Pipe cutting device for plant facility

Abstract

To provide a pipe cutting device for efficiently performing cutting work while supporting a pipe on a structure so that there is no danger that the pipe jumps unexpectedly when cutting the pipe.SOLUTION: The pipe cutting device 1 includes a pair of openable and closable annular fixing bands 2 disposed at a predetermined interval on both sides in the axial direction of a cutting scheduled portion of a pipe P installed in a plant or the like and fixed to the outer periphery of the pipe P, and an openable and closable annular torch support member 3 that connects the pair of fixing bands 2 and is rotatably held between the fixing bands 2 along the outer periphery of the pipe P. The torch-supporting member 3 is provided with a torch-connecting part 31a for fixing the cutting torches 4 by directing the tip of the nozzle to the outer periphery of the piping P, and handle 31b and 32b for rotating the outer periphery of the piping P while operating the cutting torches 4. The pair of fixing bands 2 includes an ear 23b for connecting a hanging member H for hanging on a structure S.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pipe cutting device used when cutting and removing pipes installed in a plant such as a decommissioned nuclear power plant. [Background technology]

[0002] Piping installed in plants and other facilities is supported by constant hangers, spring hangers, rigid hangers, etc. In order to cut the pipe, it is necessary to remove these hangers, but after removal, it is necessary to install supports (lifting tools, temporary hangers, etc.) that can bear the same load in place of the hangers. When cutting the pipe after the supports have been installed, the mass balance and residual stress of the pipe may cause the pipe to bounce unexpectedly at the moment of cutting, or the direction of the bounce may be unpredictable, which may pose a risk to the safety of workers. Meanwhile, a known pipe cutting device is disclosed in Patent Document 1. This device is equipped with an openable and closable ring-shaped body that is attached so as to hug the outer periphery of the pipe. The ring-shaped body is composed of a fixed part that is fixed to the outer periphery of the pipe with a clamp, and a rotating part that is supported so as to rotate around the pipe by bearings provided circumferentially on the end face of the fixed part. A drive source and a power transmission mechanism for rotating the rotating part are provided on the fixed part. The rotating part is provided with a disc cutter blade and a mechanism for moving it in the radial direction of the pipe. The driving force of the moving mechanism is transmitted via the power transmission mechanism to the rotating part, causing it to operate on an external gear on the outer periphery of the fixed part. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-245115 Summary of the Invention [Problem to be solved by the invention]

[0004] To provide a pipe cutting device capable of efficiently performing cutting work while supporting a pipe on a structure so that the pipe will not jump unexpectedly and endanger the safety of workers when cutting the pipe installed in a plant. [Means for solving the problem]

[0005] In the following description, reference will be made to the reference numerals in the accompanying drawings, but the present invention is not limited thereto. To solve the above problems, the pipe cutting device 1 of the present invention includes a pair of fixing bands 2 arranged at a predetermined distance on both axial sides of a section of a pipe P installed in a plant or the like, and a torch support member 3 rotatably held between the fixing bands 2 along the outer periphery of the pipe P. Both the fixing bands 2 and the torch support member 3 are annular and can be opened and closed. The torch support member 3 includes a torch connection portion 31a that fixes the nozzle tip of a cutting torch 4 toward the outer periphery of the pipe P, and handles 31b and 32b for rotating the outer periphery of the pipe P while operating the cutting torch 4. [Effects of the Invention]

[0006] According to the pipe cutting device of the present invention, the pipe can be supported to a structure with a pair of fixing bands, while the cutting torch can be moved with a torch support member, allowing for efficient cutting operations.Even after the pipe is cut, the pair of fixing bands and the torch support member restrain the pipe on both sides of the cut area, preventing the pipe from accidentally bouncing and threatening the safety of workers. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view of a state in which the pipe cutting device of the present invention is attached to a pipe. [Figure 2] FIG. 2 is a front view of the pipe cutting device of FIG. [Figure 3] 2 is a side view of the pipe cutting device of FIG. 1 with a portion cut away. [Figure 4] FIG. 2 is an explanatory diagram of an example of use of the pipe cutting device of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of the present invention will be described with reference to the drawings. The pipe cutting device 1 comprises a pair of fixing bands 2 fixed to the outer periphery of a pipe P installed in a plant or the like, spaced apart in the axial direction, and a torch support member 3 held between the fixing bands 2 so as to be freely rotatable along the outer periphery of the pipe P.

[0009] The fixing band 2 is an openable and closable ring-shaped body, and is formed by connecting first and second semicircular band members 21 and 22 with bolts B1 at their connecting pieces 21a and 22a. The pair of fixing bands 2 are arranged facing each other at a predetermined distance on both sides of the axial direction of the intended cutting location of the pipe P.

[0010] Each fixing band 2 has a fixing portion 23 fixed to the outer periphery of the pipe P and a guide portion 24 that holds the torch support member 3. The fixing portion 23 is arranged on the outer axial side of the pipe P (opposite the opposing side), and the guide portion 24 is arranged on the inner axial side (opposite the opposing side). The joining pieces 21a, 22a are provided on the fixing portion 23. An ear 23b is fixed to the outer surface of the fixing portion 23 of the first band member 21. The ear 23b can be connected to a hanging member H (Figure 4) that suspends the cutting device 1 together with the pipe P from a structure S.

[0011] 2, the fixing portion 23 has a plurality of threaded holes 23a that are provided radially toward the center of the pipe P and at equal intervals in the circumferential direction. The fixing portion 23 is fixed to the pipe P by a plurality of auxiliary bolts B2 that are screwed into the threaded holes 23a so that their tips abut against the outer periphery of the pipe P.

[0012] As shown in FIG. 3, the guide portion 24 includes an annular guide groove 24a that opens outward in the radial direction of the pipe P, and an annular protruding edge portion 24b that protrudes inward from the upper edge of the guide groove 24a.

[0013] As clearly shown in FIGS. 1 and 3, the torch support member 3 is made up of first and second semicircular arc-shaped halves 31 and 32 that are butted together, and is rotatably supported on both sides by the guide portions 24 of the fixing band 2.

[0014] As shown in FIG. 3, the torch support member 3 is a member with a roughly U-shaped cross section, having an annular cover portion 33 and annular sliding protrusions 34 protruding inward from both edges of the annular cover portion 33. By engaging the sliding protrusions 34 with the guide grooves 24a, the fixing bands 2 on both sides are connected, and the fixing bands 2 are held in place by the protruding edges 24b.

[0015] A cover portion 33 of the first half 31 of the torch support member 3 is provided with a torch connection portion 31a that secures the tip of the nozzle of the cutting torch 4 facing the outer periphery of the pipe P. The cover portion 33 closes the space between the fixing band 2 and the outer periphery of the pipe P, thereby suppressing the spread of sparks when the pipe P is cut. The torch support member 3 has handles 31b, 32b on its outer periphery. An operator cuts the pipe P by gripping the handles 31b, 32b and rotating the torch support member 3 together with the cutting torch 4 around the pipe P. An observation window 3c is formed in the torch support member 3, and the operator can check the cutting status of the pipe P through the observation window 3c.

[0016] When cutting a pipe P, as shown in a typical use example of the cutting device 1 in Figure 4, supports such as constant hangers, spring hangers, and rigid hangers installed between anchor sections AA of the pipe P are removed, and instead, the cutting device 1 is attached to the required location on the pipe P to support the load equivalent to that of the supports, and is supported on the structure S with a hanging support member H. Then, while the torch support member 3 is rotated around the pipe P, the pipe P is cut one by one with the cutting torch 4 attached to it. Even after cutting, the pipe P remains connected and held in position by the cutting device 1, preventing the pipe P from bouncing after cutting. Even after cutting, the rigidity of the pipe P is maintained by the cutting device 1, so there is no need to worry about it falling. When removing the pipe P, only the mass of the pipe P needs to be taken into consideration. [Explanation of symbols]

[0017] 1 Pipe cutting device 2 fixing bands 21 First band member 21a Joint piece 22 second band member 22a Joint piece 23 Fixed part 23a screw hole 23b Year 24 Guide section 24a Circular guide groove 24b Edge 3 Torch support member 31 First Half 31a Torch connection part 31b Operating handle 31c Observation window 32 Second Half 32b Operating handle 33 Cover 34 Sliding protrusion 4 Cutting torch B1 Bolt B2 Auxiliary bolt H Hanging support material P piping S construct

Claims

1. A pair of openable and closable annular fixing bands are arranged at a predetermined interval on both sides of the axial direction of the planned cutting point of the installed pipe and are fixed to the outer periphery of the pipe; an openable and closable annular torch support member that connects the pair of fixing bands and is rotatably held between the fixing bands along the outer periphery of the piping; The pipe cutting device for plant facilities is characterized in that the torch support member is provided with a torch connection portion that fixes the tip of the nozzle of a cutting torch toward the outer periphery of the pipe.

2. 2. The pipe cutting device for plant facilities according to claim 1, wherein the torch support member includes a handle for rotating the outer periphery of the pipe along the fixing band while operating the cutting torch.

3. 2. The pipe cutting device for plant facilities according to claim 1, wherein the pair of fixing bands are provided with ears for connecting a suspension member for suspending the device from a structure.

4. each of the pair of fixing bands includes a fixing portion fixed to an outer periphery of the pipe on an outer side in the axial direction of the pipe, and a guide portion on an inner side that engages with the torch support member; The guide portion of the fixing band has an annular guide groove that opens radially outward of the pipe, The pipe cutting device for plant equipment described in claim 1, characterized in that the torch support member comprises a pair of annular sliding protrusions that slidably engage with the guide groove, and an annular cover portion that connects the sliding protrusions and closes the space between the pair of fixing bands and the outer circumference of the pipe.

5. The pair of fixing bands each include a first and a second band member having a semicircular arc shape, 2. The pipe cutting device for plant facilities according to claim 1, wherein the first and second band members each have connecting pieces at both ends thereof for butting together and fastening with a bolt.

6. The joining piece is provided on the fixing portion, The pipe cutting device for plant equipment described in claim 5, characterized in that the fixing portion has a plurality of threaded holes arranged radially toward the center of the pipe at equal intervals around the circumferential direction, and is fixed to the pipe by a plurality of auxiliary bolts that are screwed into the threaded holes so that their tips abut the outer periphery of the pipe.

7. the torch support member is composed of first and second semicircular arc-shaped halves arranged with both ends abutting each other, Each half of the torch support member is formed into a generally U-shaped cross section with the engaging portion protruding inward from both edges of the cover portion, the guide portion of the fixing band includes an annular protruding edge portion protruding inward from an upper edge portion of the guide groove, Each half of the torch support member is held by the flange portion in the guide portion; The torch connection portion is provided on one half of the torch support member.

5. The pipe cutting device for plant facilities according to claim 4.

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