Installation of pressure hull penetrations in the pressure hull of a submarine

Abstract

The present invention relates to a welding robot 20 for inserting a pressure body feedthrough 70 into a pressure body 10, wherein the welding robot 20 has a frame 30 with at least three feet 40, wherein the feet 40 are designed for placement on the pressure body 10, wherein the welding robot 20 has a multi-axis arm 50, wherein the welding robot 20 has a plasma cutting head and a welding head, and wherein the welding robot 20 has a gripping device for a pressure body feeder.

Description

[0001] The invention relates to a method and a device for introducing pressure body penetrations into a pressure body.

[0002] A submarine has a pressure hull to maintain a survivable pressure inside for the crew. The pressure hull must therefore withstand the external pressure. However, various connections must be provided between the interior of the pressure hull and the exterior, such as the propeller shaft, a periscope, as well as airlocks or hatches for the crew, and a gun barrel. Furthermore, connections must be made to systems like sonar, fuel tanks, and the like. As a result, the pressure hull ultimately has a relatively large number of pressure hull penetrations, each of which is particularly critical, as any failure of one could potentially lead to water ingress.Furthermore, the components used as pressure vessel penetrations in a pressure vessel are sometimes comparatively large and correspondingly heavy, so they are currently welded to the pressure vessel using auxiliary structures to hold them securely in position for the actual welding process. Additional steps are required to prepare the resulting recess, in particular to chamfer it to create volume for the welding material.

[0003] A particular challenge arises from the fact that while the exterior of the pressure hull is easily accessible, a pressure hull typically contains internal frames. These frames can deviate from their positions specified in the plans due to manufacturing processes. Since the installation of a pressure hull penetration must be relative to the actual positions of the frames, it is necessary to establish a relative reference system between the interior and exterior of the pressure hull.

[0004] A further complicating factor is the high integration density inside a submarine. This makes installation even more difficult, especially if other components are already present inside the pressure hull. Simply due to space constraints, creating the necessary openings from the inside to the outside can also be challenging.

[0005] The object of the invention is to provide a method for the safe and efficient insertion of pressure vessel penetrations.

[0006] This problem is solved by the method with the features specified in claim 1 and by the multifunctional welding robot with the features specified in claim 12. Advantageous further developments are described in the dependent claims, the following description, and the drawings.

[0007] The method according to the invention serves to introduce a pressure hull penetration into a pressure hull. For the purposes of this invention, "pressure hull" also refers to components of a pressure hull. A submarine is typically manufactured section by section, i.e., from individual cylindrical pieces that are later welded together to form a pressure hull. These segments of the pressure hull are already considered pressure hulls within the meaning of the invention, since they will ultimately be part of the pressure hull. The method comprises the following steps: a) Providing a pressure vessel, b) Applying position markers to the outside, c) Setting up a welding robot on the outside of the pressure body, wherein the welding robot also has a plasma welding head and component placement fixtures. d) Optical detection of the position markings by the welding robot, e) Determining the exact position of the welding robot in relation to the pressure body from the recorded position of the position markers, f) Creating the recess with the plasma welding head, g) Removal of the welding robot.

[0008] The application of position markers in step b) serves to ensure reliable alignment on the outside of the pressure vessel. These markers are therefore preferably placed at predetermined positions on the pressure vessel, as this avoids the need for subsequent precise determination of the position. Firstly, the pressure vessel is typically a metal cylinder, so there is no external orientation available. Secondly, there are internal frames whose positions can only be precisely measured after manufacturing. Therefore, it is necessary to establish a reference system on the outside of the pressure vessel. This is most easily achieved using position markers at predetermined locations. For example, a position marker can be placed on the first frame of each section of the pressure vessel. Advantageously, several position markers can be placed at the same length and circumference.By attaching and measuring several, advantageously at least three, preferably four, position markings, the surface of the pressure body and its orientation can be determined.

[0009] The use of a welding robot enables flexible deployment within the manufacturing process. Previously, the cutouts were made using special fixtures, requiring the pressure bodies to be transported to these fixtures. This allows for greater flexibility in workflows. Since the welding robot is placed on the outside of the pressure body, it rests solely on the pressure body, thus requiring no additional space. This further enhances its versatility. The welding robot is preferably a welding robot according to the invention.

[0010] The welding robot according to the invention consists of a support structure, a multi-jointed arm, and tools attachable to the multi-jointed arm, in particular a plasma welding head. Other tools can also be attached to the multi-jointed arm, enabling it, for example, to grip and hold a component, such as a pressure vessel bushing. Although the welding robot cannot weld at this moment, it is nevertheless considered a welding robot within the meaning of the invention.

[0011] Since the welding robot can only be set up with a certain degree of accuracy, subsequent calibration by recording the position markers is advisable, as this easily achieves the necessary accuracy. This is done in step d). The exact position of the welding robot is then determined in step e) from the data recorded in step d). Therefore, it is sufficient to position the welding robot with a lower degree of accuracy than is required for the actual installation work.

[0012] The recess is created in step f) by using the plasma welding head, or plasma cutting head, to cut through the pressure body in such a way that a recess, a hole in the pressure body, is formed. The recess is preferably slightly larger than the pressure body penetration that will be installed in the recess in the following steps. The recess has, for example, V-shaped chamfers on its edges. These V-shaped chamfers mean that the edge of the recess tapers from the top towards the center of the material and then widens again towards the bottom. This creates a V-shaped space between the pressure body and the penetration on both the outside and inside, which can be filled with material during the subsequent welding process, thus ensuring a strong and stable weld.This is easily achieved through the use of a welding robot, thus reducing the need for subsequent grinding.

[0013] The welding robot can then simply be removed and used elsewhere.

[0014] In a further embodiment of the invention, the method additionally comprises the following steps between step e) and step f): h) Marking the recess to be created on the pressure vessel for the penetration using the plasma welding head, i) Checking the marking,

[0015] The marking in step h) is done by the plasma welding head at low power, so that while a mark is made, it can still be corrected in case of an error. The major advantage is that by using the same tool for both the marking and the recess itself, a high degree of accuracy is achieved, ensuring that step f) is performed exactly at the point of the marking.

[0016] Step i) is preferably performed manually, so the positional accuracy can be checked and documented according to current standardized processes. Step f) may be performed using further predetermined positions on the print body.

[0017] In a further embodiment of the invention, the method additionally comprises the following steps between step f) and step g): j) Provision of a pressure vessel penetration, k) Inserting the pressure body penetration into the recess and holding the pressure body penetration by the welding robot, l) Welding the pressure vessel penetration to the pressure vessel from the inside, m) Welding the pressure vessel penetration to the pressure vessel from the outside by the welding robot,

[0018] Inserting the pressure vessel bushing into the recess and holding it in place by the welding robot in step k) eliminates the need for preliminary welding and corresponding auxiliary elements, as the welding robot can hold the pressure vessel bushing securely and stably in position until welding, preferably from the inside, has been performed in step i), creating a load-bearing connection. The welding robot can then release the pressure vessel bushing and preferably weld the outside in step m). In this step i), the welding can initially be spot-welded to create a load-bearing connection and then completed in a second step, or the complete welding can be performed immediately.

[0019] In a further embodiment of the invention, the setup in step c) is carried out using augmented reality. The use of augmented reality, for example, glasses that display both the real world and a virtual one—in this case, for example, the target position of the welding robot or a display of any deviation from it—enables sufficiently accurate placement of the welding robot on the pressure vessel in a simple manner. Especially in complex production environments such as submarine construction, complete automation is often difficult to implement. At the same time, however, automatic support for the operator is very helpful, particularly for quickly achieving sufficiently accurate positioning.Advantageously, additional analog displays, such as a spirit level with crosshairs, a spirit level and similar auxiliary displays, can be attached to the support structure of the welding robot, which, for example, help to carry out the positioning if the glasses fail.

[0020] In a further embodiment of the invention, optical detection in step d) is carried out using at least one camera integrated into the welding robot. The camera can also be movably mounted on the robot arm, allowing the robot itself to control different camera positions in order to detect position markers at various locations. Alternatively, the welding robot can also be equipped with multiple cameras. Preferably, the cameras are suspended from the support structure of the welding robot and are not physically attached to the multi-jointed arm of the welding robot. This saves process time.

[0021] In a further embodiment of the invention, the marking in step h) is carried out with significantly less energy than the creation of the recess in step f). The use of the same tool, only with different energy, results in a very high positional reproducibility between marking and creation, meaning that the recess is actually created exactly where the marking has already been made.

[0022] In a further embodiment of the invention, the recess is created in step f) at at least two angles to widen the recess on both the top and bottom surfaces of the pressure body. This creates a volume to accommodate the material introduced during welding. Machine production using a welding robot allows for such precise results that post-processing, such as grinding, is unnecessary, unlike with a manually produced recess. Minimal manual finishing may still be required, for example, to remove the oxide layer or to add a missing ridge to the recess. However, this finishing is minimal compared to previous manual work.

[0023] In a further embodiment of the invention, the insertion in step k) is controlled manually. The advantage is that in the comparatively highly complex environment, complete automation is difficult to implement, so manual control is advantageous. On the other hand, the welding robot bears the weight, so there is no physical problem for the operator.

[0024] In a further embodiment of the invention, the insertion in step k) is carried out using augmented reality. Just as with the setup in step c), augmented reality, for example with the aid of appropriate glasses, can simplify the guidance to the predetermined location and support the achievement of the necessary accuracy.

[0025] In a further embodiment of the invention, an extraction system, preferably located on the bulkheads of the pressure body, is arranged inside the pressure body before the recess is created in step f). The bulkheads are particularly well suited for attaching, for example, such an extraction system; the extraction system completely removes any gaseous welding and plasma cutting products that arise and reliably prevents damage to other components inside the pressure body.

[0026] In a further embodiment of the invention, steps h) to m) are repeated. Thus, at one installation position of the welding robot, two or more pressure body penetrations are introduced into the pressure body. This can be useful, for example, in the area of ​​fuel tanks, particularly hydrogen storage tanks, or in the area of ​​sonar antennas.

[0027] In another aspect, the invention relates to a welding robot for inserting a pressure body penetration into a pressure body. The welding robot has a frame with at least three feet. The frame serves to absorb and transmit all occurring forces. The feet are designed for placement on the pressure body. The welding robot is thus placed directly on the pressure body. This must be taken into account with regard to the feet, since the pressure body is tubular, i.e., has a curved surface without flat surfaces. All forces are transmitted from the frame to the pressure body via the feet. The welding robot has a multi-axis arm. Such arms are common for robots today and allow, on the one hand, precise control of a tool connected to the multi-axis arm and its orientation in space, which enables, in particular, very precise cuts with extremely cleanly defined cut surfaces.Simultaneously, a multi-axis arm is also capable of holding and moving larger components, such as a pressure vessel bushing, and precisely aligning and holding them in an exact position. The welding robot is equipped with a plasma welding head. This head can be used to mark the workpiece in step h), create a recess in step f), and weld the pressure vessel bushing in step m). Furthermore, the welding robot has a gripper for feeding the pressure vessel. This allows the welding robot to position and hold the pressure vessel bushing in steps k and i).

[0028] In a further embodiment of the invention, the feet of the welding robot have a suction device for attachment to the pressure body. The suction device enables secure positioning on the round pressure body in a simple manner, reliably preventing slippage.

[0029] In a further embodiment of the invention, the plasma cutting head, the welding head, preferably a plasma welding head, and the gripping device can be interchangeably connected to the multi-axis arm.

[0030] In a further embodiment of the invention, the welding robot has at least one camera. The camera can, for example, be interchangeably connected to the multi-axis arm. Alternatively, preferably at least two, and more preferably four, cameras can be fixedly arranged on the frame.

[0031] In another embodiment of the invention, the welding robot has four feet. Four feet are advantageous due to their round cross-section, even though, unlike with only three feet, height adjustment may be necessary on uneven surfaces.

[0032] In a further embodiment of the invention, the welding robot has a rectangular base shape. In particular, the frame of the welding robot has a rectangular base shape.

[0033] The method according to the invention is explained in more detail below with reference to an embodiment shown in the drawings. Fig. 1 Device Fig. 2 pressure bodies Fig. 3 Exclusion Fig. 4 Pressure vessel penetration Fig. 5. Welding from the inside Fig. 6 Welding of inside and outside

[0034] The illustrations are highly schematic and not to scale, and serve only to illustrate the process description.

[0035] In Fig. Figure 1 shows how the welding robot 20 is positioned on a (partially) shown section of a pressure body 10. The welding robot 20 has a frame 30 with four feet 40 and can thus be ideally positioned on the round pressure body 10. The welding robot 20 has a multi-axis arm 50.

[0036] In Fig. 2 to Fig. Figure 6 shows the procedure on a section of the pressure body 10 in cross-section, as it is in Fig. 2 is shown. First, as in Fig. Figure 3 shows a recess 60° being created, with the plasma welding head held at two different angles, resulting in a V-shaped profile. Next, as shown in Fig. As shown in Figure 4, a pressure body feedthrough 70 is inserted into the recess 60 and held in position by the multi-axis arm 50 of the welding robot 20. First, manual welding from the inside is performed to create the [unclear text]. Fig. 5 weld seam 80 shown. Subsequently, the welding robot 20 can release the pressure body penetration 70 and the in Fig. Set the outer weld shown at 80°.

[0037] Reference sign 10 pressure bodies 20 welding robots 30 frames 40 feet 50 Multi-axis arm 60 Exclusion 70 Pressure vessel penetration 80 weld seam

Claims

[1] Method for introducing a pressure vessel penetration (70) into a pressure vessel (10), the method comprising the following steps: a) Providing a pressure vessel (10), b) Applying position markers to the outside, c) Setting up a welding robot (20) on the outside of the pressure body (10), wherein the welding robot (20) has a plasma welding head, d) Optical detection of the position markings by the welding robot (20), e) Determining the exact position of the welding robot in relation to the pressure body from the recorded position of the position markers, f) Creating the recess (60) with the plasma welding head, g) Removal of the welding robot (20). [2] Method according to claim 1, characterized by , that the procedure additionally includes the following steps between step e) and step f): h) Marking the recess (60) to be created for the pressure body penetration (70) on the pressure body (10) using the plasma welding head, i) Checking the marking. [3] Method according to any of the preceding claims, characterized by , that the procedure additionally includes the following steps between step f) and step g): j) Provide a pressure vessel penetration (70), k) Inserting the pressure body feedthrough (70) into the recess (60) and holding the pressure body feedthrough (70) by the welding robot (20), I) Welding the pressure vessel penetration (70) to the pressure vessel (10) from the inside, m) Welding the pressure body penetration (70) to the pressure body (10) from the outside by the welding robot (20). [4] Method according to any of the preceding claims, characterized by , that the setup in step c) is done using augmented reality. [5] Method according to any of the foregoing claims, characterized by , that the optical detection in step d) is carried out using at least one camera integrated into the welding robot (20). [6] Method according to any of the foregoing claims, characterized by , that the marking in step h) is carried out with significantly less energy than the creation of the recess (60) in step f). [7] Method according to any of the foregoing claims, characterized by , that the creation of the recess (60) in step f) is carried out at at least two angles in order to create a widening of the recess (60) on the top and bottom of the pressure body (10). [8] Method according to any of the foregoing claims, characterized by , that the insertion in step k) is controlled manually. [9] Method according to claim 8, characterized by , that the input in step k) is done using augmented reality. [10] Method according to any of the preceding claims, characterized by , that before the creation of the recess (60) in step f) inside the pressure body (10) an extraction system is arranged, preferably on the frames of the pressure body (10). [11] Method according to any of the foregoing claims, characterized by , that steps h) to m) are repeated. [12] Welding robot (20) for inserting a pressure body feedthrough (70) into a pressure body (10), wherein the welding robot (20) has a frame (30) with at least three feet (40), wherein the feet (40) are designed for placement on the pressure body (10), wherein the welding robot (20) has a multi-axis arm (50), wherein the welding robot (20) has a plasma welding head, and wherein the welding robot (20) has a gripping device for a pressure body feed. [13] Welding robot (20) according to claim 12, characterized by, that the feet (40) of the welding robot (20) have a suction device for attachment to the pressure body (10). [14] Welding robot (20) according to one of claims 12 to 13, characterized by , that the plasma cutting head [formerly: plasma welding head]. The welding head and the gripping device are interchangeably connectable to the multi-axis arm (50). [15] Welding robot (20) according to one of claims 12 to 14, characterized by that the welding robot (20) has at least one camera. [16] Welding robot (20) according to one of claims 12 to 15, characterized by , that the welding robot (20) has four feet (40). [17] Welding robot (20) according to one of claims 12 to 16, characterized by , that the welding robot (20) has a rectangular basic shape. [18] Welding robot (20) according to one of claims 4 to 9, characterized by, that the welding robot's motion programming can be adapted to changes in the underlying construction documents and is not hard-coded.

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