JP6270048B2 - Temporary piping for power plant and piping installation method for power plant - Google Patents

Description

  Embodiments described herein relate generally to a temporary pipe for a power plant and a pipe installation method for a power plant using the temporary pipe.

  In the construction of the power plant, after the piping is installed, the inside of each piping is chemically cleaned. In the chemical cleaning, a cleaning liquid is caused to flow inside each pipe in order to remove foreign matters such as rust and oil and fat inside each pipe. Usually, a pressure test is performed before chemical cleaning in order to check in advance for leakage of the cleaning liquid. In the pressure test, each pipe is filled with a high pressure pressure resistant liquid and inspected for leakage of the pressure resistant liquid. As a factor that the pressure-resistant liquid leaks, there is a defect in a welded portion that becomes a joint between adjacent pipes.

  During pressure test and chemical cleaning, if piping parts such as regulating valves, safety valves, orifices or flow nozzles are interposed between the pipes, they may be clogged or damaged by foreign matter inside the pipe that flows with the pressure water, There is a concern that the quality may deteriorate due to the cleaning liquid. Therefore, these piping parts are removed before the pressure test, and a closing cap is welded to each of the end faces of the two pipes instead of the equipment. After sealing the inside of the pipe with a closing cap, a large amount of pressure-resistant liquid is filled and a pressure-resistant test is performed. After the pressure test, the pressure water is drained to remove each closing cap. Then, the closing cap welded to the end face of each pipe is removed with a grinder, and two adjacent pipes are connected with a temporary pipe instead of the closing cap. At this time, temporary piping is fixed to each piping by performing butt welding with respect to the edge of each piping.

  After cleaning the inside of the pipe with the cleaning liquid, cut the entire edge of the pipe to which the temporary pipe is connected, and remove the temporary pipe. Thereafter, the groove is processed again at the edge of the cut pipe, and piping parts such as a regulating valve are welded to the formed edge.

  As described above, in the pipe installation work of the power plant, after the closure cap is welded to the pipe before the pressure resistance test, the closure cap and the temporary pipe are replaced to perform chemical cleaning. For this reason, in order to perform chemical cleaning of the inside of the piping, a lot of labor and setup work are required, resulting in an increase in man-hours or processes.

Japanese Utility Model Publication No. 4-3286 JP 2003-80192 A

  In particular, after chemical cleaning, the existing piping is cut to replace the temporary piping and the piping parts such as the regulating valve. This not only increases the material cost of the piping, but also cleans the foreign matter generated by the cutting. There was a risk of contamination inside the pipe. Moreover, the heat influence on piping accompanying the welding of a closing cap or temporary piping will also generate | occur | produce. In addition, it is necessary to rework the groove at the edge of the pipe that has been cut in order to attach the piping parts such as the regulating valve, which requires much labor.

  The problem to be solved by the present invention is to provide a temporary piping for a power plant that can easily perform chemical cleaning of the inside of the piping, and a piping installation method for the power plant using the temporary piping.

  The temporary piping which concerns on embodiment is temporary piping used in order to connect the said piping between adjacent piping in the case of the chemical cleaning inside piping accompanying the piping installation of a power plant. The temporary piping includes a first flange portion to which one pipe having a grooved edge portion is attached, a second flange portion to which another pipe is attached, the first flange portion and the second flange portion. And a pipe part provided between them. The first flange portion is provided with a recess for accommodating the edge of the one pipe. The temporary pipe is in a state in which the edge of the one pipe is accommodated in the recess of the first flange, and the first flange can be welded to a portion other than the edge of the one pipe. Yes.

  Moreover, the piping installation method of the power plant which concerns on embodiment has the said characteristic between the process of installing several piping which can be cleaned internally with a washing | cleaning liquid, and two adjacent piping among these piping. Arranging a temporary pipe, connecting the two pipes with the temporary pipe, supplying a pressure-resistant water to the pipe and the temporary pipe, and flowing a chemical cleaning solution to the pipe and the temporary pipe; And a step of removing the temporary piping and installing a piping component in place of the temporary piping.

  According to the temporary piping according to the embodiment, the edge of one pipe is accommodated in the concave portion of the first flange part, and the edge of the one pipe that has been grooved is protected in the first flange. The part can be welded to a part other than the edge of one pipe. For this reason, after chemical cleaning, the temporary piping was removed from the one pipe without cutting the edge of the one pipe, and the alternative piping parts were grooved without performing the groove processing on the edge again. It can be welded to the edge of one pipe. As a result, it is possible to prevent the material of the pipe from being wasted along with the cutting, and to eliminate the possibility that foreign matter generated along with the cutting is mixed into the cleaned pipe. Furthermore, since it is not necessary to apply a groove to the edge of one pipe again, the number of work steps can be greatly reduced. From the above, according to the temporary piping of the present embodiment, chemical cleaning inside the piping can be easily performed.

  Moreover, according to the piping installation method of the power plant which concerns on embodiment, the utilization method of the said temporary piping is provided. For this reason, it becomes possible to perform the piping installation work of a power plant easily.

Schematic which shows an example of a power plant. The schematic perspective view which shows the temporary piping by one embodiment. Sectional drawing of the temporary piping shown in FIG. It is a figure for demonstrating the piping installation method of a power plant, Comprising: The perspective view which shows the process of installing piping and some piping components. It is a figure for demonstrating the piping installation method of a power plant, Comprising: The perspective view which shows the process of connecting two adjacent piping with temporary piping. The top view which shows the process of attaching one piping to the 1st flange part of temporary piping in the process shown in FIG. The top view which shows the process of attaching other piping to the 2nd flange part of temporary piping in the process shown in FIG. It is a figure for demonstrating the piping installation method of a power plant, Comprising: The perspective view which shows the process of supplying pressure-resistant water to each piping inside and temporary piping. It is a figure for demonstrating the piping installation method of a power plant, Comprising: The perspective view which shows the process of removing temporary piping. It is a figure for demonstrating the piping installation method of a power plant, Comprising: The perspective view which connects two adjacent piping with a regulating valve. The flowchart for demonstrating the piping installation method of a power plant.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product. 1 to 9 are diagrams for explaining an embodiment. Among these, FIG. 1 is a schematic diagram illustrating an example of a power plant 1 in which a temporary pipe 2 according to an embodiment is used.

  A power plant 1 shown in FIG. 1 is a so-called thermal power plant. In the power plant 1 shown in FIG. 1, the steam turbine 4 is rotated by high-pressure steam heated by the boiler 3, and the rotation of the steam turbine 4 is transmitted to the generator 5 to generate power. The steam that has rotated the steam turbine 4 travels toward the condenser 6. The steam that has reached the condenser 6 is cooled by a large amount of cooling water to become condensed water. The obtained condensate is circulated by the pump 7 and goes to the boiler 3 again. The power plant 1 is not particularly limited as long as it is a facility for generating power, and another example is a nuclear power plant.

  As shown in FIG. 1, the steam heated by the boiler 3 and the condensate cooled by the condenser 6 flow in the sealed circulation passage 10. The circulation channel 10 is formed by assembling a plurality of pipes 11 and pipe parts 15 such as various valves and nozzles. The assembly procedure of the plurality of pipes 11 and the pipe parts 15 will be described. First, the plurality of pipes 11 and the pipe parts 15 are installed. Next, in order to check whether or not the inside of the pipe is sealed, a high pressure pressure-resistant liquid is supplied into the pipe 11 to perform a pressure resistance test. After the pressure test, in order to remove foreign substances and the like, chemical cleaning is performed inside each pipe by flowing a cleaning solution inside each pipe.

  However, some of the piping components 15 may be clogged or damaged by foreign matter inside the piping that flows together with the pressure-resistant water in the pressure resistance test, or the quality may be deteriorated by the cleaning liquid used for chemical cleaning. Therefore, in the present embodiment, the temporary pipe 2 is installed between two adjacent pipes instead of a part of the piping parts 15, and the two pipes 11 are connected by the temporary pipe 2. . According to the temporary pipe 2, it is not necessary to cut the pipe 11 after the chemical cleaning to be performed later, so that it is possible to eliminate the troubles and the possibility of contamination by the cutting. In addition, since the edges 12a and 13a of the pipe 11 can be protected, it is possible to eliminate the trouble of processing the groove in the pipe 11 again. Hereinafter, the temporary piping 2 will be described in detail with reference to FIGS. 2 and 3. 2 and 3 are a schematic perspective view and a cross-sectional view showing the temporary piping 2, respectively.

  As described above, the temporary pipe 2 is used to connect the pipes 11 between the adjacent pipes 11 when performing chemical cleaning inside the pipe 11 associated with the installation of the power plant 1. As shown in FIGS. 2 and 3, the temporary piping 2 includes a first flange portion 20 to which one piping 12 (see FIG. 5) is attached and a second flange portion to which another piping 13 (see FIG. 5) is attached. 40 and a pipe portion 30 provided between the first flange portion 20 and the second flange portion 40. The first flange portion 20, the tube portion 30, and the second flange portion 40 are arranged in this order along the axial direction d1 of the tube portion 30. In the illustrated example, the first flange portion 20 and the second flange portion 40 are formed in the same shape. Therefore, in the following description, the components common to the first flange portion 20 and the second flange portion 40 are indicated by omitting “first” or “second” and adding corresponding reference numerals. .

  As shown in FIG. 2, the flange parts 20 and 40 are comprised by the member of a hollow disk shape. The disk-shaped flange portions 20 and 40 include first surfaces 21 and 41 and second surfaces 22 and 42 facing the axial direction d1 of the tube portion 30. The pipes 12 and 13 are attached to the first surfaces 21 and 41. On the other hand, the second surfaces 22 and 42 face the other flange portions 40 and 20.

  In particular, the first surfaces 21, 41 of the flange portions 20, 40 are provided with recesses 23, 43 for receiving the edges 12 a, 13 a of the pipes 12, 13 that have been grooved. The recesses 23 and 43 are recessed from other portions of the first surfaces 21 and 41 from the first surfaces 21 and 41 toward the second surfaces 22 and 42. The concave portions 23 and 43 are formed corresponding to the edge portions 12 a and 13 a of the pipes 12 and 13. Typically, the edges 12a and 13a of the pipes 12 and 13 are formed in a cylindrical shape, and accordingly, the recesses 23 and 43 are formed in an annular shape.

  In consideration of workability, the edge portions 12a and 13a of the pipes 12 and 13 are inserted in the recessed portions 23 and 43 of the flange portions 20 and 40 with play. As will be described later, the first surfaces 21 and 41 of the flange portions 20 and 40 are connected to the pipe 12 in a state where the edge portions 12a and 13a of the pipes 12 and 13 are accommodated in the recesses 23 and 43 of the flange portions 20 and 40, respectively. , 13 can be welded to portions other than the edge portions 12a, 13a (see FIG. 7). As an example, the depth h1 of the recesses 23 and 43 is formed to be about 10 mm to 60 mm. However, the depth h1 of the recesses 23 and 43 can be set as appropriate according to the size and thickness of the pipes 12 and 13.

  Hollow spaces 24, 44 extending along the axial direction d1 of the tube portion 30 are formed in the center of the disk-shaped flange portions 20, 40, and one end of the tube portion 30 is inserted into the hollow spaces 24, 44. . The hollow spaces 24 and 44 pass through the flange portions 20 and 40, that is, extend from the first surfaces 21 and 41 to the second surfaces 22 and 42. In particular, in the present embodiment, the second surface 22 of the first flange portion 20 is a portion outside the hollow space 24 of the tube portion 30 in a state where the tube portion 30 is inserted into the hollow space 24 of the first flange portion 20. And is welded. In the example shown in FIG. 3, an annular weld bead wb is formed as a joint between the second surface 22 of the first flange portion 20 and the pipe portion 30.

  On the other hand, the second flange portion 40 is not fixed to the tube portion 30. For this reason, in a state in which the pipe portion 30 is inserted into the hollow space 44 of the second flange portion 40, the second flange portion 40 slides along the outer peripheral surface 31 of the pipe portion 30 and the shaft of the pipe portion 30. It is movable in the direction d1. With this configuration, the second flange portion 40 is movable relative to the first flange portion 20 and the pipe portion 30 in the axial direction d1. However, the second flange part 40 is fixed to the pipe part 30 when the two pipes 12 and 13 are connected between the two pipes 12 and 13 after installation. For this reason, the second surface 42 of the second flange portion 40 can be welded to a portion outside the hollow space 24 of the tube portion 30 in a state where the tube portion 30 is inserted into the hollow space 44 of the second flange portion 40. ing.

  Air vent holes 25 and 45 are formed around the hollow spaces 24 and 44 of the flange portions 20 and 40. The air vents 25 and 45 are provided for removing air and drain (pressure-resistant water and cleaning liquid) in the pipes 12 and 13 when the two pipes 12 and 13 are connected by the temporary pipe 2. The air vent holes 25 and 45 extend from the first surfaces 21 and 41 of the flange portions 20 and 40 to the second surfaces 22 and 42. Air vent holes 25 and 45 shown in FIG. 3 are connected to recesses 23 and 43 formed on the second surfaces 22 and 42, and partially overlap the recesses 23 and 43. As an example, a pipe for air bleeding (not shown) is connected to the air vent holes 25 and 45, and adjustment of air bleeding is performed by a valve (not shown) provided in the pipe for air bleeding.

  Next, the pipe part 30 extending between the first flange part 20 and the second flange part 40 will be described. As shown in FIG. 3, the pipe part 30 is comprised by the cylindrical member extended linearly in the axial direction d1. A hollow space 32 penetrating in the axial direction d1 is formed in the tube portion 30, and this hollow space 32 communicates with both the hollow space 24 of the first flange portion 20 and the hollow space 44 of the second flange portion 40. doing. In the present embodiment, the tube portion 30 is configured with such a length that each end portion of the tube portion 30 is accommodated in the hollow spaces 24 and 44 of the flange portions 20 and 40 located on the corresponding side. Yes. Thereby, when connecting two adjacent piping 12 and 13 by temporary piping 2, it can prevent that the edge part of the pipe part 30 contacts the piping 12 and 13 located in the corresponding side.

  In particular, in the pressure resistance test, the rigidity of the temporary piping 2 that can withstand the load of high-pressure pressure-resistant water is required. Considering this point, the thicknesses of the flange portions 20 and 40 and the tube portion 30 are determined. On the other hand, in the chemical cleaning, the size of the hollow space of the temporary pipe 2 that can sufficiently flow the cleaning liquid is required. Considering this point, the sizes of the hollow spaces 24 and 44 of the flange portions 20 and 40 and the hollow space 32 of the tube portion 30 are determined. That is, since the temporary piping 2 has a structure that can withstand use in both the pressure test and chemical cleaning, it is possible to save the trouble of removing the temporary piping 2 when moving from the pressure test to chemical cleaning.

  Next, a method of using the temporary pipe 2 configured as described above will be described with reference to FIGS. 4 to 10 are diagrams for explaining a method of using the temporary pipe 2, and FIG. 11 is a flowchart for explaining a pipe installation method of the power plant 1.

  First, as shown in FIG. 4, a plurality of pipes 11 and some pipe parts 15 are installed. However, the piping part 15 installed here is a part having a structure capable of withstanding a pressure test and chemical cleaning performed later. Next, as shown in FIG. 5, instead of the piping component 15 that has not been assembled, the temporary piping 2 is installed between two adjacent piping 12 and 13, and the two piping 12 and 13 are connected to each other. Connect with the temporary piping 2.

  The process of connecting the two pipes 12 and 13 with the temporary pipe 2 will be further described with reference to FIGS. First, as shown in FIG. 6, the second flange portion 40 is moved so as to approach the first flange portion 20 along the axial direction d <b> 1 of the pipe portion 30. Next, the temporary pipe 2 is installed between two adjacent pipes 12 and 13, and the edge 12 a of one pipe 12 is aligned with the recess 23 provided in the first flange portion 20 of the temporary pipe 2. Insert while. At this time, since the second flange portion 40 is brought close to the first flange portion 20 in advance, interference between the second flange portion 40 and the other pipes 13 can be avoided.

  Subsequently, in a state where the edge portion 12a of the one pipe 12 is accommodated in the concave portion 23 of the first flange portion 20, a portion other than the edge portion 12a of the one pipe 12 is formed on the first surface 21 of the first flange portion 20. Join. In particular, since the edge portion 12 a of the one pipe 12 is accommodated in the recess 23 of the first flange portion 20, the edge portion 12 a of the one pipe 12 can be protected by the first flange portion 20. In the example illustrated, a portion located around the hollow space 24 of the first surface 21 of the first flange portion 20 and a portion located outside the hollow space 24 of the outer peripheral surface of the one pipe 12 are: By welding in an annular shape, an annular weld bead wb is formed.

  Next, as shown in FIG. 7, the second flange portion 40 is moved away from the first flange portion 20 along the axial direction d1 of the tube portion 30. And the edge part 13a of the other piping 13 is accommodated in the recessed part 43 provided in the 2nd flange part 40, aligning. Thereafter, in a state where the edge portion 13a of the other pipe 13 is accommodated in the recess 43 of the second flange portion 40, a portion other than the edge portion 13a of the other pipe 13 is joined to the first surface 41 of the second flange portion 40. To do. In particular, since the edge 13a of the other pipe 13 is accommodated in the recess 43 of the second flange part 40, the edge 13a of the other pipe 13 can be protected by the second flange part 40. In the illustrated example, a portion located around the hollow space 44 of the first surface 41 of the second flange portion 40 and a portion located outside the hollow space 44 of the outer peripheral surface of the other pipe 13 are: By welding in an annular shape, an annular weld bead wb is formed.

  Thereafter, as shown in FIG. 8, pressure-resistant water is supplied into the pipes 11 to 13 and the temporary pipe 2. By connecting the two pipes 12 and 13 with the temporary pipe 2, the hollow space 12 b of one pipe 12 and the hollow space 13 b of the other pipe 13 are connected via the hollow spaces 22, 32 and 42 of the temporary pipe 2. Communicate. Therefore, the pressure-resistant water can pass between the two pipes 12 and 13 via the temporary pipe 2.

  Thereafter, the chemical cleaning liquid is caused to flow through the pipes 11 to 13 and the temporary pipe 2 while the temporary pipe 2 is attached. As the chemical cleaning liquid flows through the pipes 11 to 13, foreign matters such as rust and oils and fats in the pipes 11 to 13 are removed. In particular, in the present embodiment, the chemical cleaning liquid is caused to flow through the pipes 11 to 13 and the temporary pipe 2 without draining the supplied pressure-resistant water from the pipes 11 to 13 and the temporary pipe 2. In other words, the chemical cleaning liquid is caused to flow through the pipes 11 to 13 and the temporary pipes 11 to 13 while the supplied pressure-resistant water remains in the pipes 11 to 13 and the temporary pipe 2.

  After the chemical cleaning is completed, the temporary pipe 2 is removed from the pipes 12 and 13 as shown in FIG. In this Embodiment, the temporary piping 2 is removed by removing the weld bead wb which has joined the temporary piping 2 and each piping 12 and 13 using a grinder. After removing the temporary piping 2, as shown in FIG. 10, the remaining piping parts 15 are installed instead of the temporary piping 2. As described above, since the edge portions 12a and 13a of the pipes 12 and 13 are protected by the flange portions 20 and 40, a state in which a groove is formed at the edge portions 12a and 13a of the pipes 12 and 13 is maintained. ing. Therefore, the piping component 15 can be welded to the edge portions 12 a and 13 a of the pipes 12 and 13 without the need to process a groove in the edge portions 12 a and 13 a of the pipes 12 and 13. The piping component 15 installed here is a component that may be clogged or damaged by foreign matter inside the piping that flows together with the pressure-resistant water in the pressure resistance test, or the quality may be deteriorated by the cleaning liquid used for chemical cleaning. is there. As an example, a regulating valve, a safety valve, an orifice, a flow nozzle, or the like can be given.

  As described above, according to the temporary piping 2 of the present embodiment, the first flange portion 20 to which the one piping 12 having the edge 12a that has been grooved is attached and the second flange 13 to which the other piping 13 is attached. A flange portion 40; and a pipe portion 30 provided between the first flange portion 20 and the second flange portion 40, for accommodating the edge portion 12a of one pipe 12 in the first flange portion 20. The first flange portion 20 is a portion other than the edge portion 12a of the one pipe 12 in a state where the edge portion 12a of the one pipe 12 is accommodated in the recess portion 23 of the first flange portion 20. And can be welded. According to such a form, by accommodating the edge 12a of the one pipe 12 in the recess 23 of the first flange part 20, the edge 12a of the one pipe 12 that has been grooved is protected, The first flange portion 20 can be welded to a portion other than the edge portion 12a of the one pipe 12. For this reason, after chemical cleaning, the temporary pipe 2 is removed from the one pipe 12 without cutting the edge 12a of the one pipe 12, and the alternative pipe component 15 is not subjected to the groove processing on the edge 12a again. Can be welded to the edge 12a of one pipe 12 that has been grooved. As a result, it is possible to prevent the material of the pipe from being wasted along with the cutting, and to eliminate the possibility that foreign matter generated along with the cutting is mixed into the cleaned pipe. Furthermore, since it is not necessary to perform groove processing again on the edge portion 12a of the one pipe 12, work man-hours can be greatly reduced. From the above, according to the temporary piping 2 of the present embodiment, it is possible to easily perform chemical cleaning inside the piping.

  Moreover, according to this Embodiment, the recessed part 43 for accommodating the edge part 13a of the other pipe | tube 13 by which groove processing was carried out was provided in the 2nd flange part 40, and the recessed part of the 2nd flange part 40 is provided. In a state where the edge 13 a of the other pipe 13 is accommodated in 43, the second flange part 40 can be welded to a part other than the edge 13 a of the other pipe 13. According to such a form, by accommodating the edge 13a of the other pipe 13 in the recess 43 of the second flange 40, the edge 13a of the other pipe 13 that has been grooved is protected, The second flange portion 40 can be welded to a portion other than the edge portion 13a of the other pipe 13. For this reason, after chemical cleaning, the temporary piping 2 is removed from the other piping 13 without cutting the edge portion 13a of the other piping 13, and the edge portion 13a is not subjected to the groove processing again, and the alternative piping component 15 is removed. Can be welded to the edge 13a of the other pipe 13 that has been grooved. As a result, it is possible to prevent the material of the pipe from being wasted along with the cutting, and to eliminate the possibility that foreign matter generated along with the cutting is mixed into the cleaned pipe. Furthermore, since it is not necessary to perform groove processing on the edge 13a of the other pipe 13 again, the number of work steps can be greatly reduced.

  Moreover, according to this Embodiment, the 1st flange part 20 is being fixed with the pipe part 30, and the 2nd flange part 40 can move relatively with respect to the 1st flange part 20 and the pipe part 30. ing. According to such a configuration, when the one pipe 12 is welded to the first flange part 20, the second flange part 40 and the other pipe 13 are brought close to the first flange part 20. Interference with can be avoided. For this reason, the operation | work which welds the one piping 12 to the 1st flange part 20 can be performed easily. On the other hand, when welding the other pipe 13 to the second flange portion 40, the second flange portion 40 and the other pipe 13 are welded after the second flange portion 40 is brought close to the other pipe 13. Good. For this reason, the operation | work which welds the other piping 13 to the 2nd flange part 40 can also be performed easily.

  According to the present embodiment, the hollow space 44 extending in the axial direction d1 of the tube portion 30 is formed in the second flange portion 40, and the tube portion 30 is inserted into the hollow space 44. The part 40 slides along the outer peripheral surface 31 of the pipe part 30 and can move in the axial direction d1 of the pipe part 30. In this case, the second flange part 40 can be easily moved by sliding the second flange part 40 along the outer peripheral surface 31 of the pipe part 30.

  Moreover, according to the piping installation method of the power plant 1 of this Embodiment, the process of installing the some piping 11 which can be cleaned internally with a washing | cleaning liquid, and two adjacent piping 12 and 13 of the some piping 11 The temporary piping 2 is arranged between the two piping 12 and 13 by the temporary piping 2, the pressure water is supplied to the piping 11 and the temporary piping 2, and the piping 11 and the temporary piping 2 are chemically treated. A step of flowing the cleaning liquid, and a step of removing the temporary piping 2 and installing a piping component 15 in place of the temporary piping 2. According to such a piping installation method for the power plant 1, the above-described method for using the temporary piping 2 is provided. For this reason, it becomes possible to perform the piping installation work of the power plant 1 easily.

  Moreover, according to the piping installation method of the power plant 1 of this Embodiment, the said process to connect the edge part 12a of the one piping 12 to the recessed part 23 provided in the 1st flange part 20 of the temporary piping 2 is carried out. The process of accommodating and the process of welding the 1st flange part 20 with parts other than the edge part 12a of the one piping 12 in the state which accommodated the edge part 12a of the one piping 12 in the recessed part 23 of the 1st flange part 20. And including. According to such a form, since it becomes possible to remove the temporary piping 2 from the one piping 12 without cutting the one piping 12, the waste of the material cost of the piping accompanying the cutting can be reduced and the cutting can be performed. It is possible to eliminate the possibility that the accompanying foreign matter is mixed into the cleaned pipe. Furthermore, since the edge portion 12a of the one pipe 12 subjected to the groove processing is protected, it is possible to weld the piping component 15 to the edge portion 12a without performing the groove processing on the edge portion 12a again. it can. For this reason, piping parts, such as a regulating valve, can be easily welded to the edge 12a of one pipe 12.

  Further, according to the present embodiment, in the connecting step, the second flange portion 40 is brought closer to the first flange portion 20 along the axial direction d1 of the tube portion 30 prior to the accommodating step. And the second flange portion 40 is moved away from the first flange portion 20 along the axial direction d1 of the pipe portion 30, and the recess 43 provided in the second flange portion 40 is moved to the other. The step of accommodating the edge portion 13a of the pipe 13 and the state in which the edge portion 13a of the other pipe 13 is accommodated in the recess 43 of the second flange portion 40, the edge portion of the other pipe 13 And a step of welding with a portion other than 13a. According to such a form, the second flange portion 40 is brought close to the first flange portion 20, thereby avoiding interference between the second flange portion 40 and the other pipes 13, and one pipe on the first flange portion 20. 12 can be welded. For this reason, the operation | work which welds the one piping 12 to the 1st flange part 20 can be performed easily. Further, after welding one pipe 12, if the second flange part 40 is brought close to the other pipe 13, the other pipe 13 can be welded to the second flange part 40. For this reason, the operation | work which welds the other piping 13 to the 2nd flange part 40 can also be performed easily.

  By the way, in the chemical cleaning method using the closure cap described in the background art section, after welding the closure cap to the existing pipe before the pressure test, the temporary pipe is welded to the existing pipe instead of the closure cap before the chemical cleaning. Then, after chemical cleaning, piping parts were welded to existing pipes instead of temporary pipes. For this reason, parts were attached to the existing piping by welding three times in total, and the heat influence on the existing piping accompanying welding was large. On the other hand, according to the present embodiment, the temporary pipe 2 is welded to the existing pipes 12 and 13 before the pressure resistance test, and then the chemical cleaning is performed with the temporary pipe 2 being installed. Instead of the temporary pipe 2, a pipe part 15 is welded to the existing pipes 12 and 13. For this reason, the frequency | count of welding performed to the existing piping 12 and 13 can be reduced, and the thermal influence to the existing piping 12 and 13 accompanying welding can be suppressed.

  Further, according to the present embodiment, in the step of flowing the chemical cleaning liquid, the pressure water supplied in the step of supplying the pressure resistant water is not drained from the piping 11 and the temporary piping 2, and the piping 11 and The chemical cleaning liquid is caused to flow through the temporary pipe 2. In this case, since the process of draining the pressure-resistant water can be omitted, the piping installation work of the power plant 1 can be performed more efficiently.

  Note that various modifications can be made to the above-described embodiment. For example, in the above-described embodiment, as illustrated in FIG. 6, the example in which the length of the pipe portion 30 is set to a predetermined dimension in advance is shown, but the embodiment is not limited to such an example. In consideration of versatility, the length of the pipe portion 30 before the temporary pipe 2 is installed between the two pipes 12 and 13 is unified to a certain length, and the temporary pipe 2 is replaced with the two pipes 12. , 13, the pipe part 30 of the temporary pipe 2 may be cut to adjust the length of the pipe part 30 along the axial direction d1. That is, between the step of installing the plurality of pipes 11 and the step of connecting with the temporary pipe 2, the pipe part 30 of the temporary pipe 2 is cut, and the length along the axial direction d1 of the pipe part 30 is increased. You may further provide the process to adjust. In this case, the versatility of the temporary piping 2 is improved.

  In addition, embodiment is an illustration and the range of invention is not limited to it.

DESCRIPTION OF SYMBOLS 1 ... Power plant, 2 ... Temporary piping, 3 ... Boiler, 4 ... Steam turbine, 5 ... Generator, 6 ... Condenser, 7 ... Pump, 10 ... Circulation flow path, 11 ... Piping, 12 ... One piping, 12a ... Edge, 13 ... Other piping, 13a ... Edge, 15 ... Parts for piping, 20 ... First flange, 21 ... First surface, 22 ... Second surface, 23 ... Recess, 24 ... Hollow space, 25 ... Air vent hole, 30 ... Pipe portion, 31 ... Outer peripheral surface 31, 32 ... Hollow space, 40 ... Second flange portion, 41 ... First surface, 42 ... Second surface, 43 ... Recessed portion, 44 ... Hollow space, 45 ... Air venting hole, wb ... Welding bead, d1 ... Axial direction, 12b ... Hollow space of one pipe, 13b ... Hollow space of another pipe

Claims (9)

Temporary piping used to connect the pipes between adjacent pipes during chemical cleaning inside the pipes accompanying the installation of the power plant piping,
A first flange portion to which one pipe having a grooved edge is attached;
A second flange portion to which other piping is attached;
A pipe portion provided between the first flange portion and the second flange portion;
With
The first flange portion is provided with a recess for accommodating the edge of the one pipe,
Temporary piping in which the first flange portion can be welded to a portion other than the edge portion of the one pipe in a state where the edge portion of the one pipe is accommodated in the concave portion of the first flange portion. . The first flange portion is fixed to the pipe portion,
The temporary piping according to claim 1, wherein the second flange portion is movable relative to the first flange portion and the pipe portion. A hollow space extending in the axial direction of the tube portion is formed in the second flange portion, and the tube portion is inserted into the hollow space,
The temporary piping according to claim 2, wherein the second flange portion slides along an outer peripheral surface of the pipe portion and is movable in an axial direction of the pipe portion. The second flange portion is provided with a recess for receiving an edge of the other pipe that has been grooved,
The said 2nd flange part can be welded with parts other than the edge part of the said other piping in the state which accommodated the said edge part of the said other piping in the said recessed part of the said 2nd flange part. Temporary piping as described in any one of 1-3. A power plant piping installation method comprising:
Installing multiple pipes that can be cleaned internally with a cleaning solution;
A step of arranging the temporary pipe according to any one of claims 1 to 4 between two adjacent pipes of the plurality of pipes, and connecting the two pipes with the temporary pipe;
Supplying pressure-resistant water to the pipe and the temporary pipe;
Flowing chemical cleaning liquid to the pipe and the temporary pipe;
Removing the temporary piping and installing a piping component instead of the temporary piping;
A power plant piping installation method comprising: The step of connecting includes the step of accommodating the edge of the one pipe in the recess provided in the first flange part of the temporary pipe;
Welding the first flange portion with a portion other than the edge portion of the one pipe in a state where the edge portion of the one pipe is accommodated in the concave portion of the first flange portion;
The piping installation method of the power plant of Claim 5 containing this. The connecting step is a step of moving the second flange portion so as to approach the first flange portion along the axial direction of the pipe portion, prior to the accommodating step;
The second flange portion is moved away from the first flange portion along the axial direction of the pipe portion, and an edge portion of the other pipe is placed in a recess provided in the second flange portion. A housing process;
Welding the second flange portion with a portion other than the edge portion of the other pipe in a state where the edge portion of the other pipe is accommodated in the concave portion of the second flange portion;
The piping installation method of the power plant of Claim 6 which further contains these.   In the step of flowing the chemical cleaning liquid, the chemical cleaning liquid is caused to flow to the pipe and the temporary pipe without draining the pressure water supplied in the step of supplying the pressure water from the pipe and the temporary pipe. The piping installation method of the power plant as described in any one of Claims 5 thru | or 7.   Between the step of installing the plurality of pipes and the step of connecting, the method further includes a step of cutting the pipe part of the temporary pipe and adjusting a length along the axial direction of the pipe part. The piping installation method of the power plant as described in any one of Claims 5 thru | or 8.

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