven by a motor, in a direction parallel to the axis of rotation of the tool holder; and a cooling device that is arranged in such a manner that it cools the pipe to be processed and/or the planing tool with the aid of a cooling medium consisting essentially of solid carbon dioxide dry ice snow during the operation of the device and without formation of an insulating gaseous layer, wherein the cooling device includes at least one nozzle and a reservoir for liquid carbon dioxide that is connected via a line to the nozzle, wherein the nozzle has an expansion chamber that is arranged in such a manner that liquid carbon dioxide supplied from the reservoir expands in the expansion chamber to produce the solid carbon dioxide dry ice snow, and wherein the nozzle is arranged in such a manner that during the operation of the device the solid carbon dioxide dry ice snow flows out of the nozzle in the vicinity of engagement between the pipe and the planing tool.

2. The processing machine according to claim 1, wherein the nozzle is arranged in such a manner that during the operation of the device the solid carbon dioxide dry ice snow flows out of the nozzle onto the pipe in the vicinity of the engagement between the pipe and the planing tool.

3. The processing machine according to claim 1, wherein the nozzle is arranged in such a manner that during the operation of the device the solid carbon dioxide dry ice snow flows out of the nozzle onto the planing tool in the vicinity of the engagement between the pipe and the planing tool.

4. The processing machine according to claim 1, wherein an end of the line is arranged in the nozzle in such a manner that the solid dry ice snow produced in the expansion chamber can be charged out of the nozzle with the aid of compressed air.

5. The processing machine according to claim 1, further comprising a stop for an end surface of the pipe to be processed.

6. The processing machine according to claim 5, wherein the stop is driven by a motor in a direction substantially vertical to the axis of rotation of the tool holder from a first position into a second position, the stop being arranged in the first position in such a manner that it is brought into engagement with the end surface of the pipe to be processed, and the stop being arranged in the second position in such a manner that it frees the end surface of the pipe to be processed.

7. The processing machine according to claim 1, further comprising a first clamping device for the pipe to be processed, a second clamping device for the pipe to be processed, a first tool holder with a parting-off tool and a second tool holder with a planing tool, whereby the first and the second tool holders are driven by a motor so that they can rotate about an axis of rotation, whereby at least the first or the second clamping device is driven by a motor in a direction parallel to the axis of rotation of the first and the second tool holder, whereby the first and the second tool holder are advanced driven by a motor in a direction vertical to the axis of rotation, the first and the second tool holders being arranged in such a manner that the tools received in the tool holders between the first and the second clamping device can be brought into engagement with the pipe to be processed.

8. A method for planing an end surface of a pipe comprising the steps of: clamping the pipe with a clamping device; rotating a planing tool about an axis of rotation coinciding with a symmetrical axis of the pipe to be processed; moving the pipe section and the planing tool relative to one another in a direction parallel to the axis of rotation toward one another; engaging the planing tool with an end surface of the pipe; planing the end surface of the pipe; and producing solid carbon dioxide dry ice snow by expansion of liquid carbon dioxide in an expansion chamber, wherein during the engagement between the planing tool and the end surface of the pipe, the pipe to be processed and/or the planing tool are cooled with a cooling medium consisting essentially of the solid carbon dioxide dry ice snow and without formation of an insulating gaseous layer.

9. The method according to claim 8, wherein the solid carbon dioxide dry ice snow produced by the expansion of liquid carbon dioxide in the expansion chamber is charged out of the nozzle with the aid of compressed air.

10. The method according to claim 8, wherein the process occurs without the supply of an additional lubricant to the planing step.

Description

(1) Other advantages, features and possibilities of application for the present invention become clear from the following description of an embodiment and from the associated figures.

(2) FIG. 1 shows a schematic lateral sectional view of an embodiment of the processing machine in accordance with the invention without a pipe taken up in it.

(3) FIG. 2 shows a schematic sectional view of the processing machine of FIG. 1 with a pipe taken up in it.

(4) FIG. 3 shows a schematic sectional view of the processing machine of FIGS. 1 and 2 with extended stop.

(5) FIG. 4 shows a schematic sectional view of the processing machine of FIGS. 1 to 3 with the planing tool engaged with the pipe.

(6) FIG. 5 shows a schematic sectional view of the processing machine of FIGS. 1 to 4 with retracted tool.

(7) FIG. 6 shows a schematic sectional view of the processing machine of FIGS. 1 to 4 with extension of the processed pipe.

(8) FIG. 7 shows a perspective view of an embodiment of the planing tool.

(9) In the figures identical reference numerals designate identical elements.

(10) FIG. 1 shows an embodiment of the processing machine 1 in accordance with the invention in a schematic lateral sectional view. The individual components of the machine 1 can be clearly recognized. The processing machine comprises a clamping cylinder 2 as clamping device for the pipe to be processed (not shown in FIG. 1). The clamping cylinder 2 grips the pipe on its outside circumference and exerts a force substantially in the radial direction of the pipe. Furthermore, the machine is provided with a tool holder 3 in which a planing tool 4 is received. The tool holder 3 is driven with the aid of a motor drive 5 in a rotatable manner about an axis of rotation 6 so that the planing tool 4 executes a rotary motion about the axis of rotation 6, whereby the radius on which the planing tool 4 moves corresponds approximately to the radius of the pipe to be processed and taken up in the clamping cylinder 2.

(11) The machine is arranged in such a manner that the pipe to be processed and taken up in the clamping cylinder 2 is arranged in such a manner that its axis of symmetry substantially coincides with the axis of rotation 6 of the tool holder 3.

(12) In order that a work plane of the machine is clearly defined, the machine furthermore comprises a stop 7 that is driven by a motor, in this case by a linear drive 8 in a direction 9 substantially vertical to the axis of rotation 6 and that can be moved out of the advance track of the tool holder 3.

(13) Furthermore, the tool holder 3 can be moved by a linear drive 10 in a direction substantially parallel to the axis of rotation 6 so that the planing tool 4 can be advanced to the pipe to be processed and moved back again.

(14) The nozzle 11 provided on the machine as component of a cooling device for cooling the work piece to be processed, i.e. the pipe, during the engagement between the planing tool 4 and the pipe 14 is decisive for the improvement in accordance with the invention of such a processing machine for planing an end surface of a pipe.

(15) To this end the nozzle 11 is also connected to a device for producing compressed air via lines 12 and to a reservoir for liquid carbon dioxide. The nozzle 11 is arranged in such a manner that the liquid carbon dioxide from the reservoir can expand in an expansion chamber of the nozzle 11 and in this manner dry ice particles, also designated here as dry ice snow, are produced. This dry ice snow subsequently passes into the air current produced by the compressed air and is beamed at a high speed onto the surfaces to be cooled of the pipe to be processed and of the planing tool 4. Due to its solid aggregate state the dry ice snow does not form an insulating gaseous layer between the snow and the surfaces to be cooled, so that an effective cooling of the surfaces is brought about.

(16) FIGS. 2 to 6 show the device during the turning and planing of the end surface 13 of an already parted-off, i.e. cut-to-length pipe 14. The pipe is moved in FIG. 2 into the clamping cylinder 2 of the processing machine 1 and comes to rest on stop 7. At this point in time of the machining procedure the stop 7 is moved radially with the aid of its motor drive 8 into the machine 1 so far that it extends at least sectionally along the end surface 13 of the pipe 14.

(17) In the next step the clamping cylinder 2 is advanced so that the pipe 14 is clamped in the clamping cylinder 2 for the machining procedure. FIG. 3 now shows how the stop 7 is subsequently moved by the motor drive 8 out of the range of the end surface 13 of the pipe 14. The actual procedure of the planing or planing milling of the end surface 13 of the pipe 14 now begins, as is schematically shown in FIG. 4. To this end is the tool holder or more precisely the planing tool 4 received on it driven by the motor 5 so that it is rotated about the axis of rotation 6 and at the same time is advanced with the aid of the linear drive 10 in the direction towards the end surface 13 of the pipe 14 so that the planing tool 4 mills off the end surface 13 in the circumferential direction of the pipe 14.

(18) At the same time dry ice snow is blown via the nozzle 11 into the area of the engagement between tool 4 and workpiece 14.

(19) When the actual milling of the end surface 13 is ended, the tool 4 is retracted with the tool holder 3 as shown in FIG. 15 and the finished milled and planed pipe 14 is subsequently moved out as is indicated in FIG. 6 after the opening of the clamping cylinder 2.

(20) FIG. 7 shows an embodiment of the planing tool 4 received in the tool holder 3. The planing tool 4 is an indexable cutting insert with two cutting edges 27, 28. This indexable cutting insert can be used for the machining of the pipe ends of two pipe sections. During operation the cutting insert 4 is received in such a manner on the tool holder that the first cutting edge 27 can process the pipe end of a previously parted-off pipe section. In order to receive the cutting insert 4 on the tool holder 3 the tool 4 comprises a central fastening hole 29. Furthermore, the cutting insert 4 comprises a lower surface or bottom surface 30 that serves as a contact surface on the tool holder 3 and comprises side surfaces 31, 32 that connect the lower surface 30 to an upper surface 33. The upper surface 33 is designed concavely in the embodiment shown. The cutting insert 4 can be received on the tool holder 3 in such a manner that during the machining of the pipe ends the upper surface 33 serves as a chip surface on which the chips run off.

(21) It is pointed out for purposes of the original disclosure that all features that result for a person skilled in the art from the present specification, the drawings and the claims, even if they were described concretely only in conjunction with certain other features, can be combined individually as well as in any combinations with other features or groups of features disclosed here in as far as this was not expressly excluded or unless technical facts render such combinations impossible or meaningless. For the sake of brevity and the legibility of the specification the comprehensive, explicit presentation of all conceivable combinations of features is not given here.

(22) Whereas the invention was presented and described in detail in the drawings and the preceding specification, this presentation and specification are only by way of example and are not intended to be a limitation of the protective scope as it is defined by the claims. The invention is not limited to the disclosed embodiments.

(23) Modifications of the disclosed embodiments are obvious to the person skilled in the art from the drawings, the specification and the attached claims. In the claims the word comprise does not exclude other elements or steps and the indefinite article a does not exclude a plurality. The mere fact that certain features are claimed in different claims does not exclude their combination. Reference numerals in the claims are not intended to be a limitation of the protective scope.

LIST OF REFERENCE NUMERALS

(24) 1 processing machine, machine 2 clamping cylinder 3 tool holder 4 planing tool 5 drive 6 axis of rotation 7 stop 8, 10 linear drive 9 direction 11 nozzle 12 line 13 end surface of pipe 14 14 pipe 27, 28 cutting edge 29 fastening hole 30 bottom surface 31, 32 side surface 33 chip surface