Device for clamping screw connections

Abstract

Device for clamping screw connections, which has at least one hydraulic cylinder connected to a pressure generator via at least one line, characterized in that the device is integrated into a flange (4) of a flange connection.

Description

[0001] The invention relates to a device for tightening screw connections, which has at least one hydraulic cylinder which is connected to a pressure generator via at least one line.

[0002] Such devices are typically referred to as screw tensioning devices. Known designs of screw tensioning devices are described, for example, in DE 10 2018 110 517 A1 and DE 10 2018 117 061 A1.

[0003] Bolt tensioners are typically used to tension large bolted joints. Such large joints often have multiple bolts and nuts. The bolts are typically made of steel and have relatively large diameters, depending on the intended loads.

[0004] According to a typical embodiment, a bolt tensioning device has a hydraulic cylinder. Ring cylinders are typically used. Located near the cylinder is a receptacle for the end of the bolt to be tightened, or for a nut or threaded sleeve. A nut, which tightens the bolt, is typically located within the ring cylinder.

[0005] According to a common, well-known workflow, the ring cylinder pulls the bolt over the upper threaded sleeve or nut with a force slightly exceeding the typical load capacity of the bolted connection. The actual nut intended for the bolted connection can then be screwed forcelessly onto the flange below. According to the state of the art, exactly as many bolt tensioners are used as there are bolts to be tightened. After the bolting is completed, the pressure in the hydraulic tensioner is released, and the bolt tensioner can be removed.

[0006] To loosen the screw connection, the procedure described above is carried out in reverse order.

[0007] A disadvantage of conventional bolt tensioning devices is their relatively high weight. A typical weight per device is approximately 50 kg. This results in a very high total weight, especially when a large number of bolts are to be tightened. However, the weight of the bolt tensioning device also depends significantly on its size. For example, the weight of a conventional M20 steel bolt tensioning device is approximately 30 kg, while that of an M100 bolt tensioning device is approximately 100 kg.

[0008] It has also been known for a long time that screw tensioning devices can be made of aluminum, so that the weight can be reduced by about 2 / 3.

[0009] The resulting high weight is particularly disadvantageous when pressure intensifiers or pressure vessels are used. The clamping devices must be lifted onto the pressure intensifier or pressure vessel. Lifting devices are often required for this purpose. Another disadvantage of conventional screw clamping devices is the frequent occurrence of assembly errors and the very labor-intensive installation of hoses. Furthermore, the housing of the screw clamping devices is relatively expensive to manufacture.

[0010] The object of the present invention is to construct a screw tensioning device of the type mentioned in the introduction in such a way that the application is simplified, that the probability of errors is reduced and that a cheaper production is supported.

[0011] This object is achieved according to the invention in that the device is arranged as part of a pressure intensifier in a high-pressure flange of a pressure intensifier or another component.

[0012] The arrangement of the bolt tensioning device as part of the pressure intensifier or other component allows the bolt tensioning device to be mounted with the flange on the pressure intensifier or other component. This results in an extremely simple and precisely defined workflow that significantly reduces the occurrence of assembly errors.

[0013] A typical application of the screw tensioning device according to the invention is for flange connections and in particular for flange screw connections.

[0014] Examples of applications include high-pressure flanges of pressure intensifiers, pressure vessels or marine diesel engines.

[0015] The following figures schematically illustrate exemplary embodiments of the invention. They show: Fig. 1: A partially sectioned perspective view of a pressure intensifier with integrated screw tensioning device, Fig. 2: A partially sectioned side view of the pressure intensifier according to Fig. 1, Fig. 3: An enlarged view of detail A from Fig. 2, whereby a pressure-free hydraulic system ensures that the screw tensioning device is in a relaxed state, Fig. 4: The arrangement according to Fig. 3 with pressurised hydraulics and raised pressure plate of the screw tensioning device, Fig. 5: The arrangement according to paragraph 4 with pressurised hydraulics, tensioned screw tensioning device and stretched screw, Fig. 6: The arrangement according to Fig. 5 with tensioned screw tensioning device and pressure-free hydraulics, whereby the pressure plate of the screw tensioning device is supported on the threaded ring, Fig. 7: A design variant in which the pressure build-up takes place via one or more hydraulic connections, Fig. 8: A horizontal section along section line AA in Fig. 7, Fig. 9: A design variant in which the pressure distribution takes place outside the flange and the individual bolt tensioning devices are controlled via several hydraulic connections, Fig. 10: A vertical section along section line AA in Fig. 9.

[0016] The perspective representation in Fig. 1 shows a pressure intensifier (10) with integrated screw tensioning device (11).

[0017] The illustrated embodiment features tie rods (1) that can be screwed to hexagon nuts (2) via external threads. The pressure intensifier (10) has a high-pressure flange (4). Pressure plates (3) of the bolt tensioning device (11) are arranged in the area of ​​the high-pressure flange (4).

[0018] Fig. 2 shows a partially sectioned side view of the pressure intensifier (10) according to Fig. 1. The sectional view is shown in the area of ​​the screw tensioning device (11) integrated into the high-pressure flange (4).

[0019] From the enlarged detail view in Fig. Figure 3 shows the structural design of the bolt tensioning device (11) in more detail. In particular, the arrangement of a large hydraulic seal (5) and a small hydraulic seal (6) can be seen. Furthermore, a threaded ring (7) of the tension rod (1) can be seen.

[0020] The high-pressure flange (4) is provided with at least one hydraulic connection (12). At least one hydraulic channel (13) extends from the hydraulic connection (12) within the high-pressure flange (4). A corresponding pressure generator (not shown) is connected to the hydraulic connection (12) for operating the bolt tensioning device (11).

[0021] In the Fig. In the functional state shown in Figure 3, the hydraulic system is depressurized and the screw tensioning device (11) is relaxed.

[0022] According to the operating status in Fig. 4, the hydraulic system is pressurized and raises the pressure plate (4) of the bolt tensioning device (11). In this operating state, the threaded ring (7) can be screwed up to a web (14) of the pressure plate (3).

[0023] According to a preferred embodiment, the pressure plate (3) has an approximately circular outer boundary relative to a vertical center line (15). The large hydraulic seal (5) seals the pressure plate (3) relative to the high-pressure flange (4) along an outer circumference of the pressure plate (3). The web (14) is preferably formed integrally with the pressure plate (3) and extends sleeve-like along the center line (15). The small hydraulic seal (6) seals the web (14) in the region of its outer circumference relative to the high-pressure flange (7).

[0024] According to the presentation in Fig. 6, the hydraulic system is depressurized, and the pressure plate (3) is supported by the threaded ring (7) via the web (14). The screw tensioning device (11) is thus tensioned despite the depressurized hydraulic system, and the screw is stretched.

[0025] Fig. Figure 7 shows a variant of the pressure intensifier (10) in which internal threads for sealing plugs or connecting lines are arranged in the area of ​​the hydraulic connection (12). At each of the hydraulic connections (12), all hydraulic channels (13) are interconnected. Pressure buildup occurs evenly at all screws. The pressure buildup thus takes place within the high-pressure flange (4) through the use of multiple hydraulic connections (12).

[0026] Fig. Figure 8 shows in a vertical section the arrangement of the hydraulic connections (12) and the hydraulic channels (13) according to the embodiment in Fig. 7. Three hydraulic connections (12) are used.

[0027] According to the design variant of the pressure intensifier (10) in Fig. 9, pressure distribution takes place outside the high-pressure flange (4). The individual bolt tensioning devices (11) are each controlled separately via several hydraulic connections (12). All hydraulic channels (13) are connected to each other via each hydraulic connection (12), so that pressure builds up evenly across all bolts.

[0028] Fig. 10 shows a vertical section along section line AA in Fig. 9. It can be seen in particular that a total of four hydraulic connections (12) are used.

[0029] According to a typical workflow, the bolt tensioning device (11) with the high-pressure flange (4) is mounted on the pressure intensifier (10). The high-pressure flange (4) is connected to a hydraulic pump (not shown) via a hose (not shown).

[0030] The general workflow is as described above: first, the screw tensioning device (11) is pressurized, then the clamping nut is retightened, and then the pressure is released. This avoids the need for a separate assembly of a screw tensioning device (11) according to the prior art workflows.

[0031] The hydraulic cylinder according to the invention is provided by the high-pressure flange (4). Starting from the upper side of the high-pressure flange, a recess extends into the material of the high-pressure flange (4), in which the pressure plate (3) is guided. The pressure plate (3) thus forms a piston guided in the hydraulic cylinder. During the clamping process, the hexagon nut (2) rests on the upper side of the pressure plate (3).

[0032] Between an underside of the pressure plate (3) and a bottom region of the recess in the high-pressure flange (4) is a piston interior into which at least one of the hydraulic channels (13) opens. Preferably, at least one of the hydraulic channels (13) extends in the direction of the center line (15). This typically runs in a horizontal direction. According to another typical embodiment, at least one connecting channel branches off from the hydraulic channel (13) and opens into the piston interior. The connecting channel preferably runs in a vertical direction.

[0033] Above, the screw tensioning device (11) was explained primarily as a component of the pressure intensifier (10). The inventive function of the screw tensioning device (11) is achieved by its integration into the high-pressure flange (4) of the pressure intensifier (10). According to another definition of the present invention, it is also possible to regard a pressure intensifier (10) with a high-pressure flange (4) as the subject matter of the invention, wherein the screw tensioning device (11) is also integrated into the high-pressure flange (4). As already explained above, an identical inventive principle applies in both perspectives; according to one perspective, the invention relates to the screw tensioning device (11), which has a special arrangement, while according to the other perspective, the invention relates to the pressure intensifier (10) designed according to the invention.

[0034] A screw tensioning device according to the invention as an integrated element of a high-pressure flange also enables the reduction of the overall weight of the respective assembly, since the weight of a separate screw tensioning device is essentially eliminated. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2018 110 517 A1

[0002] DE 10 2018 117 061 A1

[0002]

Claims

[1] Device for tightening screw connections, comprising at least one hydraulic cylinder connected to a pressure generator via at least one line, characterized by that the device is integrated into a flange (4) of a flange connection. [2] Device according to claim 1, characterized by that at least one hydraulic channel (13) is arranged within the high-pressure flange (4). [3] Device according to claim 1, characterized by that the device is designed for clamping flange screw connections. [4] Device according to claim 1, characterized by that the device is designed for clamping flange connections. [5] Device according to one of claims 1 to 4, characterized by that a pressure distribution is formed within the high-pressure flange (4). [6] Device according to one of claims 1 to 4, characterized bythat a pressure distribution is formed outside the high-pressure flange (4). [7] Device according to one of claims 1 to 6, characterized by that a pressure plate (3) of the screw tensioning device (11) has an approximately circular outer contour. [8] Device according to claim 7, characterized by that the pressure plate (3) is connected to a web (14). [9] Device according to claim 8, characterized by that the web (14) has a sleeve-like design. [10] Device according to one of claims 1 to 9, characterized by that the pressure plate (3) and the web (14) are formed in one piece. [11] Device according to one of claims 1 to 10, characterized by that it is arranged in the high-pressure flange of a pressure intensifier (10)

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