JP3706889B2 - Wellhead seal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wellhead packing device installed at a wellhead, and more particularly, to an inner peripheral surface of a wellhead, a tunnel segment, a buried pipe, and the like disposed in an excavation shaft that is communicated with the wellhead and formed in the ground. The present invention relates to a wellhead packing device that seals between an outer peripheral surface of a pipe formation body.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, another excavation mine, such as a tunnel pit or a shaft pit, is constructed in the ground by a shield method or a propulsion method from a pit such as a pit or a tunnel pit, or a pit provided on the surface of the earth. In the shield method, pipes are formed in the excavated mine by sequentially performing an operation of assembling the segments into a tubular shape or a partially opened peripheral frame at the rear part of the excavator for excavating the ground. Also, in the propulsion method, the back end of the buried pipe connected to the rear part of the excavator or the blade tube is pressed with the propulsion machine, and the ground is pushed by the excavator or the hand excavator while being pressed into the ground. By excavating, a pipeline is formed in the excavated mine.
[0003]
Therefore, in both the shield method and the propulsion method, there is a gap between the starting or reaching wellhead and the outer peripheral surface of the excavator, and between the wellhead and the outer peripheral surface of the segment or the buried pipe. It is necessary to seal and prevent inflow of earth and sand, groundwater, etc. into the start mine and the arrival mine.
[0004]
A conventional wellhead sealing device is, for example, as shown in Japanese Patent Laid-Open No. 48-76347, in which a tubular packing is attached to the inner peripheral surface of a wellhead, and fluid is pressed into the tubular packing from the inlet. Thus, the tubular packing is expanded so as to be brought into pressure contact with the outer peripheral surface of the pipe forming body and the outer peripheral surface of the leading device in the excavator at the tip thereof.
[0005]
[Problems to be solved by the invention]
In the conventional wellhead sealing device described above, in order to expand the tubular packing, it is necessary to press-fit the fluid into the tubular packing by using a fluid supply device or a dedicated pipe. Further, since the pressure tightness of the tube packing itself is required, it is necessary to keep the strength and quality of the tube packing high, and there is a disadvantage that the material cost and the manufacturing cost are high. In addition, when a crack or the like is generated in the tubular packing due to external damage or the like, there is a disadvantage that the internal fluid flows out and does not function as the packing.
[0006]
Accordingly, an object of the present invention is to provide a wellhead seal device that has a simple structure, is easy to store, transport and install, and is excellent in waterstop.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention is a wellhead seal device for pressure-tightly sealing between a wellhead of a borehole and a conduit forming body disposed in the borehole, An elastic packing having a portion attached to the wellhead and having an opening smaller than the outer shape of the pipe-forming body, and absorbing and expanding water inside the excavation hole from the surface, whereby the pressure receiving surface of the elastic packing And a water-absorbing / expanding member that presses the peripheral edge of the opening against the outer peripheral surface of the duct-forming body from the side.
[0008]
In the wellhead sealing device having the above-described configuration, when the elastic packing liquid-tightly seals between the wellhead of the excavation hole and the outer peripheral surface of the pipe formation body, the water absorbing expansion member absorbs the water filled in the excavation hole and absorbs the wellhead. By expanding the volume between the inner peripheral surface and the pipe forming body, the peripheral edge of the opening can be strongly pressed against the outer peripheral surface of the pipe forming body from the pressure receiving surface side of the elastic packing. An excellent wellhead seal device can be provided. Moreover, since the water absorption expansion member can absorb the water inside the excavation hole from its surface and expand in volume, even if there is no water supply device or dedicated supply pipe for expanding the water absorption expansion member Alternatively, even if they are present, the water-absorbing expansion member can be rapidly expanded without using them. Furthermore, since the water-absorbing expansion member expands in volume due to water absorption from its surface, the expansion characteristics are not impaired even if a crack or the like occurs on the surface of the water-absorption expansion member due to external damage or the like. Accordingly, it is possible to provide a pressure-resistant wellhead sealing device that has a simple configuration and high reliability.
[0009]
In the wellhead sealing device having the above-described configuration, the water absorbing and expanding member may be attached to the wellhead so as to be in contact with the pressure receiving surface of the elastic packing, or may be attached to the pressure receiving surface side of the elastic packing.
[0010]
Further, the present invention is a wellhead sealing device for pressure-tightly sealing between a wellhead of a borehole and a pipe formation body disposed in the borehole, the outer periphery of the pipe formation body A water absorbing expansion member having an outer peripheral portion attached to the wellhead so as to surround the entire circumference, and the water absorbing expansion member absorbs water in the excavation hole from its surface and expands its volume, thereby There is provided a wellhead sealing device characterized in that a liquid-tight seal is provided between a surface and an outer peripheral surface of the pipe line forming body.
[0011]
In the wellhead sealing device having the above structure, the water absorption and expansion member attached to the wellhead of the excavation hole absorbs the water filled in the excavation hole and is volume-expanded between the inner periphery of the wellhead and the pipe formation body, Since the space between the inner peripheral surface of the wellhead and the outer peripheral surface of the pipe line forming body can be liquid-tightly sealed, a wellhead seal device having excellent pressure-proof water resistance can be provided. Moreover, since the water absorbing expansion member can absorb the water in the excavation hole from the surface and expand the volume, even if there is no water supply device or dedicated supply piping for expanding the water absorption expansion member, Alternatively, even if they are present, the water-absorbing expansion member can be rapidly expanded without using them. Furthermore, since the water-absorbing expansion member expands in volume due to water absorption from its surface, the expansion characteristics are not impaired even if a crack or the like occurs on the surface of the water-absorption expansion member due to external damage or the like. Accordingly, it is possible to provide a pressure-resistant wellhead sealing device that has a simple configuration and high reliability.
[0012]
In the wellhead sealing device of the present invention described above, preferably, the water absorbing / expanding member includes a water-permeable bag and a water-absorbing polymer accommodated in the bag.
[0013]
In the wellhead sealing device having such a configuration, since the water absorbing polymer is used as the water absorbing material, the water absorbing expansion member is light and compact when not absorbing water, and storage, transportation, attachment, and the like are facilitated. In addition, the water-absorbing polymer has a high water absorption speed and can expand 5 to 10 times the volume due to water absorption. Therefore, by using this water-absorbing polymer, the space between the inner peripheral surface of the wellhead and the pipe formation body can be quickly and effectively used. It becomes possible to seal liquid tightly.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0015]
【Example】
FIGS. 1 to 3 show a first embodiment in the case where the wellhead sealing device according to the present invention is applied to a wellhead of a start side shaft of a propulsion method. FIG. 1 is a schematic longitudinal sectional side view showing a state in which a wellhead sealing device is attached to a wellhead before starting excavation, and FIG. 2 is a schematic end view of the wellhead sealing device shown in FIG. 3 is a schematic end view of the wellhead sealing device shown in FIG. 1 as viewed from the excavation hole side, and FIG. 4 is an enlarged vertical sectional view of the main part of the wellhead sealing device shown in FIG. (B) is sectional drawing similar to FIG. 4 which respectively shows the use condition of the wellhead sealing apparatus shown in FIG.
[0016]
Referring to these drawings, a tubular body 3 that forms a pit for forming a digging pit 4 having a substantially circular cross section is formed on the pit wall 2 of the pit 1 so as to project inward of the pit 1. The wellhead seal device 5 according to the present invention is attached to the end of the cylindrical body 3. An excavation machine 7 as a leading device is attached to the tip of the buried pipe 6 as a duct forming body pushed out by a propulsion device (not shown), and the excavation machine 7 opens the excavation pit 4 and embeds it behind it. The pipes 6 are sequentially added to enter the excavation pit 4.
[0017]
The wellhead seal device 5 has an external pressure between the tubular body (wellhead) 3 and the outer peripheral surface of the excavator 7 and between the tubular body 3 and the outer peripheral surface of the buried pipe 6 in accordance with the entry of the excavator 7 and the buried pipe 6. (Pressure, water pressure, earth pressure, etc. inside the excavation pit 4) are sequentially sealed to withstand pressure, a plate-like elastic packing 8, a backing member 9, and the water absorption expansion that characterizes the present invention. Member 10.
[0018]
The elastic packing 8 is preferably made mainly of rubber, and its outer peripheral part 8a is attached to the end face part of the cylindrical body 3, and has an opening 8b smaller than the outer shape of the buried pipe 6 at the center part. Yes. The opening 8b of the elastic packing 8 can be expanded and deformed by the excavator 7 and the buried pipe 6 as shown in FIGS. 5A and 5B when the excavator 7 and the buried pipe 6 enter.
[0019]
The backing member 9 is made of an elastic metal plate, and the outer peripheral portion 9 a is attached to the end surface portion of the cylindrical body 3. The backing member 9 has an opening 9b that is smaller than the outer shape of the buried pipe 6 and larger than the opening of the elastic packing 8, and the inner peripheral side of the backing member 9 is formed in a strip shape. As can be seen from FIGS. 5A and 5B, when the elastic packing 8 seals the outer peripheral surface of the excavator 7 or the buried pipe 6, the inner peripheral portion of the backing member 9 is on the inner side of the excavation pit 4. Since the inner peripheral end of the bending machine 7 or the buried pipe 6 is in contact with the outer peripheral surface of the excavating machine 7 in the state of being bent and deformed, the back surface side of the elastic packing 8 can be supported by pressure against the external pressure acting on the elastic packing 8. .
[0020]
As shown in FIGS. 3 to 5, the water-absorbing / expanding member 10 of the first embodiment absorbs the water inside the excavation hole 4 from its surface and expands, so that the opening periphery of the elastic packing 8 from the pressure-receiving surface side. The part can be pressed against the outer peripheral surfaces of the excavating machine 7 and the buried pipe 6.
[0021]
More specifically, the water absorbent expansion member 10 includes a bag body 11 having water permeability and a water absorbent polymer 12 accommodated in the bag body 11. As shown in FIG. 3, the bag body 11 of this embodiment is formed in a substantially arc shape along the inner periphery of the cylindrical body 3, and the outer peripheral side is inside the top inner peripheral surface and the bottom of the cylindrical body 3. Attached to the peripheral surface. The water-absorbing expansion member 10 provided on the top side of the cylindrical body 3 is formed when the excavator 7 or the buried pipe 6 is displaced below the center of the cylindrical body 3 due to its own weight or the like. A gap between the inner peripheral surface and the outer surface of the excavator 7 or the buried pipe 6 can be prevented from expanding and the sealing performance by the elastic packing 8 from being deteriorated. Moreover, the water absorption expansion | swelling member 10 provided in the bottom part side of the cylindrical body 3 can play the role which prevents that the sealing performance falls because the elastic packing 8 itself sags with its own weight. .
[0022]
Although detailed illustration is omitted, the bag body 11 is preferably composed of an outer bag and an inner bag, and the outer bag is preferably made of a material having a high resistance to trauma and impact, and the inner bag preferably has a polymer. Consists of materials that are rich in nature. It is desirable that both the outer bag and the inner bag have good water permeability so that the water-absorbing expansion member 10 can absorb water from its surface. Moreover, it is desirable that both the outer bag and the inner bag have good stretchability so that they can expand according to the volume expansion of the water-absorbing polymer 12. As these bag materials, polyester-based nonwoven fabrics or mesh fabrics formed by knitting fibers so as to be stretchable are preferable.
[0023]
The water-absorbing polymer 12 can be used in the form of a sheet formed in a multilayer form. In this case, it is effective if it is accommodated in the bag body 11 so that the laminating direction substantially coincides with the radial direction between the inner peripheral surface of the wellhead 3 and the pipe formation body (the excavator 7 and the buried pipe 6). It can be swollen with water.
[0024]
In the horizontal well seal apparatus, the water absorbing and expanding member 10 attached to the tubular body 3 forming the well opening of the excavation hole 4 absorbs water in the excavation hole 4 and the inner peripheral surface of the tubular body 3 and the pipe line. By performing volume expansion between the forming machine 7 or the buried pipe 6 as a forming body, the space between the inner peripheral surface of the tubular body 3 and the outer peripheral surface of the working machine 7 or the buried pipe 6 is liquid-tightly sealed. Can do. Moreover, the water-absorbing expansion member 10 absorbs the water in the excavation hole 4 and expands, and it is not necessary to separately provide a supply device or supply pipe for supplying expansion water or the like, so the configuration is simple. It is possible to provide a pressure-resistant wellhead seal device that can be easily installed. The water filled in the excavation hole 4 is composed of ground water contained in the ground or water supplied from the excavator 7 or the like toward the excavation unit in order to make the excavation unit muddy during excavation.
[0025]
As shown in FIG. 5, when the excavator 7 is located inside the cylindrical body 3, the water absorbing expansion member 10 is in the inner peripheral portion of the elastic packing 8 that is in close contact with the outer peripheral surface of the excavator 7 due to water absorption expansion. A gap between the side and the inner peripheral surface of the cylindrical body 3 can be filled (see FIG. 5A). Further, when the buried pipe 6 is positioned inside the cylindrical body 3, the water absorbing / expanding member 10 further absorbs and expands, whereby the inner peripheral side of the elastic packing 8 that is in close contact with the outer peripheral surface of the buried pipe 6 and A gap between the inner peripheral surface of the cylindrical body 3 can be filled (see FIG. 5A). Therefore, a pressure-resistant seal structure with excellent adaptability can be obtained.
[0026]
In the first embodiment, the backing member 9 is used and the backing member 9 is made of a metal plate having a spring property. A movable plate (oscillating plate) type attached via a hinge as shown in 2-213587 may be used. Further, the backing member 9 may be omitted.
[0027]
6 and 7 show a second embodiment of the present invention. 6 is a longitudinal sectional view of the main part of the wellhead sealing device, and FIG. 7 is an end view of the wellhead sealing device shown in FIG. In these drawings, the same reference numerals are given to the same components as those in the above embodiment.
[0028]
In the second embodiment shown in FIG. 6 and FIG. 7, the cylindrical body 3 that forms the pit of the excavation hole 4 and the excavator 7 or the buried pipe 6 as a pipe line forming body disposed in the excavation hole 4. The wellhead seal device for pressure-tightly sealing the space includes a water absorbing and expanding member 10 having an outer peripheral portion attached to the tubular body 3 so as to surround the outer periphery of the excavator 7 or the buried pipe 6 over the entire circumference. Yes.
[0029]
This water-absorbing expansion member 10 seals the gap between the inner peripheral surface of the tubular body 3 and the excavator 7 when the excavator 7 is positioned inside the tubular body 3, but fills the excavation hole 4. By rapidly absorbing the water to be absorbed from the surface of the water absorbing and expanding member 10 and expanding the volume, the gap between the inner peripheral surface of the cylindrical body 3 and the excavator 7 can be sealed with a stronger force. When the buried pipe 6 is positioned inside the cylindrical body 3, the water absorbing / expanding member 10 further rapidly absorbs the water in the excavation hole 4 and volume expands, so that the inner peripheral surface of the cylindrical body 3 A space between the outer peripheral surface of the buried pipe 6 can be sealed with a strong force.
[0030]
Although the illustrated embodiment has been described above, the present invention is not limited only to the embodiment described above, and various modifications can be made to the components within the scope of the invention described in the claims. it can. For example, the backing member 9 in the first embodiment may be omitted. Moreover, although the water absorption expansion member 10 in 1st Example is attached to the internal peripheral surface of the cylindrical body 3 which makes a wellhead, you may provide integrally with this elastic packing 8 in the pressure receiving surface side of the elastic packing 8. FIG.
[0031]
Furthermore, the present invention applies not only to the start hole of the shaft, but also to the access port, the tunnel for forming a branch tunnel formed on the tunnel wall, or the port provided on the ground surface for the construction of the shaft. Can be applied. In addition, the elastic packing can be formed into a rectangular shape, a horseshoe shape, a gourd shape, a gate shape, or the like in accordance with the shape of the applied duct forming body. In that case, in the configuration aspect of the first embodiment, the water-absorbing expansion member is disposed at a location where the pressing force of the elastic packing itself against the pipe forming body is lowered, for example, a straight portion or a constricted portion, thereby enhancing the sealing performance. be able to. Furthermore, when the present invention is applied to a wellhead used in the propulsion method, it can ensure a good sealing property on the outer peripheral surface of the blade tube and the fume tube as a pipe formation body, and the shield method When applied to the wellhead used, good sealing performance can be ensured on the outer periphery of the shield machine main body and the outer peripheral surface of the segment as a pipe formation body.
[0032]
【The invention's effect】
As is clear from the above description, the present invention is a wellhead seal device for pressure-tightly sealing between a wellhead of a borehole and a conduit forming body disposed in the borehole, An elastic packing having an outer peripheral part attached to the wellhead and having an opening smaller than the outer shape of the pipe line forming body, and absorbing the water inside the excavation hole from the surface to expand the volume of the elastic packing. A water-absorbing and expanding member that presses the peripheral edge of the opening from the pressure-receiving surface side to the outer peripheral surface of the pipe-forming body, so that the pipe-forming body is sealed by the elastic packing at the time of sealing by the elastic packing. The force can be strengthened by the water absorbing expansion member. Therefore, it is possible to ensure a good pressure-proof sealing property regardless of the cross-sectional shape of the pipe line forming body. In addition, since the water-absorbing expansion member can absorb the water in the excavation hole from the surface and expand the volume, the volume expansion function is not impaired even if a crack or the like occurs on the surface due to an injury or the like. Therefore, it is possible to provide a pressure-resistant wellhead sealing device that has a simple configuration and high reliability.
[0033]
Further, the present invention is a wellhead sealing device for pressure-tightly sealing between a wellhead of a borehole and a pipe formation body disposed in the borehole, the outer periphery of the pipe formation body A water absorbing expansion member having an outer peripheral portion attached to the wellhead so as to surround the entire circumference, and the water absorbing expansion member absorbs water in the excavation hole from its surface and expands its volume, thereby Since it seals between a surface and the outer peripheral surface of the said pipe line formation body liquid-tightly, the wellhead sealing apparatus excellent in the pressure-proof water stop property can be provided. In addition, since the water-absorbing expansion member can absorb the water in the excavation premises from the surface and expand the volume, the volume expansion function is not impaired even if a crack or the like occurs on the surface due to an external damage or the like. Accordingly, it is possible to provide a pressure-resistant wellhead sealing device that has a simple configuration and high reliability.
[Brief description of the drawings]
FIG. 1 shows a first embodiment in which a wellhead seal device according to the present invention is applied to a wellhead of a start side shaft of a propulsion method, and a state where a wellhead seal device is attached to a wellhead of a shaft before starting excavation It is a schematic longitudinal cross-sectional side view which shows this.
FIG. 2 is a schematic end view of the wellhead sealing device shown in FIG. 1 as viewed from the inside of the shaft.
FIG. 3 is a schematic end view of the wellhead sealing device shown in FIG. 1 as viewed from the excavation hole side.
4 is an enlarged vertical cross-sectional view of a main part of the wellhead seal apparatus shown in FIG. 1. FIG.
FIGS. 5A and 5B are cross-sectional views similar to FIG. 4 showing a use state of the wellhead seal apparatus shown in FIG.
FIG. 6 is a longitudinal sectional view of an essential part of a wellhead seal device showing a second embodiment of the present invention.
7 is an end view of the wellhead sealing apparatus shown in FIG. 6 as viewed from the excavation hole side.
[Explanation of symbols]
1 Shaft 2 Bore 3 Tubular body (wellhead)
4 Drilling hole 5 Wellhead seal device 6 Buried pipe (pipe formation body)
7 digging machine (pipe formation body)
8 Elastic packing 9 Backing member 10 Water-absorbing expansion member 11 Bag body 12 Water-absorbing polymer

Claims (3)

A wellhead seal device for pressure-tightly sealing between a wellhead of a borehole and a pipe formation body disposed in the borehole, wherein an outer peripheral portion is attached to the wellhead and the pipe An elastic packing having an opening smaller than the outer shape of the path forming body and volume expansion by absorbing water inside the excavation hole from the surface, thereby forming the pipe peripheral edge from the pressure receiving surface side of the elastic packing. A wellhead sealing device comprising: a water-absorbing expansion member that is pressed against the outer peripheral surface of the body. A wellhead sealing device for pressure-tightly sealing between a wellhead of a drilling hole and a pipe formation body disposed in the drilling hole, and surrounds the outer periphery of the pipe formation body over the entire circumference. In this way, the outer peripheral portion is provided with a water absorption expansion member attached to the wellhead, and the water absorption expansion member absorbs water in the excavation hole from the surface and expands in volume, whereby the inner peripheral surface of the wellhead and the pipe line A wellhead seal device that seals between the outer peripheral surface of the formed body in a liquid-tight manner. The wellhead sealing device according to claim 1 or 2, wherein the water-absorbing expansion member includes a bag body having water permeability and a water-absorbing polymer accommodated in the bag body.

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