JP2014005862A - Reinforcing tool for steam pipeline - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reinforce a steam pipeline even when it is difficult to secure the space enough to wind a wire, around the steam pipeline because of an obstacle.SOLUTION: A reinforcing tool 1 is disposed along an outer peripheral surface of a metallic steam pipeline X in which creep is incurred by internal high-temperature and high-pressure steam, while surrounding the steam pipeline in the circumferential direction, and configured to reinforce a creep strength of the steam pipeline and comprises a metallic reinforcing member 21 and a fixed member 22. The reinforcing member 21 includes: a curved plate part 21 whose inner peripheral surface is curved with the same curvature as that of the outer peripheral surface of the steam pipeline; and a flange part 21b which is projected from a circumferential edge portion of the curved plate part in a radial direction of the steam pipeline. The fixed member 22 is configured to fix flange parts which are adjacent to each other when disposed on the outer peripheral surface of the steam pipeline, and comprised of e.g., a pair of a bolt 22a and a nut 22b.

Description

  The present invention relates to a reinforcing tool that reinforces the creep strength of steam piping in which creep occurs when high-temperature and high-pressure steam such as power steam flows.

  High-temperature and high-pressure steam is used as power steam used as power for a steam turbine or the like. For example, steam having a steam temperature of 300 ° C. to 650 ° C. and a steam pressure of about 5 Mpa to 8 Mpa is used. Since the steam for power having such high temperature and pressure is flowing, the steam pipe is deteriorated by creep.

  In order to prevent the steam pipe from being destroyed due to creep deterioration, the steam pipe is reinforced. Usually, the method of cut | disconnecting the target part of steam piping and joining healthy piping to a cutting location is taken. However, this method has a problem that it takes time and effort because it involves welding work and heat treatment work of the steam pipe. Therefore, in the method described in Patent Document 1, the steam pipe is reinforced by winding a wire around a target portion of the steam pipe.

JP 2011-185403 A

  In the method described in Patent Document 1, reinforcement can be performed by a simple procedure of winding a wire around a portion to be reinforced in a steam pipe. However, when the reinforcement is performed without cutting out the steam pipe, the beam of the building, a fixing bracket fixing the steam pipe, or the like can be an obstacle when winding the wire. In particular, when winding the wire with a machine, it is necessary to secure a sufficient space around the steam pipe, but it may be difficult to secure a sufficient space because the beams and fixing brackets become obstacles. .

  The present invention has been made in view of such circumstances, and an object thereof is to secure a space of a size necessary for winding a wire around a steam pipe by an obstacle such as a beam or a fixture. Even if it is difficult to do so, the steam pipe can be reinforced.

  In order to achieve the above-mentioned object, the present invention is arranged in a state surrounding the steam pipe in the circumferential direction along the outer peripheral surface of the metal steam pipe where the creep is caused by the internal high-temperature and high-pressure steam, A reinforcing tool for reinforcing strength, a curved plate portion whose inner peripheral surface is curved with the same curvature as the outer peripheral surface of the steam pipe, and a radial edge of the steam pipe from a circumferential edge of the curved plate portion Providing a plurality of metal reinforcing members having projecting flange portions and a plurality of metal fixing members fixing the adjacent flange portions when arranged on the outer peripheral surface of the steam pipe. Features.

  According to the reinforcing tool of the present invention, the reinforcing member made of metal having the curved plate portion and the flange portion is disposed so as to surround the steam piping, and the adjacent flange portions are fixed to each other to reinforce the steam piping. Since it is possible, it is sufficient if there is a space to arrange the reinforcing member or to fix the flange parts together, even if it is difficult to secure a space of the size necessary for winding the wire around the steam pipe, The steam pipe can be reinforced.

  In the above-described reinforcing tool, the flange portion is provided with a through hole penetrating in the plate thickness direction, and the fixing member is fitted to the bolt with a shaft portion penetrating the tube through hole. It is preferable to be composed of a set of nuts. In this configuration, the adjacent flange portions can be fixed with a set of bolts and nuts, so that the configuration can be simplified and work can be performed in a small space.

  In the above-described reinforcing tool, the curved plate portion has a circumferential length in which a predetermined gap is formed between the adjacent flange portions when the steam pipe is surrounded by the plurality of reinforcing members. It is preferable that it is a length. In this structure, expansion | swelling of steam piping can be suppressed by making flange parts adjoin and fix with a fixing member.

  In the above-described reinforcing tool, it is preferable that the flange portion has a thickness greater than that of the curved plate portion. In this configuration, the flange portions can be firmly tightened with the fixing member.

  In the reinforcing tool described above, it is preferable to provide a fillet portion to be joined to each of the flange portion and the curved plate portion at a connection portion between the flange portion and the curved plate portion. In this configuration, the flange portions can be firmly tightened with the fixing member.

  In the above-described reinforcing tool, the steam pipe includes an elbow portion, and includes a plurality of the reinforcing members and a plurality of fixing members, and the length of the outer portion corresponding to the outer bent portion of the elbow portion is the elbow. It is preferable to arrange a plurality of cylindrical reinforcing portions that are defined longer than the length of the inner portion corresponding to the inner bent portion of the portion in the direction of the central axis of the elbow portion. With this configuration, even an elbow portion that is difficult to reinforce can be easily reinforced.

  In the above-described reinforcing tool, it is preferable that the reinforcing member is made of a metal having a creep strength higher than that of the metal constituting the steam pipe. In this configuration, the reinforcing strength can be increased.

  According to the present invention, it is possible to reinforce the steam pipe even when it is difficult to secure a space of a size necessary for winding the wire around the steam pipe due to obstacles such as beams and fixing brackets. .

It is a figure explaining the elbow part of the steam piping reinforced with the reinforcement tool. It is a cross-sectional view of steam piping reinforced with a reinforcing tool (reinforcing part). It is sectional drawing which expands and shows a flange part and a fillet part. It is explanatory drawing of a reinforcement operation | work and shows the elbow part of the steam piping used as reinforcement object. It is a figure explaining a mode that a pair of reinforcement members are arranged in steam piping. It is a figure explaining the state which fixed the pair of arrange | positioned reinforcement member with the fixing member. It is a figure explaining the attachment state of a 1st reinforcement part. It is a figure explaining the state which attached the 1st-3rd reinforcement part. It is a figure explaining the state which attached all the reinforcement parts. It is a figure explaining other embodiment from which the number of reinforcement parts differs.

  Hereinafter, embodiments of the present invention will be described. FIG. 1 is a diagram illustrating a steam pipe X reinforced with a reinforcing tool.

  The steam pipe X shown in FIG. 1 is for supplying power steam (steam temperature = 300 ° C. to 650 ° C., steam pressure = 5 Mpa to 8 Mpa) to the internal space over a long period of time, and creep is generated by this power steam. It will occur. Since high-temperature and high-pressure steam flows, the steam pipe X is made of ferritic chromium steel (for example, 9Cr to 12Cr) having a low coefficient of thermal expansion.

  The diameter of the steam pipe X varies depending on the application, but is determined within a range of 200 mm to 1000 mm, for example. Further, the wall thickness tx (see FIG. 2) of the steam pipe X is determined in the range of 40 mm or more and 70 mm or less. The diameter and thickness of the steam pipe X are determined in consideration of various conditions such as the temperature, pressure, flow rate, and flow speed of the power steam.

  The portion to be reinforced in this embodiment is an elbow portion bent at approximately 90 degrees (L-shaped). This elbow part is a state connected to the other part in the steam pipe X, that is, a state where it is not cut out. Such an elbow part is being fixed to the beam of a building etc. via the fixing metal fitting, and it may be difficult to wind a wire around a peripheral part with a machine.

  A reinforcement tool 1 that reinforces the creep strength of the steam pipe X is attached to a portion to be reinforced of the steam pipe X. The reinforcing tool 1 is composed of a cylindrical first reinforcing portion 11 to a fifth reinforcing portion 15, and surrounds the steam pipe X in the circumferential direction along the outer peripheral surface of the steam pipe X, and It arrange | positions in the state located in a line with the center axis direction of the steam piping X (elbow part).

  Since each reinforcement part 11-15 is arrange | positioned at the elbow part, it is the extension direction of steam piping X by the inner part corresponding to the inner side bending part of an elbow part, and the outer side part corresponding to the outer side bending part of an elbow part. The length in is different. That is, the length of the outer portion of each reinforcing portion 11 to 15 is determined to be longer than the length of the inner portion.

  And each reinforcement part 11-15 is produced with the raw material whose creep strength is larger than the raw material (ferritic chromium steel) of the steam pipe X. For example, stainless steel, nickel alloy, cobalt alloy, and high chromium steel are used. As described above, the reason why each of the reinforcing portions 11 to 15 is made of a material having a higher creep strength than the material of the steam pipe X is to increase the reinforcing strength of the steam pipe X.

  As shown in FIG. 2, each reinforcing portion 11 to 15 includes a pair of reinforcing members 21 and a fixing member 22. The reinforcing member 21 is a portion that surrounds the portion to be reinforced by being disposed along the circumferential direction of the outer peripheral surface of the steam pipe X, and includes a curved plate portion 21a and a flange portion 21b. The fixing member 22 is a member for fixing the flange portions 21b adjacent to each other in the circumferential direction when arranged on the outer peripheral surface of the steam pipe X.

  The curved plate portion 21a is a plate-like member whose inner peripheral surface is curved with the same curvature as the outer peripheral surface of the steam pipe X. In the present embodiment, since each of the reinforcing portions 11 to 15 has the two reinforcing members 21, the curved plate portion 21 a is configured by a plate-like member that is curved in a semicircular shape. The plate thickness ta of the curved plate portion 21a is determined to be thinner than the wall thickness tx of the steam pipe X. For example, when the steam pipe X is made of 9 chrome steel with a wall thickness of 40 mm and the reinforcing member 21 is made of austenitic stainless steel (for example, SUS304), the plate thickness ta of the curved plate portion 21a is 5 mm or more and 15 mm or less. Determined in scope. That is, the plate thickness ta of the curved plate portion 21a is set to about 1/8 to 3/8 of the wall thickness tx of the steam pipe X.

  As shown in FIG. 3, the flange portion 21b is a plate-like portion protruding from the circumferential edge of the curved plate portion 21a in the radial direction of the steam pipe X, and is made of the same material as the curved plate portion 21a. It is manufactured integrally with the portion 21a. The plate thickness tb of the flange portion 21b is determined to be larger than the plate thickness ta of the curved plate portion 21a. This is because when the fixing member 22 is fixed, a large load is applied to the flange portion 21b. That is, the plate thickness tb of the flange portion 21b is set to be larger than the plate thickness ta of the curved plate portion 21a so as to sufficiently withstand the tightening force by the fixing member 22. In FIG. 3, the plate thickness tb of the flange portion 21b is set to twice the plate thickness ta of the curved plate portion 21a. However, the ratio is not limited to this. For example, it can be set to a ratio of 2 to 3 times.

  The flange portion 21b is formed with a through hole 21c penetrating in the plate thickness direction. This is because the fixing member 22 of the present embodiment is configured by a set of bolts 22a and nuts 22b. The through hole 21c is formed in each flange portion 21b. And when fixing each reinforcement part 11-15, each through-hole 21c formed in a pair of flange part 21b adjacent to the circumferential direction is located substantially concentrically. Thereby, the axial part of the volt | bolt 22a can be penetrated. As shown in FIG. 1, in the present embodiment, the pair of flange portions 21 b are fixed by three fixing members 22. For this reason, three through holes 21c are also formed side by side in the axial direction of the steam pipe X.

  Here, as shown in FIG. 3, when the steam pipe X is surrounded by the pair of reinforcing members 21, a predetermined gap sp is formed between the flange portions 21 b adjacent in the circumferential direction. That is, the circumferential length of the curved plate portion 21a is determined to be a length in which the gap sp is formed between adjacent flange portions 21b. The gap sp is formed by the reinforcing portions 11 to 15 to suppress the expansion of the steam pipe X. Specifically, by fixing the flange portions 21b close to each other with the fixing member 22, the curved plate portion 21a can be pulled in the circumferential direction by the gap sp. Thereby, the steam pipe X is fastened by the curved plate portion 21a, and the expansion of the steam pipe X can be counteracted.

  Further, a fillet portion 21d is provided at a connection portion between the flange portion 21b and the curved plate portion 21a. The fillet portion 21d is made of a weld metal (welded joint) having a triangular cross section. The fillet portion 21d is welded to each of the flange portion 21b and the curved plate portion 21a. Even when a large tightening force is applied to the flange portion 21b, the flange portion 21b is bent or damaged. Suppress malfunctions. For this reason, it is preferable that the fillet portion 21 d is formed up to just below the fixing member 22. This fillet portion 21d can be produced, for example, by fillet welding to the connection portion.

  Next, the fixing member 22 will be described. As described above, the fixing member 22 is a member for fixing the adjacent flange portions 21b to each other. As shown in FIG. 3, the fixing member 22 is constituted by a set of a bolt 22a and a nut 22b fitted to the bolt 22a. Yes. The fixing member 22 is made of a material having a higher creep strength than the material of the steam pipe X, like the reinforcing member 21. In the present embodiment, the reinforcing member 21 is made of the same material (for example, SUS304).

  With respect to the shaft portion of the bolt 22a, its diameter is determined to be smaller than the diameter of the through hole 21c, and its length is determined to be longer than the length obtained by adding the thickness of the nut 22b to twice the plate thickness tb of the flange portion 21b. It has been. Furthermore, the size of the head of the bolt 22a is determined to be larger than the diameter of the through hole 21c. Accordingly, the flange portions 21b can be firmly fixed to each other by sandwiching the pair of flange portions 21b between the head portion of the bolt 22a and the nut 22b and tightening the nut 22b to the shaft portion of the bolt 22a.

  As shown in FIG. 1, in this embodiment, a pair of flange portions 21b are fixed by three fixing members 22 (a set of bolts 22a and nuts 22b) to distribute the load. Note that the number of the fixing members 22 is not limited to three and can be determined as appropriate.

  Next, the reinforcement operation | work of the steam piping X by the above-mentioned reinforcement tool 1 is demonstrated. In this description, the reinforcement work for the elbow portion of the steam pipe X shown in FIG. 4 will be described. When reinforcing the elbow portion, first, the first reinforcing portion 11 (see FIG. 1) is attached.

  In this case, as shown in FIG. 5, after one reinforcing member 21 serving as the first reinforcing portion 11 is disposed in one half of the steam pipe X, the other reinforcing member 21 serving as the first reinforcing portion 11 is replaced with the steam pipe. It is arranged on the opposite side of X. Then, as shown in FIG. 6, the adjacent flange portions 21b are fastened and fixed by a fixing member 22 (a set of bolts 22a and nuts 22b). Thereby, the 1st reinforcement part 11 is attached to the steam piping X, as shown in FIG.

  When the attachment of the first reinforcing portion 11 is completed, the second reinforcing portion 12 is attached. Attachment of the 2nd reinforcement part 12 is performed in the procedure similar to the attachment of the 1st reinforcement part 11. FIG. That is, after arranging the pair of reinforcing members 21 so as to surround the steam pipe X, the adjacent flange portions 21 b are fastened and fixed by the plurality of fixing members 22. And the 3rd reinforcement part 13 is attached in the same procedure following the 2nd reinforcement part 12. FIG. FIG. 8 shows the elbow portion with the first reinforcing portion 11, the second reinforcing portion 12, and the third reinforcing portion 13 attached thereto. Thereafter, the fourth reinforcing portion 14 and the fifth reinforcing portion 15 are attached in the same manner. Thereby, as shown in FIG. 9, all the reinforcement parts are attached and the reinforcement work is completed.

  As can be seen from the above description, in the reinforcing tool 1 of the present embodiment, the metal reinforcing member 21 having the curved plate portion 21a and the flange portion 21b is disposed so as to surround the steam pipe X, and the adjacent flanges. The steam pipe X can be reinforced by fixing the portions 21b. For this reason, it is sufficient if there is a space for arranging the reinforcing member 21 or fixing the flange portions 21b, and it is difficult to secure a space of a size necessary for winding the wire around the steam pipe X. Even in this case, the steam pipe X can be reinforced. For example, after the curved plate portion 21a of the reinforcing member 21 is brought into contact with the outer surface of the steam pipe X in a place where there is a sufficient working space around the steam pipe X, the reinforcing member 21 is along the axial direction of the steam pipe X. By moving, the reinforcing member 21 can be positioned at a desired location, and reinforcement can be performed.

  The reinforcing tool 1 includes five cylindrical reinforcing portions 11 to 11 in which the length of the outer portion corresponding to the outer bent portion of the elbow portion is set longer than the length of the inner portion corresponding to the inner bent portion of the elbow portion. 15. And since each reinforcement part 11-15 is arrange | positioned in the central-axis direction of an elbow part, even if it is an elbow part which is difficult to reinforce because of work space, it can be easily reinforced.

  In the reinforcing tool 1, the flange portion 21 b is provided with a through hole 21 c that penetrates in the plate thickness direction. The fixing member 22 includes a bolt 22 a whose shaft portion penetrates the tube passage hole, and the bolt 22 a. Since the nuts 22b are fitted together, the adjacent flange portions 21b can be fixed with a simple configuration. Further, the fixing work can be performed in a small space.

  The circumferential length of the curved plate portion 21a is determined so that a predetermined gap sp is formed between the adjacent flange portions 21b when the steam pipe X is surrounded by the plurality of reinforcing members 21. ing. Thereby, the steam pipe X can be firmly tightened by fixing the flange portions 21b close to each other with the fixing member 22, and the expansion of the steam pipe X can be counteracted.

  Further, regarding the flange portion 21b, the plate thickness tb is set larger than the plate thickness ta of the curved plate portion 21a. In addition, a fillet portion 21d joined to each of the flange portion 21b and the curved plate portion 21a is provided at a connection portion between the flange portion 21b and the curved plate portion 21a. Thus, even when the flange portions 21b are strongly tightened, the joined state with the curved plate portion 21a can be maintained.

  The above description of the embodiment is for facilitating the understanding of the present invention, and does not limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof. For example, you may comprise as follows.

  In the above-mentioned embodiment, although the reinforcing tool 1 was comprised from the five reinforcement parts 11-15, the number of reinforcement parts is not limited to five. For example, as shown in FIG. 10, the reinforcing tool 1 ′ may be composed of four reinforcing portions 11 ′ to 14 ′.

  In the above-described embodiment, the elbow pipe reinforcing tool 1 has been described. However, a straight pipe reinforcing tool can be configured similarly. And it can also comprise by the reinforcement part about the reinforcement tool for straight pipes.

  In the reinforcing tool 1 described above, the steam pipe X is surrounded by the two reinforcing members 21, but is not limited to this configuration. For example, the steam pipe X may be surrounded by three reinforcing members, or the steam pipe X may be surrounded by four reinforcing members. That is, any configuration may be used as long as the steam pipe X is surrounded by a plurality of reinforcing members.

  The fixing member 22 described above is configured by a set of bolts 22a and nuts 22b, but is not limited to this configuration. For example, like a vise, you may press a pair of flange part 21b toward inner side from the outer side.

  Further, the steam pipe X is not limited to the one that flows steam for power. The present invention can be applied to any steam pipe X through which high-temperature and high-pressure steam similar to power steam flows and which undergoes creep degradation.

DESCRIPTION OF SYMBOLS 1 ... Reinforcement tool, 11 ... 1st reinforcement part, 12 ... 2nd reinforcement part, 13 ... 3rd reinforcement part, 14 ... 4th reinforcement part, 15 ... 5th reinforcement part, 1 '... Reinforcement tool, 11' ... 1st DESCRIPTION OF SYMBOLS 1 reinforcement part, 12 '... 2nd reinforcement part, 13' ... 3rd reinforcement part, 14 '... 4th reinforcement part, 21 ... Reinforcement member, 21a ... Curve board part, 21b ... Flange part, 21c ... Through-hole, 21d ... fillet part, 22 ... fixing member, 22a ... bolt, 22b ... nut, X ... steam pipe, tx ... wall thickness of steam pipe, ta ... plate thickness of curved plate part, tb ... plate thickness of flange part, sp ... Gap formed between flanges

Claims (7)

It is arranged in a state surrounding the steam pipe in the circumferential direction along the outer peripheral surface of the metal steam pipe where creep is generated by internal high-temperature and high-pressure steam, and is a reinforcing tool for reinforcing the creep strength of the steam pipe,
A plurality of curved plate portions having an inner peripheral surface curved with the same curvature as the outer peripheral surface of the steam pipe, and flange portions projecting in a radial direction of the steam pipe from a circumferential edge of the curved plate portion. A metal reinforcing member,
A reinforcing tool comprising a plurality of metal fixing members for fixing the adjacent flange portions when arranged on the outer peripheral surface of the steam pipe. The flange portion is provided with a through hole penetrating the plate thickness direction,
2. The reinforcing tool according to claim 1, wherein the fixing member is configured by a set of a bolt having a shaft portion penetrating the pipe through-hole and a nut fitted to the bolt. The curved plate portion is
The circumferential length is such a length that a predetermined gap is formed between the adjacent flange portions when the steam pipe is surrounded by a plurality of the reinforcing members. 2. The reinforcing tool according to 2. The flange portion is
The reinforcing tool according to any one of claims 1 to 3, wherein a thickness thereof is larger than a thickness of the curved plate portion.   The fillet part joined to each of the said flange part and the said curved board part was provided in the connection part of the said flange part and the said curved board part, The any one of Claim 1 to 4 characterized by the above-mentioned. Reinforcing tool as described. The steam pipe includes an elbow portion,
A plurality of the reinforcing members and a plurality of the fixing members are provided, and the length of the outer portion corresponding to the outer bent portion of the elbow portion is longer than the length of the inner portion corresponding to the inner bent portion of the elbow portion. The reinforcing tool according to any one of claims 1 to 5, wherein a plurality of defined cylindrical reinforcing portions are arranged in a central axis direction of the elbow portion. The reinforcing member is
The reinforcing tool according to any one of claims 1 to 6, wherein the reinforcing tool is made of a metal having a higher creep strength than a metal constituting the steam pipe.

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