JP2014029194A - Method of removing valve cover of gate valve and gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of removing a valve cover of a gate valve which facilitates removing operation of the valve cover provided with a valve body and a valve rod in non-cutoff water state with high efficiency while reducing construction cost.SOLUTION: A method of removing a valve cover 4 of a gate valve includes: a process of attaching an annular attachment base material to a valve box 2 in a water-tight state while allowing insertion and removal operation of a lock member; a process of maintaining water-tight state between the valve cover 4 and the valve box 2 by pushing the valve cover 4 against the valve box 2 by means of a pushing means provided on the attachment base material; a process of releasing fastening connection between a connection outer fitting part 2A of the valve box 2 and a connection inner fitting part 4A of the valve cover 4; a process of attaching a working housing H provided with a working opening and closing valve V2 and an elevation conveying means D connected to the valve cover 4 to the attachment base material in water-tight state; and a process of releasing the pushing fastening of the pushing means, taking out the valve cover 4 into the working housing H with the elevation conveying means D and performing valve-closing operation of an operating opening and closing valve V2.

Description

  The present invention is the gate valve connected to the fluid piping system, when the valve body having a short life compared to the valve box reaches the set durability years, or when the valve body malfunctions, The present invention relates to a valve cover removal method for a gate valve that removes a valve cover including a valve body and a valve stem from a valve box in an indefinite water state, and an improved technique for a gate valve used therefor.

  In general, as a gate valve connected to a fluid piping system, a flange formed on a valve body mounting portion of a valve box and a flange formed on a valve lid are fastened and fixed in a watertight state with bolts and nuts. A gate valve is used.

As a valve lid removal method using such a general gate valve,
The lower housing of the divided structure that surrounds substantially the entire gate valve in a state including a part of both the fluid pipes in both the upstream and downstream fluid pipes connected to the valve box of the gate valve in a watertight state. Installation process,
A step of maintaining the watertight state between both flanges by sandwiching and fixing the flange of the valve box and the flange of the valve lid from the outside by a flange holding device provided in the lower housing;
Removing the bolts and nuts that fasten and fix the flange of the valve box and the flange of the valve lid;
A step of connecting a lower end portion of a lower divided lifting shaft portion among a plurality of divided lifting shaft portions constituting a lifting shaft of a lifting and lowering conveying device equipped in an upper housing to an upper end portion of a valve stem of a gate valve;
Fixing the lower flange of the work on / off valve to the flange of the upper opening of the lower housing in a watertight state with bolts and nuts;
The upper part of the lifting / lowering shaft part of the lifting / lowering conveying device provided in the upper housing is connected to the lower part of the lifting / lowering shaft part connected to the valve rod of the gate valve and the upper flange of the work on / off valve. A process of fixing and connecting the lower flange of the upper housing in a watertight state with bolts and nuts,
After releasing the pinching between the flange of the valve box and the flange of the valve lid by the flange holding device, the lifting shaft of the lifting and lowering conveying device is lifted so that the valve lid with the valve body and the valve stem is placed in the storage space of the upper housing Taking out the inside and closing the work on-off valve,
Removing the valve lid taken out in the storage space of the upper housing;
A valve lid removal method having the above steps has been proposed (see, for example, Patent Document 1).

JP2007-177945

  The conventional method for removing the valve lid of the gate valve requires a lower housing having a large divided structure for enclosing substantially the entire gate valve in a state including a part of both fluid pipes. Since the excavation volume also becomes large, the construction becomes large and there is a disadvantage that the construction cost increases.

  Further, the flange of the valve box and the flange of the valve lid are fastened and fixed by a large number of bolts and nuts, and it is necessary to perform the removal work of the large numbers of bolts and nuts in a limited space in the lower housing. Therefore, there is an inconvenience that a great deal of labor is required to release the connection between the flange of the valve box and the flange of the valve lid.

  The present invention has been made in view of the above-described actual situation, and the main problem is that the removal of the valve lid provided with the valve body and the valve stem in an indefinite water state is performed while reducing the construction cost. The object is to provide a valve cover removal method for a gate valve that can be efficiently and easily performed, and a gate valve that contributes to efficiency and ease of the removal work.

A first characteristic configuration according to the present invention includes a valve box connected to a fluid piping system, a valve lid fitted and connected to the valve box, and a valve rod penetrating the valve lid. A valve body that is detachably mounted from the valve body mounting port, a valve box side connection fitting part and a valve lid side connection fitting part that constitute a fitting connection part between the valve box and the valve lid. A gate valve having a locking member that can be freely inserted and removed from the outside, and a locking means that fixes and connects the valve box and the valve lid in a watertight state in an engaged state in which the locking member is inserted, A valve cover removal method for a gate valve that removes the valve cover provided with the valve body and the valve stem from the valve box in an indefinite water state,
Attaching the annular attachment base material to the valve box in a watertight state in a state allowing the lock member to be inserted and removed;
By pressing the valve lid against the valve box by the pressing means provided on the mounting base material, the space between the coupling inner fitting portion of the valve lid and the coupling outer fitting portion of the valve box is maintained in a watertight state. Process,
Extracting the locking member of the locking means, and releasing the fixed connection between the connection fitting part of the valve box and the connection fitting part of the valve lid;
Attaching a work housing provided with a lifting and lowering conveying means connected to the work opening and closing valve and the valve lid to the attachment base material in a watertight state;
Releasing the pressing and fixing of the presser means, and taking out the valve lid into the storage space of the work housing by the lifting and lowering means, and then closing the work on-off valve; and
Removing the valve lid taken out in the storage space of the working housing;
It is in the point equipped with.

  According to the above configuration, the gate valve connected to the fluid piping system has a lock member that can be inserted and removed from the outside with respect to the coupling outer fitting portion on the valve box side and the coupling inner fitting portion on the valve lid side. And, in the engaged state in which the lock member is inserted, there is provided a locking means for fixing and connecting the valve box and the valve lid in a watertight state, so even when releasing the fixed connection between the valve box and the valve lid, It is only necessary to pull out the lock member, and the valve cover can be fixed and released more efficiently and easily than the conventional gate valve, in which the valve box and valve cover are fastened and fixed with many bolts and nuts. be able to.

  In addition, when removing a valve cover that has reached a set endurance life or a valve element that has malfunctioned, first, the valve box is annular in a state that allows the lock member to be inserted and removed. A mounting housing is attached in a watertight state, and a work housing provided with a lifting and lowering conveying means connected to the opening / closing valve and the valve lid is attached to the mounting base in a watertight state. Compared to the conventional method using a divided lower housing that surrounds substantially the whole of the gate valve in a state where the gate valve is included, the housing required for the lower side of the gate valve and part of both fluid pipes should be reduced. In addition, the excavation volume of the work pit can be reduced accordingly.

  Further, even when the annular mounting base material is attached to the valve box, the lock member can be inserted and removed, and when the lock member is inserted and removed, the valve lid is provided by a pressing means provided on the mounting base material. Is pressed against the valve box, and the space between the coupling inner fitting part of the valve lid and the coupling outer fitting part of the valve box is maintained in a watertight state. It is possible to eliminate or reduce the effect of the insertion / removal operation resistance, and it is possible to easily perform the insertion / removal operation of the lock member with a light force.

  Further, when releasing the pressing and fixing of the valve lid by the pressing means, the hydraulic pressure acting on the valve lid side can be received and supported by the lifting / lowering conveying means on the work housing side connected to the valve lid. The pressing and fixing operation of the pressing means can be easily performed with a light force.

  Therefore, the removal operation of the valve lid provided with the valve body and the valve stem in an indefinite water state can be efficiently and easily performed while reducing the construction cost.

  A second characteristic configuration according to the present invention is that the pressing means is configured to press the valve lid against the valve box via a pressing member that is detachably attached to the valve lid.

  According to the above configuration, the valve lid can be reliably and easily pressed and fixed to the valve box via the presser member mounted on the valve lid without being obstructed by the constituent members present on the upper surface of the valve lid. Therefore, the presser means can be simplified.

  A third characteristic configuration according to the present invention lies in that the mounting base material is clamped and fixed to a protruding portion formed in a lower portion of the valve box than the insertion / extraction operation position of the locking member.

  According to the above configuration, the load of the work housing provided with the work on-off valve and the lifting and lowering conveying means and the load of the valve lid taken out by the lifting and lowering conveying means act on the mounting base material clamped and fixed to the protrusion of the valve box. However, this large load can be reliably received and supported by the projection of the sturdy valve box.

  In addition, the protrusion of the valve box is formed so as to protrude below the position of the lock member insertion / removal operation, and the mounting base material clamped and fixed to the protrusion allows the lock member to be inserted / removed in the first place. Since it is configured, the lock member can be easily inserted and removed.

  Therefore, a load supporting device for supporting the mounting base material so that it does not slide along the outer surface of the valve box as in the case where the mounting base material is clamped and fixed to the smooth outer surface of the valve box. There is no need to provide it separately, and it is possible to promote the reduction of the construction cost while maintaining the ease of inserting and removing the lock member, and it is possible to facilitate the assembly work at the construction site and increase the efficiency.

  According to a fourth characteristic configuration of the present invention, the mounting base is mounted in a watertight state at a position below the insertion / extraction operation position of the lock member in the valve box in a watertight state, and the mounting base is in a watertight state. And an annular mounting frame that surrounds at least a part of the valve lid, and the pressing step by the pressing means corresponds to an internal space of the annular mounting frame in the mounting base portion before the mounting of the annular mounting frame. A step of pressing and fixing the valve lid to the valve box side with a first pressing jig provided in the region, and a second pressing jig that can be operated from the outside provided on the annular mounting frame after the annular mounting frame is mounted And the step of pressing and fixing the valve lid to the valve box side.

  According to the above configuration, the mounting base is composed of a mounting base portion and an annular mounting frame, and the pressing means is also composed of a first pressing jig and a second pressing jig, and the mounting base portion is attached to the valve box. In the state where only the base member is attached, the attachment base portion is located below the lock member insertion / removal operation position, so that the first presser foot provided on the attachment base portion does not interfere with the lock member insertion / removal operation. The valve lid can be pressed and fixed to the valve box side with a tool.

  Moreover, since the first pressing jig is disposed in the area corresponding to the inner space of the annular mounting frame, even when the annular mounting frame that surrounds at least a part of the valve lid is mounted on the mounting base portion, The annular mounting frame can be securely and easily mounted without being obstructed.

  Further, after the mounting of the annular mounting frame, the valve lid is pressed and fixed to the valve box side by a second presser jig that can be operated from the outside provided on the annular mounting frame. The pressing and fixing release operation of the holding jig can be easily performed, and the pressing and releasing operation of the second holding jig can be easily performed from the outside of the annular mounting frame when the work housing is attached to the mounting base. be able to.

According to a fifth feature of the present invention, after the step of removing the valve lid,
Connecting another valve lid equipped with at least a new valve body to the lifting and lowering conveying means provided in the work housing;
Opening the work on / off valve, another valve lid in the storage space of the work housing is lowered to the valve box side by the lifting and lowering conveying means, and a connection fitting portion of the other valve lid is installed. A step of fitting and connecting to a coupling outer fitting portion of the valve box;
A step of fixing and coupling a coupling inner fitting portion of another valve lid that is fitted and connected to a coupling outer fitting portion of the valve box with a locking member of the locking means;
Is in the point that is provided.

  According to the above-described configuration, the coupling inner fitting portion of at least another valve lid equipped with a new valve element is fitted and connected to the coupling outer fitting portion of the valve box, and another operation is performed by inserting the locking member of the locking means. Construction of a gate valve equipped with a valve body that has reached the set endurance life or a valve body that has malfunctioned by fixedly connecting the inner fitting part of the valve lid and the outer fitting part of the valve box. It is possible to rehabilitate efficiently while reducing costs.

  In addition, after the other valve lid connected to the lifting / lowering conveying means of the work housing is operated to be lowered and the connection inner fitting portion thereof is fitted and connected to the connection outer fitting portion of the valve box, the first feature described above. The steps of the configuration may be executed in the reverse order, and the locking member of the locking means may be inserted and operated across the coupling inner fitting portion of another valve lid that is fitted and connected and the coupling outer fitting portion of the valve box. However, it is possible to press and fix another valve lid to the valve box in a watertight state by the lifting and lowering conveying means, and a work window or work arm in which a lock member can be inserted and operated from the outside of the mounting base Etc., when the other valve lid is pressed and fixed to the valve box in a watertight state by the lifting and lowering conveying means without performing the steps in the first characteristic configuration in the reverse order, Lock the connecting inner fitting part of the valve lid and the connecting outer fitting part of the valve box. It can be fixedly connected with member.

According to a sixth feature of the present invention, after the step of removing the valve lid,
Connecting the lid for closing the valve body mounting port of the valve box in a watertight state to the lifting and lowering conveying means provided in the work housing;
The opening / closing valve for the operation is opened, and the lid in the storage space of the working housing is lowered to the valve box side by the lifting and lowering conveying means, and the connection fitting portion of the lid is connected to the valve box A step of fitting and connecting to the outer fitting portion;
A step of fixing and connecting the coupling inner fitting portion of the lid body fitted and connected and the coupling outer fitting portion of the valve box with the locking member of the locking means;
Is in the point that is provided.

  According to the above configuration, the connecting inner fitting portion of the lid that closes the valve body mounting port portion of the valve box in a watertight state is fitted and connected to the connecting outer fitting portion of the valve box, and the lock member insertion operation of the locking means By fixing and connecting the connecting inner fitting part of the lid and the connecting outer fitting part of the valve box, the valve body mounting port part of the valve box is efficiently and reliably closed, and only the valve box having excellent durability is sealed. It can continue to be used as part of the pipeline.

  In addition, after the connecting internal fitting portion of the lid body connected to the lifting and lowering conveying means of the work housing is lowered and fitted and connected to the connecting external fitting portion of the valve box, the process according to the first characteristic configuration described above is performed. In the reverse order, the locking member of the locking means may be inserted and operated across the coupling inner fitting part of the lid body fitted and connected and the coupling outer fitting part of the valve box. When the lid can be pressed and fixed to the valve box in a watertight state, and the mounting base is equipped with a work window or work arm that can be operated by inserting a lock member from the outside. When the lid body is pressed and fixed to the valve box in a watertight state by the lifting and lowering conveying means without performing the steps in the first characteristic configuration in the reverse order, the coupling of the lid body that is fitted and connected The inner fitting part and the connection outer fitting part of the valve box are fixedly connected with a lock member. Can.

According to a seventh feature of the present invention, after the valve lid removal step,
Connecting the assembly of the repair valve and the valve mounting member provided with the coupling inner fitting portion that can be fitted and connected to the coupling outer fitting portion of the valve box to the lifting and lowering conveying means provided in the work housing;
Opening the work on / off valve, the assembly in the storage space of the work housing is lowered to the valve box side by the lifting and lowering conveying means, and the connection fitting part of the valve mounting member is connected to the valve box. A step of fitting and connecting to the outer fitting portion;
A step of fixing and coupling the coupling inner fitting portion of the valve mounting member fitted and connected to the coupling outer fitting portion of the valve box with the locking member of the locking means;
Is in the point that is provided.

  According to the above configuration, among the assembly of the repair valve and the valve mounting member provided with the coupling inner fitting portion, the coupling inner fitting portion of the valve mounting member is fitted and connected to the coupling outer fitting portion of the valve box, As a repair valve having a different function by using the valve box of the gate valve as it is by fixing and connecting the connection fitting part of the valve mounting member and the connection fitting part of the valve box by inserting the lock member of the locking means. It can be regenerated with efficiency and low construction costs.

  In addition, the assembly of the repair valve and the valve mounting member connected to the lifting and lowering conveying means of the work housing is lowered, and the connecting inner fitting portion of the valve mounting member is fitted and connected to the connecting outer fitting portion of the valve box. Thereafter, the steps of the first characteristic configuration described above are executed in the reverse order, and the locking means is locked across the coupling inner fitting portion of the valve mounting member that is fitted and connected and the coupling outer fitting portion of the valve box. The member may be inserted and operated, but the valve mounting member can be pressed and fixed to the valve box in a watertight state by the lifting and lowering conveying means, and the locking member is inserted and operated from the outside of the mounting base. If the work window and work arm that can be operated are equipped, the valve mounting member is made watertight in the valve box by the lifting and lowering conveying means without performing the steps in the first characteristic configuration in the reverse order. When it is pressed and fixed, it is not mated and connected. It can be fixed connecting the connecting-fitting portion of the coupling in the fitting portion and the valve casing of the valve mounting member in the locking member.

According to an eighth feature of the present invention, there is provided a valve box connected to a fluid piping system, a valve lid fitted and connected to the valve box, and a valve rod penetrating the valve lid. A gate valve provided with a valve body that is detachably mounted from the valve body mounting port,
The fitting connection part between the valve box and the valve lid is detachable from the outside with respect to the connection outer fitting part on the valve box side and the connection inner fitting part on the valve lid side constituting the fitting connection part. In the engaged state where the lock member is inserted and in which the lock member is inserted, there is provided a lock means for fixing and connecting the valve box and the valve lid in a watertight state. A projecting portion capable of attaching an annular attachment base material is integrally formed at a portion biased downward from the position.

  According to the above configuration, the gate valve connected to the fluid piping system has the lock member that can be inserted and removed from the outside with respect to the coupling outer fitting portion on the valve box side and the coupling inner fitting portion on the valve lid side. And, in the engaged state in which the lock member is inserted, there is provided a locking means for fixing and connecting the valve box and the valve lid in a watertight state, so even when releasing the fixed connection between the valve box and the valve lid, It is only necessary to pull out the lock member, and the valve cover can be fixed and released more efficiently and easily than the conventional gate valve, in which the valve box and valve cover are fastened and fixed with many bolts and nuts. be able to.

  In addition, since a protruding portion to which an annular mounting base material can be attached is integrally formed at a portion of the valve box that is biased downward from the insertion / extraction operation position of the lock member, for example, a valve body and a valve rod are provided. When removing the valve cover from the valve box in an unrestricted state, the mounting base that is clamped and fixed to the protruding part of the valve box is loaded with the load of the work housing and the lifting and lowering conveying means provided with the working on-off valve and the lifting and lowering conveying means. Even if the load of the valve lid to be taken out acts, this large load can be reliably received and supported by the projection of the sturdy valve box.

  In addition, since the protruding portion of the valve box protrudes from the position below the lock member insertion / removal operation position, the lock member can be easily inserted / removed even if the attachment base material is clamped and fixed to the protrusion. be able to.

  Therefore, a load supporting device for supporting the mounting base material so that it does not slide along the outer surface of the valve box as in the case where the mounting base material is clamped and fixed to the smooth outer surface of the valve box. There is no need to provide it separately, and it is possible to promote the reduction of the construction cost while maintaining the ease of inserting and removing the lock member, and it is possible to facilitate the assembly work at the construction site and increase the efficiency.

The perspective view of the gate valve of the water piping system which shows 1st Embodiment of this invention. Partial cutaway front view of gate valve Partial cutaway plan view of gate valve at line III-III in Fig. 2 Perspective view when mounting base part of mounting base is assembled A perspective view when the lower base member of the mounting base portion is assembled. A perspective view when the upper base member of the mounting base portion is assembled. Perspective view when assembling the presser member Partially cutaway front view of the mounting base of the mounting base Partially cutaway front view when the presser member is assembled Partially cutaway front view when the lock member is pulled out (a) and partially cutaway side view perpendicular to it (b) Perspective view when assembling the annular mounting frame of the mounting base Partially cutaway front view of the mounting base ring mounting frame Partially cutaway front view when the work housing is assembled Partially cutaway front view when the valve lid is taken out into the storage space of the work housing Partially cutaway front view when the work housing is lifted separately from the work on / off valve Partially cutaway front view showing a second embodiment of the present invention Partially cutaway front view showing a third embodiment of the present invention

[First Embodiment]
1 to 3 show a gate valve V1 that is flange-joined in the middle of a water pipe 1 of a water pipe system that is an example of a fluid pipe constituting the fluid piping system.
The gate valve V1 is formed in a cast iron valve box 2 that is connected to the upstream and downstream water pipes 1 and has a substantially inverted T shape when viewed from the side, and an opening is formed at the upper end of the valve box 2. From the valve body mounting port portion 3 of the valve box 2 via the valve lid 4 made of cast iron fitted and connected to the valve body mounting port portion 3 from above and the valve rod 5 penetrating the valve lid 4. A connecting outer fitting portion 2A on the valve box 2 side and a valve lid 4 side constituting a fitting connecting portion A between the valve body 6 provided with a rubber lining which is detachably attached and the valve box 2 and the valve lid 4 are provided. In the engaged state in which the lock member 7A is inserted and removed from the laterally outer side with respect to the connecting inner fitting portion 4A and the lock member 7A is inserted, the valve box 2 and the valve lid 4 are in a watertight state. Locking means 7 for fixed connection is provided.

  The valve box 2 has a circular cross-sectional shape with a pair of connection flanges 2B fixedly connected to the connection flanges 1A of both water pipes 1 by bolts 10A and nuts 10B as an example of the first fastening means 10 in a watertight state. Horizontal valve box portion 2C and a vertical valve box having a substantially rectangular cross-sectional shape (rounded rectangular shape) formed integrally in a direction orthogonal to the central portion of the horizontal valve box portion 2C in the flow axis direction Part 2D.

  On the inner surface of the valve box 2, the valve body 6 screwed into the threaded shaft portion of the valve stem 5 is in a non-rotatable state at a flow path opening position (valve opening position) and a flow path blocking position (valve closing position). The rubber lining portion 6a of the valve body 6 moved to the flow passage blocking position by the rotation operation of the sliding guide portion 2e for sliding guide and the rotation operation portion 5a formed on the upper end portion of the valve stem 5 with a square axis. And a valve seat in contact with the valve.

  In addition, an annular connecting outer fitting portion 2A having an upper end side peripheral wall portion of the vertically oriented valve box portion 2D and having a substantially rectangular shape (corner round rectangular shape) in cross-sectional shape forming the valve body mounting port portion 3 is integrally formed. ing.

  The connecting outer fitting portion 2A has a length in the valve body mounting direction corresponding to at least the fitting depth of the valve lid 4 with the connecting inner fitting portion 4A, and from the inner peripheral surface of the vertically oriented valve box portion 2D. And the plate thickness is thicker than the vertical valve box portion 2D, and the boundary between the inner peripheral surface 2a of the connecting outer fitting portion 2A and the inner peripheral surface 2d of the vertical valve case portion 2D. A step portion 2b for forming a seal portion is formed in a portion corresponding to the back side which is the side.

  At the lower end portion of the outer peripheral surface of the connecting outer fitting portion 2A, which is biased downward from the insertion / removal operation position of the lock member 7A, an annular protrusion 9 capable of attaching an annular attachment base B, which will be described later, in a clamped state, It is integrally formed in a posture that is parallel or substantially parallel to the upper end surface 2g of the connecting outer fitting portion 2A, and the thickness of the projection 9 is the same or substantially the same as the thickness of the connecting outer fitting portion 2A. It is configured.

  The valve lid 4 has a substantially similar plate-like valve lid body 4B that can be brought into contact with the upper end surface 2g of the coupling outer fitting portion 2A of the valve box 2, and the connection of the valve box 2 from the inner surface of the valve lid body 4B. A cylindrical connecting inner fitting portion 2A projecting with a fitting size slightly smaller than the inner surface size of the outer fitting portion 2A, and a shaft support portion 4C for penetrating and supporting the valve rod 5 in a watertight state so as to be freely rotatable. A pair of suspension hooks 4D for moving up and down the valve lid 4 including the valve body 6 and the valve stem 5 around the shaft support portion 4C on the outer surface of the valve lid body 4B. The arc-shaped mounting bracket 4E is integrally formed.

  The tip side portion of the outer peripheral surface of the connecting inner fitting portion 4A of the valve lid 4 and the rear side step portion 2b of the inner peripheral surface 2a of the connecting outer fitting portion 2A of the valve box 2 corresponding to this in the valve body mounting direction include a valve Tapered surfaces 4a, 2f having the same or substantially the same gradient are formed on the inner flow path side of the laterally facing valve box portion 2C of the box 2 and the outer peripheral surface of the coupling inner fitting portion 4A of the valve lid 4 is formed. When the coupling inner fitting portion 4A of the valve lid 4 is fitted to the predetermined fitting mounting position with respect to the coupling outer fitting portion 2A of the valve box 2, both tapered surfaces are formed in the seal mounting groove 4b formed in A gasket 8 that is an example of an annular sealing material that is compressed between both tapered surfaces 4a and 2f is mounted so that the space between 4a and 2f is watertight.

  The locking means 7 is formed through each of a plate-like locking member 7A formed in a substantially U shape in plan view and a wall portion facing each other in the long side direction of the connecting external fitting portion 2A of the valve box 2. Outer engagement holes (outer engaged portions) 7B and inner engagement recesses 7C formed on the outer surfaces of the wall portions facing each other in the long side direction of the coupling inner fitting portion 4A of the valve lid 4 ( Inner engaged portion).

  Each outer engagement hole 7B in the connection outer fitting portion 2A of the valve box 2 is configured to have a hole size in which the lock member 7A is detachably inserted from the lateral outer side in the long side direction, and the valve lid 4 is connected. Each inner engagement recess 7 </ b> C in the inner fitting portion 4 </ b> A is configured to have a hole size with which the distal end side of the lock member 7 </ b> A engaged with each outer engagement hole 7 </ b> B of the connection outer fitting portion 2 </ b> A of the valve box 2 is engaged. Yes.

  The lock member 7A includes a center lock plate portion 7Aa along the short side direction of the connecting outer fitting portion 2A and the connecting inner fitting portion 4A, and the connecting outer fitting portion 2A and the connecting inner fitting portion 4A from both ends of the center lock plate portion 7Aa. The side lock plate portion 7Ab is integrally extended along the long side direction toward the central position side in the long side direction.

  The outer surface of the center lock plate portion 7Aa of the lock member 7A includes an outer engagement hole 7B in the coupling outer fitting portion 2A of the valve box 2 and an inner engagement concave portion 7C in the coupling inner fitting portion 4A of the valve lid 4. When in the locked state, the outer surface of the coupling outer fitting portion 2A of the valve box 2 is flush with or substantially flush with the outer surface.

  Therefore, the outer surface of the lock member 7A that appears outside from the outer engagement hole 7B of the coupling outer fitting portion 2A of the valve box 2 includes a portion along the short side direction and a portion along the long side direction of the coupling outer fitting portion 2A. Since it is formed in a substantially flat U-shape or U-shape provided, it becomes easier to grip the outer surface of the lock member 7A that appears outside from the outer engagement hole 7B of the connecting outer fitting portion 2A. The extraction operation of 7A can be performed efficiently and smoothly.

  The outer engagement hole 7B communicates with a center through hole portion 7Ba through which the center lock plate portion 7Aa of the lock member 7A passes and a side engagement groove portion 7Bb with which both side lock plate portions 7Ab of the lock member 7A are engaged. Configured.

  The inner engagement recess 7C includes a center engagement groove 7Ca that engages with the center lock plate 7Aa of the lock member 7A and a side engagement groove 7Cb that engages both side lock plates 7Ab of the lock member 7A. It is configured to communicate in a letter shape.

  As shown in FIG. 2, the lock member 7 </ b> A is engaged over the outer engagement hole 7 </ b> B in the connection outer fitting portion 2 </ b> A of the valve box 2 and the inner engagement recess 7 </ b> C in the connection inner fitting portion 4 </ b> A of the valve lid 4. In the locked state, the gasket 8 is compressed to a watertight state between the tapered surface 4a of the coupling inner fitting portion 4A of the valve lid 4 and the tapered surface 2f of the coupling outer fitting portion 2A of the valve box 2, The elastic restoring force of the gasket 8 acts as a pull-out resistance (insertion resistance) of the lock member 7A, and the lock member 7A is maintained in the locked state.

  When the lock member 7A in the locked state is extracted, it is necessary to press the valve cover 4 against the valve box 2 side to compress the gasket 8 so as to eliminate or reduce the resistance of the lock member 7A to be pulled out due to the elastic restoring force of the gasket 8. .

  Therefore, even in the locked state, the resistance of the locking member 7A to be pulled out by the elastic restoring force of the gasket 8 is eliminated or reduced between the upper end surface 2g of the coupling outer fitting portion 2A and the lower surface of the valve lid body 4B of the valve lid 4. A gap is formed to allow the valve lid 4 to be pressed and moved to the compression side of the gasket 8 that is the side to be operated.

  Next, among the gate valves V1 connected to the water pipe 1 on the upstream side and the downstream side of the water pipe system, when the valve body 6 having a shorter life than the valve box 2 has reached the set durable life, or A valve lid removal method for removing the valve lid 4 provided with the valve body 6 and the valve stem 5 from the valve box 2 in an indefinite water state when a malfunction of the valve body 6 occurs will be described.

[1] FIG. 4 to FIG. 6 show the annular mounting base material B in a state in which the annular protrusion 9 formed integrally with the coupling outer fitting portion 2A of the valve box 2 is allowed to be inserted and removed from the locking member 7A. The base part attachment process which attaches attachment base part B1 in a watertight state is shown.

  The mounting base B itself has a mounting base B1 that is mounted in a watertight state at a position below the insertion / extraction operation position of the lock member 7A in the valve box 2, and at least a valve lid 4 that is mounted on the mounting base B1 in a watertight state. And an annular mounting frame B2 surrounding a part of the frame.

  The mounting base portion B1 includes a lower base member 15 having a split structure applied from the lower side of the protruding portion 9, a disk-shaped upper base member 16 applied from the upper side of the protruding portion 9, and both The base members 15 and 16 are constituted by second fastening means 17 for fastening the base members 15 and 16 to each other while holding them to the projection 9.

  Further, the lower base member 15 is divided into two parts at a substantially U-shaped or C-shaped divided lower plate portion 15A divided into two at the central position in the short side direction of the connecting outer fitting portion 2A of the valve box 2, It is composed of a connecting plate portion 15B projecting downward from both ends of the divided lower plate portion 15A, and a reinforcing plate portion 15C continuously provided across both the connecting plate portions 15B and the divided lower plate portion 15A. ing.

  On the upper surface of each divided lower plate portion 15A of the lower base member 15, as shown in FIG. 4, a substantially flat U-shaped half extending over one long side portion and half of both short side portions of the projection portion 9 is provided. In a state in which a fitting recess 15D that fits in the region is formed, and a bottom surface 15d of the fitting recess 15D and a substantially flat U-shaped side surface 15a continuous thereto are in contact with the lower surface and the peripheral surface of the protrusion 9, It is configured to prevent relative movement in the horizontal direction between the divided lower plate portions 15A and the protrusions 9.

  Further, the substantially flat U-shaped inner peripheral surface 15b of each divided lower plate portion 15A of the lower base member 15 is in contact with or close to the outer peripheral surface of the vertically oriented valve box portion 2D of the valve box 2. It is configured.

  In the center of the upper base member 16, a substantially rectangular (cornered rectangular) mounting hole 16A that can be externally mounted on the connecting external fitting portion 2A of the valve box 2 is formed through, and the upper base member As shown in FIG. 8, each of the first bolt insertion holes 15 e formed on the lower surface of the member 16 and on each divided lower plate portion 15 </ b> A of the lower base member 15 has a first A screw hole 17B for the bolt 17A of the second fastening means 17 inserted from below into the bolt insertion hole 15e is formed.

  Further, as shown in FIG. 8, the seal mounting groove 16 a formed on the lower surface of the upper base member 16 and corresponding to the upper surface of the protrusion 9 is fastened and fixed by the bolt 17 </ b> A of the second fastening means 17. An O-ring 19, which is an example of a sealing material that makes the space between the lower surface of the upper base member 16 and the upper surface of the protruding portion 9 watertight, is attached.

  In this base part attaching step, as shown in FIG. 4, the lower base member 15 is divided into two parts with respect to the annular projecting part 9 formed integrally with the connection fitting part 2 </ b> A of the valve box 2. The side plate portion 15A is mounted and operated from the short side direction of the protruding portion 9 (in the direction of the pipe axis of the water pipe 1), and the bottom surface 15d of the fitting recess 15D and the substantially flat U-shaped side surface 15a of each divided lower plate portion 15A. The protrusion 9 is brought into contact with the lower surface and the peripheral surface.

  The bolts 18A and nuts of the third fastening means 18 in which the connecting plate portions 15B of the two divided lower plate portions 15A facing each other in this state are inserted into the second bolt insertion holes 15f formed in the connecting plate portion 15B. After tightening and fixing at 18B, the mounting hole 16A of the upper base member 16 is externally mounted on the connecting external fitting portion 2A of the valve box 2, and inserted into the first bolt insertion hole 15e of the lower base member 15 from below. The bolt 17A is screwed into the screw hole 17B of the upper base member 16, and the upper base member 16 and the lower base member 15 are fastened and fixed to the protrusion 9 in a clamped state.

[2] FIG. 7, FIG. 9, and FIG. 10 show a pressing member that is detachably attached to the valve lid 4 by the first pressing jig C1 of the pressing means C provided in the mounting base portion B1 of the mounting base B. By pressing the valve lid 4 against the valve box 2 via 21, the gasket 8 provided between the coupling inner fitting portion 4 </ b> A of the valve lid 4 and the coupling outer fitting portion 2 </ b> A of the valve box 2 is in a watertight state. The locking member 7A of the locking means 7 is pulled out in a state where the first pressing step to be maintained and the pull-out resistance due to the elastic restoring force of the gasket 8 are eliminated or reduced, and the connecting external fitting portion 2A of the valve box 2 is extracted. And the unlocking step of releasing the fixed connection between the connecting inner fitting portion 4A of the valve lid 4.

  In FIGS. 8 to 10 and 12, a part of the shape shown in FIGS. 1 to 7 is simplified.

  Further, in the valve lid pressing step by the pressing means C, the valve lid 4 is valved by the first pressing jig C1 provided in the region corresponding to the internal space of the annular mounting frame B2 in the mounting base B1 before the annular mounting frame B2. After the first pressing step for pressing and fixing to the box 2 side and the mounting of the annular mounting frame B2, the valve lid 4 is mounted on the valve box 2 side by the second pressing jig C2 provided on the annular mounting frame B2 and operable from the outside. And a second presser step for pressing and fixing to the head.

  The pressing member 21 used in the valve lid pressing step is a disc that can be stably mounted in a horizontal posture parallel to the upper surfaces of the pair of mounting brackets 4E of the valve lid 4 protruding upward from the mounting hole 16A of the upper base member 16. The presser member 21 has four ends in the circumferential direction at both ends of a substantially U-shaped contact member 22 applied from the lower side to each suspension hook 4D of the valve lid 4. A third bolt insertion hole 21 a for fastening and fixing the portion with the bolt 23 is formed.

  The lower surface of the pressing member 21 is formed with a contact projection 21b that abuts the upper surface of each hanging hook 4D, and screw holes 22a for the bolts 23 are formed at both ends of each contact member 22.

  A through hole 21c from which the rotation operation portion 5a of the valve stem 5 protrudes is formed at the center of the presser member 21, and the valve body 6 and the valve stem 5 are provided at the peripheral portion of the through hole 21c on the upper surface of the presser member 21. A connected portion 21D that is detachably connected to the connecting portion 51 on the lifting and lowering conveying means D side that lifts and lowers the provided valve lid 4 and the like is formed.

  The connecting portion 51 on the up-and-down conveying means D side is configured as a connecting cylinder portion having a female screw formed on the inner periphery, and the connected portion 21d of the pressing member 21 is connected to a male screw formed on the outer periphery. It is comprised by the cylinder part.

  Further, to constitute the first pressing jig C1 of the pressing means C, as shown in FIG. 7 and FIG. 10B, on both sides of the central portion in the long side direction of the mounting hole 16A on the upper surface of the upper base member 16. A pair of first screw cylinders 25 forming female threads are fixed, and both first screw cylinders 25 are inserted into fourth bolt insertion holes 21e formed at two locations in the circumferential direction of the pressing member 21. The bolts 26 are screwed and fixed with locking nuts 27, and the valve lid 4 is attached to the upper side of each bolt 26 in accordance with the tightening operation in a state of being in contact with the upper surface of the presser member 21. A push nut 28 that is pressed against and fixed to is screwed together.

  The maximum pressing movement allowance of the valve lid 4 by the nut 28 of the first pressing jig C1 is such that the lock member 7A is connected to the outer engagement hole 7B and the valve lid in the coupling outer fitting portion 2A of the valve box 2 as shown in FIG. 4 is formed between the upper end surface 2g of the coupling outer fitting portion 2A and the lower surface of the valve lid body 4B of the valve lid 4 in the locked state engaged with the inner engagement recess 7C in the coupling inner fitting portion 4A. The gap 8 is set to have a compressible gap size.

  The gasket 8 is moved between the tapered surface 4a of the coupling inner fitting portion 4A of the valve lid 4 and the tapered surface 2f of the coupling outer fitting portion 2A of the valve box 2 by the tightening operation by the pushing nut 28 of the first pressing jig C1. In the compressed state, the insertion / removal resistance due to the elastic restoring force of the gasket 8 acting on the lock member 7A can be eliminated or reduced.

  Moreover, at this time, as shown in FIG. 10A, the lower end edge of the outer engagement hole 7B in the coupling outer fitting portion 2A of the valve box 2 is flush with the upper surface of the upper base member 16 or above it. The outer surface of the lock member 7A that is located and appears outside from the outer engagement hole 7B of the coupling outer fitting portion 2A of the valve box 2 is along the portion along the short side direction and the long side direction of the coupling outer fitting portion 2A. Therefore, the lock member 7A can be reliably and smoothly extracted with a light operating force.

[3] FIGS. 11 and 12 show a height at which the upper base member 16 of the mounting base portion B1 of the mounting base B can surround the entire circumference of the valve lid 4, that is, the valve stem from the upper surface of the upper base member 16. A step of attaching the cylindrical annular mounting frame B2 having a height higher than the height of the rotational operation portion 5a to the upper end of the rotational operation portion 5a in a watertight state, and after mounting the annular mounting frame B2, the annular mounting frame B2 A second presser step for pressing and fixing the valve lid 4 to the valve box 2 side with the second presser jig C2 of the presser means C that can be operated from the outside, and after the pressing and fixing by the second presser jig C2 is completed. The process of releasing the pressing and fixing by the nut 28 of the first pressing jig C1 is shown.

  As described above, although the shift from the first pressing jig C1 to the second pressing jig C2 is performed, the pressing and fixing of the valve lid 4 by the pressing means C is continuously performed.

  The connection flange 31 formed at the lower end of the cylindrical case body 30 constituting the annular mounting frame B2 has a sixth bolt insertion hole 31a at a portion corresponding to the fifth bolt insertion hole 16b formed in the upper base member 16. The seal mounting groove 31b formed on the lower surface of the connecting flange 31 is formed with bolts 32A. 4 of the fourth fastening means 32 inserted into the fifth and sixth bolt insertion holes 16b, 31a. An O-ring 33, which is an example of a sealing material that makes the space between the upper surface of the upper base member 16 and the lower surface of the connecting flange 31 in a tightening and fixing operation with the nut 32B, is mounted.

  The second presser jig C2 of the presser means C includes screw cylinders 35 communicating with the internal space of the cylindrical case body 30 at a plurality of circumferential positions (four positions in the present embodiment) of the cylindrical case body 30 and screw shafts thereof. The core is fixed in a state where the core is positioned on a horizontal axis that passes through or near the upper surface of the presser member 21, and each screw cylinder 35 is horizontally aligned with a tapered surface 21 f formed on the outer peripheral edge of the upper surface of the presser member 21. It is comprised by screwing in the pushing volt | bolt 36 provided with the taper-shaped pressing surface 36a contact | abutted from.

  In the state where the valve lid 4 is pressed and fixed to the valve box 2 side by the tightening operation of the plurality of pressing bolts 36 of the second pressing jig C2, the pressing force by the nut 28 of the first pressing jig C1 is released. However, the gasket 8 interposed between the tapered surface 4a of the coupling inner fitting portion 4A of the valve lid 4 and the tapered surface 2f of the coupling outer fitting portion 2A of the valve box 2 is maintained in a compressed watertight state. The

  Therefore, after the pressing and fixing by the second pressing jig C <b> 2 is completed, the pressing and fixing by the nut 28 of the first pressing jig C <b> 1 is released from the upper opening of the cylindrical case body 30.

[4] FIG. 13 shows a housing mounting step in which the work housing H provided with the lifting and lowering conveying means D connected to the work opening / closing valve V2 and the valve lid 4 is attached to the annular mounting frame B2 of the mounting base B in a watertight state. Show.

  Of the valve case 40 of the work opening / closing valve V2, the inner surface of the fitting mounting cylinder portion 40A that is mounted on the cylindrical case body 30 of the annular mounting frame B2 from above is fitted on the upper end surface of the cylindrical case body 30. As shown in FIG. 12, the cylindrical case body 30 is provided with annular fittings 40a for fitting position regulation that are in contact with each other from above, and at a plurality of locations in the circumferential direction of the fitting mounting cylinder portion 40A of the valve case 40. A pulling bolt 41 having a tapered pressing surface 41a that abuts in a horizontal direction against a lower tapered surface 30b of an annular protrusion 30a formed to protrude from the upper end portion of the outer peripheral surface is screwed.

  In addition, between the facing surface between the inner corner formed by the inner surface of the fitting mounting cylinder portion 40 </ b> A and the fitting position regulating annular protrusion 40 a in the valve case 40 and the upper tapered surface 30 c of the annular protrusion 30 a of the cylindrical case body 30. Is attached with an O-ring (not shown) which is an example of a sealing material, and the fitting protrusions 40a of the valve case 40 are restrained by compressing the O-ring into a watertight state by tightening the pulling bolt 41. Is pulled and fixed to the upper end surface of the cylindrical case body 30 of the annular mounting frame B2.

  The work housing H includes a work housing main body 43 having a lower connection flange 43A fixedly connected to the upper connection flange 40B of the valve case 40 by a bolt 42A and a nut 42B of the fifth fastening means 42 in a watertight state, and the work housing. The main body 43 includes a canopy 45 fixedly connected to the upper flange 43B of the main body 43 in a watertight state by bolts 44A and nuts 44B of the sixth fastening means 44.

  A storage space S in which the valve lid 4 including the valve body 6 and the valve stem 5 can be stored is formed in the work housing main body 43.

  In order to constitute the lifting / lowering conveying means D, a lifting / lowering shaft 52 is slidably supported in a vertical direction through a cylindrical shaft support 50 provided at the center of the canopy 45 of the work housing H. A connecting portion 51 is provided at the lower end portion of the presser member 21 so as to be detachably connected to the connected portion 21d of the presser member 21, and the valve body 6 and the valve rod are provided at the upper end portion of the lifting shaft 52. 5 is moved up into the storage space S of the work housing main body 43 by a crane or the like, or the work housing main body 43 in which the valve cover 4 is stored is suspended and conveyed to a predetermined place by a crane or the like. A suspension ring 53 is provided.

  Further, the mounting plate portion 56 formed on the upper end portion of the shaft support portion 50 so as to face both ends of the lifting operation rod 55 fastened and fixed to the upper portion of the lifting shaft 52 with a nut 54 in the vertical direction. In order to attach another valve lid 4 or a new lid 60 to the valve box 2 after the valve lid 4 is removed, the working housing main body 43 is placed at a predetermined storage position in the storage space S. A screw-type forced feeding mechanism 57 is provided for lowering another valve lid 4 or a new lid 60 against the water pressure.

  The screw-type forced feed mechanism 57 abuts on both ends of the mounting plate portion 56 of the shaft support portion 50 with a long bolt 57B that is fastened and fixed with a pair of nuts 57A and the upper surfaces of both ends of the lifting operation rod 55. It is comprised from the feeding nut 57C screwed together by each long volt | bolt 57B in the state.

  In this housing mounting step, the valve lid 4 is pressed and fixed to the valve box 2 side by the tightening operation of the plurality of pressing bolts 36 of the second pressing jig C2.

  As shown in FIG. 13, the valve lid 4 can be pressed and fixed to the valve box 2 side by using tightening of the feeding nut 57 </ b> C of the screw-type forced feeding mechanism 57.

[5] FIG. 14 shows a state in which the pressing and fixing by the second pressing jig C2 of the pressing means C is released, and the valve lid 4 is taken out into the storage space S of the working housing H by the lifting and lowering conveying means D, The process of closing the on-off valve V2 is shown.

  Specifically, the plurality of pressing bolts 36 of the second pressing jig C2 are loosened, and the tapered pressing surface 36a of each pressing bolt 36 is a tapered surface formed on the outer peripheral edge of the upper surface of the pressing member 21. 21f is disengaged radially outward.

  Thereafter, the valve lid 4 fitted to the valve box 2 is moved up to a predetermined storage position in the storage space S of the work housing main body 43 by a crane or the like connected to the lifting shaft 52 of the lifting / lowering conveying means D. Thereafter, the valve element 39 of the work on-off valve V2 is closed.

[6] FIG. 15 shows a step of removing the valve lid 4 taken out into the storage space S of the working housing H.
In this removal step, the bolt 42A and nut 42B of the fifth fastening means 42 that fixedly connects the upper connection flange 40B of the valve case 40 and the lower connection flange 43A of the work housing body 43 are removed, and the removed valve The work housing main body 43 provided with the lid 4 and the lifting and lowering conveying means D is suspended and conveyed to a predetermined position by a crane or the like and removed.

[7] When another valve lid 4 equipped with at least a new valve body 6 is to be attached after the removal process of the valve lid 4, a procedure substantially reverse to the above-described removal work process is performed.
That is, after the removal process of the valve lid 4,
Connecting at least a connected portion 21d of another valve lid 4 equipped with a new valve body 6 to the connecting portion 51 of the lifting shaft 52 of the lifting and lowering conveying means D provided in the work housing H;
Step of fixing and connecting the lower connection flange 43A of the work housing main body 43 of the work housing H and the upper connection flange 40B of the valve case 40 of the work on / off valve V2 in a watertight state with the bolts 42A and nuts 42B of the fifth fastening means 42 When,
After opening the valve body 39 of the work on-off valve V2, the feed nut 57C of the screw-type forced feed mechanism 57 is tightened to operate another valve lid 4 in the storage space S of the work housing H. A step of lowering to the valve box 2 side integrally with the lifting / lowering shaft 52, and fitting and connecting the coupling inner fitting portion 4A of another valve lid 4 to the coupling outer fitting portion 2A of the valve box 2,
A step of pressing and fixing another valve lid 4 to the valve box 2 side with the second presser jig C2 of the presser means C;
After rotating the lifting shaft 52 to the screw release side to release the connection between the connecting portion 51 of the lifting shaft 52 and the connected portion 21d of another valve lid 4, the cylindrical case body 30 of the annular mounting frame B2 A work housing provided with the work open / close valve V2 and the lifting / lowering conveying means D from the cylindrical case body 30 of the annular mounting frame B2 by unlocking the pulling bolt 41 fixedly connected to the valve case 40 of the work open / close valve V2. Removing H,
A step of fixing and connecting a coupling inner fitting portion 4A of another valve lid 4 fitted and connected to a coupling outer fitting portion 2A of the valve box 2 by a lock member 7A of the locking means 7;
The pressing of the other valve lid 4 by the pressing bolt 36 of the second pressing jig C2 is released, and the connecting flange 31 of the cylindrical case body 30 of the annular mounting frame B2 and the upper base member 16 of the mounting base portion B1 are fixedly connected. Removing the annular mounting frame B2 from the mounting base B1,
In a state where the holding member 21 and the abutting member 22 are fixedly connected to each hanging hook 4D of another valve lid 4, the fixing operation of the bolt 23 that fixes and connects the holding member 21 and the abutting member 22 is performed. Removing the member 22;
The bolt 17A of the second fastening means 17 that fixes and connects the upper base member 16 and the lower base member 15 of the mounting base B1 is unlocked, and the upper base member 16 and the lower base member 16 are projected from the protrusion 9 of the valve box 2. Removing the side base member 15;
Execute.

  In this first embodiment, at least the coupling inner fitting portion 4A of another valve lid 4 equipped with a new valve element 6 is fitted and connected to the coupling outer fitting portion 2A of the valve box 2 to lock the locking means 7. By connecting the connecting inner fitting portion 4A of another valve lid 4 and the connecting outer fitting portion 2A of the valve box 2 by the insertion operation of the member 7A, the valve body 6 that has reached the set endurance life or malfunction is caused. The gate valve V1 provided with the generated valve body 6 and the like can be efficiently renewed while reducing the construction cost.

  After another valve lid 4 connected to the lifting and lowering conveying means D of the work housing H is lowered, and the connecting inner fitting portion 4A thereof is fitted and connected to the connecting outer fitting portion 2A of the valve box 2. The removal work process in the first embodiment described above is executed in the reverse procedure, and over the coupling inner fitting portion 4A of another valve lid 4 fitted and connected and the coupling outer fitting portion 2A of the valve box 2. The locking member 7A of the locking means 7 may be inserted and operated. However, the lifting / lowering conveying means D can press and fix another valve lid 4 to the valve box 2 in a watertight state, and the mounting base B When a work window or work arm capable of inserting and operating the lock member 7A from the outside is provided, the lifting / lowering conveyance is performed without performing the steps in the first feature configuration in the reverse procedure. When another valve lid 4 is pressed and fixed to the valve box 2 in a watertight state by means D, And a connection-fitting portion 2A of the connecting the mating portion 4A and the valve body 2 of another valve cover 4 that is if connected may be fixedly connected with the locking member 7A.

[Second Embodiment]
In the first embodiment described above, another valve lid 4 equipped with at least a new valve element 6 is attached to the valve box 2, but as shown in FIG. You may attach the cover body 60 which closes 2 valve body mounting | wearing opening parts 3 in a watertight state.

In this second embodiment, after the removal step of the valve lid 4 of the first embodiment,
A step of connecting a connected portion of the lid body 60 in which the plug 61 is attached to the cylindrical portion 60a of the central portion to the connecting portion of the lifting shaft 52 of the lifting and lowering conveying means D provided in the work housing H;
A step of fixing and connecting the lower connection flange 43A of the work housing main body 43 in the work housing H and the upper connection flange 40B of the valve case 40 in the work on-off valve V2 in a watertight state with the bolts 42A and nuts 42B of the fifth fastening means 42. When,
After opening the valve body 39 of the work on-off valve V2, the feed nut 57C of the screw-type forced feed mechanism 57 is tightened, and the lid body 60 in the storage space S of the work housing H is moved up and down. A step of lowering to the valve box 2 side integrally with the shaft 52 and fitting and connecting the coupling inner fitting part 60A of the lid 60 to the coupling outer fitting part 2A of the valve box 2;
A step of pressing and fixing the lid 60 to the valve box 2 side with the second pressing jig C2 of the pressing means C;
After releasing the connection between the connecting portion of the elevating shaft 52 and the connected portion of the lid 60, the pulling bolt that fixedly connects the cylindrical case body 30 of the annular mounting frame B2 and the valve case 40 of the work on-off valve V2. A step of unlocking 41 and removing the work housing H provided with the work on-off valve V2 and the lift conveying means D from the cylindrical case body 30 of the annular mounting frame B2,
A step of fixing and connecting the coupling inner fitting portion 60A of the lid body 60 fitted and connected to the coupling outer fitting portion 2A of the valve box 2 by the lock member 7A of the locking means 7;
The pressing of the lid body 60 by the pressing bolt 36 of the second pressing jig C2 is released, and the connecting flange 31 of the cylindrical case body 30 of the annular mounting frame B2 and the upper base member 16 of the mounting base portion B1 are fixedly connected. A step of releasing the fourth fastening means 32 and removing the annular mounting frame B2 from the mounting base B1;
The bolt 17A of the second fastening means 17 that fixes and connects the upper base member 16 and the lower base member 15 of the mounting base B1 is unlocked, and the upper base member 16 and the lower base member 16 are projected from the protrusion 9 of the valve box 2. Removing the side base member 15;
Execute.

  Further, in the seal mounting groove formed on the outer peripheral surface of the connecting inner fitting portion 60A of the lid body 60, the connecting inner fitting portion 60A of the lid body 60 is fitted and attached to the connecting outer fitting portion 2A of the valve box 2. The gasket 8 which is an example of the annular sealing material compressed between both the taper surfaces 60b and 2f is mounted so as to make the space between the taper surfaces 60b and 2f watertight when the fitting operation is performed to the position.

  In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment, the same number is attached to the same structure location as 1st Embodiment, and the description is abbreviate | omitted.

  In addition, after the connecting inner fitting portion 60A of the lid body 60 connected to the lifting and lowering conveying means D of the work housing H is operated to be fitted and connected to the connecting outer fitting portion 2A of the valve box 2, the above-described first operation is performed. The lock member 7 </ b> A of the locking means 7 is carried out across the connecting inner fitting portion 60 </ b> A of the lid body 60 and the connecting outer fitting portion 2 </ b> A of the valve box 2, which are executed in substantially reverse order. The lid body 60 can be pressed and fixed to the valve box 2 in a watertight state by the lifting and lowering conveying means D, and the lock member 7A is inserted into the mounting base B from the outside thereof. When a work window, work arm, or the like that can be operated is installed, the lid 60 is valved by the lifting and lowering conveying means D without performing the steps in the first characteristic configuration in the reverse approximate order. When the box 2 is pressed and fixed in a watertight state, it is fitted and connected. And a connection-fitting portion 2A of the connecting the mating portion 60A and the valve body 2 of the cover 60 may be fixedly connected with the locking member 7A which are.

[Third Embodiment]
In the first embodiment described above, another valve lid 4 equipped with at least a new valve element 6 is attached to the valve box 2. However, as shown in FIG. You may attach the assembly E of V3 and the valve attachment member 66 provided with the connection internal fitting part 66B which can be fitted and connected to the connection external fitting part 2A of the valve box 2. FIG.

  In this assembly E, the lower connection flange 65A of the valve case 65 of the repair valve V3 and the connection flange 66A of the valve mounting member 66 are fixedly connected in a watertight state by bolts and nuts of fastening means (not shown).

In the third embodiment, after the removal step of the valve lid 4 of the first embodiment,
Connecting a connected portion provided on the repair valve V3 of the assembly E to a connecting portion of the lifting shaft 52 of the lifting and lowering conveying means D provided in the work housing H;
A step of fixing and connecting the lower connection flange 43A of the work housing main body 43 in the work housing H and the upper connection flange 40B of the valve case 40 in the work on-off valve V2 in a watertight state with the bolts 42A and nuts 42B of the fifth fastening means 42. When,
After opening the valve body 39 of the work on / off valve V2, the feed nut 57C of the screw-type forced feed mechanism 57 is tightened to raise and lower the assembly E in the storage space S of the work housing H. A step of lowering to the valve box 2 side integrally with the shaft 52 and fitting and connecting the coupling inner fitting portion 66B of the valve mounting member 66 to the coupling outer fitting portion 2A of the valve box 2;
A step of pressing and fixing the valve mounting member 66 to the valve box 2 side with the second pressing jig C2 of the pressing means C;
After releasing the connection between the connecting portion of the lift shaft 52 and the connected portion of the assembly E, the pulling bolt that fixedly connects the cylindrical case body 30 of the annular mounting frame B2 and the valve case 40 of the work on-off valve V2. A step of unlocking 41 and removing the work housing H provided with the work on-off valve V2 and the lift conveying means D from the cylindrical case body 30 of the annular mounting frame B2,
A step of fixing and connecting the coupling inner fitting portion 66B of the fitted valve mounting member 66 and the coupling outer fitting portion 2A of the valve box 2 with the locking member 7A of the locking means 7;
The pressing of the valve mounting member 66 by the pressing bolt 36 of the second pressing jig C2 is released, and the connecting flange 31 of the cylindrical case body 30 of the annular mounting frame B2 and the upper base member 16 of the mounting base portion B1 are fixedly connected. Removing the annular mounting frame B2 from the mounting base B1,
The bolt 17A of the second fastening means 17 that fixes and connects the upper base member 16 and the lower base member 15 of the mounting base B1 is unlocked, and the upper base member 16 and the lower base member 16 are projected from the protrusion 9 of the valve box 2. Removing the side base member 15;
Execute.

  Further, in the seal mounting groove formed on the outer peripheral surface of the coupling inner fitting portion 66B of the valve mounting member 66, the coupling inner fitting portion 66B of the valve mounting member 66 is fitted to the coupling outer fitting portion 2A of the valve box 2 with a predetermined fit. When the fitting operation is performed to the mating mounting position, the gasket 8 which is an example of the annular sealing material compressed between the two tapered surfaces 66a and 2f is mounted so as to make the space between the tapered surfaces 66a and 2f watertight. Yes.

  In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment, the same number is attached to the same structure location as 1st Embodiment, and the description is abbreviate | omitted.

  Further, the assembly E of the repair valve V3 and the valve mounting member 66 connected to the lifting and lowering conveying means D of the work housing H is lowered to connect the connection fitting portion 66B of the valve mounting member 66 to the valve box 2. After fitting and connecting to the outer fitting portion 2A, the steps in the first characteristic configuration described above are executed in a substantially reverse order, and the coupling inner fitting portion 66B and the valve fitting member 66B of the valve mounting member 66 that are fitted and connected are connected. The locking member 7A of the locking means 7 may be inserted and operated across the connecting outer fitting portion 2A of the box 2, but the valve mounting member 66 can be pressed and fixed to the valve box 2 in the watertight state by the lifting and lowering conveying means D. In addition, when the mounting base material B is equipped with a work window, a work arm, or the like capable of inserting and operating the lock member 7A from the outside thereof, the process of the first characteristic configuration described above is substantially reversed. Lifting hand without performing in order When the valve mounting member 66 is pressed and fixed to the valve box 2 in a watertight state in D, the coupling inner fitting part 66B of the valve mounting member 66 and the coupling outer fitting part 2A of the valve box 2 are locked together. You may comprise so that it may be fixedly connected by 7A.

[Other Embodiments]
(1) In the above-described embodiment, the annular mounting base material B is held in a state of being held at the lower end portion of the outer peripheral surface of the coupling outer fitting portion 2A of the valve box 2 that is biased downward from the insertion / removal operation position of the lock member 7A. Although the attachable annular protrusion 9 is integrally formed, the protrusion 9 may be formed intermittently in the circumferential direction of the connection fitting part 2A of the valve box 2.

  (2) In the above-described embodiment, the locking means 7 includes the plate-like lock member 7A, the outer engagement hole formed in the coupling outer fitting portion 2A of the valve box 2, and the coupling inner fitting of the valve lid 4. The inner engagement recess 7C formed in the portion 4A is not limited to this structure, but the outer engaged portion formed in the connection outer fitting portion 2A of the valve box 2 and the valve lid 4 Any structure may be used as long as the lock member 7A can be inserted into and removed from the inner engaged portion formed in the coupling inner fitting portion 4A.

  (3) In the above-described embodiment, the annular mounting base B that is attached to the valve box 2 in a state in which the insertion / extraction operation of the lock member 7A is allowed is lower than the insertion / extraction operation position of the lock member 7A in the valve box 2. The mounting base portion B1 attached to the part in a watertight state and the annular mounting frame B2 surrounding at least a part of the valve lid 4 attached to the mounting base portion B1 in a watertight state are separately configured. B1 and the annular mounting frame B2 may be configured integrally.

  (4) In the above-described embodiment, the first pressing jig C1 provided with the pressing means C for pressing the valve lid 4 against the valve box 2 in the region corresponding to the inner space of the annular mounting frame B2 in the mounting base portion B1, Although it comprised from the 2nd holding jig C2 which can be operated from the outside provided in the annular attachment frame B2, you may comprise from one holding jig.

  (5) In the above-described embodiment, the flange junction type gate valve V1 provided with the connecting flange 2B for the upstream and downstream water pipes 1 is described as an example, but at least one end side is a receiving port or an insertion port. The gate valve V1 comprised in this may be sufficient.

  (6) Form of the fitting connection part A between the valve box 2 and the valve lid 4, form of the mounting base B, form of the pushing means C, form of the housing H, form of the lifting and lowering conveying means D, work on-off valve Each of the forms of V2 can be appropriately changed according to various conditions.

  As described above, the valve lid removal method of the gate valve that can efficiently and easily perform the work of removing the valve lid provided with the valve body and the valve stem in an indefinite water state while reducing the construction cost, and Therefore, it is possible to provide a gate valve that contributes to streamlining and facilitating the removal work.

A fitting connection B mounting base B1 mounting base B2 annular mounting frame C pressing means C1 first pressing jig C2 second pressing jig D lifting / lowering conveying means E assembly H work housing S storage space V1 gate valve V2 work Open / close valve for valve V3 Repair valve 2 Valve box 2A Connection outer fitting part 3 Valve body mounting port part 4 Valve lid 4A Connection internal fitting part 5 Valve rod 6 Valve body 7 Locking means 7A Locking member 9 Protruding part 21 Holding member 60 Lid 60A Connection fitting part 66 Valve mounting member 66A Connection fitting part

Claims (8)

A valve box connected to the fluid piping system, a valve lid fitted and connected to the valve box, and a valve rod penetrating the valve lid are detachably mounted from the valve body mounting port. Lock member that can be inserted and removed from the outside with respect to the valve body side, the valve box side connection fitting part and the valve cover side connection fitting part that constitute the fitting connection part of the valve body and the valve lid. And a valve provided with the valve body and the valve stem, in a gate valve provided with a locking means for fixing and connecting the valve box and the valve lid in a watertight state in the engaged state in which the lock member is inserted. It is a valve lid removal method for a gate valve that removes the lid from the valve box in a state of constant water,
Attaching the annular attachment base material to the valve box in a watertight state in a state allowing the lock member to be inserted and removed;
By pressing the valve lid against the valve box by the pressing means provided on the mounting base material, the space between the coupling inner fitting portion of the valve lid and the coupling outer fitting portion of the valve box is maintained in a watertight state. Process,
Extracting the locking member of the locking means, and releasing the fixed connection between the connection fitting part of the valve box and the connection fitting part of the valve lid;
Attaching a work housing provided with a lifting and lowering conveying means connected to the work opening and closing valve and the valve lid to the attachment base material in a watertight state;
Releasing the pressing and fixing of the presser means, and taking out the valve lid into the storage space of the work housing by the lifting and lowering means, and then closing the work on-off valve; and
Removing the valve lid taken out in the storage space of the working housing;
The valve lid removal method of the gate valve equipped with.   The valve lid removal method of a gate valve according to claim 1, wherein the pressing means is configured to press the valve lid against the valve box via a pressing member that is detachably attached to the valve lid.   The valve lid removal method of a gate valve according to claim 1 or 2, wherein the mounting base material is clamped and fixed to a projecting portion that is formed to project downward from a position of the lock member in the valve box.   The mounting base is mounted in a watertight state at a position below the insertion / extraction operation position of the lock member in the valve box in a watertight state, and at least a part of the valve lid is mounted in the watertight state on the mounting base. A first holding jig provided in a region corresponding to the inner space of the annular mounting frame in the mounting base portion before the mounting of the annular mounting frame. The step of pressing and fixing the valve lid to the valve box side, and after the mounting of the annular mounting frame, the valve lid is pressed to the valve box side by a second presser jig provided on the annular mounting frame that can be operated from the outside. The valve lid removal method of the gate valve of any one of Claims 1-3 comprised from the process to fix. After the removal process of the valve lid,
Connecting another valve lid equipped with at least a new valve body to the lifting and lowering conveying means provided in the work housing;
Opening the work on / off valve, another valve lid in the storage space of the work housing is lowered to the valve box side by the lifting and lowering conveying means, and a connection fitting portion of the other valve lid is installed. A step of fitting and connecting to a coupling outer fitting portion of the valve box;
A step of fixing and coupling a coupling inner fitting portion of another valve lid that is fitted and connected to a coupling outer fitting portion of the valve box with a locking member of the locking means;
The valve lid removal construction method of the gate valve according to any one of claims 1 to 4, wherein: After the removal process of the valve lid,
Connecting the lid for closing the valve body mounting port of the valve box in a watertight state to the lifting and lowering conveying means provided in the work housing;
The opening / closing valve for the operation is opened, and the lid in the storage space of the working housing is lowered to the valve box side by the lifting and lowering conveying means, and the connection fitting portion of the lid is connected to the valve box A step of fitting and connecting to the outer fitting portion;
A step of fixing and connecting the coupling inner fitting portion of the lid body fitted and connected and the coupling outer fitting portion of the valve box with the locking member of the locking means;
The valve lid removal construction method of the gate valve according to any one of claims 1 to 4, wherein: After the removal process of the valve lid,
Connecting the assembly of the repair valve and the valve mounting member provided with the coupling inner fitting portion that can be fitted and connected to the coupling outer fitting portion of the valve box to the lifting and lowering conveying means provided in the work housing;
Opening the work on / off valve, the assembly in the storage space of the work housing is lowered to the valve box side by the lifting and lowering conveying means, and the connection fitting part of the valve mounting member is connected to the valve box. A step of fitting and connecting to the outer fitting portion;
A step of fixing and coupling the coupling inner fitting portion of the valve mounting member fitted and connected to the coupling outer fitting portion of the valve box with the locking member of the locking means;
The valve lid removal construction method of the gate valve according to any one of claims 1 to 4, wherein: A valve box connected to the fluid piping system, a valve lid fitted to and coupled to the valve box, and a valve rod penetrating the valve lid are detachably mounted from the valve body mounting port. A gate valve provided with a valve body,
The fitting connection part between the valve box and the valve lid is detachable from the outside with respect to the connection outer fitting part on the valve box side and the connection inner fitting part on the valve lid side constituting the fitting connection part. In the engaged state where the lock member is inserted and in which the lock member is inserted, there is provided a lock means for fixing and connecting the valve box and the valve lid in a watertight state. A gate valve in which a projecting portion to which an annular mounting base material can be attached is integrally formed at a portion biased downward from the position.

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