JP7353320B2 - Protective sleeves, pipes with protective sleeves, methods of laying pipes with protective sleeves - Google Patents

Description

The present invention relates to a cylindrical resin protective sleeve that covers the outer periphery of a metal tube, a tube with a protective sleeve, and a method for laying a tube with a protective sleeve.

Conventionally, when burying metal pipes such as ductile cast iron pipes underground, the outer periphery of the pipes was made of polyethylene to prevent corrosion and electrolytic corrosion by eliminating contact with corrosive soil and the influence of groundwater. A method is known in which the material is covered with a protective sleeve (polyethylene sleeve).

That is, as shown in FIGS. 17 and 18, when covering a pipe 101 such as a ductile cast iron pipe with a cylindrical protective sleeve 102, the pipe 101 is inserted into the protective sleeve 102, and the outer periphery of the pipe 101 is circumferentially covered. After folding the excess portion 103 that is loose and left over along the outer circumference of the tube 101 and temporarily fixing the excess portion 103 with adhesive tape or the like, wrap a rubber band 104 around the outer circumference of the protective sleeve 102 and tighten it. A protective sleeve 102 is secured to the tube 101.

Thereafter, the pipe 101 with the protective sleeve 102 is placed in a groove formed in the ground, the groove is filled with earth and sand, and the pipe 101 with the protective sleeve 102 is buried underground.

The protective sleeve 102 as described above is described, for example, in Patent Document 1 below.

JP2002-71086

However, in the above-mentioned conventional type, when the pipe 101 with the protective sleeve 102 is buried underground, even if stones, etc. contained in the earth and sand come into contact with the protective sleeve 102, a through hole is not generated in the protective sleeve 102. The protective sleeve 102 is made sufficiently thick. However, when the protective sleeve 102 becomes thick, the flexibility of the protective sleeve 102 decreases, and there is a problem that the workability when attaching the protective sleeve 102 to the pipe 101 decreases.

An object of the present invention is to provide a protective sleeve, a pipe with a protective sleeve, and a method for laying a pipe with a protective sleeve, which can make it difficult for through holes to occur and suppress deterioration in workability.

In order to achieve the above object, the first invention provides a cylindrical resin protective sleeve that covers the outer periphery of a metal pipe to prevent water from entering.
It has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
The sleeve body is a cylindrical sheet made of resin other than knitted or woven fabric.
At least one open end is formed with an end joint where the inner and outer sleeve bodies are joined to each other,
When the protective sleeve is not attached to the pipe, the boundary surface where the outer circumferential surface of the inner sleeve body and the inner circumferential surface of the outer sleeve body are in contact is formed along the circumferential direction of the sleeve body. It is.

According to this, the tube is inserted into the innermost sleeve body of the protective sleeve from one open end of the protective sleeve, and the outer periphery of the tube is covered with the protective sleeve. At this time, since the inner and outer sleeve bodies are joined to each other at the end joint of one open end of the protective sleeve, the inner circumference of the outer sleeve body and the outer circumference of the inner sleeve body may be mistakenly connected. This can prevent the product from being inserted between the two. This allows the tube to be inserted inside the innermost sleeve body and the protective sleeve to be correctly attached to the tube.

In addition, since the protective sleeve has an inside-outside multilayer structure consisting of multiple sleeve bodies that overlap inside and outside, when the protective sleeve is bent along the outer circumference of the pipe, the outer sleeve body and the inner sleeve body are located at the boundary between these sleeve bodies. It can bend while sliding relative to the surface in the circumferential direction. As a result, the protective sleeve can be bent more easily than a thicker protective sleeve with a single-layer (single-piece) structure rather than a multi-layered structure, and this suppresses the decline in workability when attaching the protective sleeve to a pipe. can do.

In addition, when a pipe with a protective sleeve attached is buried underground, no through-hole will be formed that penetrates the inside and outside of the protective sleeve unless holes are formed in all of the sleeve bodies that overlap inside and outside. hard.

The second invention is a cylindrical resin protective sleeve that covers the outer periphery of a metal pipe to prevent water from entering.
It has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
The sleeve body is a cylindrical sheet made of resin other than knitted or woven fabric.
Between both open ends, a longitudinal joint where the inner and outer sleeve bodies are joined is formed along the tube axis direction,
When the protective sleeve is not attached to the pipe, the boundary surface where the outer circumferential surface of the inner sleeve body and the inner circumferential surface of the outer sleeve body are in contact is formed along the circumferential direction of the sleeve body. It is.

According to this, when a protective sleeve is cut into a plurality of cut pieces and any of the cut pieces is used to cover the outer periphery of a deformed pipe, for example, the inner and outer sleeve bodies are connected to each other at the longitudinal joints of the cut pieces. Since they are joined, each sleeve body of the cut piece can be prevented from shifting in the tube axis direction.

In addition, since the protective sleeve has an inside-outside multilayer structure consisting of multiple sleeve bodies that overlap inside and outside, when the protective sleeve is bent along the outer circumference of the pipe, the outer sleeve body and the inner sleeve body are located at the boundary between these sleeve bodies. It can bend while sliding relative to the surface in the circumferential direction. As a result, the protective sleeve can be bent more easily than a thicker protective sleeve with a single-layer (single-piece) structure rather than a multi-layered structure, and this suppresses the decline in workability when attaching the protective sleeve to a pipe. can do.

In addition, when a pipe with a protective sleeve attached is buried underground, no through-hole will be formed that penetrates the inside and outside of the protective sleeve unless holes are formed in all of the sleeve bodies that overlap inside and outside. hard.

In the protective sleeve according to the third aspect of the present invention, a longitudinal joint where the inner and outer sleeve bodies are joined to each other is formed along the tube axis direction between both open ends.

In the protective sleeve according to the fourth aspect of the present invention, the inner and outer sleeve bodies are joined together by heat fusion.

According to this, the inner and outer sleeve bodies can be easily and reliably joined to each other.

The fifth invention is a pipe with a protective sleeve whose outer periphery is covered with a cylindrical resin protective sleeve and which is buried underground,
The protective sleeve has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
Between both open ends of the protective sleeve, a longitudinal joint where the inner and outer sleeve bodies are joined is formed along the tube axis direction,
A metal tube is inserted into the innermost sleeve body of the protective sleeve,
The excess portion of the protective sleeve that overlaps in the circumferential direction on the outer periphery of the tube is folded along the outer periphery of the tube,
A folding point is formed at the tip of the excess part,
The longitudinal joint portion is located at the folding point .

According to this, even if a tensile force that pulls the protective sleeve in the circumferential direction of the pipe acts on the protective sleeve, the longitudinal joint is hardly affected by the tensile force, and the outer sleeve body joined at the longitudinal joint This can prevent separation of the inner sleeve body and the inner sleeve body due to tensile force.

The sixth invention is a method for laying a pipe with a protective sleeve according to the fifth invention,
excavate the ground to form a trench,
A tube with a protective sleeve is placed in the groove,
The trench is backfilled with soil generated from excavation and the pipe is buried underground.

According to this, because the trenches are backfilled with soil generated from excavation and the pipes are buried underground, the installation work is much easier compared to backfilling the trenches with purchased soil instead of using soil. Cost can be reduced.

As described above, according to the present invention, the protective sleeve has an inner/outer multiplex structure consisting of a plurality of sleeve bodies overlapping inside and outside, so that when the protective sleeve is bent along the outer circumference of the pipe, the outer sleeve body and the inner sleeve body are and can be bent while sliding relative to each other in the circumferential direction at the interface between these sleeve bodies. As a result, the protective sleeve can be bent more easily than a thicker protective sleeve with a single-layer (single-piece) structure rather than a multi-layered structure, and this suppresses the decline in workability when attaching the protective sleeve to a pipe. can do.

In addition, when a pipe with a protective sleeve attached is buried underground, no through-hole will be formed that penetrates the inside and outside of the protective sleeve unless holes are formed in all of the sleeve bodies that overlap inside and outside. hard.

FIG. 2 is a diagram of a pipeline in which a tube with a protective sleeve is embedded in the first embodiment of the present invention. FIG. 3 is a sectional view of the joint portion of the pipe with a protective sleeve in the same embodiment. FIG. 3 is a diagram of the same tube with a protective sleeve. It is a perspective view of the protective sleeve in the same case. It is a sectional view of the protective sleeve in the same case. It is a figure of the display part of a protective sleeve in the same case. It is a cross-sectional view of the tube with a protective sleeve in the same figure, showing the state before folding up the excess portion of the protective sleeve. It is a cross-sectional view of the tube with a protective sleeve in the same figure, showing how the excess portion of the protective sleeve is folded along the outer periphery of the tube. It is a sectional view showing a method of installing a pipe with a protective sleeve in the same example, and shows how the pipe is arranged in a groove. It is a sectional view showing a method of laying a pipe with a protective sleeve in the same example, and shows how the pipe is buried underground. It is a figure which shows the manufacturing method of the protective sleeve in the 2nd Embodiment of this invention. It is a figure which shows the method of covering the outer periphery of a T-tube using the protective sleeve in the 3rd Embodiment of this invention. 13 is a view taken along the line XX in FIG. 12. FIG. It is a figure which shows the method of covering the outer periphery of a T-shaped tube using the same protective sleeve. It is a diagram in which the protective sleeve is cut into a plurality of cut pieces. It is a sectional view of the protective sleeve in the 4th embodiment of the present invention. 1 is a diagram of a conduit line in which a conventional protective sleeve-equipped pipe is embedded; FIG. FIG. 3 is a cross-sectional view of the same tube with a protective sleeve.

Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
In the first embodiment, as shown in FIG. 1, 1 is a conduit laid underground, and this conduit 1 connects a plurality of metal (for example, ductile cast iron) pipes 2. It is composed of The tube 2 has a socket 3 at one end and an insertion port 4 at the other end. As shown in FIG. 2, in the joint 5 between the pipes 2, the socket 4 of the other pipe 2 is inserted into the socket 3 of one pipe 2, and the inner periphery of the socket 3 and the outer periphery of the socket 4 are The gap between the two is sealed by a seal member 6.

The seal member 6 is a rubber ring, is provided between the inner periphery of the socket 3 and the outer periphery of the socket 4, and is pushed in the insertion direction A of the socket 4 by a press ring 7. The socket 3 has a flange 8 at its open end, and the press ring 7 is connected to the flange 8 via a plurality of T-shaped bolts 9 and nuts 10.

As shown in FIG. 3, the outer periphery of the tube 2 is covered with a cylindrical flexible protective sleeve 20. As shown in FIGS. 4 and 5, the protective sleeve 20 has an inner-outer double structure consisting of an outer sleeve body 21 that overlaps inside and outside and an inner sleeve body 22 provided inside the outer sleeve body 21. ing. The outer sleeve body 21 and the inner sleeve body 22 are each polyethylene sleeves made of flexible thin sheets made of transparent polyethylene (an example of resin) formed into cylindrical shapes.

Note that the above-mentioned transparent sheet includes not only a sheet that is completely transparent, but also a sheet that is transparent enough to allow the inner sleeve body 22 to be visually seen through the outer sleeve body 21.

At both open ends 24 and 25 of the protective sleeve 20, end joints 26 and 27, which are formed by joining the inner periphery of the outer sleeve body 21 and the outer periphery of the inner sleeve body 22 by heat fusion, extend over the entire circumference. It is formed.

Further, between both open ends 24 and 25 of the protective sleeve 20, a longitudinal joint 29 in which the outer sleeve body 21 and the inner sleeve body 22 are joined by heat fusion over the entire length is formed in the tube axis direction B. (longitudinal direction). Note that the longitudinal joint portion 29 is formed at one location in the circumferential direction C of the protective sleeve 20.

In this way, since the outer sleeve body 21 and the inner sleeve body 22 are heat-sealed at the end joints 26 and 27 and the longitudinal joint 29, respectively, the outer sleeve body 21 and the inner sleeve body The body 22 can be easily and reliably joined.

As shown in FIG. 6, display sections 31 and 32 displaying information about the tube 2 are printed on the outer circumference of the outer sleeve body 21 and the outer circumference of the inner sleeve body 22, respectively. The information about the tube 2 is, for example, the diameter of the tube 2, the name of the manufacturing company, etc.

The position of the display part 31 of the outer sleeve body 21 and the position of the display part 32 of the inner sleeve body 22 are shifted in the circumferential direction C, and the characters, marks, etc. displayed on the display part 31 and the display part 32 are different from each other. The letters, marks, etc. that are printed are oriented oppositely to each other in the circumferential direction C. The display portion 31 of the outer sleeve body 21 is visible from the outside, and the display portion 32 of the inner sleeve body 22 is visible from the outside through the outer sleeve body 21.

As shown in FIG. 6, the inner sleeve body 22 formed in a cylindrical shape is inserted into the outer sleeve body 21 formed in a cylindrical shape, and the outer sleeve body 22 is By heat-sealing the sleeve body 21 and the inner sleeve body 22, a protective sleeve 20 is manufactured as shown in FIG.

As shown in FIG. 7, the tube 2 is inserted into the sleeve body 22 (an example of the innermost sleeve body) inside the protective sleeve 20, and as shown in FIG. The excess portion 34 of the protective sleeve 20 left over is folded along the outer periphery of the tube 2. A folded portion 36 is formed at the tip of the surplus portion 34, and the longitudinal joint portion 29 is located at this folded portion 36.

As shown in FIGS. 2 and 3, a plurality of tightening members 38 for fixing the protective sleeve 20 to the tube 2 are wound around the outer periphery of the protective sleeve 20. As shown in FIGS. Note that the tightening member 38 is made of, for example, a rubber band or a binding belt.

A method of laying the pipe 2 whose outer periphery is covered with such a protective sleeve 20 and buried underground will be described below.

First, the tube 2 is inserted into the inner sleeve body 22 from either of the open ends 24, 25 of the protective sleeve 20, and as shown in FIG. Fold along. At this time, the display portion 31 (see FIG. 6) of the outer sleeve body 21 and the display portion 32 (see FIG. 6) of the inner sleeve body 22 are positioned in the surplus portion 34.

Thereafter, as shown in FIG. 3, the protective sleeve 20 is fixed to the tube 2 by wrapping the tightening member 38 around the outer periphery of the outer sleeve body 21. At this time, in preparation for joining the tubes 2 to each other, the socket end and the insertion end of the protective sleeve 20 are folded back to expose the socket 3 and insertion port 4 of the tube 2 to the outside of the protective sleeve 20. I'll keep it.

As shown in FIG. 9, the ground 41 at the place where the pipe 2 is laid is excavated to form a groove 42, the excess portion 34 of the protective sleeve 20 is placed at the top of the pipe (that is, facing upward), and the pipe 2 with the protective sleeve 20 is installed. It is disposed within the groove 42 . At this time, at least one of the display sections 31 and 32 located in the surplus portion 34 of the protective sleeve 20 is turned upward.

Thereafter, the insertion port 4 of the other tube 2 is inserted into the socket 3 of one tube 2, and the seal member 6, press ring 7, bolt 9, and nut 10 are attached to join the tubes 2 together. Thereafter, as shown in FIG. 2, the folded portions of the socket-side end and the insertion-side end of the protective sleeve 20 are returned to their original positions and placed over the outer periphery of the joint 5, and the tightening member 38 is placed around the outer periphery of the protective sleeve 20. The protective sleeve 20 is fixed to the joint part 5 by winding it. In the joint portion 5, the protective sleeve 20 of one pipe 2 and the protective sleeve 20 of the other pipe 2 overlap in the radial direction D.

Thereafter, as shown in FIG. 10, the trench 42 is backfilled with soil 44 generated by the excavation, and the pipe 2 is buried underground. Thereafter, the generated soil 44 above the pipe 2 is compacted using a rammer.

The operation of the above configuration will be explained below.

When the tube 2 is inserted into the inner sleeve body 22 from either of the two open ends 24, 25 of the protective sleeve 20, the outer sleeve is closed at both end joints 26, 27, respectively, as shown in FIG. Since the inner circumference of the body 21 and the outer circumference of the inner sleeve body 22 are joined over the entire circumference, it is possible to accidentally insert the tube 2 between the inner circumference of the outer sleeve body 21 and the outer circumference of the inner sleeve body 22. You can prevent this from happening. Thereby, the tube 2 can be inserted into the inside of the inner sleeve body 22 and the protective sleeve 20 can be correctly attached to the tube 2.

In addition, as shown in FIG. 5, since the protective sleeve 20 has an inner/outer double structure consisting of an outer sleeve body 21 and an inner sleeve body 22, when the protective sleeve 20 is bent along the outer periphery of the pipe 2, the outer The sleeve body 21 and the inner sleeve body 22 can bend while sliding relative to each other in the circumferential direction C at the boundary surface 45 between the sleeve bodies 21 and 22. As a result, the protective sleeve 20 can be easily bent compared to a thicker protective sleeve with a single layer (single body) structure, not a double layer structure, and this makes installation easier when attaching the protective sleeve 20 to the pipe 2. It is possible to suppress the decrease in

Further, when the pipe 2 with the protective sleeve 20 attached is buried underground, unless holes are formed in both the outer sleeve body 21 and the inner sleeve body 22, the through-holes penetrating inside and outside of the protective sleeve 20 will not be formed. Since this does not occur, through holes are less likely to occur.

Further, as shown in FIG. 4, the outer sleeve body 21 and the inner sleeve body 22 are heat-sealed at the end joints 26, 27 and the longitudinal joint 29, so that the outer sleeve body 21 and the inner sleeve body 22 are heat-sealed. and the inner sleeve body 22 can be easily and reliably joined.

In addition, as shown in FIG. 6, since the display parts 31 and 32 are present at two locations in the circumferential direction C of the protective sleeve 20, it is easy to hold the pipe with at least one of the display parts 31 and 32 facing upward. 2 can be buried.

Furthermore, as shown in FIG. 2, since the protective sleeve 20 is fixed to the pipe 2 by the tightening member 38, it is possible to prevent the protective sleeve 20 from shifting with respect to the pipe 2, and the buried pipe 2 and the protective sleeve It is possible to prevent groundwater from entering between the ground and the groundwater.

Furthermore, as shown in FIG. 8, since the longitudinal joint portion 29 is located at the folding point 36 of the surplus portion 34 of the protective sleeve 20, the tensile force F that pulls the protective sleeve 20 in the circumferential direction C of the tube 2 is applied to the protective sleeve 20. Even when acting on the sleeve 20, the longitudinal joint 29 is hardly affected by the tensile force F, and the outer sleeve body 21 and the inner sleeve body 22, which are joined at the longitudinal joint 29, are affected by the tensile force F. This can prevent separation due to

In addition, as shown in FIG. 10, in order to backfill the trench 42 with generated soil 44 generated by excavation and bury the pipe 2 underground, the trench 42 is filled with separately purchased soil instead of using the generated soil 44. Compared to the case of backfilling, the cost of construction work can be reduced.

In addition, since the pipe 2 is buried with the surplus portion 34 of the protective sleeve 20 as the top of the pipe, the impact when compacting the generated soil 44 above the pipe 2 using a rammer is absorbed by the surplus portion 34. The impact received by the tube 2 can be alleviated.

Further, since the outer sleeve body 21 and the inner sleeve body 22 can be made of the same material, size, shape, etc., the protective sleeve 20 can be manufactured easily.

(Second embodiment)
In the second embodiment, the protective sleeve 20 is manufactured by the following manufacturing method.

As shown in FIG. 11, a flat sheet member 51 made of polyethylene is rolled into a cylindrical shape and wound around the outside of the inner sleeve body 22 formed into a cylindrical shape. Then, by heat-sealing one end side 51a and the other end side 51b in the circumferential direction C of the sheet member 51 over the entire length, the cylindrical outer sleeve body 21 is formed outside the inner sleeve body 22, The outer sleeve body 21 and the inner sleeve body 22 form a longitudinal joint 29 in which the outer sleeve body 21 and the inner sleeve body 22 are joined by heat fusion in the tube axis direction B.

Thereafter, at both open ends 24 and 25 of the protective sleeve 20, the inner periphery of the outer sleeve body 21 and the outer periphery of the inner sleeve body 22 are joined by heat fusion over the entire circumference, and the end joining portion 26, form 27. In this way, the protective sleeve 20 is manufactured as shown in FIG. 4.

According to the method for manufacturing the protective sleeve 20 described above, the cylindrical outer sleeve body 21 is formed on the outside of the inner sleeve body 22 by a single heat-sealing operation, and the outer sleeve body 21 and the inner side are bonded together. Since the sleeve body 22 of the protective sleeve 20 can be joined in the tube axis direction B, the protective sleeve 20 can be manufactured easily.

(Third embodiment)
In the third embodiment, as shown in FIGS. 12 and 13, when the outer periphery of a T-shaped tube 60, which is an example of a deformed tube, is covered with the protective sleeve 20, a branch pipe 61 of the T-shaped tube 60 is inserted. An insertion hole 62 is formed in the protective sleeve 20. Furthermore, a straight cut portion 63 extending from one end of the protective sleeve 20 to the insertion hole 62 is formed.

Then, as shown in FIGS. 13 and 14, the T-tube 60 is inserted into the protective sleeve 20 from one open end 24 of the protective sleeve 20. At this time, the branch pipe 61 of the T-tube 60 is inserted into the insertion hole 62 from one open end 24 of the protective sleeve 20 through the cut portion 63. Thereafter, the cut portion 63 is sealed with adhesive tape or the like.

Next, as shown in FIG. 15, another protective sleeve 20 is cut into a plurality of cut pieces 65, 66, 67 in a direction perpendicular to the longitudinal direction. For example, when using a cut piece 66 intermediate between both open ends 24, 25 of the protective sleeve 20, a branch of the T-tube 60 is inserted into the cut piece 66, as shown in phantom in FIG. Insert 61.

At this time, since the outer sleeve body 21 and the inner sleeve body 22 are joined at the longitudinal joint portion 29 of the cut piece 66, the outer sleeve body 21 and the inner sleeve body 22 are connected in the tube axis direction. It is possible to prevent it from shifting to B.

Thereafter, the cut piece 66 and the protective sleeve 20 are adhered with adhesive tape, and the plurality of tightening members 38 are wrapped around the outer periphery of the protective sleeve 20 and the cut piece 66, and the protective sleeve 20 and the cut piece 66 are attached to the T-tube 60. Fixed to. Thereby, the T-tube 60 is covered by the protective sleeve 20 and the cut piece 66.

In the third embodiment, the intermediate cut piece 66 is used to cover the branch pipe 61 of the T-tube 60, but the cut piece 65 including one open end 24 or the other open end A cut piece 67 containing 25 may also be used.

In the third embodiment, one of the cut pieces 65, 66, and 67 obtained by cutting the protective sleeve 20 is used to cover the T-shaped tube 60. It may be used for pipes, etc., or it may be used for valves, etc.

(Fourth embodiment)
In the first to third embodiments described above, as shown in FIG. 5, the protective sleeve 20 has an inner and outer double structure consisting of an outer sleeve body 21 and an inner sleeve body 22. The present invention is not limited to such a double structure, but may have an inner/outer multiplexed structure consisting of a plurality of sleeve bodies overlapping inside and outside. In this case, the inner and outer overlapping sleeve bodies are heat-sealed to each other at the end joints 26, 27 and the longitudinal joint 29, respectively, and the tube 2 is inserted into the innermost sleeve body.

For example, as a fourth embodiment, as shown in FIG. 16, the protective sleeve 20 may have an inner and outer triple structure consisting of three sleeve bodies 21, 22, and 23, which overlap inside and outside. In this case, the tube 2 is inserted into the innermost sleeve body 23, and the sleeve bodies 21, 22, 23 are heat-sealed to each other at the end joints 26, 27 and the longitudinal joint 29, respectively. ing. According to this, the same functions and effects as those of the first to third embodiments can be obtained.

In each of the above embodiments, as shown in FIG. 4, at both open ends 24 and 25 of the protective sleeve 20, the outer sleeve body 21 and the inner sleeve body 22 are heat-sealed over the entire circumference. The protective sleeve 20 may have only one end joint 26 or only the other end joint 27 formed.

In addition, in the case of the protective sleeve 20 in which only one end joint 26 is formed as described above, when inserting the tube 2 into the inner sleeve body 22 from the one open end 24 of the protective sleeve 20, one end joint 26 is formed. Since the inner circumference of the outer sleeve body 21 and the outer circumference of the inner sleeve body 22 are joined over the entire circumference at the end joint portion 26, the inner circumference of the outer sleeve body 21 and the inner sleeve Insertion between the body 22 and the outer periphery of the body 22 can be prevented.

In the case of the protective sleeve 20 in which only the other end joint 27 is formed, when the tube 2 is inserted into the inner sleeve body 22 from the other open end 25 of the protective sleeve 20, the other end joint 27 At 27, the inner periphery of the outer sleeve body 21 and the outer periphery of the inner sleeve body 22 are joined over the entire circumference. This can prevent the product from being inserted between the

In each of the above embodiments, the outer sleeve body 21 and the inner sleeve body 22 are joined by heat fusion at the end joints 26 and 27 and the longitudinal joint 29 of the protective sleeve 20, respectively. The bonding is not limited to thermal bonding, and for example, bonding may be performed using thermal bonding, adhesive, or the like.

In each of the above embodiments, a ductile iron pipe is used as an example of the metal pipe 2, but other metal pipes may be used.

In each of the embodiments described above, as shown in FIG. The parts 31 and 32 may be used as a seal and attached to the outer sleeve body 21 and the inner sleeve body 22.

In each of the embodiments described above, the protective sleeve 20 is made of polyethylene, but it may be made of a resin other than polyethylene.

In each of the above embodiments, both the outer sleeve body 21 and the inner sleeve body 22 are transparent, but only the outer sleeve body 21 may be transparent.

2 Pipe 20 Protective sleeve 21, 22, 23 Sleeve body 24, 25 Open end portions 26, 27 End joint portion 29 Longitudinal joint portion 34 Surplus portion 41 Ground surface 42 Groove 44 Generated soil 45 Boundary surface B Pipe axial direction C Circumference direction

Claims (6)

A cylindrical resin protective sleeve that covers the outer periphery of a metal pipe to prevent water from entering,
It has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
The sleeve body is a cylindrical sheet made of resin other than knitted or woven fabric.
At least one open end is formed with an end joint where the inner and outer sleeve bodies are joined to each other,
When the protective sleeve is not attached to the pipe, a boundary surface where the outer peripheral surface of the inner sleeve body and the inner peripheral surface of the outer sleeve body are in contact is formed along the circumferential direction of the sleeve body. A protective sleeve featuring: A cylindrical resin protective sleeve that covers the outer periphery of a metal pipe to prevent water from entering,
It has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
The sleeve body is a cylindrical sheet made of resin other than knitted or woven fabric.
Between both open ends, a longitudinal joint where the inner and outer sleeve bodies are joined is formed along the tube axis direction,
When the protective sleeve is not attached to the pipe, a boundary surface where the outer peripheral surface of the inner sleeve body and the inner peripheral surface of the outer sleeve body are in contact is formed along the circumferential direction of the sleeve body. A protective sleeve featuring: 2. The protective sleeve according to claim 1, wherein a longitudinal joint is formed along the tube axis direction between the two open ends, where the inner and outer sleeve bodies are joined to each other. The protective sleeve according to any one of claims 1 to 3, wherein the inner and outer sleeve bodies are joined together by heat fusion. A pipe with a protective sleeve whose outer periphery is covered with a cylindrical resin protective sleeve and is buried underground,
The protective sleeve has an internal and external multiple structure consisting of multiple sleeve bodies that overlap inside and outside,
Between both open ends of the protective sleeve, a longitudinal joint where the inner and outer sleeve bodies are joined is formed along the tube axis direction,
A metal tube is inserted into the innermost sleeve body of the protective sleeve,
The excess portion of the protective sleeve that overlaps in the circumferential direction on the outer periphery of the tube is folded along the outer periphery of the tube,
A folding point is formed at the tip of the excess part,
A tube with a protective sleeve, characterized in that a longitudinal joint is located at the folding point . A method for laying a pipe with a protective sleeve according to claim 5, comprising:
excavate the ground to form a trench,
A tube with a protective sleeve is placed in the groove,
A method for laying a pipe with a protective sleeve, which comprises backfilling a trench with soil generated by excavation and burying the pipe underground.

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