JP2018048690A - Pipe conduit reclamation method - Google Patents

Abstract

CONSTITUTION: This pipe conduit reclamation method is carried out in such a way that at first a plurality of long-sized belt-like synthetic resin protection sheets 14 wound in a round form are prepared and arranged at one end part of an existing pipe line 30. Then, each of the protection sheets is made into an arc shape by curving and winding both end parts in a width direction while the plurality of protection sheets are being drawn out, these plurality of arc-shaped protection sheets are combined to each other to form a substantial cylindrical-shaped sheet cylinder 16. Then, the sheet cylinder is drawn into the existing pipe line passage while forming it and laid and a new installing pipe is inserted into the sheet cylinder.EFFECT: The sheet cylinder can be appropriately laid even in the case that a bore diameter of reclamation existing pipe line is large.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pipeline rehabilitation method, and more particularly to a pipeline rehabilitation method in which a new pipe is laid after a substantially cylindrical protective sheet is laid in an existing pipeline.

  An example of a conventional pipe line rehabilitation method is disclosed in Patent Document 1. In the technique of Patent Document 1, when rehabilitating an existing pipeline, first, a belt-shaped protective sheet is inserted into the existing pipeline while forming a substantially cylindrical shape, and the protective sheet (sheet cylinder) is inserted into the existing pipeline. Laying. And by inserting a new synthetic resin pipe into the protective sheet laid in the existing pipe line, the new pipe can be prevented from coming into contact with the protrusions on the inner peripheral surface of the existing pipe line and damaging it. ing.

JP 2012-251591 A

  There is a desire to expand the application of the pipeline rehabilitation method (sheet PIP method) as in Patent Document 1 using a protective sheet to existing pipelines having a large diameter.

  Here, in the technique of Patent Document 1, since a single protective sheet is rolled up to form a sheet cylinder, a protective sheet having a large width is required when applied to an existing pipeline having a large diameter. For example, when a new pipe having a diameter of 300 mm is laid in an existing pipeline having a diameter of 400 mm, a protective sheet having a width of about 1400 mm is required. However, a protective sheet having a large width is expensive to manufacture and is inconvenient to handle because it increases the weight.

  Therefore, the main object of the present invention is to provide a novel pipeline rehabilitation method.

  Another object of the present invention is to provide a substantially cylindrical protective sheet (sheet cylinder) that can be appropriately laid in an existing pipeline while suppressing construction costs even when the diameter of the existing pipeline to be rehabilitated is large. It is to provide a rehabilitation method.

  The first invention is a pipeline rehabilitation method for constructing a rehabilitation pipeline in an existing pipeline, and (a) a plurality of protective sheets made of a long strip-shaped synthetic resin wound in a roll shape are prepared, A step of installing the plurality of protective sheets on the one end side of the existing pipe line; (b) bending the plurality of protective sheets installed in step (a) so as to involve both ends in the width direction of the protective sheet; Thus, each of the protective sheets is formed into an arc shape in a state where a tension is applied to restore in the diameter increasing direction, and a plurality of arc-shaped protective sheets are combined to form a substantially cylindrical sheet cylinder. (C) a step of laying the sheet cylinder in the existing pipeline by drawing the sheet cylinder molded in step (b) into the existing pipeline using a sheet insertion jig; and (d) step ( ) In a sheet cylinder that is laid in the existing pipe line and has a substantially cylindrical shape without sagging inward due to the tension in the diameter increasing direction acting on each of the plurality of arc-shaped protective sheets. A pipeline rehabilitation method including a step of inserting a tube.

  In the pipeline rehabilitation method according to the first invention, first, in step (a), a plurality of protective sheets wound in a roll are prepared, and the plurality of protective sheets are provided on one end side of the existing pipeline. Installed in vertical shafts. Next, in step (b), each of the protection sheets is formed into an arc shape by curving so as to wind both ends in the width direction of the protection sheet while simultaneously pulling out the plurality of protection sheets. At this time, each of the protective sheets is in a state in which a tension to restore in the diameter expansion direction is acting. Then, a substantially cylindrical sheet cylinder is formed by combining the plurality of arc-shaped protective sheets. Subsequently, in step (c), the sheet cylinder is drawn into the existing pipeline using the sheet insertion jig, and the sheet cylinder is laid in the existing pipeline. In step (d), the new pipe is inserted into the sheet cylinder laid in the existing pipe line. At this time, the sheet cylinder is maintained in a substantially cylindrical shape without sagging inward by the tension in the diameter increasing direction acting on each of the plurality of arc-shaped protective sheets.

  In such 1st invention, since a sheet | seat cylinder is shape | molded combining a some protective sheet, the width | variety of the protective sheet to be used can be made small. That is, since it is not necessary to use a protective sheet having a large width, it is possible to suppress the manufacturing cost of the protective sheet and to prevent the protective sheet from becoming heavy. Furthermore, if a protective sheet with a large width is used, it may be necessary to increase the width of the shaft provided at one end of the existing pipe line, or the protective sheet may be damaged due to contact with the side wall of the shaft. However, such a problem can be solved by using a protective sheet having a small width.

  According to 1st invention, even when the diameter of the existing pipeline to rehabilitate is large, a sheet | seat cylinder can be appropriately laid in the existing pipeline, suppressing construction cost.

  The second invention is dependent on the first invention, and in step (b), at the time of forming the sheet tube, at least one of the end portions of the adjacent protective sheets is overlapped.

  The third invention is dependent on the first or second invention, and in the step (b), when the sheet tube is formed, all the end portions of the adjacent protective sheets are overlapped with each other.

  The fourth invention is dependent on any one of the first to third inventions, and in step (a), two protective sheets are prepared, the two protective sheets are arranged in the vertical direction, and the shaft is aligned. It is installed to extend in the lateral direction.

  According to the fourth invention, the protective sheet can be easily installed, and the operation of forming the sheet cylinder while pulling out the protective sheet is facilitated.

  The fifth invention is dependent on any one of the first to fourth inventions, and when the sheet tube is formed in step (b), the overlap margin between the ends of the adjacent protective sheets is a circle of the sheet tube. It is set to a size equal to or less than a quarter of the circumference.

  According to the fifth invention, even when the diameter of the sheet cylinder is large, it is possible to prevent the end portion of the protective sheet from drooping inward.

  The sixth invention is dependent on any one of the first to fifth inventions, and when forming the sheet tube in step (b), the overlap margin between the ends of the adjacent protective sheets is a circle of the sheet tube. The size is set to 1/32 or more of the circumference.

  According to the sixth aspect of the present invention, it is possible to prevent these overlapping portions from being detached when the sheet cylinder is inserted into the existing pipeline.

  According to this invention, even when the diameter of the existing pipeline is large, the seat tube can be appropriately laid in the existing pipeline while suppressing the construction cost.

  The above object, other objects, features, and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

It is an illustration figure which shows a mode that the existing pipe line was renovated by the pipe line renovation construction method which is one Example of this invention. It is an illustration figure which shows the new installation pipe used for a pipeline rehabilitation method. It is an illustration figure which shows the elongate belt-shaped protective sheet used for a pipe line renovation construction method. It is an illustration figure which shows a mode that a pulling wire is drawn in in an existing pipe line. It is an illustration figure which shows a mode that a conduction | electrical_connection pipe is inserted in the existing pipe line, and a conduction check operation | work is performed. It is an illustration figure which shows a conducting tube, Comprising: (a) is a top view of a conducting tube, (b) is a front view of a conducting tube. It is an illustration figure which shows a mode that the protection sheet and the sheet | seat cylinder formation jig | tool were installed in the starting shaft. It is an illustration figure which shows a mode that the protective sheet installed in the starting shaft was seen from the existing pipeline side. It is an illustration figure which shows a sheet | seat tube forming jig, Comprising: (a) is sectional drawing of a sheet tube forming jig, (b) is the external view seen from the one end side of a sheet tube forming jig. It is an illustration figure which shows a mode that a sheet | seat cylinder is inserted in the existing pipe line. It is an illustration figure which expands and shows the mode of the head part of the sheet | seat cylinder in FIG. It is an illustration figure which shows a leading head, Comprising: (a) is a top view of a leading head, (b) is a front view of a leading head. It is an illustration figure which shows a mode that a sheet | seat cylinder is shape | molded by two long strip | belt-shaped protection sheets, and is inserted in the existing pipe line. It is an illustration figure for demonstrating the overlap margin in a sheet | seat cylinder. It is an illustration figure which shows a mode that a lubricant is apply | coated within a sheet | seat cylinder. It is an illustration figure which shows a mode that a newly installed pipe | tube is inserted in a sheet | seat cylinder. It is an illustration figure which expands and shows the mode of the head part of the new installation pipe | tube in FIG.

  Referring to FIG. 1, a pipe rehabilitation method according to an embodiment of the present invention updates and rehabilitates an existing pipe line 30 by inserting a new pipe (rehabilitated pipe) 10 into the existing pipe line 30. It is. In this pipeline rehabilitation method, the long tube-shaped protective sheet 14 is used to insert the new tube 10 into the sheet tube 16 after it is inserted into the existing tube 30 while forming the sheet tube 16. As a result, the insertion resistance of the new pipe 10 is reduced, and damage to the new pipe 10 due to contact with the inner surface protrusions of the existing pipe line 30 is prevented. As will be described in detail later, the pipe line rehabilitation method of this embodiment is characterized in that the sheet cylinder 16 is formed using two protective sheets 14.

  In addition, the material of the existing pipeline 30 to rehabilitate, a use, a diameter, etc. are not specifically limited. The pipe line rehabilitation method according to the present invention can be applied to the rehabilitation of various existing pipe lines 30 such as reinforced concrete pipes, ceramic pipes, cast iron pipes, steel pipes and synthetic resin pipes, and can be used for water and sewage, gas, communication cable protection or electric power. The present invention can be applied to rehabilitation of the existing pipeline 30 for uses such as cable protection. However, the pipe line rehabilitation method according to the present invention is suitably used for rehabilitation of the existing pipe line 30 having a diameter of 300 to 500 mm.

  Moreover, in the following description, the existing pipe line 30 is assumed to be a cast water water pipe. The description will be made assuming that the diameter of the existing pipe line 30 is 400 mm, for example, and the pipe length (the length of one section to be rehabilitated) is, for example, 100 m.

  As shown in FIG. 2, the new pipe 10 forms a new rehabilitation pipe line in the existing pipe line 30. In this embodiment, the pipe pipe 12 formed of a polyolefin-based synthetic resin is connected. Consists of. Specifically, the pipe member 12 is made of polyethylene and is formed into a cylindrical shape by extrusion molding. The diameter of the tube member 12 is 300 mm (outer diameter 355 mm), for example, and the tube length is 5 m, for example. In this embodiment, the new pipe 10 having a necessary length is formed by butting the end faces of the pipe member 12 together and butting. However, as the new pipe 10, a long pipe wound around a drum or the like can be used. In addition, the diameter of the new pipe 10 is not particularly limited as long as it has an outer diameter that can be inserted into the existing pipe line 30, and can be appropriately changed according to the application.

  As shown in FIG. 3, the protective sheet 14 is made of a synthetic resin such as polyethylene or polypropylene, and is formed in a long strip shape (rectangular flat plate shape) having flexibility and elasticity. Prior to insertion into the existing pipe line 30, the protective sheet 14 is wound into a roll shape by a holding member such as a drum (not shown) and held so as to be continuously drawn out.

  The thickness of the protective sheet 14 is 0.5-1.0 mm, for example. The length of the protective sheet 14 in the longitudinal direction is set to be longer than the pipe length of the existing pipeline 30 to be rehabilitated, and is 120 m, for example. Moreover, the width | variety of the protection sheet 14 has a predetermined overlap margin W (refer FIG. 14), and follows the inner peripheral surface of the existing pipe line 30 by combining the two protection sheets 14 so that it may mention later. The size is set such that the substantially cylindrical sheet cylinder 16 can be formed. In this embodiment, the sheet cylinder 16 is formed by combining two protective sheets 14 having a width of 750 mm. At this time, both ends of the adjacent protective sheets 14 have a predetermined overlap margin W. Overlapping state is assumed.

  Hereinafter, the pipe line rehabilitation method for rehabilitating the existing pipe line 30 will be specifically described with reference to FIGS. In this pipe rehabilitation method, first, a start shaft 32 is excavated on one end side of the rehabilitation section of the existing pipe line 30 (laying section of the new pipe 10), and a reaching shaft 34 is excavated on the other end side. Thus, both ends of the existing pipeline 30 are opened in the start shaft 32 and the arrival shaft 34, respectively. Thereafter, the inside of the existing pipe line 30 is appropriately washed. In this case, the lubricant may be applied to the inner peripheral surface of the existing pipeline 30 by passing a sponge or the like soaked with the lubricant into the existing pipeline 30. Moreover, it is preferable to remove large protrusions in the existing pipeline 30.

  In addition, various devices necessary for construction, pipes to be inserted, and the like are appropriately prepared (loaded in) in the vicinity of the start shaft 32 and the reach shaft 34. For example, a winch 52 for winding the pulling wire 40 is disposed on the end shaft 34 side which is the end point. On the other hand, the pipe member 12, the two protective sheets 14, the sheet tube forming jig 20, the butt fusion machine 80, and the like are carried into the start shaft 32 side that is the starting point.

  Next, as shown in FIG. 4, the pulling work of the pulling wire 40 is performed by using the line tool 36. As the wiring tool 36, for example, a conventionally known tool including a wiring rod 38 and the like may be used. When the pulling wire 40 is retracted, first, the through rod 38 is inserted from the open end (start side open end) 30a on the start shaft 32 side of the existing pipe line 30, and the tip of the through rod 38 is already installed. The connecting rod 38 is pushed in as it is until it reaches the opening end (arrival side opening end) 30b on the reaching shaft 34 side of the pipeline 30. When the tip of the connecting rod 38 reaches the reaching opening end 30 b of the existing conduit 30, the pulling wire 40 is attached to the tip of the connecting rod 38 there. Then, the wire rod 38 is pulled back, and the pulling wire 40 is pulled to the start side opening end 30 a of the existing pipe line 30.

  Subsequently, as shown in FIG. 5, the conduction confirmation work of the existing pipe line 30 is performed using the conduction pipe 42. As shown in FIG. 6, the conducting tube 42 includes a main body 44 formed in a substantially cylindrical shape whose one end in the axial direction is reduced in diameter (sharpened), and has a certain hardness such as steel. Formed by. The maximum outer diameter of the main body 44 is set to be smaller than the inner diameter of the existing pipe line 30 and larger than the outer diameter of the new pipe 10 (pipe member 12), and is, for example, 390 mm. Further, on both end faces in the axial direction of the main body 44, for example, eye bolts are attached to form connecting portions 46 and 48 for connecting the pulling wire 40 and the first pull-in rope 50 and the like.

  Returning to FIG. 5, when conducting the conduction check work, first, in the start shaft 32, the pulling wire 40 is connected to the connecting portion 46 on the front side of the conducting tube 42, and the connecting portion on the rear side of the conducting tube 42 is connected. A first pull-in rope 50 is connected to 48. Then, by winding the pulling wire 40 with the winch 52, the conducting pipe 42 is drawn into the existing pipe line 30 from the start side opening end 30 a.

  In this embodiment, “front” means the front in the insertion direction of the conducting tube 42, a leading head 56 and a leading conduit 74 described later, and “rear” means the opposite side. The same applies hereinafter.

  When the conduction pipe 42 reaches the reaching shaft 34 of the existing pipe line 30, the damage of the conduction pipe 42 is confirmed. If there is no noticeable damage to the conducting tube 42, it is determined that there is no problem even if the operation is continued, and the pulling wire 40 and the first pull-in rope 50 are removed from the connecting portions 46, 48 of the conducting tube 42. At this time, the first pull-in rope 50 is inserted into the existing pipeline 30. The conducting pipe 42 removed from the first pull-in rope 50 is transported to the start shaft 32 side through the ground.

  When the continuity confirmation operation is completed, the molded sheet cylinder 16 is inserted into the existing pipe line 30 and laid while the sheet cylinder 16 is molded using the two protective sheets 14. In this step, first, as shown in FIG. 7, the sheet tube forming jig 20 and the two protective sheets 14 wound in a roll shape are installed at a predetermined position of the start shaft 32.

  Specifically, the sheet tube forming jig 20 is installed at a position away from the start side opening end 30a of the existing pipe line 30 by a predetermined distance. As shown in FIG. 9, the sheet tube forming jig 20 is a jig for facilitating (assisting) the forming operation when the sheet tube 16 is formed by combining a plurality of protective sheets 14. It is made of a synthetic material such as hard vinyl chloride or a hard material such as metal. The sheet tube forming jig 20 includes a short tube-shaped jig body 22. The jig body 22 is formed in a tapered cylindrical shape having both ends opened to reduce the diameter from the one end 22a side toward the other end 22b side. Further, two rectangular plate-shaped jig fixing portions 24 having through holes 24 a are formed on the outer peripheral surface of the jig main body 22. The axial length of the jig body 22 is, for example, 200 mm, and the inner diameter of the one end 22a of the jig body 22 is, for example, 530 mm. The inner diameter of the other end 22b of the jig body 22 is set to be approximately the same as the outer diameter of the sheet cylinder 16 to be molded, and is, for example, 380 mm. As shown in FIG. 7, such a sheet tube forming jig 20 is installed such that the other end 22 b side having a small diameter faces the start side opening end 30 a of the existing pipe line 30.

  Further, as shown in FIGS. 7 and 8, two protective sheets 14 wound in a roll shape are rotatably set (can be pulled out) with respect to a predetermined position on the one end 18a side of the sheet tube forming jig 20. To do. In this embodiment, the two protective sheets 14 are arranged so that they are arranged in the vertical direction and the axis thereof extends in the lateral direction (that is, the width direction of the start shaft 32). For example, the support shaft 26 that supports the lower protective sheet 14 is locked to the upper edge portion of the start shaft 32, and the support shaft 26 that supports the upper protective sheet 14 stands on the upper edge portion of the start shaft 32. The upper end of the provided support member 28 may be locked. 7 and the like show a mode in which the two protective sheets 14 are arranged in the vertical direction, but when the protective sheets 14 are arranged in the vertical direction, they may be arranged shifted in the front-rear direction. That is, one protective sheet 14 may be disposed obliquely above the other protective sheet 14.

  When the installation work of the sheet tube forming jig 20 and the protective sheet 14 is completed, as shown in FIGS. 10 and 11, the existing pipe line is then made using the sheet tube forming jig 20 and the sheet insertion jig 54. The laying operation of the sheet cylinder 16 (protective sheet 14) in the interior 30 is performed.

  The sheet insertion jig 54 is a jig for drawing and inserting the sheet cylinder 16 into the existing pipe line 30. In this embodiment, the connection pipe 64 and the leading head 56 described later are connected to the connection fitting 64. It is comprised by connecting via. However, the specific configuration of the sheet insertion jig 54 can be appropriately changed. For example, the sheet cylinder 16 can be pulled in by the leading head 56 alone without using the conducting tube 42.

  As shown in FIG. 12, the leading head 56 includes a main body 58 formed in a substantially cylindrical shape with foamed styrene or the like. The outer diameter of the main body 58 is set to be approximately the same as the inner diameter of the sheet cylinder 16 to be molded, and is, for example, 380 mm. Further, on both end surfaces in the axial direction of the main body 58, for example, eye bolts are attached to form connection portions 60, 62 for connecting the connection fitting 64, the second pull-in rope 66, and the like.

  Returning to FIGS. 10 and 11, when laying the seat tube 16, first, in the start shaft 32, the first pull-in rope 50 is connected to the connecting portion 46 on the front side of the conducting pipe 42, The connecting portion 48 on the rear side of the conducting tube 42 and the connecting portion 60 on the front side of the leading head 56 are connected via a connecting fitting 64. Further, the second pull-in rope 66 is connected to the connecting portion 62 on the rear side of the leading head 56.

  Further, the leading end portions of the two protective sheets 14 are fixed around the outer peripheral surface of the main body 58 of the leading head 56. Specifically, the two protective sheets 14 are pulled out from the holding means, and are bent so as to be wound around both end portions in the width direction of the respective protective sheets 14, so that each of the protective sheets 14 is restored to the expanding direction. It is assumed that the arc shape is in a state where is acting. Next, both ends of the two arc-shaped protective sheets 14 are overlapped from above and below to form a substantially cylindrical shape, and the leading end portion of the substantially cylindrical protective sheet 14 is inserted into the sheet cylinder forming jig 20. To do. Then, the leading end portion of the protective sheet 14 that has come out in a substantially cylindrical shape from the other end 18 b side of the sheet tube forming jig 20, that is, the leading end portion of the sheet tube 16 is wound around the outer peripheral surface of the leading head 56, It is fixed by a fastening tool 68 such as a fastening band. At this time, the leading head 56 is connected to the conducting tube 42 so that the front end of the main body 58 is slightly lifted, and the leading end portion of the sheet cylinder 16 fixed on the outer peripheral surface of the leading head 56 is the existing tube. It is preferable not to contact the inner peripheral surface of the path 30 (see FIG. 11). Thereby, the front-end | tip part of the sheet | seat cylinder 16 contacts with protrusions, such as a rust hump, of the internal peripheral surface of the existing pipe line 30, and is prevented from fracture | rupture.

  Then, as shown in FIG. 10, the first pull-in rope 50 is wound by winding the pulling wire 40 connected to the first pull-in rope 50 with the winch 52, or by the manual operation of the worker arranged in the reaching shaft 34. As the two protective sheets 14 are pulled out simultaneously, the formed sheet cylinder 16 is drawn into the existing pipe line 30 from the start side opening end 30a.

  At this time, as shown in FIG. 13, each of the two protective sheets 14 fixed to the leading head 56 in a state where the leading end portions are combined so as to have a substantially cylindrical shape, By passing through the inside of the tool 20, both end portions in the width direction are wound around the center side and automatically curved into an arc shape, and both end portions of the two arc-shaped protective sheets 14 are automatically overlapped with each other. A substantially cylindrical sheet cylinder 16 is formed. At this time, since the jig body 22 of the sheet tube forming jig 20 is formed in a taper tube shape, the two protective sheets 14 passing through the sheet tube forming jig 20 are included in the jig body 22. As it goes along the peripheral surface toward the other end 22b side, it gradually curves, and the deformation (molding) from the two belt-like protective sheets 14 to the substantially cylindrical sheet cylinder 16 is performed smoothly. .

  Further, the sheet cylinder 16 is attached to the sheet cylinder 16 after passing through the sheet cylinder forming jig 20 by attaching an adhesive tape 70 or the like to the both ends of the protective sheet 14 at regular intervals in the axial direction. Temporarily fix so that the substantially cylindrical shape can be maintained.

  Here, with reference to FIG. 14, the overlap margin W when the end portions of the protective sheet 14 are overlapped to form the sheet cylinder 16, that is, the overlap margin W between the ends of the adjacent protective sheets 14 is the sheet. It is preferable to set the size to a quarter or less of the circumferential length of the cylinder 16 and to a size of 1/32 or more of the circumferential length of the sheet cylinder 16. . When the overlap margin W is larger than a quarter of the circumferential length of the sheet cylinder 16, there is a possibility that the end of the protective sheet 14 hangs inward when the sheet cylinder 16 having a large diameter is formed. Because. Further, when the overlap margin W is less than 1/32 of the circumferential length of the sheet cylinder 16, the overlap portion is removed and a gap is formed when the sheet cylinder 16 is inserted into the existing pipe line 30. It is because there is a possibility that it will end. According to the experiments by the present inventors, when the overlap margin W is not less than 1/32 of the circumferential length of the sheet cylinder 16, the sheet cylinder 16 is inserted into the existing pipe line 30. In this case, it is confirmed that even if the relative positions of the protective sheets 14 are slightly deviated from each other, these overlapping portions are difficult to come off.

  Further, considering that it is possible to surely prevent the overlapping portions of the protective sheets 14 from coming off, to avoid waste of the protective sheet 14 as much as possible, and to consider the ease of construction, the overlapping allowance W is the circumference of the sheet cylinder 16. It is more preferable to set the size to 2/32/32 of the length. In this embodiment, the widths of the two protective sheets 14 are set so that the overlap allowance W is 3/3 of the circumferential length of the sheet cylinder 16 which is the optimum value.

  Returning to FIG. 10, the sheet cylinder 16 formed and held in a substantially cylindrical shape in the starting shaft 32 is sequentially drawn into the existing pipe line 30 thereafter. When the leading end portion of the sheet tube 16 reaches the reaching shaft 34 of the existing pipe line 30, the first pull-in rope 50 and the leading head 56 are removed from the conducting tube 42, and the sheet tube 16 and the second pull-in are removed from the leading head 56. Remove the rope 66. Thereafter, both ends of the seat tube 16 are fixed outside the start side opening end 30a and the arrival side opening end 30b. Thereby, the sheet cylinder 16 is laid over the entire length of the existing pipeline 30, and the laying operation of the sheet cylinder 16 (protective sheet 14) is completed. The sheet cylinder 16 laid in this manner is maintained in its substantially cylindrical shape without sagging inward by the tension in the diameter increasing direction acting on each of the arc-shaped protective sheets 14. Therefore, the laying work of the new pipe 10 described later becomes easy.

  When the laying operation of the sheet cylinder 16 is completed, subsequently, as shown in FIG. 15, an operation of applying a lubricant to the inner peripheral surface of the sheet cylinder 16 is performed in order to reduce resistance when the new tube 10 to be described later is inserted. Do. Specifically, first, the second pull-in rope 66 and the pulling wire 40 are connected to the reach shaft 34, and a sponge 72 soaked with a lubricant such as silicon oil is attached in the vicinity of the connecting portion. As the sponge 72, a conventionally known one may be used, but the size of the sponge 72 can be set to a size that matches the inner diameter of the sheet cylinder 16, and a lubricant can be applied to the entire inner peripheral surface of the sheet cylinder 16. It is good to do so.

  Then, for example, by pulling the second pull-in rope 66 manually by an operator deployed in the start shaft 32, the sponge 72 is pulled into the seat tube 16 from the arrival side opening end 30b side, and the inside of the seat tube 16 Apply lubricant to the circumference. Thereafter, when the sponge 72 reaches the start-side opening end 30a, the sponge 72 is detached from the second pull-in rope 66 and the pull wire 40, and the connection between the second pull-in rope 66 and the pull wire 40 is released. Thereby, the lubricant is applied to the entire inner peripheral surface of the sheet cylinder 16. At this time, the pulling wire 40 is pulled to the start shaft 32 side.

  When the operation of applying the lubricant to the inner peripheral surface of the sheet cylinder 16 is completed, the new pipe 10 is subsequently laid in the sheet cylinder 16 using the leading conduit 74 as shown in FIGS. 16 and 17.

  The front conduit 74 includes a main body 76 formed in a cylindrical shape whose one end is sealed with a synthetic resin. In this embodiment, the main body 76 includes a polyethylene pipe 76a and a cap 76b that seals one end thereof, and the polyethylene pipe 76a and the cap 76b are joined by butt fusion. The diameter of the polyethylene pipe 76a is set to a diameter almost equal to that of the new pipe 10 (pipe member 12), and is, for example, 300 mm. The cap 76b is formed with a connecting portion 78 for connecting the pulling wire 40, for example, by attaching an eyebolt.

  When laying the new pipe 10, first, the pulling wire 40 is connected to the connecting portion 78 of the leading conduit 74 in the start shaft 32. The front end face of the first pipe member 12 is abutted against the rear end face of the front conduit 74, and these are joined by butt fusion using the butt fusion machine 80. Then, the leading wire 74 and the first pipe member 12 are drawn into the seat tube 16, that is, the existing pipe line 30 by winding the pulling wire 40 with the winch 52.

  When the leading conduit 74 and the first pipe member 12 are drawn into the existing pipe line 30, the front end face of the second pipe member 12 is abutted against the rear end face of the first pipe member 12, and the butt fusion machine 80. These are joined by butt fusion. Then, the newly joined second pipe member 12 is drawn into the existing pipe line 30 by winding the pulling wire 40 with the winch 52. When the tube members 12 are joined to each other by butt fusion, the joined portion swells on the outer peripheral surface and a bead (not shown) is formed. Therefore, the bead is removed to smooth the joined portion. Good.

  Thereafter, such operations are sequentially repeated, and the new tube 10 is drawn into the seat tube 16. At this time, the new pipe 10 advances in the sheet cylinder 16, that is, the sheet cylinder 16 is interposed between the new pipe 10 and the existing pipe line 30, so that the new pipe 10 is brought into contact with the inner surface projection of the existing pipe line 30. Damage to the new pipe 10 is prevented. Further, the insertion resistance of the new pipe 10 is reduced.

  When the front end of the new pipe 10 reaches the reach shaft 34, the pulling wire 40 is removed from the connecting portion 78 of the front pipe 74, and the front pipe 74 is cut from the new pipe 10 to perform the laying operation of the new pipe 10. finish.

  As described above, according to this embodiment, since the sheet cylinder 16 is formed by combining the two protective sheets 14, the width of the protective sheet 14 to be used can be reduced. That is, since it is not necessary to use the protective sheet 14 having a large width, the manufacturing cost of the protective sheet 14 can be suppressed, and the protective sheet 14 can be prevented from becoming heavy.

  In addition, when the protective sheet 14 having a large width is used, the width of the start shaft 32 needs to be increased accordingly, or the protective sheet 14 may come into contact with the side wall of the start shaft 32 and be damaged. However, such a problem can be solved by using the protective sheet 14 having a small width.

  Furthermore, the thing with the same width as the protective sheet 14 currently used with the existing pipe line 30 with a small diameter can also be used with respect to the existing pipe line 30 with a big diameter. That is, since the diameter range of the existing pipe line 30 that can be handled by the protective sheet 14 having one width is widened, the stock of the protective sheet 14 can be reduced, and the cost can be reduced.

  Therefore, according to this embodiment, even when the diameter of the existing pipeline 30 is large, the sheet cylinder 16 (substantially cylindrical protective sheet 14) can be appropriately laid in the existing pipeline 30 while suppressing the construction cost. .

  Further, according to this embodiment, the two protective sheets 14 are arranged so that the two protective sheets 14 are arranged in the vertical direction and the shaft extends in the horizontal direction, so that the protective sheet 14 can be easily installed. The operation | work which shape | molds the sheet | seat cylinder 16 while pulling out becomes easy.

  In the above-described embodiment, the two protective sheets 14 having the same width are used. However, the widths of the protective sheets 14 to be used may be different from each other. In this case, for example, the protective sheet 14 having a larger width may be disposed on the lower side, and the protective sheet 14 having a smaller width may be disposed on the upper side.

  Moreover, in the above-mentioned Example, although the sheet | seat cylinder 16 was shape | molded using the two protective sheets 14, the sheet | seat cylinder 16 can also be shape | molded using three or more protective sheets 14. FIG.

  Furthermore, in the above-described embodiment, the protective sheet 14 is installed (horizontal placement) so that the shaft extends in the horizontal direction, but may be installed (vertical placement) so that the shaft extends in the vertical direction. May be installed (tilted) so as to extend in an oblique direction. However, since it is difficult to install vertically or obliquely, the protective sheet 14 is preferably placed horizontally.

  Furthermore, in the above-described embodiment, when the substantially cylindrical sheet tube 16 is formed, all the end portions of the adjacent protective sheets 14 are overlapped with each other. There may be a slight gap between the parts. That is, the “substantially cylindrical shape” referred to in the present invention includes not only the state in which the sheet cylinder 16 is completely closed in the circumferential direction, but also a part in the circumferential direction within the scope not changing the gist of the present invention. It also includes a state in which there is a gap. However, in order to appropriately reduce the insertion resistance of the new pipe 10 and to prevent damage to the new pipe 10, at least one of the end portions of the adjacent protective sheets 14 overlaps the sheet cylinder 16. It is preferable to be molded in a state, and it is more preferable that the ends of the adjacent protective sheets 14 are overlapped as in the above-described embodiment.

  In the above-described embodiment, the sheet tube forming jig 20 (jig main body 22) is formed in a tapered tube shape. However, the sheet tube forming jig 20 is not necessarily formed in a tapered tube shape. The shape can be changed as appropriate. Further, when the sheet tube 16 is formed by combining the protective sheet 14, it is not always necessary to use the sheet tube forming jig 20.

  Furthermore, in the above-described embodiment, in order to maintain the substantially cylindrical shape of the sheet cylinder 16, a fastener such as the adhesive tape 70 is used. However, the present invention is not limited to this. For example, a fastener such as a binding band can be used. Further, the shape of the sheet cylinder 16 may be held in a substantially cylindrical shape by using an adhesive or by welding (fusion). The restriction on the shape of the sheet cylinder 16 at this time does not need to be strong. For example, the restriction may be released when the new pipe 10 is laid in the sheet cylinder 16 or after laying.

  Furthermore, in the above-described embodiment, the sheet cylinder 16 is inserted from the start side opening end 30 a of the existing pipe line 30, but the sheet cylinder 16 is inserted from the arrival side opening end 30 b of the existing pipe line 30. Also good. That is, the insertion direction of the seat tube 16 and the insertion direction of the new tube 10 may be opposite.

  It should be noted that the specific numerical values such as the dimensions mentioned above are merely examples, and can be appropriately changed according to the needs of product specifications and the like.

DESCRIPTION OF SYMBOLS 10 ... Newly installed pipe 12 ... Pipe member 14 ... Protective sheet 16 ... Sheet cylinder 20 ... Sheet cylinder forming jig 30 ... Existing pipe line 32 ... Starting shaft 34 ... Arrival shaft 54 ... Sheet insertion jig

Claims (6)

It is a pipeline rehabilitation method for constructing a rehabilitation pipeline in an existing pipeline,
(A) A step of preparing a plurality of protective sheets made of a long strip-shaped synthetic resin wound in a roll shape, and installing the plurality of protective sheets on one end side of the existing pipe line,
(B) An attempt is made to restore each of the protective sheets in the diameter-enlarging direction by pulling out the plurality of protective sheets installed in the step (a) and curving them so as to involve both ends of the protective sheet in the width direction. A step of forming a substantially cylindrical sheet cylinder by combining the plurality of arc-shaped protective sheets into an arc shape in a state in which tension is applied,
(C) laying the sheet cylinder in the existing pipeline by drawing the sheet cylinder formed in the step (b) into the existing pipeline using a sheet insertion jig; and (d) ) In the step (c), a substantially cylindrical shape is maintained without sagging inward by applying tension in the diameter increasing direction to each of the plurality of arc-shaped protective sheets. A pipe line rehabilitation method comprising the step of inserting a new pipe into the sheet cylinder.   The pipe line rehabilitation method according to claim 1, wherein in the step (b), at the time of forming the sheet cylinder, at least one of the end portions of the adjacent protective sheets is overlapped.   The pipe line rehabilitation method according to claim 1 or 2, wherein in the step (b), when the sheet cylinder is formed, all of the end portions of the adjacent protective sheets are overlapped with each other.   In said step (a), two said protective sheets are prepared, these two protective sheets are arranged in the up-down direction, and the axis | shaft is installed so that a shaft may be extended in a horizontal direction. The pipeline rehabilitation method described in 1.   5. The method according to claim 2, wherein, in the step (b), an overlapping margin between the end portions of the adjacent protective sheets is set to a size equal to or less than a quarter of a circumferential length of the sheet tube. The pipe rehabilitation method described in Crab.   6. The method according to claim 2, wherein, in the step (b), the overlap margin between the end portions of the adjacent protective sheets is set to a size of 1/32 or more of the circumferential length of the sheet cylinder. The pipe rehabilitation method described in Crab.

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