JPH0158320B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for simultaneously laying a plurality of pipelines in parallel.

Next, the present invention will be explained in detail using illustrated examples.

The drawing shows an embodiment of the present invention, in which a small-diameter leading drill pipe 2 is inserted into a small-diameter drill hole 1, which is curved or straight, excavated while performing track control. Excavation bit 3
are connected, and the front end of the small-diameter subsequent drill pipe 4 is also connected, and a holding member 9 is fixed inside the front end of the sheath pipe 5, which has an outer diameter slightly smaller than the diameter of the hole expanded by the drilling bit 3, and holds it. A trailing drill pipe 4 is fitted into the center of the member 9 via a bearing 10 so as to be rotatable and immovable in the axial direction, and further,
A covering cylinder 11 is installed across a small diameter portion provided at the rear end of the excavation expanding bit 3 and a small diameter portion provided at the front end of the holding member 9. The drilling bit 3 is provided with a muddy water chamber 12 that communicates with the inside of the drill pipe, and the front part of the drilling drilling bit 3 is provided with a muddy water spout hole 13 that communicates with the muddy water chamber 12.
is provided.

The proximal end of a connecting member 6 is fixed to the side, for example, the lower part of the front end of the sheath tube 5, and the front end of a small diameter pipe 7, which is laid parallel to the sheath tube 5, is attached to and detached from the distal end of the connecting member 6. The tip of a screw-type rotary excavator 8 which is freely threadedly connected and arranged parallel to this at the front of the connecting member 6 is rotatably supported by the tip of the connecting member 6. A shaft portion 14 at the proximal end of the tool 8 is rotatably supported by a bearing 15 provided at the proximal end of the connecting member 6. Further, the driving bevel gear 17 that meshes with the driven bevel gear 16 fixed to the shaft portion 14 is fixed to a holding cylinder 18 that is fitted and fixed to the trailing drill pipe 4, and the holding cylinder 18 is fixed to the sheath pipe 5. It is rotatably supported by a bearing 19.

When the sheath pipe 5 and the small diameter pipe 7 are propelled and laid in parallel, a propulsion device (not shown) is used.
The sheath pipe 5 grasps and propels the rear end of the sheath pipe 5, and the small diameter pipe 7 is propelled by the sheath pipe 5 via the connecting member 6, and the drill pipes 2, 4 are driven by a drive device provided in the propulsion device. At the same time, the screw-type rotary drilling tool 8 is rotated by the following drill pipe 4 via the driving bevel gear 17 and the driven bevel gear 16, and muddy water is supplied from the rear end of the following drill pipe 4. The muddy water is ejected from the spout hole 13 of the excavation expanding bit 3, and the ground in front of the sheath pipe 5 is expanded by the excavation expanding bit 3.
The ground in front of the connecting member 6 is excavated.

The earth and sand excavated by the excavation expanding bit 3 are passed through the large diameter excavation hole 20 excavated by the excavation expanding bit 3.
The earth and sand excavated by the screw-type rotary excavator 8 are transferred to the sheath pipe by the feeding action of the screw 21 in the rotary excavator 8 and are discharged to the ground by the mud flow passing between the sheath pipe 5 and the screw type rotary excavator 8. 5, and then discharged to the ground together with excavated soil by the excavation bit 3 by a mud flow.

In this way, the sheath pipe 5 and the small diameter pipe 7 are propelled underground in a parallel state, and after the sheath pipe 5 and the small diameter pipe 7 reach another surface or a recess dug from the ground surface, the advancing operation is stopped, and the sheath pipe At the same time as pulling out the drill pipe 4 from the connecting member 6, cut the sheath pipe and small diameter pipe at a position slightly behind the connecting member 6, remove the part in front of the cut part, and use the remaining sheath pipe and small diameter pipe as appropriate. Use for various purposes.

According to the present invention, a drilling bit 3 is connected to the rear end of a small-diameter leading drill pipe 2 inserted into a small-diameter excavated hole 1, and a small-diameter trailing drill pipe 4 and a sheath pipe 5 surrounding it are connected. The excavation expanding bit 3 is rotated by the drill pipe, and the sheath pipe 5 is propelled while discharging the earth and sand excavated by the excavation expanding bit 3 through the outside of the sheath pipe 5 by a flow of mud. In the laying method, the front end of a small diameter pipe 7 laid parallel to the sheath pipe 5 is connected to the distal end of the connecting member 6 whose base end is attached to the side of the front end of the sheath pipe 5, and the A screw-type rotary excavator 8 provided at the front of the connecting member 6 propels the sheath pipe 5 while excavating earth and sand at the front of the connecting member 6, and thereby excavates the small diameter pipe 7 through the connecting member 6. Since it is propelled, the thrust resistance of earth and sand is prevented from acting on the connecting member 6, and the sheath pipe 5
and a small-diameter pipe 7 parallel to this can be easily laid with a relatively small propulsive force, and furthermore, the earth and sand excavated by the screw-type rotary excavator 8 is transferred to the screw 21 of the rotary excavator 8. After being transported toward the sheath pipe 5 by the feeding action, it is flown backward by the mud flow through the space between the sheath pipe 5 and the large diameter concave excavation hole 20 expanded by the drilling bit 3. Therefore, the earth and sand excavated by the screw-type rotary excavator 8 can be easily discharged using the mud flow for excavation expansion. In addition, when propulsion-laying a single large-diameter pipe, considerably large propulsion equipment is required, but in the case of this invention, multiple pipes having the required total cross-sectional area are divided, and
Since excavation propulsion is carried out as described above, propulsion can be carried out using relatively small-capacity propulsion equipment, and furthermore, it is possible to carry out propulsion using relatively small-capacity propulsion equipment. Since the drill is guided and propelled by the preceding drill pipe 2, effects such as being able to propel in parallel along a predetermined trajectory while maintaining an accurate positional relationship can be obtained.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a vertical cross-sectional side view showing a state in which multiple pipelines are laid in parallel, and Fig. 2 shows the support part and the screw-type rotary excavator. 3 is a sectional view taken along the line AA in FIG. 1, and FIG. 4 is a sectional view taken along the line BB in FIG. 2. In the figure, 1 is a small diameter drilling hole, 2 is a leading drill pipe, 3 is an expansion bit, 4 is a succeeding drill pipe, 5 is a sheath pipe, 6 is a connecting member, 7 is a small diameter pipe,
8 is a screw type rotary excavation tool, 9 is a holding member, 1
0 is a bearing, 13 is a mud water spout, 15 is a bearing, 16
is a driven bevel gear, 17 is a driving bevel gear, 19 is a bearing,
20 is a large-diameter drilling hole, and 21 is a screw.

Claims (1)

[Claims] 1 Connect the drilling expansion bit 3 to the rear end of the small-diameter leading drill pipe 2 inserted into the small-diameter drilling hole 1, and connect the small-diameter trailing drill pipe 4 and the sheath pipe 5 surrounding it, and In this method, the sheath pipe 5 is propelled and laid while the excavation expanding bit 3 is rotated by a pipe and the earth and sand excavated by the excavation expanding bit 3 is discharged through the outside of the sheath pipe 5 by a flow of mud. The front end of a small-diameter pipe 7 laid parallel to the sheath tube 5 is connected to the distal end of a connecting member 6 whose proximal end is attached to the side of the front end of the sheath tube 5. The connecting member 6 is
A method for laying a plurality of pipelines in parallel, characterized in that the sheath pipe 5 and the small diameter pipe 7 are simultaneously propelled and laid in a parallel state while excavating earth and sand in the front part of the pipe and transporting it toward the sheath pipe 5.