JP7429947B2 - Piping renewal method - Google Patents

Description

The present invention relates to a piping renewal method for replacing existing piping covered with a protective material such as a heat insulating material with new piping.

Piping covered with a protective material such as a heat insulator is widely used. Such piping is, for example, a hot water supply piping installed in a building that connects a water heater and a location to which hot water is to be supplied. Alternatively, connect the water meter and the target water supply area as a water supply pipe. These pipes are installed under the floor of a building.

Depending on the extent to which this piping has deteriorated over time, the piping may be updated. Conventionally, in such cases, the protective material and piping were all replaced.

On the other hand, Patent Document 1 describes a method for updating piping covered with a protective material (according to the description in Patent Document 1, a "protective tube"). According to this construction method, the existing piping is pulled out from the protective material, and then the new piping is passed through the existing protective material to renew the piping.

Japanese Patent Application Publication No. 2004-150145

However, with conventional construction methods, work cannot be done without temporarily dismantling a part of the building (for example, the flooring if the piping is installed under the floor) and exposing the protective material and piping. There wasn't. For this reason, the renewal work became large-scale, and the construction cost was correspondingly large.

Furthermore, in the construction method described in Patent Document 1, protective materials and pipes are laid in buildings etc. in advance when newly installing pipes, taking into consideration the ease of pulling out the pipes. For this reason, it took a lot of time and effort to install new pipes as the shape of the pipes had to be taken into account. Additionally, there were some pipes, such as metal-reinforced resin pipes, that could not be constructed in this way.

Therefore, an object of the present invention is to provide a piping renewal method that eliminates the need for demolition of buildings as much as possible when renewing piping, and does not require special consideration when installing new piping.

The present invention is a piping renewal method for replacing existing piping covered with a tubular protective material with new piping, in which the existing piping is cut in the radial direction and in the pipe axial direction at one point in the circumferential direction. a step of cutting the existing pipe to expand the diameter of the existing pipe; and a step of expanding the diameter of the existing pipe, and cutting the new pipe to the diameter-enlarged existing pipe without removing the protective material and the existing pipe from the object to which the existing pipe is installed. This piping renewal construction method is characterized by including the step of inserting a new pipe into the inside of the protective material and the existing piping while along the inner circumferential surface of the piping.

According to the above configuration, the existing pipe and the protective material can be left fixed to the object to be installed such as a building, and the existing pipe whose diameter has been expanded can be used as a guide when installing the new pipe. Moreover, since there is no need to pull out the existing piping, the piping can be easily replaced without being affected by the installed shape of the piping.

The method further includes a grooving step of forming a groove along the pipe axis direction on the inner circumferential surface of the existing pipe prior to the existing pipe cutting step, and in the existing pipe cutting step, the groove formed in the grooving step is The existing piping can be cut along.

According to the above configuration, by cutting the existing pipe using the groove formed in the grooving process as a guide, reliable cutting is possible without failure in cutting in the existing pipe cutting process.

Further, in the existing pipe cutting step, the cutting can be performed without performing any prior processing on the inner circumferential surface of the existing pipe.

According to the configuration, a series of steps can be shortened by performing the existing pipe cutting step without performing any prior processing.

Further, the existing pipe cutting step and the new pipe insertion step may be performed at an end portion of the existing pipe and the protective material exposed to the outside of the building.

According to the above configuration, work can be performed at the ends of the existing piping and protective material exposed to the outside of the building, so there is no need to demolish the building, which can contribute to lower construction costs.

Further, two winches capable of winding up the cable-like body are used, one of the two winches is placed at one end of the existing piping and the protection material, and one of the two winches is placed at one end of the existing pipe and the protection material. Another winch on the other side is arranged at the other end of the existing piping and the protective material, and the end of the cable-shaped body of the winch on the one side and the end of the cable-shaped body of the winch on the other side are arranged. A piping processing jig is connected to the existing piping so that it can pass through the inside of the existing piping, and the one side winch and the other side winch are alternately operated to process the piping on the existing piping. The jig may be moved back and forth, and the existing pipe cutting step and the diameter expanding step may be performed along with this reciprocating movement.

According to the above configuration, the existing pipe cutting process and the diameter expanding process are performed by using two winches and reciprocating the pipe processing jig connected to the cable-shaped body. Therefore, preparations for inserting new piping can be made efficiently.

According to the present invention, an existing pipe whose diameter has been expanded can be used as a guide when installing a new pipe. Moreover, the piping can be easily updated without being affected by the installed shape of the piping. Therefore, when updating the piping, it is not necessary to demolish the building, and there is no need to take special consideration when installing new piping.

FIG. 1 is a schematic diagram showing an example of the arrangement of piping, which is a target of a piping renewal method according to an embodiment of the present invention, in a building. FIG. 2 is a schematic diagram showing a combination of a winch and a pipe cutting jig used in the pipe renewal method. (a) is a half sectional view of the pipe cutting jig. (b) is a plan view of the first blade attached to the pipe cutting jig. (c) is a plan view of a second cutter attached to the pipe cutting jig. (d) is a plan view of a third blade attached to the pipe cutting jig. FIG. 2 is a half-sectional view of a pipe diameter expansion jig used in the pipe renewal method. (a) is an axial cross-sectional view showing a preparatory stage of a grooving process in the pipe renewal method. (b) is an axial cross-sectional view showing the grooving process (first stage). (c) is a radial cross-sectional view of the existing pipe after the grooving process (first stage). (d) is an axial cross-sectional view showing the grooving process (second stage). (e) is a radial cross-sectional view of the existing pipe after the grooving process (second stage). (a) is an axial cross-sectional view showing an existing pipe cutting process in the pipe renewal method. (b) is a radial cross-sectional view of the existing pipe after the existing pipe cutting process. (c) is an axial cross-sectional view showing a diameter expansion process. (d) is a radial cross-sectional view of the existing piping after the diameter expansion process. (a) is an axial sectional view showing a new pipe insertion process in the pipe renewal method. (b) is an axial cross-sectional view showing the state after new piping is installed. (c) is a radial cross-sectional view showing the state after new piping is installed.

First, the present invention will be explained by taking up one embodiment. FIG. 1 shows an example of the arrangement of existing piping Po, which is the target of the piping renewal method of this embodiment, in a building. The existing pipe Po is, for example, a pipe for supplying hot water, and its outer periphery is covered with a tubular protective material G. The existing pipe Po and the new pipe Pn are resin pipes, such as polyethylene pipes (PE pipes), crosslinked polyethylene pipes (PE-X pipes), and polybutene pipes (PB pipes). The resin tube can also be a multilayer tube with metal layers such as aluminum alloy sandwiched therebetween. The protective material G has an inner diameter larger than the outer diameter of the existing pipe Po (especially before diameter expansion) and the new pipe Pn, is made of a flexible material such as foamed resin, for example foamed polyethylene, and has a diameter It has the function of insulation and heat retention in the direction. Regarding the above-mentioned "flexible", in this embodiment, when the protective material G receives an external force from the new pipe Pn when inserting the new pipe Pn, deformation such as displacement of the axis line or compressive deformation in the radial direction occurs. It suffices to have as much flexibility as possible. By the way, in conventional construction methods (for example, see Japanese Unexamined Patent Publication No. 2004-150145 (Patent Document 1)), when pulling out existing piping from the protective material, or when passing new piping through the existing protective material, foamed resin, etc. If a protective material made of a flexible material is used, the piping will break through the protective material at the corner or band fixing portion and be damaged. In other words, conventional construction methods cannot be applied to protective materials made of flexible materials.

FIG. 1 shows an example of the arrangement of existing piping Po in a building (for example, a house) C. Note that the new piping Pn after the piping update is also arranged in the same form as the existing piping Po in the building C. The existing pipe Po is covered with the floor material F at least in the middle in the pipe axis direction. Note that "pipe axis direction" means a direction along the axial center of the existing pipe Po. In addition, the inlet end and outlet end of the existing pipe Po in the pipe axis direction are exposed upward from the flooring F or laterally from the outer wall, and the inlet end of the existing pipe Po is connected to, for example, a water heater (not shown). The outlet end is connected, for example, to a bathroom faucet V. The existing pipes Po are fixed to the foundation B located below the flooring F at predetermined intervals in the pipe axial direction with bands or the like so that they do not become violent due to the water pressure during water flow. When fixing, as shown in FIG. 1, the protective material G receives an external force in the radial inward direction by the band etc. and the base B, and the outer diameter of the protective material G made of a flexible material such as foamed resin receives the external force. is compressed and reduced in diameter.

Next, the apparatus and jig used in the pipe renewal method of this embodiment will be explained. In this embodiment, a winch (winding machine) 1, a pipe processing jig 2 (a pipe cutting jig 2A, a pipe diameter expanding jig 2B), and a pipe insertion jig 3 are mainly used.

Two winches 1 are used as a set. One winch 1 is placed at each end of the pipe to be constructed. The winch 1 is configured to be able to wind up a wire 11 that is a cable-like body. One winch 1 is disposed at one end of the existing pipe Po, and the other winch 1 is disposed at the other end. When the wire 11 is connected between the two winches 1, one of the winches 1 in the set generates a tensile force as the wire 11 is wound up, and the other winch 1 receives the tensile force. Wire 11 is pulled out. The winch 1 may be driven manually, or may be driven by a motor such as an electric motor.

A jig connection portion 12 is provided at the tip of the wire 11. The jig connection part 12 includes a wire side connection part connected to the wire 11, a jig side connection part connected to the pipe cutting jig 2A, and a jig side connection part that rotates with respect to the wire side connection part. and a rotary connection part that connects both the connection parts so that the connection parts can be connected together. A bearing 121 is built into the jig connection part 12 as this rotational connection part. This bearing allows the jig connection portion 12 to rotate in the circumferential direction relative to the wire 11. Thereby, the pipe cutting jig 2A (more specifically, the blade 4 attached to the pipe cutting jig 2A) connected to the wire 11 can be shifted in the circumferential direction. Therefore, in the grooving process and the existing pipe cutting process, which will be described later, even if the wire 11 is twisted, the pipe cutting jig 2A is not affected by the twist, and the pipe cutting jig 2A is not affected by the twist, and the pipe cutting jig 2A is The pipe cutting jig 2A can be moved in the pipe axis direction while maintaining a fixed position. Further, even if the pipe cutting jig 2A receives resistance from the existing pipe Po when moving within the existing pipe Po, it rotates relative to the wire 11 to alleviate the resistance, so that machining resistance can be suppressed.

The jig connection parts 12 of this embodiment are provided at one axial end side and the other axial end side of the pipe cutting jig 2A, and one jig connection part 12 connects one wire 11 to the pipe cutting jig. 2A, and the other jig connecting portion 12 connects the other wire 11 to the other end of the pipe cutting jig 2A. The connected wire 11 extends coaxially with respect to the pipe cutting jig 2A.

The pipe cutting jig 2A has a substantially cylindrical shape with a reduced diameter at both ends in the longitudinal direction. This pipe cutting jig 2A functions as a pipe processing tool in combination with the jig connection part 12. A half cross-sectional shape of the pipe cutting jig 2A when viewed from the side is shown in FIG. 3(a). The outer diameter of the large diameter portion on the longitudinal center side of the pipe cutting jig 2A is smaller than the inner diameter of the existing pipe Po to be constructed. The pipe cutting jig 2A includes a wire attachment part 21 at both ends in the longitudinal direction and in the center in the radial direction. A jig connection portion 12 provided at the tip of the wire 11 is connected to this wire attachment portion 21 . In this embodiment, both are connected by screwing. Further, the pipe cutting jig 2A includes a blade mounting portion 22.

Here, the blade 4, which is an example of a processing means mounted on the blade mounting part 22, will be explained. This blade 4 has a flat plate shape and has a blade 41 at one end in the radial direction (upper end in the figure) for cutting the existing pipe Po when attached to the pipe cutting jig 2A. Further, as shown in FIGS. 3(a) to 3(c), a mounting hole 42 is formed in the center portion of the blade 4. That is, the cutter 4 as a processing means includes a mounting hole 42 in the center as a mounting part for the cutter mounting part 22 as a processing means mounting part, and blades 41 at both ends. The blades 41 at both ends are provided with their cutting edges facing in the same direction, specifically, toward one side in the width direction of the blade 4. In this embodiment, the first knife 4A (FIG. 3(b)) and the second knife 4B (FIG. 3(c)) and a third cutter 4C (FIG. 3(d)). That is, the cutter 4 as a processing means has a plurality of types of processing members (in this embodiment, a first cutter 4A, a second cutter 4B, and a third cutter 4C) so that different processing can be performed on the existing pipe Po. include. Each of the blades 4A to 4C is mounted on the blade mounting section 22 such that the higher side of the blade 41 is located at the movement source of the blade mounting section 22, and the lower side is located at the movement destination of the blade mounting section 22. The proper use of each of the blades 4A to 4C will be described later.

The blade mounting portion 22 has one blade through hole 221 extending in the radial direction. In the pipe cutting jig 2A, a screw hole 222 is provided so as to be perpendicular to the through hole 221 for the cutter, and a fixing screw (not shown) is attached to this screw hole 222, and the fixing screw is inserted into the attachment hole 42 of the cutter 4. By fitting the tip, the cutter 4 inserted into the cutter through hole 221 can be fixed by holding the cutter 4 with the tip of the fixing screw.

As shown in FIG. 4, the pipe diameter expanding jig 2B has a substantially conical shape with one longitudinal end reduced in diameter. The outer diameter of the large diameter side is larger than the inner diameter of the existing pipe Po. As a result, by passing the pipe diameter expansion jig 2B into the interior of the existing pipe Po (see Fig. 6(b)) that has undergone the existing pipe cutting process, with the small diameter side set as the front in the moving direction and the large diameter side set as the rear in the moving direction. , as shown in FIG. 6(d), the diameter of the divided portion D can be expanded. The pipe diameter expansion jig 2B includes a wire attachment part 23 that extends through the pipe in the longitudinal direction at the center in the radial direction. A jig connecting portion 12 provided at the tip of the wire 11 is connected to both ends of the wire mounting portion 23 . In this embodiment, like the pipe cutting jig 2A, both are connected by screwing.

The pipe insertion jig 3 is used while being fixed to the end of the new pipe Pn, as shown in FIG. 7(a). Fixing to the new pipe Pn may be done by making the part to be inserted into the new pipe Pn into a so-called "bamboo shoot" shape with a step formed in the axial direction, or by penetrating the side of the new pipe Pn. It may be fixed using a screw leading to the insertion jig 3, and the specific means is not particularly limited. The pipe insertion jig 3 includes a wire attachment part 31 at a portion exposed from the new pipe Pn when fixed to the end of the new pipe Pn. A jig connection portion 12 provided at the tip of the wire 11 is connected to this wire attachment portion 31 . In this embodiment, like the pipe cutting jig 2A and the pipe diameter expanding jig 2B, both are connected by screwing.

Next, we will explain the piping renewal method. The pipe renewal method of this embodiment includes a grooving process, an existing pipe cutting process, a diameter expansion process, and a new pipe insertion process. Hereinafter, one set of winches 1 will be described as a right winch 1R and a left winch 1L according to the arrangement shown in FIGS. 5 to 7. Note that "left and right" in the following is used for convenience of explanation, and the directions are not limited to those described below.

In the grooving process, a groove S along the pipe axis direction is formed on the inner circumferential surface of the existing pipe Po. Prior to the grooving process, as shown in FIG. 5(a), the wire 11 is passed through the existing pipe Po from the right winch 1R (not shown). At this time, the wire 11 is pushed from the right side in the figure to the left side by the operator's hand, and is taken out from the left end of the existing piping Po in the figure.

FIG. 5(b) shows the first stage of the grooving process. In the state shown in FIG. 5A, the tip of the wire 11 of the right winch 1R and the tip of the wire 11 of the left winch 1L are connected via the jig connection part 12 with the pipe cutting jig 2A. At this time, one first blade 4A is attached to the pipe cutting jig 2A. In this way, the blade 4 as a processing means is removable from the pipe cutting jig 2A, and when attached to the pipe cutting jig, the blade 41 is radially outward relative to the pipe cutting jig 2A. (one of them) stands out. In this state, the right winch 1R is operated to move the pipe cutting jig 2A from the left end of the existing pipe Po to the right end of the existing pipe Po so that the blade 41 of the first knife 4A comes into contact with the inner surface of the existing pipe Po. Here, as shown in FIG. 3(a), since both ends of the pipe cutting jig 2A in the longitudinal direction are reduced in diameter, the pipe cutting jig 2A can be easily inserted into the existing pipe Po. In addition, as described above, since the external dimensions of the large diameter part on the longitudinal center side of the pipe cutting jig 2A are smaller than the inner diameter of the existing pipe Po, the pipe cutting jig 2A is less susceptible to resistance from the existing pipe Po, and the existing pipe Po can be easily moved from the left end in the figure to the right end in the figure. As a result, as shown in FIG. 5(c), one groove S is formed in the inner peripheral portion of the existing pipe Po.

FIG. 5(d) shows the second stage of the grooving process. One second knife 4B is attached to the pipe cutting jig 2A. The direction of the second cutter 4B is reversed to that of the first cutter 4A in the first stage. In other words, the cutting tool 4 serving as a processing means is configured so that the processing direction of the pipe cutting jig 2A can be changed between facing toward one axial end of the pipe cutting jig 2A and facing toward the other axial end of the pipe cutting jig 2A. The amount of protrusion of the blade 41 in the radial direction of the second blade 4B is larger than that of the first blade 4A. In this state, the left winch 1L is operated to move the pipe cutting jig 2A from the right end in the figure of the existing pipe Po to the left end in the figure while aligning the blade 41 of the second cutter 4B along the groove S formed in the first step. As a result, the groove S becomes deeper as shown in FIG. 5(e). The grooving process is now complete. By cutting the existing pipe Po in the existing pipe cutting process described below with the groove S formed in the existing pipe Po through the above grooving process, cutting failures will not occur in the existing pipe cutting process, and the pipe axis direction Reliable cutting is possible. Furthermore, in the existing pipe cutting process described below, cutting along the groove S can reduce the resistance during cutting.

In the existing pipe cutting process, the existing pipe Po is cut in the radial direction and the pipe axis direction at one location in the circumferential direction where the groove S was formed in the grooving process. In this embodiment, this cutting is performed continuously in the tube axis direction. Note that the "radial direction" is not limited to the diametric direction passing through the axial center of the existing pipe Po, but may be any direction from the radially inner side to the radially outer side of the existing pipe Po. Therefore, the direction may be oblique to the diametrical direction.

FIG. 6(a) shows the existing pipe cutting process. One third knife 4C is attached to the pipe cutting jig 2A. The amount of protrusion of the blade 41 in the radial direction of the third blade 4C is larger than that of the second blade 4B. In this state, operate the right winch 1R and move the pipe cutting jig 2A from the left end of the existing pipe Po while aligning the blade 41 of the third cutter 4C along the groove S that has become deeper through the second stage of the grooving process. Move it to the right end in the illustration. As a result, as shown in FIG. 6(b), a divided portion D is formed, and the existing pipe Po has a radial cross-section having a "C" shape.

FIG. 6(c) shows the diameter expansion process. After removing the pipe cutting jig 2A, the tip of the wire 11 of the right winch 1R and the tip of the wire 11 of the left winch 1L are connected via the jig connection part 12 with the pipe diameter expanding jig 2B. The pipe diameter expanding jig 2B has a small diameter portion located on the left side of the drawing and a large diameter portion located on the right side of the drawing. In this state, the left winch 1L is operated to move the pipe diameter expansion jig 2B from the right end in the figure of the existing pipe Po to the left end in the figure. As a result, the divided portion D is deformed to expand as shown in FIG. 6(d). Note that this deformation is performed within the internal space of the protective material G.

In the new pipe insertion process, the new pipe Pn is passed through the protective material G and the inside of the existing pipe Po whose diameter has been expanded by the diameter expansion process, while aligning the new pipe Pn along the inner peripheral surface of the existing pipe Po. First, a new pipe Pn is prepared on the left side of the protective material G in the figure. A pipe insertion jig 3 is fixed to the right end of the new pipe Pn, and the tip of the wire 11 is connected to the pipe insertion jig 3 via a jig connection part 12. Note that the left winch 1L and its wire 11 are not used at this stage. Then, as shown in FIG. 7A, by operating the right winch 1R and pulling the new pipe Pn, the new pipe Pn is passed through the inside of the protective material G and the existing pipe Po. By passing the new pipe Pn through the protective material G and the existing pipe Po by pulling, it is more likely to get caught even in bent parts of the protective material G and the existing pipe Po, compared to passing the new pipe Pn by pushing. It is possible to pass the new pipe Pn while suppressing the damage. FIGS. 7(b) and 7(c) show the state in which the pipe insertion jig 3 is removed from the new pipe Pn. This completes the piping update, and then connects both ends to the water heater and faucet to complete the work.

In this embodiment, the outer diameter of the new pipe Pn is the same as or slightly larger than the inner diameter of the existing pipe Po. Therefore, in the new pipe insertion process, the new pipe Pn is inserted into the existing pipe Po while pushing the existing pipe Po, which has a "C"-shaped radial cross section , outwardly. Here, since the protective material G is made of a flexible material (for example, foamed resin, etc.) as described above, when the protective material G is pushed out, the inner diameter of the protective material G is radially outwardly moved by the existing pipe Po. Being pushed out. That is, when a new pipe Pn whose protective material G is made of a flexible material and whose outer diameter is the same as or slightly larger than the inner diameter of the existing pipe Po is inserted into the existing pipe Po, the cut existing pipe Po is held by the protective material G. At the same time, when the new pipe Pn is pushed and expanded due to insertion, the inner diameter of the flexible protective material G deforms and absorbs the spread, so the new pipe Pn is firmly guided by the protective material G and the existing pipe Po. , can be inserted smoothly. In addition, if the protective material G is flexible, the protective material will also be difficult to maintain when the new pipe Pn passes through the part that is fixed to the foundation B with a band (the part that is compressed and reduced in diameter by tightening the band). By deforming the inner diameter of G, insertion resistance can be alleviated.

In this manner, in the construction method of this embodiment, work can be performed at the ends of the existing piping Po and the protective material G exposed to the outside of the building C. For this reason, the work of replacing the existing pipe Po with the new pipe Pn is performed without removing the existing pipe Po and the protective material G from the installation target of the existing pipe Po (in this embodiment, the foundation B and floor material F of the building C). It can be done with In addition, the operation of each winch 1 and the insertion of the new pipe Pn into the existing pipe Po and the protective material G are performed outside the building C (specifically, in the closed space between the flooring F and the foundation B in the building C). This can be done externally). Therefore, there is no need to demolish building C, which can contribute to lower construction costs.

In addition, in the construction method of the present embodiment, two winches 1 capable of winding up the wire 11 as a cord are used, and one of the two winches, the right winch 1R as a winch on one side, is connected to the existing pipe Po and the right winch 1R. The left winch 1L, which is the other one of the two winches, is placed at one end (right end) of the protective material G, and the left winch 1L, which is the other one of the two winches, is placed between the existing pipe Po and the other end (left end) of the protective material G. part), and connect the piping processing jig 2 between the end of the wire 11 possessed by the right winch 1R and the end of the wire 11 possessed by the left winch 1L so as to be able to pass through the inside of the existing piping Po, By alternately operating the right winch 1R and the left winch 1L, the pipe processing jig 2 is reciprocated with respect to the existing pipe Po, and along with this reciprocating movement, the existing pipe cutting process and the diameter expanding process are performed. will be held. Therefore, preparations for inserting the new pipe Pn can be made efficiently.

As described above, according to the piping renewal method of this embodiment, the existing piping Po and the protective material G can be left fixed to the building C, and the diameter-enlarged existing piping Po can be used as a guide when laying the new piping Pn. . In addition, since there is no need to pull out the existing piping Po, the piping can be easily replaced without being affected by the installed shape of the piping.

Further, when updating the piping, it is unnecessary to dismantle the building C as much as possible, and there is no need to take special consideration when installing new piping. This "extraordinary consideration" means consideration beyond the minimum consideration of not forming sharp bends that could cause pipe breakage. In this way, by adopting the piping renewal method of this embodiment, the piping route can be set roughly when installing new piping, and it is also possible to make it possible to insert or remove the piping from the protective material G on site when installing new piping. Since it is not necessary to perform such tests, the number of man-hours required when installing new piping does not increase compared to the conventional method.

Further, in a pipe processing tool that includes a main body having a pipe cutting jig 2A and a cutter 4 as a processing means, and a jig connection part 12 that connects this main body to a wire 11, the pipe cutting jig 2A and a cutter 4 are provided. However, different machining can be performed depending on the case where the existing pipe Po is entered from one end in the axial direction and processed, and the case where the existing pipe Po is entered and processed from the other end in the axial direction. Specifically, changes can be made by changing the direction of the blade 41 at each stage of the grooving process or in the existing pipe cutting process, or by changing the type of each blade 4A to 4C to the pipe cutting jig 2A. By doing this, in the case of forward movement, one end side of the pipe cutting jig 2A enters from the inlet to the outlet of the existing pipe Po first, and in the case of forward movement, the other end side of the pipe cutting jig 2A enters first from the outlet to the inlet of the existing pipe Po. Since different processing can be performed depending on the case of double movement, the existing piping Po can be processed efficiently.

Although the embodiments of the present invention have been described above with reference to one example, the present invention is not limited to the embodiments described above, and various changes can be made without departing from the gist of the present invention.

For example, even if the protective material G has the function of heat insulation and heat retention, it does not have the function of heat insulation and heat retention and merely covers the pipe (existing pipe Po or new pipe Pn). You can. Further, the protective material G does not need to cover the entire pipe in the axial direction, and may cover a part of the pipe in the axial direction. Further, the protective material G may have a cut in the circumferential direction, such as a "C"-shaped cross section in the radial direction.

Further, although the winch 1 is used in the above embodiment, various devices capable of pulling cable-like materials such as wires and chains in the longitudinal direction may be used even if the device does not correspond to a winch (winding machine). I can do it.

In addition, in this embodiment, a pipe cutting jig 2A is provided between the end of the wire 11 possessed by the winch on one side (right winch 1R) and the end of the wire 11 possessed by the winch on the other side (left winch 1L). Although a case has been described in which the grooving process and the existing pipe cutting process are performed by connecting the pipes, the present invention is not limited thereto. For example, the pipe cutting jig 2A may be connected to the wire 11 of the right winch 1R and the wire 11 of the left winch 1L. This eliminates the need to use the jig connection part 12 attached to the tip of the wire 11, allowing efficient preparation. Also, one side winch is provided on one end side of one wire, the other side winch is provided on the other end side, and the pipe cutting jig 2A is connected to the middle part of the wire. A winch may be provided for each, and the wire may be passed through the pipe cutting jig 2A. In either case, the pipe cutting jig 2A is connected to the wire having the winch on one side and the wire having the winch on the other side so as to be able to pass through the inside of the existing pipe Po. Therefore, the pipe cutting jig 2A is moved back and forth using two winches, and the grooving process and the existing pipe cutting process are performed.

In addition, although the pipe cutting jig 2A has a substantially cylindrical shape in the above embodiment, there is no problem in movement in the pipe axis direction within the existing pipe Po, and it is possible to support a blade for cutting the existing pipe Po. If so, other shapes may be used. Further, the blade attached to the pipe cutting jig 2A may be either a fixed blade or a rotary blade. Further, the shape of the blade 41 is not particularly limited either. In the embodiment, the blade 41 can cut in one direction along the tube axis, but the blade 41 can cut in both directions along the tube axis. Thereby, the grooving process or the existing pipe cutting process can be performed without changing the orientation of the cutter 4 described above, so that the pipe renewal method of this embodiment can be performed efficiently.

Further, the number of stages and processing contents regarding the stages in the grooving process are not limited to those shown in the above embodiment (first stage to second stage), and can be changed in various ways. Furthermore, the grooving process can also be omitted. That is, in the existing pipe cutting process, the existing pipe Po can be cut without any prior processing on the inner circumferential surface. In this case, there is an advantage that a series of steps can be shortened by performing the existing pipe cutting step without performing any prior processing.

Moreover, in the embodiment, the diameter expansion step was performed prior to the new pipe insertion step. However, the present invention is not limited to this, and for example, the diameter expansion process may be performed simultaneously with the new pipe insertion process by arranging the pipe diameter expansion jig 2B in front of the pipe insertion jig 3 in the moving direction shown in FIG. 7(a). You can also do it.

1 Winch 11 Cable, wire 12 Jig connection part 2 Piping processing jig 2A Pipe cutting jig 2B Pipe diameter expansion jig 3 Pipe insertion jig 4 Knife C Building Po Existing pipe Pn New pipe
S groove G protective material

Claims (6)

A piping renewal method when replacing existing piping covered with a tubular protective material with new piping,
an existing pipe cutting step of cutting the existing pipe in the radial direction and the pipe axis direction at one point in the circumferential direction;
a diameter expansion step of expanding the diameter of the existing pipe;
Without removing the protective material and the existing piping from the object where the existing piping is installed, the new piping is placed inside the protective material and the existing piping while aligning it along the inner peripheral surface of the expanded diameter existing piping. The process of inserting new piping through the
It is a construction method that includes
Two winches capable of winding up the rope are used, and one of the two winches is placed at one end of the existing piping and the protection material, and the other one of the two winches is placed at one end of the existing piping and the protective material. one winch on the other side is arranged at the other end of the existing piping and the protective material,
A piping processing jig is connected between an end of the cable-shaped body of the one-side winch and an end of the cable-shaped body of the other-side winch so as to be able to pass through the inside of the existing piping,
By alternately operating the winch on one side and the winch on the other side, the piping processing jig is reciprocated with respect to the existing pipe, and along with this reciprocating movement, the process of cutting the existing pipe and the diameter expansion are performed. A piping renewal method characterized by the following steps : A piping renewal method when replacing existing piping covered with a tubular protective material with new piping,
an existing pipe cutting step of cutting the existing pipe in the radial direction and the pipe axial direction at one point in the circumferential direction without cutting the protective material covering the existing pipe;
a diameter expansion step of expanding the diameter of the existing pipe;
Without removing the uncut protective material and the existing piping from the installation target of the existing piping, the new piping is placed along the inner circumferential surface of the existing piping whose diameter has been expanded, and the protective material and the existing piping are removed. The process of inserting new piping inside the existing piping,
A piping renewal method characterized by including. prior to the existing pipe cutting step, including a grooving step of forming a groove along the pipe axis direction on the inner circumferential surface of the existing pipe,
The piping renewal method according to claim 2 , wherein in the existing piping cutting step, the existing piping is cut along the grooves formed in the grooving step. The piping renewal method according to claim 2 , wherein in the existing piping cutting step, the cutting is performed without performing any prior processing on the inner circumferential surface of the existing piping. The piping renewal according to any one of claims 2 to 4 , wherein the existing piping cutting step and the new piping insertion step are performed at an end where the existing piping and the protective material are exposed to the outside of the building. Construction method. Two winches capable of winding up the cord are used, and one of the two winches is placed at one end of the existing piping and the protection material, and the other one of the two winches is placed at one end of the existing piping and the protection material. one other side winch is arranged at the other side end of the existing piping and the protective material,
A piping processing jig is connected between an end of the cable-shaped body of the one-side winch and an end of the cable-shaped body of the other-side winch so as to be able to pass through the inside of the existing piping,
By alternately operating the winch on one side and the winch on the other side, the piping processing jig is reciprocated with respect to the existing pipe, and along with this reciprocating movement, the existing pipe cutting process and the diameter expansion process are performed. The piping renewal method according to any one of claims 2 to 5 , wherein the step of.