JPH02309082A - Pipeline regenerating method - Google Patents

Abstract

PURPOSE:To shorten the construction period for the regeneration of a pipeline and reduce the cost by inserting a new pipe constituted of a shape memory alloy member stored with the shape of a pipe wall in the existing pipeline, and adjusting the shape memory alloy member to the preset temperature to return it to the original shape. CONSTITUTION:A new pipe 2 shrunk in diameter is inserted into an existing pipeline 3, then the inserted new pipe 2 is expanded in diameter to provide a new pipeline in the existing pipeline 3. The new pipe 2 is constituted of a stainless shape memory alloy member 1, for example, which can be welded over the whole length in the longitudinal direction at part of the peripheral direction of a pipe wall, and the shape memory alloy member 1 is protruded to the inside and shrunk in diameter. After the new pipe 2 is inserted into the existing pipeline 3, it is adjusted to the preset temperature and expanded in diameter, and a new pipeline is installed as a new pipe 2a. As a result, the expanding work of the new pipe 2 is facilitated. No welding of the new pipe 2 is required in the longitudinal direction, thus man-hours and the cost are reduced.

Description

[Detailed Description of the Invention] [Four Fields of Application in A Business] This invention relates to a method for rehabilitating aging existing pipelines, and in particular to the Vibe-in-Vibe construction method (hereinafter referred to as PIF construction method) in which a new pipe is inserted and arranged in an existing pipeline. ).

[Conventional technology] As a construction method for rehabilitating existing pipes such as aged water transport pipes without excavating them, a new pipe is reduced in diameter and inserted into the existing pipe, and after insertion, the diameter of the new pipe is expanded. Therefore, there is a diameter-reduced PIP method in which a new pipeline is installed within an existing pipeline.

The conventional diameter reduction PIP construction method will be explained using FIGS. 3 and 4. First, in this type of conventional construction method, the new pipe 102 inserted into the existing pipe 103 buried underground (ground level GL) is inserted in the longitudinal direction of the pipe as shown in the cross-sectional view of FIG. 3A. The state in which the pipe wall to be welded is wrapped in a predetermined amount (
(referred to as a winding tube) and is fixed by a fixing fitting 106. As shown in FIG.
It is inserted into 03. Then, when a predetermined position within the existing conduit 103 is reached, the fixing fitting 106 is removed and the diameter is expanded by a jack 107 as shown in FIG. 3B. In this state, longitudinal welding (welding portion 104B) is performed, and circumferential welding (welding portion 104a) is performed to connect to the previously inserted new pipe 102b.

By sequentially connecting new pipes in this way, a new pipe line is installed within the existing pipe line.

[Problem B to be solved by the invention] However, in the conventional diameter-reduced PIP method as described above, it is possible to install a new pipe with approximately the same diameter as the existing pipe without excavating the existing pipe. Although it has the advantage of
It is necessary to adjust and weld each longitudinal joint and circumferential joint of the new pipe within the existing pipeline into which the new pipe has been inserted, which requires a long construction time and is less economical than other construction methods. There was a problem.

This invention has been made in view of these points, and aims to provide a pipe rehabilitation method that improves the conventional diameter-reduced PIP method and can shorten the construction period and reduce construction costs. It is something.

[Means for Solving the Problems] The pipeline rehabilitation method of the present invention reduces the diameter of a new pipe and inserts it into the existing pipeline, and then expands the diameter of the inserted new pipe to install a new pipe into the existing pipeline. A pipeline rehabilitation method for installing a pipeline,
In order to achieve the above-mentioned problems, a new pipe is used, in which a part of the circumferential direction of the pipe wall is made of a shape memory alloy member that memorizes the shape of the pipe wall over the entire length in the longitudinal direction. The diameter of the new tube is reduced by protruding inward,
A pipe characterized in that after inserting a new pipe with a reduced diameter into an existing pipe, the diameter of the new pipe is expanded by adjusting the shape memory alloy component material to a predetermined temperature and returning it to the memorized original shape. This is a road rehabilitation method.

[Function] In the new pipe used in the present invention, a part of the circumferential wall of the pipe wall is made of a shape memory alloy member that memorizes the shape of the pipe wall over the entire longitudinal length, and the new pipe is inserted into the existing pipe line. In some cases, the diameter is reduced by protruding the shape memory alloy member inward. After inserting the shape memory alloy member into the predetermined position in the existing pipe, the temperature of the shape memory alloy member is adjusted to above the transformation temperature. Caliber roars. At this time, since the new tube of the present invention is originally cylindrical unlike the conventional winding tube, there is no need to perform longitudinal welding after diameter expansion.

Further, in the present invention, shape memory alloy members preferably used include weldable shape memory alloy materials such as stainless steel and hard chromium.

[Example] The present invention will be explained in detail using FIGS. 1 and 2.

As shown in the cross-sectional view of FIG. is made of a stainless steel shape memory alloy member 1 (black part in the figure) that can be welded over the entire length in the longitudinal direction, and the shape memory alloy member 1 has a shape before diameter reduction (i.e., the black part in Figure 1B). shape) is memorized.

When inserting the new pipe 2 into the existing pipe 3, as shown in Fig. 1A, 1 part of the shape memory alloy member is made to protrude inward by the required amount (it is not necessary to make all 1 part of the shape memory alloy member protrude inward). ), the diameter d was set so that the new pipe 2 would not pose any problem in moving inside the existing pipe 3.

Then, the reduced diameter new pipe 2 (pipe length 4 m) is placed on rollers 5 as shown in Fig. 2, inserted into the existing pipe line 3 buried underground (ground GL), and placed in a predetermined position. When this was reached, the rollers 5 were removed, and the portion (shape memory alloy member 1 portion) that protruded inside the new tube wall was heated to about 200° C. with a gas burner.

As a result, the shape memory alloy member 1 returned to the shape before being bent as shown in FIG. .

Thereafter, the new pipe 2a with its enlarged diameter was brought into contact with the new pipe 2b already placed in the existing pipe line 3, and welding in the circumferential direction (l contact portion 4) was performed. By sequentially connecting new pipes in this way (methods other than welding may also be used), a new pipe line was installed within the existing pipe line 3 and the pipe line was rehabilitated.

Here, weld lengths will be compared between the method according to the present invention and the conventional method using a convoluted tube. Assuming that a new pipe with the same dimensions as in the above example (dimensions after diameter expansion: diameter 1000 mm, pipe length 4 m) is used, the welding length in the conventional method is 3.14 m +
4m = 7.14m, but according to the construction method of the present invention, only 3.14m in the circumferential direction is welded. As described above, the construction method of the present invention significantly reduces the man-hours and costs required for welding new pipes, and the crosspiece invention construction method, which allows for longer pipes, is advantageous.

In the above embodiments, the pipe has a cylindrical shape, but the cross-sectional shape of the pipe may be rectangular or elliptical, and the construction method of the present invention can be applied regardless of the cross-sectional shape of the pipe. In addition, in the above example, a new pipe was formed by inserting multiple new pipes into the existing pipe and connecting the stiffeners, but if the existing pipe is short or it is easy to insert new pipes, it is possible to It goes without saying that 17 new pipes will be formed by one new pipe.

[Effects of the Invention] As described above, the present invention uses a new pipe in which a part of the circumferential direction is made of a shape memory alloy member over the entire length in the longitudinal direction, and the shape memory alloy member is made to protrude inward. The diameter of the new pipe is expanded by reducing the diameter of the pipe and adjusting the temperature of the shape memory alloy member to a temperature above the transformation temperature. It is easy to expand the diameter of the pipe. Furthermore, since there is no need to weld the new pipe in the longitudinal direction, the man-hours and costs required for welding can be significantly reduced.

That is, the construction method of the present invention has the excellent effects of being able to efficiently rehabilitate pipelines in a short construction period and being economically efficient.

[Brief explanation of the drawing]

Figures 1A and B are cross-sectional views showing a reduced diameter state and an expanded diameter state of the new pipe used in the embodiment of the present invention, respectively, and Figure 2 is a cross-sectional view illustrating the construction method of the embodiment of the present invention. Figures 3A and 3B are sectional views showing a reduced diameter state and an enlarged diameter state of the new pipe in the conventional construction method, respectively, and FIG. 4 is a sectional view for explaining the conventional construction method. [Explanation of symbols of main parts...Shape memory alloy member 2...New pipe with reduced diameter 2a...New pipe with enlarged diameter 3...Existing pipe line 4...Welded part 5... ·roll

Claims (1)

[Claims] In a pipeline rehabilitation method in which a new pipe is created within an existing pipe by reducing the diameter of the new pipe and inserting it into the existing pipe, and then expanding the diameter of the inserted new pipe, the new pipe is Using a new tube made of a shape memory alloy member in which a part of the circumferential direction memorizes the shape of the tube wall over the entire length in the longitudinal direction, the diameter of the new tube is reduced by making the shape memory alloy member protrude inward. After inserting a new pipe with a reduced diameter into an existing pipe line, the new pipe is expanded in diameter by adjusting the shape memory alloy member to a predetermined temperature and returning it to the memorized original shape. Pipe rehabilitation method.