WELDING DEVICE WITH NOZZLE APPARATUS FOR COOLING A WORKPIECE DURING THE WELDING PROCESS

Abstract

The invention relates to a welding device for welding at least one workpiece, comprising: a welding torch, which is designed to create an electric arc for welding the at least one workpiece; and a nozzle apparatus, which is arranged on the welding torch and has a cooling nozzle array, which has at least one row of cooling nozzles, wherein for cooling the workpiece, the respective cooling nozzle can be supplied with an adjustable volume flow of a cooling medium.

Claims

1. Welding device for welding at least one workpiece, comprising: a welding torch, which is designed to create an electric arc for welding the at least one workpiece; a nozzle apparatus, which is arranged on the welding torch and has a cooling nozzle array, wherein the cooling nozzle array has at least one radial row of cooling nozzles and at least two cooling nozzles are arranged in the row, wherein for cooling the workpiece, the respective cooling nozzle can be supplied with an adjustable volume flow of a cooling medium.

2. Welding device according to claim 1, wherein the cooling nozzles of the nozzle apparatus are arranged next to one another in a circumferential direction (U) of the welding torch, preferably equidistantly, so that the cooling nozzle array extends annularly around the welding torch.

3. Welding device according to claim 1, wherein the cooling nozzle array has a plurality of rows of cooling nozzles.

4. Welding device according to claim 1, wherein a plurality of cooling nozzles of the cooling nozzle array can be supplied with an adjustable volume flow of a particular cooling medium.

5. Welding device according to claim 1, wherein at least one cooling nozzle can be supplied with a first cooling medium and at least one further cooling nozzle can be supplied with a second cooling medium, wherein the second cooling medium differs from the first cooling medium in its composition.

6. Welding device according to claim 1, wherein the cooling nozzle array can be rotated about a rotational axis (R) so that the cooling nozzles can in particular be moved around the welding torch.

7. Welding device according to claim 6, wherein the welding device (1) is designed to adjust a rotation angle (W) of the cooling nozzle array with respect to the rotational axis (R) on the basis of a temperature signal and/or on the basis of an automatic calculation based on a known movement sequence of the welding torch during the welding process.

8. Welding device according to claim 1, wherein the cooling nozzle array can be tilted about a tilting axis (y), in particular a horizontal tilting axis.

9. Welding device according to claim 1, wherein the welding device has at least one temperature sensor that is configured to detect a temperature distribution of a workpiece produced by means of the welding device.

10. Welding device according to claim 9, wherein the welding device is designed to control, on the basis of the detected temperature distribution, a volume flow of a cooling medium dispensed through the respective cooling nozzle.

11. Welding device according to claim 1, wherein the respective cooling nozzle is fixed to the nozzle apparatus via a thread.

12. Welding device according to claim 1, wherein the welding device is designed to supply a cooling nozzle of the cooling nozzle array that is closer to the electric arc than a further cooling nozzle with a lower volume flow of a cooling medium than the further cooling nozzle in order to reduce the risk of interaction of the cooling medium with a process gas of the welding process.

13. Welding device according to claim 1, wherein the welding device is designed to dispense as cooling medium one of the following medium via at least one cooling nozzle: argon, helium, nitrogen, hydrogen, air, carbon dioxide, a mixture of a selection of the aforementioned gases.

14. A method for welding at least one workpiece, wherein the workpiece is constructed in layers by means of a welding device according to claim 1 and is cooled by means of the nozzle apparatus.

Description

[0042] Embodiments, further features and advantages of the present invention are explained below with reference to the figures. The figures show:

[0043] FIG. 1 a schematic representation of an embodiment of a welding device according to the invention in plan view during a welding process, wherein the welding torch changes direction by 90°,

[0044] FIG. 2 a schematic representation of an embodiment of a welding device according to the invention in plan view during a welding process, wherein the welding torch changes direction by 180°,

[0045] FIG. 3 a schematic side view of an embodiment of a welding device according to the invention with a cooling nozzle array which is rotatably mounted on the welding torch,

[0046] FIG. 4 a further schematic side view of the welding device shown in FIG. 3, and

[0047] FIG. 5 a schematic side view of a further embodiment of a welding device according to the invention.

[0048] FIGS. 1 and 2 show a schematic plan view of an embodiment of a welding device 1 according to the invention during a welding process, wherein the welding torch 2 changes direction by 90° (cf. FIG. 1) or 180° C. (cf. FIG. 2).

[0049] For performing the welding process, the welding device 1 according to FIGS. 1 and 2 has a welding torch 2 which is designed to create an electric arc so that, for example, a filler material or a surface of a workpiece to be manufactured can be melted in order, for example, to construct the workpiece layer by layer within the scope of a WAAM method.

[0050] In order to be able to cool the workpiece in a targeted manner during the welding process, the welding device 1 has a nozzle apparatus 20 which is arranged on the welding torch 2 and has a cooling nozzle array 21, which has at least one row 22 of cooling nozzles 23, wherein for cooling the workpiece, the respective cooling nozzle 23 can be supplied with an adjustable volume flow of a cooling medium 4.

[0051] The cooling nozzle array 21 according to FIGS. 1 and 2 can preferably be rotated about a rotational axis R so that the cooling nozzles 23 can in particular be moved around the welding torch 2. In FIGS. 1 and 2, the rotational axis is perpendicular to the plane of the sheet.

[0052] Thus, for example, when the welding torch 2 changes direction by 90°, as is shown in FIG. 1, the cooling position 230, i.e., the surface region 230 of the workpiece that is subjected to a cooling medium 4, can be adapted to the change in direction by rotating the cooling nozzle array about the rotational axis R, ideally such that in the movement direction B of the welding torch 2, the cooling position is behind the current weld pool which is created by means of the electric arc of the welding torch. FIG. 2 shows the adjustment of the cooling position 230 when the welding torch 2 changes direction by 180°.

[0053] The welding device 1 shown in FIGS. 1 and 2 can be embodied, for example, according to FIG. 3. In this case, the cooling nozzle array 21 has at least one row 22 of cooling nozzles 23, wherein the cooling nozzles 23 have different distances to the electric arc 3 of the welding torch. The cooling nozzle array 21 can be pivoted about a rotational axis R, wherein the rotation angle W can be adjusted by means of a suitable actuator which causes the rotation of the cooling nozzle array 21. In addition, the cooling nozzle array can be tilted or pivoted about a tilting axis y, in this case, for example, a horizontal tilting axis y. A particular cooling medium 4, with a variable volume flow in each case, can be dispensed through the individual cooling nozzles 23. Different cooling media 4, 40 can also be dispensed via the cooling nozzles 23. Furthermore, the rotation angle W of the cooling nozzle array 21 with respect to the rotational axis R and/or a tilting angle W′ with respect to the tilting axis y can be adjusted on the basis of a temperature signal, which may be provided, for example, by a temperature sensor 24. Furthermore, the temperature signal can be used to adjust the volume flows of the cooling medium/media 4, 40.

[0054] The cooling medium or media can each be one of the following cooling media: argon, helium, nitrogen, hydrogen, air, carbon dioxide, a mixture of a selection of the aforementioned gases.

[0055] As is furthermore shown in FIG. 4, the cooling nozzle array 21 of the welding device 1 according to FIG. 3 can have a plurality of rows 22 of cooling nozzles 23, wherein, for example, it is possible to orient the coolant flows 4 of the cooling nozzles of the outermost rows 22 inward in order to concentrate the cooling power onto the path traveled by the welding torch 2.

[0056] FIG. 5 shows a further embodiment of a welding device 1 according to the invention, wherein, in contrast to FIGS. 3 and 4, the cooling nozzles 23 are in this case arranged annularly around the welding torch 2 in a circumferential direction U of the welding torch 2, preferably equidistantly to one another, so that the cooling nozzle array 21 extends annularly around the welding torch 2.