JPS61242300A - Cylindrical pipe for cutting with invisible chip - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an arrangement of cutting tips for cylindrical pipes used in underground pipe propulsion methods for burying sewer pipes, cable laying pipes, etc., underground on steel pipe piles. .

[Conventional technology]

As an example, we will discuss the pilot propulsion pipe construction method.

When constructing small-diameter sewage pipes of approximately 250 to 1000 mmφ using the buried pipe propulsion method, a propulsion device is installed in the starting shaft, a striking hammer is attached to the tip of the pilot pipe, an auger is inserted into the pilot pipe, and the pilot The pilot tube is propelled by rotating the tube and auger in opposite directions.

A cylindrical cutting tube is attached to the tip of the pilot tube and has a cutting tip fixed thereto for expanding the excavated portion excavated by the impact hammer and propelling the pilot propulsion tube.

The buried pipe propulsion method is often constructed on ground containing gravel or gravel layers, and the cutting tip attached to the tip of the viroft tube uses rotational force to cut through these layers, resulting in severe wear of the cutting tip. When the cutting tip wears out, the base alloy portion in which the cutting tip is embedded rapidly wears out.

Further, when some of the cutting tips wear out, the load on the other cutting tips increases, so that their wear is further accelerated.

[Problem that the invention seeks to solve]

In this invention, when the cutting tips of the underground pipe propulsion method are worn out, another cutting tip (hereinafter referred to as a hidden tip) is used to replace them, so that cutting can be continued. The purpose of the present invention is to provide a cutting tool that can deal with the wear of cutting tips and has a long life.

[Means for solving problems]

The technical means of the present invention will be explained with reference to FIG. 1, which is an embodiment thereof. In a pilot propulsion tube having a cylindrical cutting tube 2 having a large number of cutting tips fixed to the tip thereof, a cutting tip 1 of the cylindrical tube is provided. This cylindrical tube for cutting is equipped with a hidden tip, characterized in that a recess is formed in the alloy part 3 between them, and a hidden tip 11 that is activated when the cutting tip 1 is worn is mounted in the recess.

[Effect]

The conventional tip 1 shown in FIG. 1 is worn out.

When the alloy part 3 of the embedded base rapidly wears out, the hidden tip 11 performs a cutting action. Therefore, the life of the cutting tool is long and interruptions in construction work can be avoided.

〔Example〕

FIG. 1 shows the tip of a pilot tube according to an embodiment of the present invention, in which (a) is a front view, (b) is a partially cutaway side view, and (c) is a cutting bit arrangement part of the whipstock. FIG. 2(a) is a front view of the embodiment of the cutting cylindrical tube, FIG. 2(b) is a view taken along the line A-A, and FIG. 2(C) is a partial perspective view.
is a partially exploded view of the cutting tip attachment part.

In this embodiment, in addition to the conventional cutting tip l attached to the tip of a whipstock 2 that incorporates a plurality of down-the-hole hammers 4, there is also a hidden tip 11 (shown with diagonal lines) according to the present invention. ) is installed.

The hidden tip 11 is attached to a recess 12 formed in the alloy part 3 between a number of conventional cutting tips l. In Figure 0, the hidden tip is attached to the groove bottom of the recess 12. However, it may also be attached to the sloped part of the groove. In Fig. 1(C), the conventional cutting tip 1 is worn out, and then the base metal i3 is worn out. This is illustrated as part 13. In this way, conventional cutting 1,000-2
When the tip 1 wears out, the alloy part 3 wears out in a short period of time, and the hidden tip 11 performs cutting.

〔Effect of the invention〕

Since the present invention is configured as described above, even if the cutting tip wears out, the hidden tip continues cutting, extending the life of the cutting tool, avoiding interruptions in construction, and improving efficiency and reducing costs. It has excellent effects such as contributing to

Especially when there are boulders, the blades embedded at the same level will be damaged almost simultaneously, resulting in a decrease in cutting efficiency during the next normal propulsion.The advantage is that the hidden chips can remain completely intact in this case. Can be mentioned.

Furthermore, the present invention can be applied not only to the cutting tip at the tip of a cylindrical cutting tube, but also to other general poling bits, rock drill cutters, crowns, and the like.

[Brief explanation of drawings]

FIG. 1 shows details of the pilot tube tip of an embodiment of the present invention, (a) is a front view, (b) is a partially cutaway side view, (
c) is a partial perspective view of the cylindrical tube for cutting, FIG. FIG. 3 is a partially exploded view of the attachment part. l... Cutting tip 2... Cutting cylindrical tube 3... Base metal part 4... Town-the-hole hammer 11... Hidden tip 12... Recessed part 13... Worn part Application person Tokyu Construction Co., Ltd. Koken Drilling Industry Co., Ltd.

Claims (1)

[Claims] 1. A cutting device equipped with a hidden tip, characterized in that a cylindrical tube has a large number of cutting tips fixed to its tip, a recess is formed between the cutting tips, and another cutting tip is attached to the recess. For cylindrical tubes.