JPH0343504Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial field) The invention relates to a jig for drawing multiple conduits for accommodating communication cables, etc. into small diameter tunnels constructed by propulsion of steel pipes, etc. It is.

(Prior art) When pulling multiple pipes into a small-diameter tunnel as described above, there is no gripping method that reliably transmits the traction force of the wire to the pipes, and there is also a possibility that the pipes may be damaged during drawing due to poor pipe connections. Conventionally, pipes were made of steel or a sled was installed under the pipes to be led in, because there was a risk of parts coming off, and the pipes could get stuck on the uneven surface of the tunnel, making it impossible to pull them in. A commonly used method is to process this end and apply traction force to pull it in.

(Problem that the invention aims to solve) In the conventional method as described above, the sled is left in the tunnel along with the pipe, so it is disposable during each construction work.
The processing cost is also high, which increases the construction cost, and the height of the warp creates a dead space within the tunnel, resulting in a problem that the utilization efficiency of the cross section of the tunnel interior becomes low.

In consideration of the above points, the present invention can be used repeatedly, reduces construction costs, makes effective use of the tunnel cross section, and can grip the pipe without any processing, so that it can be used in the event that the pipe connection becomes detached. The present invention provides a conduit drawing jig for recovering the conduit from inside the tunnel or preventing its separation, and also for smoothly drawing the conduit into the tunnel.

(Structure of the invention) Fig. 1 shows an embodiment of the invention, in which 1 is a bowl-shaped jig body whose tip outer periphery faces backward and forms a curved surface, 2 is a pipe gripper; An elastic body 3 made of rubber or the like is sandwiched between plate bodies 4 on both sides, a bolt 5 is passed through the elastic body 3 and both plates 4, a pipe 6 is inserted into the bolt 5, and a nut 7 is turned around the pipe 6. By this, the elastic body 3 is compressed and expanded in diameter, and the pipe line 10 is gripped from inside.The tip of the bolt 5 is fixed to the jig body 1 by nuts 8 and 9. Ru. 11 is one of the pipes
The rod is inserted through two conduits 10, and its tip and rear ends are threaded, and the tip is attached to the jig body 1 with a nut 12. 13 is a towing hook for attaching a towing wire.

FIG. 2 shows a state in which a pipe is drawn in using the jig of the present invention. 2 to the jig body 1, and insert and enlarge the elastic bodies 3 of the conduit gripper 2 into each of the other required number of conduits 10 to grip them, and attach them to the jig body 1. The tips of all the pipes are inserted, and the pipe groups are tied together with a band 17, and the rear end of the traction wire 19 is connected to the jig main body 1.
It can be pulled into the tunnel 14 by attaching it to the towing hook 13 and pulling the towing wire 19 with a winch or the like. The pipes 10 are connected at the connecting portion 18 and the rods 11 are also connected, and the pipes 10 are bundled and pulled in one after another. At this time, since the jig body 1 is bowl-shaped, it is smoothly pulled in without getting caught on the unevenness of the inner surface of the tunnel.
In addition, even if the pipe connecting part should come off due to the rod 11, it can be recovered by pulling its rear part in the opposite direction, or it can be recovered by pulling the rear part of the pipe in the opposite direction. All pipes 1
If an anchor 20 for preventing separation of the conduit connection part is attached to hold the rear end of the pipe connection part 0, separation at the conduit connection part can be prevented. When the pipe 1 has been drawn into the tunnel 14 and its tip reaches the shaft 16, the jig body 1, pipe grip 2, and rod 11 can be removed and collected in preparation for reuse elsewhere. can.

(Effects of the invention) As described above, by using the jig of the invention and conduit bundling with bands, it is possible to draw in by direct towing, and the inner cross section of a small diameter tunnel can be efficiently utilized. In addition, the pipe gripper, which grips the pipe by inserting it into the pipe and expanding its diameter, can hold the pipe without machining it. It can be smoothly retracted without getting stuck even when the inner surface is uneven, and on the other hand, the rod that is attached to the jig body and inserted through the pipe line allows the pipe body to be recovered when the pipe connection part is separated. Alternatively, by attaching an anchor to this rod to prevent separation of the pipe connection part, separation of the pipe connection part can be prevented. Furthermore, since it can be recovered and used repeatedly after the pipeline is installed, construction costs can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the embodiment of the present invention in use, and FIG. 2 is an explanatory view showing one state in which the jig of the present invention is being used to draw in a pipe. DESCRIPTION OF SYMBOLS 1...Jig main body, 2...Pipe gripper, 3...Elastic body, 10...Pipe line, 11...Rod, 13...
Towing hook, 17...Band, 18...Connection part, 20...Anchor for preventing separation of pipe connection part.

Claims (1)

[Scope of utility model registration request] A pipe line drawing jig for drawing a plurality of pipe lines each having a connection part into a small-diameter tunnel includes a bowl-shaped jig main body into which all the tips of the pipes are inserted, and a main body for drawing the pipes each having a connection part. A rod that is inserted through one of the pipes and whose tip end is detachably attached to the jig main body, and a rod that is expanded in diameter to the inner periphery of the tips of all the pipes that are not inserted. a conduit gripper which has an elastic body at its rear end that can be crimped by the user, and whose tip end is detachably attached to the jig body; a towing hook attached to the jig body; A conduit drawing jig, characterized in that it is equipped with a band for binding, and an anchor for preventing detachment of a conduit connection part, which is attached to the rear protrusion of the conduit of the rod and holds down all the rear ends of the conduit. .