JP2008106985A - Method of specifying leakage cooling tube of condenser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of immediately and surely specifying a leaking cooling tube of a condenser without stopping a turbine of an electric power plant. <P>SOLUTION: The method of specifying the leakage cooling tube of the condenser comprises a sea water draining process for draining sea water from the inlet and outlet side water chambers on one side or those on the other side of the condenser having two pairs of water chambers, a film sticking process for sticking a predetermined wrapping film to a tube opening of the cooling tube in a tube plate of the one or other inlet side water chamber or the one or other outlet side water chamber from which the sea water is drained; and a leakage determining process for determining that the cooling tube is the leaking tube when the shape of the wrapping film of the tube opening changes into a predetermined state. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for identifying a leakage cooling pipe of a condenser.

  Conventionally, thermal power plants and nuclear power plants have a water circulation system using a steam turbine coupled to a generator. In this circulation system, for example, water is heated by a boiler to form steam, and this steam is ejected to a steam turbine to rotate the turbine. And the steam after rotating a turbine is condensed by the condenser which uses seawater as cooling water, and is condensed. And this condensate is made into steam by being heated again in a boiler, and is again ejected to the steam turbine.

  As described above, the power plant condenses steam with a condenser using seawater as cooling water, and circulates the power plant using the condensed water as circulating water. For this reason, for example, when seawater leaks from a cooling pipe that is provided inside the condenser and circulates seawater, seawater enters the condenser, and seawater enters the condenser. There was a risk of causing corrosion of power plant components and piping. Therefore, in the above power plant, whether seawater is leaking inside the condenser is an important problem, and it is necessary to constantly monitor the presence or absence of seawater leakage. In addition, when seawater is mixed in the condensate, it was necessary to repair the cooling pipe that immediately leaked seawater.

  Here, the condenser is usually provided with a conductivity meter that measures the conductivity of the condensate in order to detect the mixing of seawater. When the condensate conductivity measured by this conductivity meter is equal to or higher than a predetermined threshold value, it is determined that seawater is mixed in the circulating water. For example, in a power plant, the value of conductivity measured by a conductivity meter can be set as a threshold value in a range of 0.3 μm / cm to 0.6 μm / cm. In the past, this conductivity meter was used to monitor the presence or absence of seawater.

  However, the mixing of seawater into the condenser can be confirmed by using, for example, a conductivity meter, but it has not been known where seawater has entered from the condenser. Specifically, it was not known which cooling pipe inside the condenser leaked seawater. Therefore, when contamination of seawater is detected by the conductivity meter, it is necessary to stop the turbine of the power plant once and specify the leakage cooling pipe by checking all the cooling pipes.

  Conventionally, the leakage cooling pipe has been specified by adding water to the extent that the cooling pipe is hidden inside the condenser. Specifically, the following confirmation work was performed. First, pure water is applied to the inside of the condenser body to such an extent that the cooling pipe disposed in the trunk part is submerged. Thereby, if there is a leaky cooling pipe, this pure water enters the leaky cooling pipe from a hole formed in the leaky cooling pipe. And since the pipe port of each cooling pipe penetrates to each of the inlet side and outlet side water chambers provided outside the fuselage, the pure water that has entered the cooling pipe from this pipe port It flows out to the inlet side or outlet side water chamber. The water chambers on the inlet side and the outlet side discharge the seawater supplied to the respective chambers in advance. Thus, the operator has confirmed that the said cooling pipe is a leaking cooling pipe by visually observing the pipe port which the pure water flowed out in each water chamber.

  However, in such a specific method, for example, if there is a large hole in the cooling pipe, it is easy to check because there is a large amount of pure water flowing out from the pipe port. Depending on the size of the hole, it may be difficult to confirm a small amount of pure water flowing out. Furthermore, it was very difficult to check tens of thousands of cooling pipes. In addition, this method has a problem in that a large amount of pure water is used, which is expensive.

  In contrast, a rubber plug provided with a central hole penetrating in the axial direction and a small hole having one end communicating with the central hole and the other end communicating with the outside is provided at the inlet of a cooling pipe to be inspected. A leak pipe detection method using a leak pipe detection device in which a pore and a manometer are connected via a pipe is disclosed (for example, see Patent Document 1).

  The detection method using the detection apparatus described in Patent Document 1 is to detect the pressure difference between the opening point of the pore provided in the rubber stopper and the opening point of the manometer with a manometer, and to check for leakage. is there. For example, when there is a broken hole in the cooling pipe and air leaks into the condenser, the static pressure at the opening point of the pore is lowered and a difference appears in the water column of the manometer. Thereby, it can be confirmed by the difference which arises in the water column of a manometer whether a cooling pipe has a broken hole.

JP 58-165030 A

  However, the detection method using the detection device described in Patent Document 1 tries to check for leakage by detecting a pressure difference between a predetermined opening point of the pore and a predetermined opening point of the manometer with a manometer. However, it has been very time consuming and laborious to carry out such work on tens of thousands of cooling pipes. In addition, the work has been lacking in convenience, for example, the pipe must be pulled out from the pores of the rubber stopper. Furthermore, this operation has to be performed by stopping the steam turbine of the power plant, and long-term power plant stoppage increases the loss of the plant.

  The present invention has been made in view of the above problems, and provides a method for identifying a leakage cooling pipe capable of quickly and reliably identifying a leakage cooling pipe of a condenser without stopping a turbine of a power plant. The purpose is to do.

  The inventor makes two pairs of water chambers provided in the condenser only one pair of operations (one-lung operation) and uses a lap sheet, while the steam turbine is operating. The present inventors have found that a leaky cooling pipe can be identified quickly and reliably, and have completed the present invention. Specifically, the following method for specifying the condenser cooling pipe is provided.

(1) Sea water used as cooling water for condensing steam discharged from the steam turbine, and one and the other cooling pipe groups composed of a plurality of cooling pipes, and a body part in which the cooling pipe groups are arranged The one and other inlet side water chambers for supplying the seawater to the cooling pipe, the one and other outlet side water chambers for receiving the seawater that has passed through the cooling pipe, and fixing both ends of the cooling pipe, A pair of tube plates that separate the body part from the one and the other inlet-side water chambers and the one and the other outlet-side water chambers, the one inlet-side water chamber being the one outlet A condenser connected to the side water chamber via the one cooling pipe group, and the other inlet side water chamber connected to the other outlet side water chamber via the other cooling pipe group Before the steam turbine is operating. A method of identifying a cooling pipe in which seawater is leaking,
A seawater discharging step of discharging the seawater from the one inlet side and one outlet side water chamber, or the other inlet side and other outlet side water chamber, and one or the other inlet side water discharging the seawater; A film sticking step of sticking a predetermined wrap film on the tube port of the cooling tube group in the tube plate of the one or the other outlet side water chamber from which the seawater is discharged, and the shape of the wrap film of the tube port And a leakage determining step of determining that the cooling pipe is a leakage pipe when the temperature changes to a predetermined state.

  According to the invention described in (1), the method for identifying the leakage cooling pipe of the condenser includes a seawater discharge step, a film sticking step, and a leakage determination step. Here, a film sticking process sticks a predetermined | prescribed wrap film to the tube opening of the said cooling pipe in the said tube plate of the 1st or 2nd inlet side and the outlet side water chamber which discharged | emitted seawater. The condenser is provided with first and second water chambers on the inlet side and the outlet side, respectively, and the film sticking step is performed on either the first or second water chamber on each of the inlet side and the outlet side. Use either one. Thereby, it is possible to work without stopping the steam turbine. In addition, when the steam turbine is in operation, the condenser is usually kept in vacuum, so the suction force from the leak cooling pipe port based on the pressure difference is large, and the wrap film can be easily attached to the tube sheet. Can be made. In addition, by using a wrap film of a predetermined thickness, it becomes possible to easily rupture the wrap film applied to the leakage cooling pipe by a suction force. Can do.

  (2) Between the seawater discharging step and the film pasting step, the seawater is discharged from one or the other inlet-side water chamber, or the seawater is discharged from the one or the other outlet-side water chamber. A soap film is applied to the tube plate and a soap film is formed on the tube port of the cooling tube group on the tube plate, and a soap film is stretched on the tube port of the cooling tube group to which the soap solution is applied. A leak pipe estimation step for estimating that the leak pipe is not present, and the film sticking step sticks the wrap film to the pipe port of the cooling pipe estimated as the leak pipe in the leak pipe estimation step. (1) The method for identifying a condenser cooling pipe according to (1).

  According to the invention described in (2), the method for specifying the leakage cooling pipe of the condenser further includes a soap film formation process and a leakage pipe estimation process between the seawater discharge process and the film sticking process. Here, the soap film forming step applies a soap solution to the tube plate of the first or second inlet-side water chamber or the first or second outlet-side water chamber from which seawater has been discharged by the seawater discharging step, and the inlet A soap film is formed at each side of the side pipe opening or the outlet side cooling pipe. Thus, for example, it is possible to estimate the leakage cooling pipe by performing the soap film forming step while using the same specific method as described above. As a result, for example, it is possible to efficiently identify the step for checking the leakage cooling pipe, that is, the leakage cooling pipe, and to reduce the substantial inspection effort of the cooling pipe. Moreover, by applying the soap solution to the tube plate, for example, it becomes easy to apply the wrap film in the film applying step to the tube plate.

  (3) The leakage determination step according to (1) or (2), wherein at least the wrap film is sucked inside the cooling tube or is judged to be a leakage tube when torn by suction. A method for identifying condenser condenser leak condensers.

  According to the invention described in (3), the leakage determination step determines that the wrap film is a leakage cooling pipe when the shape of the wrap film is deformed to a predetermined shape. For example, when the wrap film is pulled into the cooling pipe and deformed into a concave shape, or the wrap film is torn, it can be determined that it is a leaky cooling pipe. Thereby, for example, since the wrap film is significantly deformed, the operator's visual judgment becomes easy.

  (4) The method for identifying a leakage cooling pipe of a condenser according to any one of (1) to (3), wherein the wrap film is formed of a polyvinylidene chloride resin.

  According to the invention described in (4), the wrap film is formed of a polyvinylidene chloride resin. Thereby, a wrap film is provided with predetermined adhesiveness, for example, and can improve workability | operativity.

  (5) The method for identifying a leakage cooling pipe of a condenser according to any one of (1) to (4), wherein the wrap film has a thickness of 11 μm or less.

  According to the invention described in (5), a wrap film having a thickness of 11 μm or less is used. Thereby, since the wrap film has, for example, tear strength and has a predetermined ease of being cut, leakage of the cooling pipe can be reliably determined.

  ADVANTAGE OF THE INVENTION According to this invention, the leaking cooling pipe of a condenser can be pinpointed quickly and reliably, without stopping the turbine of a power plant.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, embodiment of this invention is not limited to the following embodiment at all, and the technical scope of this invention is not limited to this.

  FIG. 1 is a schematic diagram showing a system configuration of a thermal power plant according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the configuration of the condenser according to the present invention. FIG. 3 is a flowchart showing a method for specifying a leakage cooling pipe of a condenser according to the present invention. FIG. 4 is an enlarged partial sectional view showing a leakage cooling pipe of a condenser to which a soap solution is applied. FIG. 5 is an enlarged partial sectional view showing a leakage cooling pipe of a condenser to which a wrap sheet is pasted after applying a soap solution.

  First, the thermal power plant according to the present embodiment shown in FIG. 1 will be described. As shown in FIG. 1, the thermal power plant according to the present embodiment is roughly composed of a steam turbine system, a condensate / water supply system, and a steam generator system.

  The steam turbine system includes a high pressure steam turbine 2, an intermediate pressure steam turbine 3, and a low pressure steam turbine 4. These steam turbine systems are supplied with steam heated by a steam generator system to be described later. In the present embodiment, the high-pressure steam turbine 2, the intermediate-pressure steam turbine 3, and the low-pressure steam turbine 4 are connected to a drive shaft on one shaft, and the generator 5 connected to the drive shaft is driven to generate electric power. Is occurring.

  The condensate / water supply system was condensed by a condenser 6 that condenses the steam that has finished work in the low-pressure steam turbine 4 by heat exchange with the seawater W used as cooling water, and the condenser 6. And a water supply pipe 15 for supplying the condensate to the exhaust heat recovery boiler system. Here, the steam that has finished work in the low-pressure steam turbine 4 is provided in the body portion 60 of the condenser 6 and passes between the nests of the plurality of cooling pipes 63 in which the seawater W flows. It is condensed by.

  The condensate condensed in the condenser 6 is accumulated in the condensate retention part 65 in the condenser 6 and is sent to the condensate pump 6P from the condenser outlet 66 provided at the lower part of the condenser 6 to increase the pressure. Is done. The condensate whose pressure has been increased by the condensate pump 6P passes through the condensate stop valve 6V, the condensate demineralizer 31, the ground steam condenser 9, and the feed water stop valve 15V, and then the boiler supply pump 1P and the exhaust heat recovery boiler. 1 respectively. Further, when there is excess water in the system, it is recovered from the recovery pipe 17 to the condensate tank 17T by controlling the discharge flow rate adjusting valve 17V provided in the water supply pipe 15. The recovery pipe 17 is connected to the condenser 6 via a condensate tank 17T, and the water remaining in the system is supplied to the condenser 6 as appropriate.

  The condenser 6 is connected to a makeup water pipe 18 for supplying makeup water to the condenser 6. A makeup water tank 7 is connected to the makeup water pipe 18 via a makeup water supply valve 7V and a makeup water pump 7P. The makeup water pipe 18 is connected to a makeup water pipe 16 for supplying makeup water supplied by the makeup water pump 7P to the downstream side of the feed water stop valve 15V installed in the feed water pipe 15. 16 is provided with a makeup water valve 16V. A chemical storage tank 8 in which chemicals or chemical dilution water is stored is connected to the water supply pipe 15 via a chemical supply pipe 19. The chemical supply pipe 19 is provided with a chemical transfer pump 8P for supplying chemical dilution water and a flow rate adjusting valve 8V for adjusting the flow rate of the chemical dilution water. In this embodiment, the injection point of the chemical dilution water is installed on the AC side of the water supply stop valve 15V, but may be installed in the water supply pipe 15 upstream of the water supply stop valve 15V. Moreover, you may install so that it may inject | pour into the boiler drum (not shown) of the waste heat recovery boiler 1. FIG.

  In the exhaust heat recovery boiler 1 which is a steam generator system, for example, steam is generated using high-temperature exhaust heat exhausted from a gas turbine (not shown). The condensate supplied by the boiler supply pump 1 </ b> P is heated by the exhaust heat recovery boiler 1 to become steam, and the generated steam flows through the main steam pipe 10 and flows into the high-pressure steam turbine 2. Further, the steam discharged from the high pressure steam turbine 2 flows through the high pressure turbine discharge pipe, is mixed with the medium pressure steam, and is heated again by the reheater (not shown) of the exhaust heat recovery boiler 1. The steam reheated by the reheater flows through the reheat steam pipe 11 and flows into the intermediate pressure steam turbine 3. On the other hand, the low pressure steam heated by the exhaust heat recovery boiler 1 flows into the intermediate pressure steam turbine 3 through the low pressure steam pipe 12. The steam flowing into the intermediate pressure steam turbine 3 through the low pressure steam pipe 12 is mixed to become low pressure steam, and further flows into the low pressure steam turbine 4. Further, a high-pressure steam bypass pipe 13 and an intermediate-pressure steam bypass pipe 14 are connected to the main steam pipe 10 and the low-pressure steam pipe 12, respectively, and steam generated in the exhaust heat recovery boiler 1 by these bypass pipes is condensate. Is supplied to the vessel 6.

  Here, the condenser 6 shown in FIG. 2 will be described. As shown in FIG. 2, the condenser 6 according to the present embodiment includes a body portion 60, first and second inlet-side water chambers 61 </ b> A and 61 </ b> B provided on one side of the body portion 60, and a body portion. 1st and 2nd exit side water chamber 62A, 62B provided in the other side of 60. Specifically, a first inlet-side water chamber 61A and a second inlet-side water chamber 61B are disposed on the inlet side, which is one side of the condenser 6 to which seawater W used as cooling water is supplied. The Moreover, 62 A of 1st exit side water chambers and the 2nd exit side water chamber 62B are arrange | positioned at the exit side from which the seawater W is discharged | emitted. A plurality of cooling pipes 63, 63,... Are arranged in parallel inside the body portion 60, forming a tube nest composed of a first cooling pipe group and a second cooling pipe group.

  One end of the plurality of cooling pipes 63 made of the first cooling pipe group opens into the first inlet-side water chamber 61A via the tube plate 64, and the other end of the first outlet-side water chamber 62A via the tube plate 64. Open in. One end of the cooling pipe 63 made of the second cooling pipe group opens into the second inlet-side water chamber 61B via the tube plate 64, and the other end of the second outlet-side water chamber 62B via the tube plate 64. Open in. That is, the first inlet-side water chamber 61A is connected to the first outlet-side water chamber 62A via the cooling pipe 63 made of the first cooling pipe group, and the second inlet-side water chamber 61B is connected to the second cooling pipe. It is connected to the second outlet side water chamber 62B via a cooling pipe 63 made of a group.

  Here, the tube sheet 64 isolates the trunk | drum 60 and each water chamber 61A, 61B, 62A, 62B. Cooling water inlet pipes 67 and 67 having cooling water supply valves 67V and 67V are connected to the first and second inlet side water chambers 61A and 61B, respectively. Further, cooling water discharge pipes 68 and 68 having cooling water discharge valves 68V and 68V are connected to the first and second outlet side water chambers 62A and 62B.

  A condensate retention part 65 is provided at the lower part of the condenser 6, and condensed condensate is stored here. Furthermore, a condenser outlet 66 is provided at the bottom of the condensate retention part 65, and the condensate is supplied again to the exhaust heat recovery boiler 1 via a water supply pipe 15 provided with a supply stop valve 15V. Circulates within the power plant. Here, the condensate retention part 65 causes the partition plate 70 to retain the first retention part 65A for retaining the condensed water condensed by the first cooling pipe group and the condensed water condensed by the second cooling pipe group. It is partitioned off from the second staying part 65B. The bottom portions of the first and second retention portions 65A and 65B are provided with salinometers 69 and 69 for checking the salinity in the seawater W. By monitoring the salinity of the condensate, the cooling pipe Determine leaks. Thus, by providing the salt meter 69, 69 at the bottom of each of the first and second retention portions 65A, 65B, the operator can check the first salt meter 69, 69 by first checking the salt meter 69, 69. Alternatively, it can be estimated which side of the second cooling pipe group is leaking.

  Next, a specific embodiment of the condenser 6 shown in FIG. 2 will be described with reference to FIG. The steam exhausted from the steam turbine system flows into the body portion 60 of the condenser 6 from above the condenser 6. The steam that has flowed into the body portion 60 undergoes heat exchange by passing between the nests of the cooling pipe 63 that is the heat transfer pipe through which the seawater W that is the cooling water flows. The heat-exchanged steam is condensed and becomes condensate, which is dropped into the condensate retention part 65. The dropped condensate stays in the condensate retention part 65, flows through the bottom surface inclined toward the condenser outlet 66, and flows out of the condenser 6.

  Here, the condenser 6 has a first detection water outlet (not shown) and a second detection water outlet (not shown) in the first and second retention portions 65A and 65B, which are the condensate retention portion 65 where the condensate drops. A third detection water outlet (not shown) and a third detection water outlet (not shown) are provided. The first detection water outlet is installed at a position directly below the tube nest, for example, at a location where the first detection water drops and first stays, or in the vicinity thereof. Further, the second detection water outlet (not shown) is arranged at or near the condenser outlet 66 from which the accumulated condensate is discharged. Further, the third detection water outlet (not shown) is provided with a first detection water outlet provided in the vicinity of the first and second retention portions 65A and 65B where the condensate drops, and the retained condensate is discharged. It is arrange | positioned in the substantially intermediate | middle position with the 2nd detection water intake provided in the vicinity of the condenser outlet 66 which is. Thus, the condenser 6 according to the present embodiment is located upstream and downstream of the first and second retention portions 65A and 65B, and from the upstream side to the downstream side of the first and second retention portions 65A and 65B. By performing a water quality test from each detected water outlet at a substantially intermediate position of the flow channel that flows toward, for example, the measurement conditions of the condensate are made to be close to a certain level, so that more accurate and stable leakage of seawater W can be achieved. It is possible to perform detection.

  In this embodiment, the medicine storage tank 8 in which medicine or medicine dilution water is stored, the medicine supply pipe 19 that guides the medicine or medicine dilution water to the water supply pipe 15, and the medicine supply pipe 19 are installed in the medicine or A chemical transfer pump 8P that transfers chemical dilution water to the water supply pipe 15 and a flow rate adjustment valve 8V that adjusts the flow rate of the chemical or chemical dilution water supplied to the water supply pipe 15 are provided. Thereby, for example, when the leakage of the seawater W is small, the chemical or the chemical dilution water can be supplied to the water supply pipe 15.

  Next, a method for specifying the leakage cooling pipe of the condenser 6 according to the present invention will be described with reference to the flowchart shown in FIG.

  As shown in FIG. 3, first, in the monitoring by the salt detection device provided in the control device (not shown) of the condenser 6, the conductivity value is confirmed. Specifically, it is confirmed whether or not the numerical value of the conductivity meter is higher than a predetermined numerical value, for example, whether or not it is higher than a numerical value set as a threshold value (step S10). Here, when the numerical value of the conductivity is higher than a predetermined threshold value, that is, when the salt detection device shows an abnormality (step S15), the salt meter 69, 69 provided at the lower portion of the condenser 6 is used. Is confirmed (step S20). When the values of the salometers 69 and 69 do not indicate a normal numerical range (step S25), a seawater valve (not shown) connected to the first (second) inlet-side water chamber 61A (61B). Is cut (step S30), and the inflow of the seawater W is stopped. Next, the cooling water supply valves 67V and 67V and the cooling water discharge valves 68V and 68V are released, and the first (second) inlet side water chamber 61A (61B) is connected to the cooling water inlet pipes 67 and 67 and the cooling water discharge pipes 68 and 68. ) And the first (second) outlet-side water chamber 62A (62B) are discharged (step S35).

  Next, the manhole covers of the first (second) inlet-side water chamber 61A (61B) and the first (second) outlet-side water chamber 62A (62B) are opened to release the chamber and to measure oxygen deficiency and hydrogen sulfide. And the inside of the first (second) inlet-side water chamber 61A (61B) and the first (second) outlet-side water chamber 62A (62B) is ventilated (step S40). Next, the inside of the cooling pipe 63 is air flushed to discharge excess water droplets (step S45).

  Here, the soap solution 20 is applied to the tube port 64a of the cooling tube group disposed in the tube plate 64 of the first (second) inlet-side water chamber 61A (61B) (step S50). Thereby, a soap film 20 'is formed. Here, during operation of the thermal power plant, the inside of the fuselage portion 60 of the condenser 6 is kept in a vacuum state, so that a broken hole is generated in the cooling pipe 63 disposed inside the fuselage portion 60. In this case, the air in the leakage cooling pipe 63 ′ is pulled into the body portion of the condenser 6 from the broken hole due to the decrease in internal pressure. Thereby, the air in the vicinity of the pipe port 64a is also pulled. Therefore, when the soap film 20 ′ is formed at the pipe port 64 a of the cooling pipe 63, the soap film 20 ′ formed at the pipe port 64 a ′ is ruptured 21 in the case of the leakage cooling pipe 63 ′. In this way, the possibility of leakage of the cooling pipe 63 can be estimated.

  Note that the soap solution 20 used in the present embodiment needs to use a soap solution 20 in which the soap film 20 ′ formed on the surface of the cooling pipe port 64a is not easily broken because it is necessary to inspect a wide area in a short time. is there. Therefore, in this embodiment, a liquid A in which 160 ml of water and 54 g of sugar are mixed, a liquid B in which 160 ml of water, 340 ml of a synthetic detergent (surfactant) and 180 ml of glycerin are mixed are respectively prepared. Soap solution 20 made by mixing B and solution B was used. Thereby, the soap liquid 20 with certainty and durability can be produced on the surface of the cooling pipe opening 64a to be inspected.

  It is confirmed whether or not a soap film 20 'is formed on each of the pipe ports 64a to which the soap liquid 20 is applied (step S55). Here, for example, as shown in FIG. 4, when a pipe port 64a ′ in which the soap film 20 ′ is not formed is found, the location of the pipe port 64a ′ is confirmed and specified (step S65). . Even when the soap film 20 'is formed, if the film is cracked immediately thereafter, there is a possibility of leakage, so the location is also confirmed and specified (step S60). Note that the tube port 64a is preferably specified by dividing the tube plate 64 into each area and inspecting and specifying each area.

  Next, when confirmation by application of the soap solution 20 is completed in all areas of the tube plate 64, the wrap film 21 is attached to the tube port 64a 'specified at the time of application of the soap solution 20 (step S70). Here, it is preferable to divide the vicinity of the pipe opening 64a 'identified in step S65 for each area, and to perform work using, for example, a wrap film having a size of 1 m in length and 1.5 m in width. In addition, since the soap solution 20 is applied to the tube plate 64 in step S50, the wrap film 21 is in a state of being easily attached to the tube plate 64. Further, for example, in the leakage cooling pipe 63 ′, a suction force due to the internal pressure difference is further generated in the pipe port 64a ′, so that the wrap film 21 can be attached to the pipe port 64a ′ only by applying the wrap film 21. Therefore, workability is improved.

  If there is a broken hole in the cooling pipe, for example, as shown in FIG. 5, the interior of the body 60 of the condenser 6 is kept in a vacuum, and is attached to the pipe port 64a ′ in step S70. The wrap film 21 is pulled into the cooling pipe and deformed into a concave shape or ruptures. In addition, as the wrap film 21 used for a present Example, it is preferable that it is a wrap film whose film thickness is 11 micrometers or less, for example. It is because it is easy to burst when pulled by a vacuum. Moreover, it is preferable that it is a wrap film made from polyvinylidene chloride. That is, as the wrap film, for example, Saran Wrap (registered trademark) can be used.

  The operator confirms whether the attached wrap film 21 is ruptured or deformed. Usually, the wrap film 21 is readily ruptured by a tensile force due to an internal pressure difference, so that confirmation is easy. For example, when the puncture is small, the wrap film 21 may remain until it is deformed into a concave shape without being ruptured. However, in any case, such a change in the state of the wrap film 21 can be easily performed visually.

  If rupture or deformation of the wrap film 21 is confirmed at the pipe port 64a ′ (step S75, step S80), the cooling pipe can be identified as the leakage cooling pipe 63 ′, and therefore the inlet side of the leakage cooling pipe 63 ′. A plug is attached to each of the outlets 64a 'on the outlet side (step 85).

  Note that only a specific method using the soap film 20 ′ formed by the soap liquid 20 can be used, but since the film may be ruptured by the atmosphere and flow of air or the like, the soap film 20 ′ can be more reliably cooled by leakage. In order to specify the tube, it is preferable to specify using a wrap film 21 in addition to the method using the soap solution 20. Moreover, in the case of the method specified using the wrap film 21, application | coating of the soap liquid 20 is used in order to improve the adhesiveness of the wrap film 21, for example besides formation of the said soap film | membrane 20 '. Also good.

  Thus, in the condenser 6 having two pairs of water chambers 61A, 61B, 62A, 62B, one pair is used for condensing steam by operating the steam turbine, and the other pair is used for checking the leakage cooling pipe 63 ′. It is possible to identify (inspect) the leakage cooling pipe without stopping the steam turbine. Further, since the steam turbine is in operation, the inside of the fuselage portion 60 of the condenser 6 is in a vacuum, so that leakage occurs by using a wrap film 21 (for example, Saran Wrap (registered trademark)) having a predetermined thickness. Since the wrap film 21 affixed to the pipe port 64a ′ of the cooling pipe 63 ′ is ruptured or deformed, the leakage cooling pipe 63 ′ can be easily confirmed, and the specific misidentification of the leakage cooling pipe 63 ′ can be reduced. Moreover, since the inside of the trunk | drum 60 of the condenser 6 is hold | maintained in vacuum, when inspecting from one side, it can identify, for example, without carrying out a cover etc. with respect to the other side pipe port.

It is the schematic which shows the system configuration | structure of the thermal power plant which concerns on the Example of this invention. It is the schematic which shows the structure of the condenser which concerns on this invention. It is a flowchart which shows the identification method of the leakage cooling pipe of the condenser which concerns on this invention. It is an expanded partial sectional view which shows the leakage cooling pipe of the condenser which apply | coated with the soap liquid. It is an expanded partial sectional view which shows the leaking cooling pipe of the condenser which stuck the wrap sheet | seat after apply | coating with a soap liquid.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waste heat recovery boiler 2 High pressure steam turbine 3 Medium pressure steam turbine 4 Low pressure steam turbine 5 Generator 6 Condenser 6P Condensate pump 7 Supply water tank 7P Supply water pump 8 Chemical storage tank 8P Chemical transfer pump 60 Body 61A 1st 1 inlet side water chamber 61B second inlet side water chamber 62A first outlet side water chamber 62B second outlet side water chamber 63 cooling pipe 64 tube plate 64a pipe port 65 condensate retention part 66 condenser outlet 67, 67 cooling water Inlet pipe 68, 68 Cooling water discharge pipe 69, 69 Salt meter W Seawater

Claims (5)

Sea water used as cooling water for condensing steam discharged from the steam turbine is passed, one and the other cooling pipe group consisting of a plurality of cooling pipes, a body part in which the cooling pipe group is disposed, and the cooling One and other inlet-side water chambers for supplying the seawater to the pipe, one and other outlet-side water chambers for receiving the seawater that has passed through the cooling pipe, and fixing both ends of the cooling pipe; A pair of tube plates that isolate the one and the other inlet-side water chambers and the one and the other outlet-side water chambers,
The one inlet-side water chamber is connected to the one outlet-side water chamber via the one cooling pipe group, and the other inlet-side water chamber is connected to the other outlet-side water chamber and the other Among the cooling pipes of the condenser connected through the cooling pipe group, a method of identifying a cooling pipe in which the seawater is leaking while the steam turbine is operating,
A seawater discharge step of discharging the seawater from the one inlet side and one outlet side water chamber, or the other inlet side and other outlet side water chamber;
A film for sticking a predetermined wrap film to one or the other inlet-side water chamber from which the seawater has been discharged or one of the outlet plates of the cooling water in the tube plate of the one or other outlet-side water chamber from which the seawater has been discharged Pasting process,
A leakage determining pipe identifying method for a condenser, comprising: a leakage determining step of determining that the cooling pipe is a leakage pipe when the shape of the wrap film at the pipe opening changes to a predetermined state. Between the seawater discharge step and the film sticking step,
Applying a soap solution to one or the other inlet-side water chamber from which the seawater has been discharged or one or the other outlet-side water chamber from which the seawater has been discharged is applied to the cooling tube group in the tube plate. A soap film forming step of forming a soap film at the pipe opening;
A leak pipe estimation step for estimating a leak pipe by not forming a soap film on the mouth of the cooling pipe group to which the soap liquid is applied, and
The method for identifying a leaking cooling pipe of a condenser according to claim 1, wherein the film sticking step attaches the wrap film to the pipe opening of the cooling pipe estimated as the leaking pipe in the leaking pipe estimation step.   The leak of the condenser according to claim 1 or 2, wherein the leakage determination step determines that the wrap film is a leakage pipe when at least the wrap film is sucked into the cooling pipe or is torn by suction. How to identify the cooling pipe.   The method for identifying a condenser cooling pipe of a condenser according to any one of claims 1 to 3, wherein the wrap film is formed of a polyvinylidene chloride resin.   The method for identifying a condenser cooling pipe of a condenser according to claim 1, wherein the wrap film has a thickness of 11 μm or less.

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