JP2007198174A - Water shut-off device for draft tube and method for installing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water shut-off device for a draft tube which has a simple structure, can be easily installed and has stable sealing performance. <P>SOLUTION: The water shut-off device 1 for the draft tube is installed in the draft tube D for introducing draft water from a Francis turbine T to a flood way R, shuts off the water of the draft tube D, and is provided with a partition plate 3 partitioning the inside of the draft tube D into a Francis turbine T side and the flood way R side, and an annular tube 2 inflates and seals a part between the inner circumference surface of the draft tube D and the partition plate 3 when air is filled therein and presses the inner circumference surface of the draft tube D to retain the partition plate 3 in the draft tube D. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a water stop device for stopping a suction pipe (draft pipe) when inspecting and maintaining the inside of a turbine or power generation facility in a hydroelectric power plant or the like.

  In hydroelectric power plants and the like, suction pipes (draft pipes) are installed to guide the sucked water from the water turbines to the discharge channel. Since water may flow (reverse flow) from the downstream side (water discharge channel side) to the water turbine side via this suction pipe, it is necessary to stop the suction pipe when inspecting and maintaining the inside of the water turbine. is there. Conventionally, an iron plate was welded in the suction pipe as a water stop method. However, repeated welding has a thermal effect on the base material of the suction pipe, and the workability is poor because the welding work is performed in the narrow suction pipe. The welding quality was also unstable. For this reason, the water stop apparatus which stops a suction pipe not depending on welding is known (for example, refer patent document 1).

This water stop device seals the space between the beam member fixed in the suction pipe, the tread board fixed to the beam member and dividing the inside of the suction pipe up and down, and the inner peripheral surface of the suction pipe and the suction pipe. And a sealing portion to be stopped. Further, the seal portion includes a plurality of pressing members and a pressing mechanism, and a sealing material is disposed between the pressing member and the inner peripheral surface of the suction pipe, and the pressing member is disposed on the inner peripheral surface side of the suction pipe by the pressing mechanism. By pressing, the sealing material is pressed and the space between the tread board and the inner peripheral surface of the suction pipe is sealed. On the other hand, it is necessary to form a concave beam support portion on the inner wall of the suction pipe in order to fix the beam member. And in order to install such a water stop apparatus in a suction pipe, the beam member divided | segmented into several is carried in in a suction pipe, and each beam member is each connected, fixing a beam member to a beam support part. Next, the divided treads are carried into the suction pipe, each tread is fixed to the beam member, and the plurality of pressing members are attached to the tread. Furthermore, a sealing material is disposed between the pressing member and the inner peripheral surface of the suction pipe, and each pressing member is pressed against the inner peripheral surface side of the suction pipe by each pressing mechanism.
JP 2000-230472 A

  By the way, in the water stop apparatus as described in the said patent document 1, not only many components and a structure are complicated, but much time and labor are required for installation. That is, in order to install the water stop device, many members such as a beam member and a pressing member must be carried into the suction pipe and assembled, and the workability is improved because it is an installation work in a narrow suction pipe. Unfortunately, it takes a lot of time and effort to install. Furthermore, since a beam support portion is required on the inner wall of the suction pipe, it is necessary to process (construct) the existing suction pipe itself. Further, since the sealing material is pressed against the inner peripheral surface of the suction pipe by a plurality of pressing mechanisms and pressing members, if the pressing force by each pressing mechanism is not uniform, the sealing performance (water tightness) by the sealing material is also uniform. However, it is difficult to make the pressing force by each pressing mechanism uniform, and there is an unstable factor in the sealing performance of the water stop device.

  Accordingly, an object of the present invention is to provide a water stop device for a suction pipe that is easy to install with a simple configuration (structure) and has a stable sealing property.

In order to achieve the above-mentioned object, the invention according to claim 1 is provided inside a suction pipe for guiding the sucked water from the water turbine to the water discharge channel, and is a water stop device for the suction pipe for stopping the suction pipe. A partition portion that divides the inside of the suction pipe into the water wheel side and the water discharge passage side, and expands when gas is introduced to seal between the partition portion and the inner peripheral surface of the suction pipe; And a seal portion that presses an inner peripheral surface to hold the partition portion in the suction pipe.
(Function)
The inside of the suction pipe is partitioned by the partition part, and the space between the partition part and the inner peripheral surface of the suction pipe is sealed by putting gas into the seal part. At the same time, the seal part presses the inner peripheral surface of the suction pipe, the partition part is held in the suction pipe by the seal part, and the suction pipe is stopped by the partition part and the seal part.

According to a second aspect of the present invention, in the water stop device for the suction pipe according to the first aspect, the seal portion is formed in an annular shape, and a plate-like partition portion is disposed so as to close the inside of the seal portion. It is characterized by having.
(Function)
The plate-like partition portion blocks the inflow of water from the ring of the seal portion, and the seal portion seals between the partition portion and the inner peripheral surface of the suction pipe.

According to a third aspect of the present invention, in the water stop device for a suction pipe according to the second aspect, the partition portion is formed to be foldable.
(Function)
When installing the water stop device for the suction pipe in the suction pipe, the partition is extended (expanded), and when the water stop device for the suction pipe is not used, the partition is folded.

According to a fourth aspect of the present invention, the suction pipe water stop device according to any one of the first to third aspects is installed inside the suction pipe for guiding the sucked water from the water turbine to the water discharge channel. An installation method is characterized in that the partition portion is positioned so as to come into contact with the surface of the work scaffold installed in the suction pipe on the side of the water discharge channel, and gas is introduced into the seal portion.
(Function)
When the partition is positioned so as to abut the surface (lower surface) of the work scaffold on the side of the spillway and gas is introduced into the seal, the seal expands and the space between the partition and the inner peripheral surface of the suction pipe is sealed. The At the same time, the seal portion presses the inner peripheral surface of the suction pipe, and the partition portion is held in the suction pipe by the seal portion. Thereby, the water stop apparatus for suction pipes is installed so that it may contact | abut to the surface by the side of the water discharge channel of a work scaffold.

  According to the first aspect of the present invention, the water stop device for the suction pipe has a simple configuration including the partition part and the seal part, and the suction pipe is stopped by the partition part and the seal part by introducing gas into the seal part. Watered. In addition, since the partition portion is held in the suction pipe simply by putting gas into the seal portion, that is, the suction pipe water stop device is installed in the suction pipe, the installation of the suction pipe water stop device becomes extremely easy. In addition, when gas is introduced, the seal portion expands and the space between the partition portion and the inner peripheral surface of the suction pipe is sealed (sealed), that is, sealed by the gas pressure (hydrostatic pressure). The space between the inner peripheral surface of the tube can be uniformly and stably sealed.

  According to invention of Claim 2, since the plate-shaped partition part is arrange | positioned so that the inside of the ring | ring of a seal | sticker part may be block | closed, a partition part can be utilized as a scaffold board, etc. Inspection and maintenance can be performed easily and safely.

  According to invention of Claim 3, when not using the water stop apparatus for suction pipes, it can convey the water stop apparatus for suction pipes in a compact state by extracting gas from the inside of a seal part and folding a partition part. Can be stored in a storage location.

  According to the invention described in claim 4, since the water stop device for the suction pipe is installed so as to come into contact with the surface on the water discharge channel side of the work scaffold, when water flows in (reverse flow) from the water discharge channel side (downstream side). The water pressure applied to the suction pipe water stop device is transmitted to the work scaffold, and the work pipe scaffold supports the suction pipe water stop device (supporting the holding of the partition portion by the seal portion). For this reason, the water stop by the water stop apparatus for suction pipes is maintained favorably.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

  FIG. 1 is a front view (a) and a plan view (b) showing a water stop device 1 for a suction pipe according to an embodiment of the present invention. The suction pipe water stop device 1 is mainly composed of an annular tube 2 (seal part) and a partition plate 3 (partition part).

  Like the tube (inner tube) of an automobile tire, the annular tube 2 is made of rubber and formed in an annular shape, and a valve 21 for flowing in and out of air is attached to the annular tube 2. Then, when air (gas) is introduced from the valve 21, the tube (tube) having a circular cross section is formed into a donut shape, and when air is discharged from the valve 21, the tube 21 is compressed and flattened. Further, the outer diameter of the annular tube 2 in the swollen state is set larger than the inner diameter of the suction pipe D described later. That is, as will be described later, when the annular tube 2 swells at a constant high pressure, the annular tube 2 comes into contact with the entire inner peripheral surface of the suction pipe D and the space between the partition plate 3 and the inner peripheral surface of the suction pipe D is The annular tube 2 is swelled so that the annular tube 2 is pressed against the inner peripheral surface of the suction pipe D and the partition plate 3 is held in the suction pipe D. The diameter is set.

  The partition plate 3 includes a first partition plate 31 and a second partition plate 32 that are plate-shaped and made of resin. The first partition plate 31 and the second partition plate 32 are both semicircular, and their straight portions are connected to each other by a hinge 33 (hinge). In addition, a sealing material 34 (packing) is bonded to the linear edge of the first partition plate 31, and the first partition plate 31 and the second partition plate 32 are expanded (deployed) to form a flat surface. The partition plate 3 is formed, and the space between the first partition plate 31 and the second partition plate 32 is hermetically sealed (sealed tightly) by the sealing material 34. The outer diameter of the partition plate 3 is set to be smaller than the outer diameter when the annular tube 2 is expanded, and larger than the inner diameter when the annular tube 2 is expanded. And the lower surface 3a (surface on the opposite side to the hinge 33) of the partition plate 3 and the upper surface 2a of the annular tube 2 are joined so as to block the ring of the annular tube 2, and the water stop device 1 for the suction pipe is configured. Yes.

  When air is introduced into the annular tube 2 of the suction pipe water stop device 1, the annular tube 2 swells in a donut shape as described above, and the first partition plate 31 and the second partition plate 32 are associated with the swelling. Is opened so that a circular partition plate 3 is formed. When the suction pipe water stop device 1 is installed in the suction pipe D as described later, the partition pipe 3 partitions the suction pipe D into the Francis turbine T side and the discharge channel R side. On the other hand, when air is extracted from the annular tube 2, the annular tube 2 is contracted and flattened as described above, and the first partition plate 31 and the second partition plate 32 can be folded via the hinge 33.

  Next, the installation method of the suction pipe water stop device 1 having such a configuration will be described with reference to FIGS. In the figure, T is a Francis turbine (turbine), and a generator (not shown) is connected to the output shaft T1 of the Francis turbine T. The intake pipe S is connected to the casing T2 of the Francis turbine T, and the suction pipe D is connected to the suction outlet T3 of the Francis turbine T. Then, water from a water intake (not shown) is supplied to the Francis turbine T via the intake pipe S, the Francis turbine T rotates, and the suction water from the Francis turbine T is discharged into the discharge channel R via the suction pipe D. To be guided to.

  A manhole D1 for an operator to enter and exit is provided on the upper end side (the Francis turbine T side) of the suction pipe D, and two working scaffolds D2 are provided in the suction pipe D located below the manhole D1. is set up. That is, two pairs of concave scaffolding support portions D3 are formed on the inner wall of the suction pipe D so as to face each other, and the scaffold support portions D3 are installed in a state where both ends of the work scaffolding D2 are supported. In addition, the suction pipe D of such a structure is a structure equivalent to the existing existing suction pipe, and in order to install the water stop apparatus 1 for suction pipes, it is not what was processed and installed separately.

  In order to install the water stop device 1 for the suction pipe in the suction pipe D, first, the first partition plate 31 and the second partition plate 32 are placed in a state where the air is removed from the annular tube 2 as described above. Folding and carrying out the suction pipe water stop device 1 into the suction pipe D from the manhole D1. Next, the water stop device 1 for the suction pipe is positioned below the work platform D2 (on the water discharge path R side), the first partition plate 31 and the second partition plate 32 are spread, and the partition plate 3 is attached to the work platform D2. It is made to contact the lower surface (surface on the side of the water discharge channel R). At this time, the worker can work on the work scaffold D2. In this state, air (compressed air) is introduced from the valve 21 into the annular tube 2 to inflate the annular tube 2 and make the inside of the annular tube 2 have a constant high pressure. That is, the space between the partition plate 3 and the inner peripheral surface of the suction pipe D is tightly sealed by the annular tube 2 so that water from the discharge channel R side (downstream side) does not flow (backflow) into the Francis turbine T side, and The inside of the annular tube 2 is pressurized to such a high pressure that the annular tube 2 presses the inner peripheral surface of the suction pipe D and the partition plate 3 is firmly held in the suction pipe D. It should be noted that the material, thickness, and the like of the material (rubber) of the annular tube 2 are selected and set so as to withstand such a high pressure. As a result, the space between the partition plate 3 and the inner peripheral surface of the suction pipe D is sealed by the annular tube 2, and the lower surface of the work scaffold D2 is brought into contact with the partition plate 3 held in the suction pipe D. In this way, the suction pipe water stop device 1 is installed.

  In the state where the suction pipe water stop device 1 is installed in this manner, the inside of the suction pipe D is partitioned by the partition plate 3, and the space between the partition plate 3 and the inner peripheral surface of the suction pipe D is sealed by the annular tube 2. Therefore, the water from the discharge channel R side is stopped (prevented) from flowing into the Francis turbine T side. For this reason, the worker can inspect and maintain the inside of the Francis turbine T and the like without being concerned about the inflow of water in a state of being located closer to the Francis turbine T than the suction pipe water stop device 1. On the other hand, when the inspection, maintenance, etc. of the Francis turbine T are completed, the first partition plate 31 and the second partition plate 32 are folded in a state where the air is extracted from the annular tube 2 and the annular tube 2 is contracted and flattened. . And what is necessary is just to carry out the water stop apparatus 1 for suction pipes out of the suction pipe D from the manhole D1.

  According to the water shutoff device 1 for the suction pipe having such a configuration, it has a simple configuration (structure) mainly composed of the annular tube 2 and the partition plate 3. By putting air into the annular tube 2, the annular tube 2 and the partition are separated. The suction pipe D is stopped by the plate 3. Moreover, since the partition plate 3 is held in the suction pipe D simply by introducing air into the annular tube 2, that is, the suction pipe water stop device 1 is installed in the suction pipe D. 1 is very easy to install. Moreover, since the annular tube 2 expands when air is introduced and the space between the partition plate 3 and the inner peripheral surface of the suction pipe D is sealed, that is, sealed by the air pressure (hydrostatic pressure), the partition plate 3 and The space between the suction pipe D and the inner peripheral surface can be uniformly and stably sealed.

  Furthermore, since the partition plate 3 is plate-shaped and is disposed on the upper surface 2a of the annular tube 2 so as to close the ring of the annular tube 2, the operator can use the partition plate 3 as a scaffold plate, Inspection, maintenance, etc. of the interior of the Francis turbine T can be performed easily and safely. On the other hand, when the water stop device 1 for the suction pipe is not used, the first partition plate 31 and the second partition plate 32 can be folded by removing the air from the annular tube 2. For this reason, the water stop apparatus 1 for suction pipes can be conveyed (carrying in / out) in a compact state or stored in a storage location.

  Moreover, in this embodiment, since the suction pipe water stop device 1 is installed so as to contact the lower surface of the work scaffold D2 as described above, when water flows from the discharge channel R side, the suction pipe stop is stopped. The water pressure applied to the water device 1 is transmitted to the work scaffold D2, and the suction pipe water stop device 1 is firmly supported by the work scaffold D2. That is, the holding of the partition plate 3 by the annular tube 2 is firmly supported. For this reason, the water stop by the water stop apparatus 1 for suction pipes is maintained favorably. Furthermore, the suction pipe water-stop device 1 can be installed and removed only by entering and exiting the annular tube 2, and the suction pipe water-stop device 1 can be used repeatedly.

  Although the embodiment of the present invention has been described above, the specific configuration is not limited to the present embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included in the present invention. It is. For example, in this embodiment, the partition plate 3 is divided into the two partition plates 31 and 32. However, the suction pipe water stop device may be folded more compactly by dividing the partition plate 3 into more partition plates. Further, the partition plate 3 may be constituted by a single plate without being divided so as to enhance the strength and sealing performance of the partition plate 3. Furthermore, the two partition plates 31 and 32 may be fixed with a connection plate or the like to increase the strength of the partition plate 3, and the two partition plates 31 and 32 are expanded in order to improve installation workability and the like. A hook or a handle that is temporarily fixed in a state may be provided. Furthermore, the partition plate 3 may be fixed to the work scaffold D2 when the suction pipe water stop device 1 is installed.

  In this embodiment, the seal portion is an annular tube 2, but as shown in FIG. 5, the seal portion 41 is formed in a disc shape, and a plate-like partition portion 42 is joined to the upper surface of the seal portion 41. The suction pipe water stop device 4 may be configured. Furthermore, a water stop device for a suction pipe in which a seal portion and a partition portion are integrally formed may be used. That is, the suction pipe water-stop device is composed of an inflatable body such as a balloon (corresponding to the seal part 41 in FIG. 5), the central part is a partition part, and the outer peripheral part (the inner peripheral surface side of the suction pipe D) is sealed. You may make it be a part.

It is the front view (a) and top view (b) which show the water stop apparatus for suction pipes concerning embodiment of this invention. It is a schematic sectional drawing which shows the positional relationship of the water stop apparatus for suction pipes concerning embodiment of this invention, a Francis turbine, etc. It is sectional drawing which shows the state which installed the water stop apparatus for the suction pipe concerning embodiment of this invention in the suction pipe. It is AA sectional drawing of FIG. It is the front view (a) and top view (b) which show the 2nd water stop apparatus for suction pipes concerning embodiment of this invention.

Explanation of symbols

1 Water stop device for suction pipe 2 Annular tube (seal part)
21 Valve 3 Partition plate (partition)
31 1st partition plate 32 2nd partition plate 33 Hinge 34 Seal material T Francis turbine (turbine)
S intake pipe D suction pipe D1 manhole D2 work scaffold D3 scaffold support R discharge channel

Claims (4)

A water stop device for a suction pipe installed inside the suction pipe for guiding the suction water from the water wheel to the water discharge channel, and for stopping the suction pipe;
A partition for partitioning the suction pipe into the water wheel side and the water discharge side;
A seal portion that swells when gas is introduced and seals between the partition portion and the inner peripheral surface of the suction pipe, presses the inner peripheral surface of the suction pipe, and holds the partition portion in the suction pipe;
A water stop device for a suction pipe, comprising: The seal portion is formed in an annular shape, and a plate-like partition portion is disposed so as to close the inside of the seal portion.
The water stop device for a suction pipe according to claim 1. The partition is formed to be foldable,
The water stop device for a suction pipe according to claim 2. An installation method for installing the water stop device for a suction pipe according to any one of claims 1 to 3, inside a suction pipe for guiding suction water from a water wheel to a water discharge channel,
Positioning the partition portion so as to contact the surface of the water discharge channel side of the work scaffold installed in the suction pipe, and put gas into the seal portion,
The installation method of the water stop apparatus for suction pipes characterized by the above-mentioned.

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