JPH0649663Y2 - Shield well packing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a packing device for a shield wellhead.

More specifically, the present invention relates to a technique for improving the sealing property of a packing device that seals between a well of a shield pit and a shield machine when excavating the soil by a shield construction method in which a shield machine is excavated and propelled from a vertical shaft.

[Prior Art] Conventionally, as a packing device for a shield wellhead, for example, those shown in FIGS. 4 and 5 are known.

In this conventional shield pit mouth packing device, a large number of bolts 1 that are fixed to the periphery of the shield pit T in the axial direction of the shield pit and are fixedly arranged along the periphery of the shield pit T at regular intervals are provided. The mounting hole 21 inserted into the bolt 1 has a long hole shape extending in the radial direction of the shield well T, and its mounting position is radially arranged along the peripheral edge of the shield well T, which is variable in the radial direction of the shield well. A plurality of holding metal fittings 2, a nut 3 that is screwed into the bolt 1 from the outside of the holding metal fitting 2 that is inserted into the bolt 1, and tightens the holding metal fitting 2; and a nut 3 that is tightened by the nut 3 through the holding metal fitting 2 T and a packing material 4 such as rubber that seals between the shield machine S. In addition, this press fitting 2
Is for supporting the packing material 4 that receives the shield underground pressure P from the back.

According to this conventional shield pit packing device, when the eccentricity in which the axis of the shield machine S deviates from the axis of the shield pit while the shield machine S is being excavated,
Loosen the nut 3 and hit the head or the bottom of the holding metal fitting 2 to move the holding metal fitting 2 in either radial direction of the shield well T, thus changing the mounting position of the holding metal fitting 2 and pressing the metal fitting 2 and the shield. In addition to preventing contact damage with the machine S, the holding metal fitting 2 is positioned over the entire back portion of the packing material 4 to support the packing material 4 receiving the shield underground pressure P from the back portion.

[Problems to be Solved by the Invention] In the above-described conventional shield pit packing device, since the nut 3 is loosened when the holding metal fitting 2 is moved, the tightening of the packing material 4 to the shield pit T is loosened, and the shield pit T is connected. Sediment, muddy water, etc. are ejected together with the shield mine pressure P from the gap between the packing material 4 and the packing material 4
Has a problem in that it is turned outward near the shield machine S, and the shield underground pressure P is ejected from there.

It should be noted that such a spout of the shield pit pressure P causes the collapse of the shield pit, and a large amount of once ejected large amounts of earth and sand or muddy water fills the vertical shaft, thus delaying the construction period. There is. Therefore, it has the technical background that it is necessary to take a very strict preventive measure.

The present invention has been made in consideration of such problems and technical background, and packing of a shield well hole that enables movement of a holding metal fitting corresponding to eccentricity of a shield machine without loosening the tightening of the packing material. An object is to provide a device.

[Means for Solving the Problem] In order to achieve the above-mentioned object, a packing device for a shield well according to the present invention includes a bolt fixed to the periphery of the shield well in the axial direction of the shield well and inserted through the bolt. The mounting metal fittings, which are mounted in a long hole shape that extends in the radial direction of the shield well, and whose position is variable in the radial direction of the shield well, are screwed onto the bolts from the outside of the holding metal fittings inserted into the bolts. In a shield pit packing device consisting of a nut that tightens the metal fittings and a packing material that is tightened by the nuts via the holding metal fittings and seals between the shield well and the shield machine, the nuts are not inserted into the mounting holes of the holding metal fittings. The means is characterized in that the packing material is screwed onto the bolt and the packing material is directly or indirectly tightened independently of the holding metal fitting.

[Operation] According to the above-described means, in addition to the nut that is screwed to the bolt from the outside of the pressing metal fitting through the pressing metal fitting, the bolt or the separate bolt that individually fixes the packing material is screwed to the presser foot. Since the nut for tightening the packing material is provided separately from the metal fitting, the tightening of the packing material does not loosen even if the nut screwed to the bolt via the holding metal fitting is loosened to move the holding metal fitting. Therefore, the problem to be solved is to provide a packing device for a shield wellhead which can move a holding metal fitting corresponding to an eccentricity of a shield machine without loosening the packing material.

Since the nut for fastening the packing material separately from the holding metal fitting is housed in the mounting hole, there is no hindrance to the movement of the holding metal fitting.

[Embodiment] An embodiment of the packing device for the shield wellhead according to the present invention will be described below with reference to FIGS. 1 to 3.

This embodiment basically has the same structure as the above-mentioned conventional example shown in FIGS. 4 and 5, and shows a shield machine around the starting hole.

In this embodiment, the short width of the long hole-shaped mounting hole 21 of the holding metal fitting 2 of the above-mentioned conventional example is usually the same as or slightly larger than the diameter of the bolt 1, but it is shown in detail in FIG. As described above, the width W is widened so that the nut 5 can be accommodated therein. The nut 5 can be screwed into the bolt 1 by rotating in the mounting hole 21 of the holding metal fitting 2, and the packing material 4 can be tightened independently of the holding metal fitting 2. Further, the nut 5 is formed thinner than the thickness of the holding metal fitting 2 so as not to project from the holding metal fitting 2. Alternatively, although not shown, at least one of the bolts 1
The book may be an embodiment dedicated to tightening the packing material 4. In other words, the bolt 1 for fixing only the packing material is provided separately from the bolt to be screwed to the nut 5 from the outside of the holding metal fitting through the holding metal fitting, and the bolt 1 for fixing the packing material is provided in the long hole-shaped mounting hole 21.
The packing material may be tightened independently of the holding metal fitting by inserting the nut 3 having a small width into the fitting material.

In addition, an unexplained part common to the above-mentioned conventional example will be described below. That is, the bolt 1 is fixed to the rib member 6 fixed to the shield well T by welding, and the bolt 1 is arranged on the radial line of the shield well T in order to equalize the tightening.
Books are set up side by side. Further, a flat plate-shaped contact plate 7 is interposed between the holding metal fitting 2 and the packing material 4 to avoid friction with respect to the packing material 4 when the holding metal fitting 2 is displaced to facilitate the movement of the holding metal fitting 2. . Accordingly, the nut 5 can indirectly tighten the packing material 4 via the contact plate 7. Further, a washer 8 is interposed between the press fitting 2 and the nut 3.

According to such an embodiment, when eccentricity of the shield machine S occurs, the outermost nut 3 is loosened and the holding metal fitting 2 is struck, as in the above-described conventional example, to shield the tunnel well T. To move the pressing metal fitting 2 in any radial direction to change the mounting position of the pressing metal fitting 2. However, unlike the conventional example,
Since another nut 5 tightens the packing material 4 to prevent it from loosening, problems such as ejection of the pressure P in the shield hole due to loosening of the packing material 4 will not occur.

As shown in FIG. 3, when the tip 22 of the holding metal fitting 2 is formed in a curved shape, the packing material 4 can be smoothly deformed, and the support against the shield underground pressure P can be strengthened to effectively prevent reversal. There is an advantage that can be. The shape of this curved shape and the angle θ can be set freely.

As described above, in addition to the illustrated embodiment, it is also possible to carry out at the reaching well entrance of the shield pit, in which case the packing material 4 is deformed in the direction opposite to the drawing.

Further, it is possible to use an embodiment in which the packing material 4 is directly tightened with the nut 5 without the contact plate 7 interposed.

[Advantages of the Invention] As described above, the shield pit packing device according to the present invention has the effect of enabling the movement of the press fitting corresponding to the eccentricity of the shield machine without loosening the tightening of the packing material. Further, due to this effect, it is possible to surely prevent the pressure in the shield tunnel from being blown out, thereby improving the safety of the work and improving the work efficiency of the work.

Further, since the double tightening structure using two nuts can be performed, the degree of tightening of the packing material is increased and the sealing property is increased.

Further, the structure is simple and the manufacturing cost is low, and the existing product can be modified.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a packing device for a shield wellhead according to the present invention, FIG. 2 is a sectional view taken along the line XX of FIG. 1, and FIG. 3 is a modification of FIG. 4 is a front view showing a conventional example, and FIG. 5 is an enlarged cross-sectional view taken along line YY of FIG. 1 ... Bolt, 2 ... Holder fitting 3 ... Nut, 4 ... Packing material 5 ... Nut S ... Shield machine T ... Shield wellhead

Claims (1)

[Scope of utility model registration request] 1. A bolt fixed to the periphery of the shield well so as to project in the axial direction of the shield well, and a shield well which is attached to the shield well in the form of an elongated hole extending in the radial direction of the shield well. With a press fitting that can change the position in the radial direction,
Packing the shield well with a nut that is screwed into the bolt from the outside of the hold-down fitting that is inserted into the bolt to tighten the hold-down fitting, and a packing material that is tightened by the nut through the hold-down fitting to seal between the shield well and the shield machine. In the device, the nut is screwed into the bolt in the mounting hole of the holding metal fitting and the packing material is directly or indirectly tightened independently of the holding metal fitting separately from the holding metal fitting. Packing equipment.