JPH07103952B2 - Valve with hot tap fitting - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve which is inserted into a pipe by a hot tap method.

[0002]

2. Description of the Related Art The easiest way to insert a valve into an existing piping line is to stop the flow of the piping line and insert the valve, but it is troublesome to contact the customer and investigate the usage situation. Therefore, recently, the pressure inside the pipe has not dropped,
Moreover, a hot tap construction method in which a valve is inserted into a piping line without stopping the flow of fluid is performed, and an example thereof is a construction method described in Japanese Patent Publication No. 48-27244.

An outline of the hot tap method will be described with reference to FIGS. 17 to 33. This hot tap method is
As shown in FIG. 17, the ground on both sides of the valve insertion location 6 of the pipe 5 is excavated, and fittings 1 and 1 are attached to the upstream side and the downstream side of the valve insertion location 6 of the pipe 5, respectively. As shown in FIG. 18, it is divided into an upper fitting 2 and a lower fitting 3, and the upper fitting 2 further includes a neck fitting 1.
7 is attached by welding 23.

The neck fitting 17 is provided with a flange 2a, the flange 2a is provided with screw holes 22 at several places, and an internal thread 18 is provided on the inner edge.
The female screw 18 is formed so as to be screwed with the male screw 19 of the seal plug 4.

As shown in FIG. 19, the upper fitting 2 and the lower fitting 3 are welded to the outer periphery of the pipe 5 by fillet welding 20, and the upper fitting 2 and the lower fitting 3 are bonded by butt welding 21. .

Next, as shown in FIG. 20, the flange 2a
The gate valve 7 and the punching machine 8 are sequentially attached on the top of the pipe, the gate valve 7 is opened, and the cylindrical cutter 9 formed to have a diameter larger than that of the pipe 5 is rotated by a driving source (not shown) to flow the fluid. Cut the open tube 5. Then, the cut portion of the pipe 5 is held by the holding tool 9a in the cutter 9, and is pulled up together with the cutter 9 to be housed in the punching machine 8.

Next, the gate valve 7 is closed, the punching machine 8 is removed from the gate valve 7, and as shown in FIG. 21, the stopping valve 10 equipped with the stopper 11 is attached to the gate valve 7 to seal it, and then again. The gate valve 7 is opened, and the stopper 11 is inserted into the cut portion of the tube 5. Then, as shown in FIG. 24, the stopper 11 to be inserted directs the slit 12 toward the side where the fluid is flowing.

The above cutting and insertion of the stopper 11 are carried out for each fitting 1, and as shown in FIG. 22, the bypass outlets 15 and 15 provided in both stopping machines 10 and 10 are connected. Bypass circuit 1
6 is provided.

As shown in FIG. 23, the stopper 11 is composed of a cylinder 13 having a rubber 12 attached to its outer surface and having a slit 12. The outer diameter of the rubber 14 is smaller than the outer diameter of the cutter 9. In this state, the tube 5 is inserted into the cut portion, and then the stopping machine 10 is operated to expand the stopper 11 in the radial direction by a mechanism (not shown) to bring the rubber 14 of the stopper 11 into close contact with the cut portion.

The specific structure of the stopper 11 is described in Japanese Patent Publication No. 48-27244. Then, the fluid becomes slit 1 of the stopper 11 on the upstream side.
2 enters the stopper 11, passes through the upstream stopping machine 10, enters the downstream stopping machine 10 through the bypass circuit 16, passes through the slit 12 of the downstream stopper 11, and reaches the downstream pipe 5. And the valve insertion position 6 of the pipe 5 between the fittings 1 and 1.
Flow stops.

Therefore, the valve insertion location 6 of the pipe 5 is cut, and the valve 35 is inserted into the pipe 5 as shown in FIG. When the insertion of the valve 35 into the tube 5 is completed, the work reverse to the previous step is performed. That is, the stopping machine 10
Is operated to reduce the stopper 11, and the stopper 1
1 is collected in the stopping machine 10, the gate valve 7 is closed, and the bypass circuit 16 and the upstream and downstream stopping machines 10 and 10 are removed.

Next, the plug tightening machine 38 shown in FIG.
The plug fastener 38 is mounted on the gate valve 7. A shaft 39 is rotatably provided on the plug valve 38, and a male screw 40 is provided on the tip of the shaft 39.
An upper portion of the shaft 39 where the male screw 40 is provided is formed to have a small diameter as shown in FIG. 29, and a large-diameter stopper 42 is provided to the upper portion of the portion where the small diameter is formed. Further, smooth surfaces 45 are formed on both sides of the shaft 39 from the small diameter portion to the lower end portion.

Then, as shown in FIG. 29, the shaft 39
The screw tightening fork 37 fitted to is provided with a female screw 44 in which the male screw 40 of the shaft 39 can be screwed in the central portion. The screwing fork 37 is formed so as not to drop from the shaft 39 unless it is unscrewed from the male screw 40.

On the side of the screw tightening fork 37,
A screw hole 49 penetrating therethrough is provided, and a machine screw 46 is screwed into this screw hole 49.
The rotation of 9 is transmitted to the screw tightening fork 37.

The lower surface of the screw tightening fork 37 is shown in FIG.
As shown in FIG. 30, a pair of fastening claws 47 are provided. When the screw tightening fork 37 is rotated in a direction in which the seal plug 4 described later is screwed in, the fastening claws 47 are provided as shown in FIG. The tip end side of 47 is projected downward so as to be able to engage with the recess 48 of the seal plug 4, and when the screw tightening fork 37 is reversed, the rear end side of the fastening claw 47 can be pulled out from the recess 48 as shown in FIG. Further, the rear end side is formed so as to project short, and the lower surface of the fastening claw 47 is an inclined surface 50.

As shown in FIGS. 26 and 27, the seal plug 4 for sealing the upper portion of the fitting 1 has two recesses 48 on the upper surface thereof, and a flange-like portion provided on the peripheral edge of the upper end thereof on the lower side thereof. Is fitted with an O-ring 25, and a male screw 19 is provided below the O-ring 25.

Then, as shown in FIG. 29, the screw tightening fork 37 is externally fitted to the portion of the shaft 39 where the male screw 40 is provided and which is formed to have a small diameter, and the shaft 39 and the screw tightening fork 37 are fitted. So that they do not rotate with respect to each other, the machine screw 46 is screwed in such that the tip of the machine screw abuts the smooth surface 45, and the screw tightening fork 37 and
Between the stop 42 of the shaft 39, as shown in FIG.
The screw tightening fork 37 is urged downward.

Then, as shown in FIG. 26, the male screw 40 of the shaft 39 is screwed into the female screw 41 of the seal plug 4, the fastening claw 47 of the screw tightening fork 37 and the recess 48 of the seal plug 4 are engaged.
And the seal plug 4 is mounted on the shaft 39 of the plug tightening machine 38.

As described above, the plug fastening machine 38 with the seal plug 4 attached thereto is attached to the gate valve 7 as described above, and then the gate valve 7 is opened to open the plug fastening machine 38. When the shaft 39 is moved forward and the shaft 39 is rotated clockwise, the tip end side of the fastening claw 47 of the screw tightening fork 37 engages with the recess 48 of the seal plug 4, as shown in FIG.
The seal stopper 4 is rotated, and as shown in FIG. 31, the male screw 19 of the seal stopper 4 is screwed into the female screw 18 of the fitting 1 so that the seal stopper 4 is attached to the fitting 1 and the opening at the upper portion of the fitting 1 is opened. Seal.

Next, when the shaft 39 is rotated in the opposite direction, as shown in FIG. 32, the fastening claw 47 is pulled out from the recess 48 of the seal plug 4 by the inclined surface 50 of the lower surface, and the male screw 40 of the shaft 39 is also sealed. Since the screw 39 is unscrewed from the female screw 41 of the plug 4, the shaft 39 of the plug fastening machine 38 is disengaged from the seal plug 4 while the screw fastening fork 37 is attached.

Then, as shown in FIG. 33, the plug clamp 38 and the gate valve 7 are removed from the fitting 1, and the mounting of the valve 35 without stopping the flow of the fluid in the pipe 5 is completed. Furthermore, a concrete pit 36 is provided around the valve 35, and the upper surface of the portion where the fitting 1 is provided is formed flush with another road surface or the like, thus completing the construction. Then, the road surface has no protrusions and can be used as a road.

[0022]

In the conventional construction method, the pipe 5 buried in the city center can be constructed only at night due to road traffic. Therefore, the construction is carried out over a long period of time. However, it is not preferable from the viewpoint of keeping the calmness of the surrounding residents. Therefore, the construction period as short as possible was required.

During the operation of inserting the valve, the inside of the pipe 5 is sealed by the stoppers 11 on both sides of the valve, and the fluid is allowed to flow in the bypass circuit 16. However, the fluid has a reduced cross-sectional area in the slit 12 of the stopper 11 and is squeezed to generate pressure loss, and the bypass circuit 16 has a smaller cross-sectional area than the pipe 5. Therefore, the supply flow rate decreases, but the time of this flow rate decrease continues throughout the welding of the valve to the pipe.
There was a limit to the construction time.

For example, when the fluid is city gas, the time when the city gas consumption is low is selected and the operation is performed at night, or the operation is performed in the summer rather than in the winter. There was a problem of doing.

The present invention has been made in view of the above matters, and a valve to be mounted by using a hot tap fitting that can be inserted into a pipeline without being limited in construction time and construction time. To do this is a technical issue.

[0026]

According to the present invention, a fitting 1 is attached to the outer circumference of a pipe 5, and the pipe 5 inside the fitting 1 is fitted.
A cut portion 55 is provided on the end face 56 to form an end surface 56, and a sealing plug 65 having a shaft insertion hole 66 is fitted on a step portion 58 provided at the opening of the fitting 1. Is fixed by a plurality of set screws 61 screwed from the outer periphery of the above to seal the opening, and a central shaft 75 provided with a connecting screw 76 is rotatably tightly fitted and mounted in the shaft insertion hole 66, An upper male screw 80 is provided on the central shaft 75, and a lower male screw 81 inclined in the opposite direction to the upper male screw 80 is provided below the upper male screw 80. Vertical holes 87 are formed in the upper male screw 80 and the lower male screw 81, respectively. The provided upper screw cylinder 83 and the lower screw cylinder 88 are screwed together, and the vertical hole 87 is externally fitted to the rod 70 hung from the sealing plug 65 so as to be vertically slidable. The lower screw cylinder 88 has the opposite inclination directions. A tapered surface 86 and a lower tapered surface 90 are provided, a flat plate 85 is attached, the contact plate 95 is sandwiched between them, and a pair of outer surfaces of the upper screw cylinder 83 and the lower screw cylinder 88 can be brought into contact with the end face 56 to be hermetically sealed. The closing plate 93
Is pulled by a spring 100, and an upper taper portion 97 and a lower taper portion 98 that match the upper taper surface 86 and the lower taper surface 90 are provided inside the closing plate 93, and a valve using a hot tap fitting is provided. did.

[0027]

The valve using the hot tap fitting of the present invention is installed without stopping the flow in the pipe 5 as described below.

That is, the fitting 1 is attached to the outer circumference of the pipe 5.
(FIG. 18) is mounted as shown in FIG. 1, a conventionally known gate valve 7 (FIG. 12) is mounted on the flange 2a of the fitting 1, and the conventionally known punching machine 8 (FIG. 20) is attached to the gate valve 7. ) Is attached, the gate valve 7 is opened, and the cutting portion 55 is provided in the pipe 5 with the cylindrical cutter 9.

Next, the cut portion of the cutter 9 and the pipe 5 is pulled up into the punching machine 8 and the gate valve 7 is closed.
The punch 8 is removed from the gate valve 7. Next, as shown in FIG. 1, the upper screw cylinder 83 shown in FIG. 6 is screwed into the upper male screw 80 of the central shaft 75 shown in FIG.
A lower screw cylinder 88 is screw-fitted into the upper screw cylinder 83 and the lower screw cylinder 88, and a pair of closing plates 93 is placed outside the upper screw cylinder 83 and the lower screw cylinder 88. The upper tapered surface 86 of the screw cylinder 83 and the lower screw cylinder 8
The lower plate 93 is brought into contact with the lower tapered surface 90, and the closing plate 93 is pulled by the spring 100 to be mounted.

Next, as shown in FIG. 2, the central shaft 75 is rotatably tightly fitted into the shaft insertion hole 66 of the sealing plug 65, and is mounted so as to hang down from the sealing plug 65. The rod 70 is inserted into the vertical holes 87 of the upper screw cylinder 83 and the lower screw cylinder 88 to connect the upper screw cylinder 83 and the lower screw cylinder 88 to the sealing plug 6.
5 is mounted so that it can slide up and down and cannot rotate.

Next, the central shaft 75 is screwed to the shaft 39 of the plug tightening machine 38 shown in FIG.
8 is attached to the gate valve 7 in the closed state.
Then, the gate valve 7 is opened, the shaft 39 is lowered, the closing plate 93 is inserted into the cutting portion 55 of the pipe 5, and the sealing plug 65 is fixed to the fitting 1 with the set screw 61 as shown in FIG. Then, the opening is sealed.

Next, the shaft 39 is unscrewed from the central shaft 75,
The plug tightener 38 and the gate valve 7 are removed from the fitting 1. Then, without stopping the flow of the pipe 5,
Cut the tube 5 and install the valve as shown in FIG.

In order to stop the flow in the pipe 5, the central shaft 75 is rotated in a certain direction, and the upper screw cylinder 83 and the lower screw cylinder 88 come close to each other, and the upper tapered surface 86 and the lower tapered surface 86. 90 pushes the closing plate 93 against the spring 100, which closes the end face 56 of the tube 5.

To re-flow the flow in the pipe 5, the central shaft 75
Is rotated in the opposite direction to the above, each part moves in the opposite direction to the above, the closing plate 93 is separated from the end surface 56 of the pipe 5, and the fluid flows.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A valve using a hot tap fitting according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 16. The construction method and the like are the same as those of the conventional example described above. Description will be made with reference to the drawings of the above-mentioned conventional example, with some omitted.

The valve using the hot tap fitting of this embodiment does not stop the flow in the existing pipe 5,
The fitting 1 is attached to the pipe 5, the cut portion 55 is formed in the pipe 5 in the fitting 1, and the valve is attached.

The fitting 1 is shown in FIGS.
As shown in FIG. 19 and the like, the upper fitting 2 and the lower fitting 3 are welded and attached to the outer periphery of the pipe 5 by fillet welding 20, and are also welded and connected by butt welding 21 to the upper portion of the upper fitting 2. Are provided by connecting the neck fittings 17 by welding 23.

As shown in FIG. 1, an annular step 58 is provided in the opening of the neck fitting 17, and an annular groove 59 is formed on the upper surface of the step 58. The O-ring 25 is fitted in the annular groove 59.

As shown in FIG. 1, the neck fitting 17 has an annular step 58 from the outer periphery thereof.
A large number of setscrew insertion holes 60 drilled on the upper side of the set screws are provided at equal intervals. A recessed groove is formed in the set screw insertion holes 60 and a small O-ring is fitted therein. A set screw 61 having a conical tip portion 62 is screwed into 60.

The pipe 5 in the fitting 1 is shown in FIG.
A cutting portion 55 cut by a cylindrical cutter 9 as shown in 0 is provided, and this cutting portion 55 is seen from the upper surface,
It is formed on the arc-shaped end surface 56.

Then, as shown in FIG. 1, the sealing plug 65 fitted in the opening of the neck fitting 17 is
It is formed in a disc shape, and as shown in FIG. 4, a concave groove 68 is provided in the upper part of the peripheral edge of the sealing plug 65.
A triangular groove 69 is provided below the concave groove 68.

As shown in FIG. 1, the sealing plug 65 is provided with a shaft insertion hole 66 in the center thereof, and a recess groove is formed in the insertion hole 66. A small O-ring is fitted in.

A pair of recesses 67 are provided on the upper surface of the sealing plug 65, and a pair of rods 70 are hung and welded on the lower surface of the sealing plug 65. Then, as shown in FIG. 1, the sealing plug 65 is placed on the step 58 of the neck fitting 17 via the O-ring 25, and is pressed against the O-ring 25 by the set screw 61. Fixed.

Further, the annular fixing member 103 is screwed into the female screw 18 provided in the opening of the neck fitting 17, and the sealing stopper 65 is pressed against the O-ring 25 also by the annular fixing member 103. It is formed on.

In the shaft insertion hole 66 of the sealing plug 65,
A central shaft 75 shown in FIG. 5 is rotatably fitted tightly. As shown in FIG. 1, the central shaft 75 is prevented from coming out upward by a collar 79, and is made to come out downward by using a shaft fixing screw 77. It is prevented by a shaft fixing nut 78 that is screwed in, and the central shaft 75 can be fixed by strongly tightening the shaft fixing nut 78.

The collar 79 includes an upper screw cylinder 83 and a lower screw cylinder 8.
8 is screwed to the central shaft 75 and then welded and fixed to be assembled. In addition, in the upper part of the central shaft 75,
A connecting screw 76 is provided, and in the middle position, an upper male screw 80 formed as a right-hand screw is provided.
A lower male screw 81 formed as a left screw is provided on the lower portion of the No. 5.

As shown in FIGS. 6 and 7, the right-handed upper male screw 80 provided on the central shaft 75 has a right-handed upper screw cylinder 83 whose upper portion is formed as a large-diameter conical column. The upper female screw 84 is screwed.

In addition, the lower male screw 81 of the left-hand screw is shown in FIG.
As shown in FIG. 5, the lower female thread 89 of the lower thread of the lower threaded barrel 88, the lower part of which is formed of a large diameter conical column, is screwed. The upper screw cylinder 83 and the lower screw cylinder 88 are respectively provided with
As shown in FIG. 2, a pair of vertical holes 87 are provided, and the vertical holes 87 are slidably fitted onto a rod 70 provided so as to hang down from the sealing plug 65, and the upper screw cylinder 83 is provided. ,as well as,
The lower screw cylinder 88 is formed so as not to rotate together with the central shaft 75.

Two flat plates 85 are provided in parallel on both sides of the upper screw cylinder 83 (FIGS. 6 and 7), and an upper taper surface 86 is provided between the flat plates 85. The upper tapered surface 86 is provided so as to be inclined so that the lower portion approaches the center.

As shown in FIG. 1, the lower screw cylinder 88 is also provided with a flat plate 85 similar to the upper screw cylinder 83. Between the flat plates 85, the upper taper surface 86 and the direction of inclination are provided. A lower tapered surface 90 is provided which is opposite to the above.

Outside the upper screw cylinder 83 and the lower screw cylinder 88, there are provided a pair of closing plates 93 formed as arc-shaped curved plates shown in FIG. is there. (FIG. 8) Then, a rubber elastic plate 94 having a larger diameter than the outer diameter of the pipe 5 is attached to the surface of the closing plate 93, and the inside of the closing plate 93 is
A contact plate 95 is provided in the vertical direction.

The upper and lower parts of the contact plate 93 are
An upper taper portion 97 that matches the upper taper surface 86 of the upper screw cylinder 83 and a lower taper portion 98 that matches the lower taper surface 90 of the lower screw cylinder 88 are provided.

Then, the contact plate 93 is replaced with the flat plate 85.
1 and a spring 100 is stretched between the hooks 99 provided inside the closing plate 93, as shown in FIG.
Pulling the pair of closing plates 93 inward, the upper taper portion 9
7 and the lower taper portion 98 are attached to the upper taper surface 86 and the lower taper surface 90 in contact with each other.

Then, the bottom plate 71 shown in FIGS. 9 and 10 is applied to the lower side of the lower screw cylinder 88 and the closing plate 93 to attach the bottom plate 7 to the bottom plate 71.
The rod 70 is inserted into the hole 72 of No. 1 and a nut is screwed onto the tip of the rod 70 to be mounted.

Then, the closing plate 93 is pulled by the spring 100, and the upper taper part 97 and the lower taper part 9 are pulled.
In FIG. 8, since it is in contact with the upper screw cylinder 83 and the lower screw cylinder 88, it does not fall even without the bottom plate 71.

Further, the upper screw cylinder 83 and the lower screw cylinder 88.
Is formed into a cylindrical shape or the like, and a groove is formed into the cylindrical shape or the like, and the bottom surface of the groove is formed into an upper tapered surface 86 and a lower tapered surface 9
It is also possible to form 0.

The valve using the hot tap fitting of this embodiment is attached to the pipe 5 without stopping the flow of the pipe 5 as described below. That is, a fitting 1 consisting of a neck fitting 17, an upper fitting 2, and a lower fitting 3 on the outer circumference of the pipe 5.
(FIGS. 1 and 9) are mounted, and a conventionally known gate valve 7 is mounted on the flange 2a of the neck fitting 1.
(FIG. 12) is attached, and a conventionally known punching machine 8 (FIG. 20) is attached to the gate valve 7.

Next, the gate valve 7 is opened, and the pipe 5 is provided with the cutting portion 55 by the cylindrical cutter 9. Then, the cut portion of the cutter 9 and the pipe 5 is pulled up into the punching machine 8, the gate valve 7 is closed, and the punching machine 8 is closed.
Remove from.

Next, the upper male screw 80 of the central shaft 75 shown in FIG. 5 is screwed with the upper screw barrel 83 shown in FIGS. 1 and 6, and the lower male screw 81 is screwed with the lower screw barrel 88. Screw cylinder 83
A pair of closing plates 93 (FIG. 8) are placed on the outside of the lower screw cylinder 88 and the upper tapered portion 97 and the lower tapered portion 98 of the closing plate 93, respectively.
6 and the lower tapered surface 90 of the lower screw cylinder 88.

Then, the spring 100 shown in FIG. 1 is stretched between the hooks 99 provided on the closing plate 93, and the closing plate 93 is pulled inward and mounted. Next, the central shaft 75 is rotatably tightly fitted into the shaft insertion hole 66 of the sealing plug 65 shown in FIGS. 1 and 2, and the shaft fixing screw 77 of the central shaft 75 is attached to the shaft fixing nut 78. It is fitted by screwing and is attached, and the sealing plug 65
The pair of rods 70 hung down is inserted into the vertical holes 87 of the upper screw cylinder 83 and the lower screw cylinder 88, and the bottom plate 71 shown in FIGS. 9 and 10 is provided below the closing plate 93. Pad, bottom plate 71
The rod 70 is inserted through the hole 72, and a nut is screwed onto the tip of the rod 70 to be mounted.

Next, the central shaft 75 is screwed onto the shaft 39 of the plug tightening machine 38 shown in FIG.
8 is attached to the gate valve 7 in the closed state.
Then, the gate valve 7 is opened, the shaft 39 is lowered, the closing plate 93 is advanced into the cut portion 55 of the pipe 5, the sealing plug 65 is fixed to the neck fitting 17 with the set screw 61, and the O-ring. Press contact with 25.

Next, the shaft 39 is unscrewed from the central shaft 75,
The plug clamp 38 and the gate valve 7 are removed from the neck fitting 17 (FIG. 13), the pipe 5 is cut without stopping the flow of the pipe 5, and the valve is mounted as shown in FIG.

Then, the annular fixing member 108 is screwed into the female screw 18 of the neck fitting 17. To stop the flow in the tube 5, as shown in FIG. 14, the operation rod 104 is connected to the central shaft 75, the shaft fixing nut 78 is loosened slightly, and then the central shaft 75 is rotated counterclockwise.

Then, the upper screw cylinder 83 moves downward and the lower screw cylinder 88 moves upward. Then, according to the upper tapered surface 86 of the upper screw cylinder 83 and the lower tapered surface 90 of the lower screw cylinder 88, the closing plate 93 is pushed out against the spring 100, and the elastic plate 94 is pressed against the end surface 56 of the pipe 5. Close.

To re-flow the flow in the tube 5, the central shaft 75
When is rotated to the right, each part moves in the opposite direction to the above, and the closing plate 9
3 is attracted by the spring 100, the end surface 56 of the tube 5 is opened, and the fluid flows.

In order to prevent the flow rate from being obstructed by the closing plate 93, the direction of the closing plate 93 should be made parallel to the pipe axis direction, and all the set screws 61 should be slightly retracted, and then the annular shape should be changed. The fixture 103 is loosened slightly, and the sealing plug 65 is rotated 90 degrees using the sealing plug operating rod 105 shown in FIG. Then, as shown in FIG. 16, the closing plate 93 also rotates 90 degrees from the end surface 56 of the tube 5, and the void 106 is located in front of the end surface 56 of the tube 5.
The area through which the fluid passes increases.

[0067]

In the valve using the hot tap fitting of the present invention, the central shaft 75 is rotatably tightly fitted in the sealing plug 65, and the central shaft 75 is rotated to
The closing plate 93 that comes into contact with the end surface 56 of the pipe 5 is formed so as to be able to move forward and backward.

The valve of the present invention can be attached to the fitting 1 used for cutting the pipe 5 without stopping the flow of the pipe 5. Therefore, the amount of work for inserting the valve into the pipe 5 is reduced, and the work period can be shortened.

Further, since a device that greatly restricts the flow rate such as a bypass circuit is not used, the flow rate does not drop during the construction, and the construction can be performed at a time when the consumption of the fluid flowing in the pipe 5 is large. The valve can be inserted into the pipe 5 without restriction on the construction time.

Furthermore, since the closing plate 93 is advanced and retracted to the end face 56 of the pipe 5 and abuts against it, the closing plate 93 can be strongly pressed against the end face and the flow can be completely closed.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a front view of a sealing plug according to an embodiment of the present invention.

FIG. 5 is a perspective view of a central shaft according to an embodiment of the present invention.

FIG. 6 is a perspective view of an upper screw cylinder according to an embodiment of the present invention.

FIG. 7 is a side view of the upper screw cylinder according to the embodiment of the present invention.

FIG. 8 is a perspective view of a closing plate according to an embodiment of the present invention.

FIG. 9 is a sectional view of a bottom plate according to an embodiment of the present invention.

FIG. 10 is a perspective view of a bottom plate according to an embodiment of the present invention.

FIG. 11 is a perspective view of an annular fixing tool according to an embodiment of the present invention.

FIG. 12 is a diagram showing a mounting state according to an embodiment of the present invention.

FIG. 13 is a diagram showing a mounting situation according to an embodiment of the present invention.

FIG. 14 is a diagram showing an operation status of one embodiment of the present invention.

FIG. 15 is a diagram showing an operation status of one embodiment of the present invention.

FIG. 16 is a diagram showing an operation status of one embodiment of the present invention.

FIG. 17 is a view showing a state where fittings of a conventional example are attached at two places.

FIG. 18 is an exploded perspective view of a conventional fitting.

FIG. 19 is a view showing a state in which a fitting of a conventional example is attached to a pipe.

FIG. 20 is a diagram showing a state in which a conventional pipe is about to be cut.

FIG. 21 is a view showing a mounting state of a stopper of a conventional example.

FIG. 22 is a view showing a state in which a bypass circuit is provided in the conventional tube.

FIG. 23 is a perspective view of a main part of a conventional stopper.

FIG. 24 is a view showing a state in which a stopper is attached to a conventional pipe.

FIG. 25 is a view showing a state where a valve is inserted in a pipe of a conventional example.

FIG. 26 is a view showing a conventional plug tightener and a seal stopper.

FIG. 27 is a perspective view of a conventional seal plug.

FIG. 28 is a perspective view showing a back surface and a front surface of a conventional screw tightening fork.

FIG. 29 is a view showing a main part of a shaft of a conventional plug fastening machine and a main part of the shaft and a screw fastening fork.

FIG. 30 is a diagram showing an engaged state of a conventional screw tightening fork.

FIG. 31 is a view showing an essential part of a fitting of a conventional example closed with a seal plug.

FIG. 32 is a view showing a detached state of a conventional screw tightening fork.

FIG. 33 is a view showing a state where insertion of a valve into a pipe of a conventional example is completed.

[Explanation of symbols]

 1 Fitting 5 Pipe 55 Cut Part 56 End Face 58 Step 61 Set Screw 65 Sealing Plug 66 Shaft Insertion Hole 70 Rod 75 Center Shaft 76 Connecting Screw 80 Upper Male Thread 81 Lower Male Thread 83 Upper Screw Cylinder 86 Upper Tapered Surface 87 Vertical Hole 88 Lower screw cylinder 90 Lower taper surface 93 Closing plate 97 Upper taper portion 98 Lower taper portion 100 Spring

Front Page Continuation (72) Inventor Tomiyuki Kito, 1-2 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Inventor, Youji Takanashi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Steel Pipe Co., Ltd. (72) Inventor Kazutaka Akao 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Japan Steel Tube Co., Ltd.

Claims (1)

[Claims] 1. A fitting 1 is attached to the outer circumference of a pipe 5, and a cutting portion 55 is provided on the pipe 5 in the fitting 1,
A sealing plug 65 having a shaft insertion hole 66 is fitted on a step portion 58 that forms the end face 56 and is provided in the opening of the fitting 1. The sealing plug 65 is a plurality of screws fitted from the outer periphery of the fitting 1. The set shaft 61 is fixed by a set screw 61 to seal the opening, and a central shaft 75 provided with a connecting screw 76 is rotatably tightly fitted and mounted in the shaft insertion hole 66.
Is provided with an upper male screw 80, and a lower male screw 81 inclined in the opposite direction to the upper male screw 80 is provided below the upper male screw 80. The upper male screw 80 and the lower male screw 81 are provided with a vertical hole 87. The cylinder 83 and the lower screw cylinder 88 are screw-fitted, and the vertical hole 87 is externally fitted to the rod 70 hung from the sealing plug 65 so as to be vertically slidable, and the upper screw cylinder 83 and the lower screw cylinder 88 are attached. Is provided with an upper taper surface 86 and a lower taper surface 90 whose inclination directions are opposite to each other, and on the outside of the upper screw cylinder 83 and the lower screw cylinder 88, a pair of closing plates capable of contacting and sealing the end surface 56. 93 is pulled by a spring 100, and the upper tapered surface 86 is provided inside the closing plate 93.
And a valve using a hot tap fitting provided with an upper tapered portion 97 and a lower tapered portion 98 that match the lower tapered surface 90.