JP2022116752A - Pipe joint structure - Google Patents

Abstract

To deal with various specifications of an opposite side pipe body easily in a pipe joint structure which connects a regeneration pipe covered by a liner pipe with another pipe body.SOLUTION: A pipe joint structure includes: an existing pipe 1; a liner pipe 2 including a cover part 2a which covers an inner surface of the existing pipe 1 and a liner protruding part 2b protruding from one end as seen in a pipe axis direction of the existing pipe 1 in a continuous manner; a guide member 3 disposed at the outer side of the liner protruding part 2b; a connection jig 4 including an inner part 4a which enters the inner side of the liner protruding part 2b and an outer part 4b protruding from the inner part 4a to one side in the pipe axis direction; an outer member 5 including a base part 5a which contacts with an outer surface 2c of the liner protruding part 2b; a taper part 12 which is provided in at least one of an outer surface 4c of the inner part 4a and an inner surface 5d of the outer member 5 and has a diameter expanding to the one side in the pipe axis direction; and fastening means 20 which draws the connection jig 4 and the outer member 5 in the pipe axis direction and fixes the connection jig 4, the liner protruding part 2b, and the outer member 5.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a pipe joint structure used for connecting an existing pipe whose inner surface is covered with a liner pipe and another opposite pipe.

Conventionally, when various pipes such as transmission and distribution pipes (hereinafter referred to as existing pipes) have deteriorated, insert a pipe made of a flexible material into the existing pipe and insert it into the inner surface of the existing pipe. Rehabilitation of the pipeline is performed by making it adhere closely. A tubular body that is brought into close contact with the inner surface of an existing pipe is called a liner pipe, and an existing pipe whose inner surface is covered with a liner pipe is called a rehabilitation pipe. The liner pipe is expanded by steam and compressed air, closely attached to the inner peripheral surface of the existing pipe, and then solidified by cooling to be integrated with the existing pipe. Also, the pipe end of the rehabilitating pipe is connected to the opposite pipe end of another pipe via a pipe joint. As a pipe joint structure of this kind, there are those described in Patent Documents 1 to 4, for example.

In the pipe joint structure of Patent Document 1, a pipe end water stop member that abuts, with a packing interposed, on the end face of the pipe end portion of the rehabilitating pipe whose inner surface is covered with a liner pipe, is provided, and the outer circumference of the pipe end portion of the rehabilitating pipe is provided. and the outer circumference of the pipe end of another pipe body facing it, and a joint ring is inserted between it, and the fitting surface is water-stopped with a wedge-shaped rubber ring.

In the pipe joint structure of Patent Document 2, rubber packings are arranged on the outer periphery of a pipe body and a liner pipe protruding from the pipe body in the pipe axial direction, and the rubber packings are used as a fixed flange pipe, a connecting flange pipe, and a seal flange. It is sandwiched between pipes and sealed. An extension flange pipe is connected to the seal flange pipe to extend the pipeline.

The pipe joint structure of Patent Literature 3 includes a pair of tubular bodies having flexible tubes in close contact with their inner peripheral surfaces, flanges provided at the ends of the tubular bodies, respectively, and pipe axially inward from the end faces of the flanges. It has a tapered inner peripheral surface that decreases in diameter and a connection pipe having both ends with tapered outer peripheral surfaces that are in close contact with the tapered inner peripheral surface. By fastening the facing collars with bolts and nuts, the ends of the flexible tube are pressed and held between the tapered inner peripheral surface and the tapered outer peripheral surface, thereby closing the gap between the flexible tube and the tubular body. maintains airtightness.

In the pipe joint structure of Patent Document 4, the liner pipe (lining hose) of the rehabilitated pipe protrudes outward in the pipe axial direction from the end of the rehabilitated pipe. A guide pipe is provided so as to straddle between the outer circumference of the end of the rehabilitating pipe and the outer circumference of the protruding lining hose. In the outer peripheral portion of the lining hose, the guide pipe has a tapered inner peripheral surface whose inner diameter increases with distance from the end of the rehabilitating pipe, and has a flange at its tip. A joint pipe is inserted into the inner periphery of the protruding lining hose, and the flange provided on the joint pipe and the flange of the guide pipe are fastened with bolts and nuts to form a rehabilitation pipe equipped with a liner pipe and a guide pipe, A fitting pipe is connected. In addition, a joint ring is fitted between the outer circumference of the joint pipe and the outer circumference of the pipe end portion of another pipe body opposed thereto, and the fitting surface is watertight with a wedge-shaped rubber ring.

Japanese Patent Application Laid-Open No. 2019-17808 Japanese Patent Application Laid-Open No. 2015-3470 (paragraph 0020 of the specification, see FIG. 3, etc.) Japanese Patent Application Laid-Open No. 5-272666 (paragraph 0023 of the specification, see FIG. 5, etc.) Japanese Patent Publication No. 2-29920 (see FIG. 2, etc.)

In the pipe joint structures of Patent Documents 1 to 4, in order to connect the rehabilitating pipe to another opposing pipe body, a plurality of constituent members corresponding to the diameter and type of pipe are employed. For this reason, there is a problem that many types of structural members must be prepared to correspond to variations in diameter and type of pipes to be connected. Preparing a large number of types of structural members is not preferable because it leads to an increase in cost, and it also leads to complication of work, so there is room for improvement.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a pipe joint structure for connecting a rehabilitating pipe covered with a liner pipe to another opposed pipe body, so that it can be easily adapted to pipe bodies of various specifications.

In order to solve the above problems, the present invention provides an existing pipe, a covering portion that covers the inner surface of the existing pipe, and a liner projecting portion that projects from one axial end of the existing pipe. a guide member disposed outside the liner protrusion; an inner portion that enters inside the liner protrusion; and an outer portion that protrudes from the inner portion in one direction in the tube axial direction. an outer member having a base portion in contact with the outer surface of the liner projecting portion; a tapered portion provided on at least one of the outer surface of the inner portion and the inner surface of the outer member and expanding in diameter in one direction in the pipe axial direction; A pipe joint structure is adopted that includes tightening means for pulling together the jig and the outer member in the direction of the pipe axis to fix the connection jig, the liner protrusion, and the outer member.

Here, the connection jig is provided with a diameter changing portion between the inner portion and the outer portion, and the diameter changing portion expands in one direction in the tube axial direction. can be done.

Here, it is possible to employ a configuration in which an annular seal member is provided between the outer surface of the inner portion and the inner surface of the liner protrusion.

Further, the guide member is an annular member having a cylindrical outer surface, and the outer surface of the guide member and the inner surface of the outer member are in sliding contact with each other before being fixed by the tightening means. A configuration in which movement of the outer member in the tube axis direction is guided can be employed.

In each of these aspects, the tightening means includes a first flange portion provided on the connecting jig and rising outward from the outer portion, and a second flange portion provided on the outer member and rising outward from the base portion. , a configuration including a bolt penetrating through the first flange portion and the second flange portion and a nut screwed into the bolt.

INDUSTRIAL APPLICABILITY According to the present invention, in a pipe joint structure for connecting a rehabilitating pipe covered with a liner pipe to another pipe, it becomes possible to easily adapt to various specifications of the other pipe.

1 is a vertical sectional view showing one embodiment of the present invention; II-II sectional view of FIG. Longitudinal sectional view showing another embodiment

An embodiment of the present invention will be described based on the drawings. This embodiment, as shown in FIG. A pipe joint structure 10 used to connect a pipe end portion p1 of another pipe body P facing the pipe end portion, and a pipe connection method using the pipe joint structure 10. FIG. In this embodiment, the material of the existing pipe 1 and the pipe body P is a mortar-lined pipe obtained by applying a mortar lining to the inner surface of a metal pipe, but pipe bodies made of other materials may be used. Applications of the existing pipe 1 include, for example, water supply pipes, sewage pipes, various transmission/distribution pipes for agricultural water, industrial water, etc., and fluid supply pipes for supplying various fluids.

The liner pipe 2 is continuously provided with a covering portion 2a covering the inner surface of the existing pipe 1 and a liner projecting portion 2b projecting from one end portion of the existing pipe 1 in the pipe axial direction. That is, the liner pipe 2 extends from the inside of the existing pipe 1 and protrudes from the end of the existing pipe 1 to the outside. The material of the liner tube 2 is, for example, a tube made of a resin such as thermosetting plastic or thermoplastic, or a flexible material such as rubber. A tube, which is the material of the liner pipe 2, is inserted into the existing pipe 1, the tube is expanded with steam and compressed air to adhere to the inner peripheral surface of the existing pipe 1, and then cooled and solidified to regenerate the pipe. . By covering the inner surface of the pipe with the expanded tube, the existing pipe 1 integrated with the liner pipe 2 becomes a rehabilitated pipe. This rehabilitation is often performed by cutting the old pipe 1 in a predetermined range and inserting a tube from the cut end of the existing pipe. FIG. 1 shows the vicinity of the end of the rehabilitated pipe (one end of the existing pipe 1 in the pipe axial direction).

The pipe joint structure 10 includes a guide member 3 disposed outside (radially outward) of the liner projecting portion 2b, an inner portion 4a entering the inside (radially inwardly) of the liner projecting portion 2b, and another tubular body P. A connecting jig 4 having an outer portion 4b serving as a connecting portion and an outer member 5 having a base portion 5a in contact with the outer surface 2c of the liner projecting portion 2b are provided. At least one of the outer surface 4c of the inner portion 4a and the inner surface 5d of the outer member 5 has a diameter that increases in one axial direction, i.e., as it moves away from the end of the existing pipe 1, and contacts the liner projecting portion 2b. A tapered portion 12 is provided. In this embodiment, tapered portions 12 are provided on both the outer surface 4c of the inner portion 4a and the inner surface 5d of the outer member 5 as the tapered portion 12, and the tapered portion 12 on the outer surface 4c of the inner portion 4a is formed on the liner protruding portion 2b. The tapered portion 12b of the inner surface 5d of the outer member 5 is the tapered portion 12b contacting the inner surface 2d, and the tapered portion 12a of the inner surface 5d is the tapered portion 12a contacting the outer surface 2c of the liner projecting portion 2b. Further, the pipe joint structure 10 includes a tightening means 20 that draws the connection jig 4 and the outer member 5 in the pipe axial direction to fix the connection jig 4, the liner protrusion 2b and the outer member 5 to each other.

The guide member 3 is composed of an annular member that covers the outer surface 2c of the liner protrusion 2b. If the guide member 3 is fitted around the outer periphery of the liner pipe 2 before the liner pipe 2 is expanded, workability of mounting is improved. It is preferable that the inner surface 3d of the guide member 3 is in close contact with the outer surface 2c of the liner projecting portion 2b when the guide member 3 is attached to the outer periphery of the liner tube 2 . In this embodiment, a cylindrical plate member is used as the guide member 3 . The outer surface 3c of the guide member 3 is a cylindrical surface, and the sliding contact between the outer surface 3c and the inner surface 5d of the outer member 5 functions as a guide ring. The guide member 3 also exhibits a function of protecting the liner tube 2 by covering the outer surface 2c of the liner projecting portion 2b. As a material for the guide member 3, metal or hard resin can be used. In this embodiment, stainless steel is used as the material of the guide member 3 . If the guide member 3 is made of a plate member, it is easy to cut the member on site to adjust the length.

The connecting jig 4 has an annular inner portion (inner core) 4a protruding toward the other side in the pipe axial direction so as to be inserted into the liner protruding portion 2b, and an annular outer portion 4b of the inner portion. It protrudes from 4a to one side in the tube axial direction. The outer portion 4b serves as a connecting portion to the pipe end portion p1 of another tubular body P which is opposed. Connection and fixation of the outer part 4b and another tubular body P are performed by a connection means 30, which will be described later. An inner surface 4 d at the tip of the inner portion 4 a is preferably a cylindrical surface having an axis that matches the axis of the existing pipe 1 . Moreover, it is desirable that the inner surface 4d of the tip of the inner portion 4a and the inner surface 2d of the covering portion 2a are smoothly connected with as few steps as possible and with as few bending points as possible.

The outer portion 4b is connected to the inner portion 4a and has a diameter changing portion 4e that expands toward one side in the pipe axial direction, and a diameter changing portion 4e that is connected to the diameter changing portion 4e and has a cylindrical shape toward the one side in the pipe axial direction. and an elongated cylindrical portion 4f. In this embodiment, the diameter changing portion 4e is formed of a tapered surface whose inner diameter changes continuously. A stepped surface may be used. By providing the diameter changing portion 4e, it is possible to correspond to various pipe diameters of the tubular body P by changing only the connection jig 4 to one having different specifications. Here, it is desirable that the inner surface of the cylindrical portion 4f be a cylindrical surface having an axial center that matches the tube axis of the tubular body P. As shown in FIG. Moreover, it is desirable that the connecting portion between the inner surface of the cylindrical portion 4f and the inner surface of the tubular body P has as few steps as possible and that the two are smoothly connected with few bending points. In the embodiment of FIG. 1, the position (range) of the diameter changing portion 4e in the tube axial direction is from the outer tapered portion 12b, which is the tapered portion 12 of the inner portion 4a, to the outer portion 4b. are placed. By overlapping the tapered portion 12 and the diameter changing portion 4e in the pipe axial direction in this way, it is possible to ensure a wide distance of the diameter changing portion 4e in the pipe axial direction. This makes it possible to moderate the gradient of the diameter changing portion 4e with respect to the pipe axis direction. Note that the diameter changing portion 4e is not necessarily limited to a mode in which the tapered portion 12 (outer surface taper portion 12b) overlaps with the pipe axial direction. It may be set only within a range on one side of the portion 12b) in the tube axis direction. Conversely, the range of the diameter changing portion 4e and the range of the outer portion 4b do not overlap in the pipe axial direction, and the range of the diameter changing portion 4e in the pipe axial direction is the tapered portion 12 (outer surface tapered portion 12b). ) may be set only within the range in the tube axial direction.

The outer member 5 includes a base portion 5a in contact with the outer surface 2c of the liner projection portion 2b, and a flange portion 22 rising outward (radially outward) from the base portion 5a. The flange portion 22 of the outer member 5 functions as a second flange portion (hereinafter referred to as the second flange portion 22) of the tightening means 20. As shown in FIG. The inner surface 5d of the outer member 5 is a tapered surface oriented parallel to the outer surface 4c of the inner portion 4a.

The tightening means 20 includes a first flange portion 21 provided on the connection jig 4 and rising outward (radially outward) from the outer portion 4b, a second flange portion 22 provided on the outer member 5, and a first flange portion. 21 and the second flange portion 22 and a nut 24 screwed onto the bolt 23 . By tightening the nut 24 on the bolt 23, the first flange portion 21 and the second flange portion 22 are pulled together in the pipe axial direction. As a result, the liner protruding portion 2b is sandwiched between the outer tapered portion 12b of the inner portion 4a and the inner tapered portion 12a of the outer member 5 in the thickness direction, thereby fixing the mutual members in a liquid-tight and air-tight manner. be able to. At this time, since the outer surface 3c of the guide member 3 is a cylindrical surface, the outer surface 3c of the guide member 3 and the inner surface 5d of the outer member 5 are in sliding contact with each other to guide the movement of the outer member 5 in the direction of the tube axis. . As shown in FIG. 2, a plurality of sets of bolts 23 and nuts 24 are provided along the circumferential direction around the pipe axis in equally divided directions. Although eight sets of bolts 23 and nuts 24 are used in the embodiment, this number can be increased or decreased according to specifications.

Further, since the annular seal member 11 is provided between the outer surface 4c of the inner portion 4a and the inner surface 2d of the liner projection portion 2b, the liquid tightness and airtightness thereof are further enhanced. In this embodiment, an annular O-ring (seal ring) is adopted as the seal member 11 . It is desirable that the seal member 11 be provided in the middle of the tapered portion 12 . It should be noted that the workability of attaching the outer member 5 is good if the outer member 5 is fitted before the liner tube 2 is expanded. In addition, the outer member 5 is not limited to an integral annular member as in the embodiment, but a form in which an annular portion is formed by connecting a plurality of arcuate members in the circumferential direction. By adopting a half-split structure in which two circular arc-shaped members are connected to each other to form an annular ring, it is possible to easily install the liner tube 2 even after the liner tube 2 is expanded, thereby improving workability.

The connecting jig 4 and the tubular body P are connected by connecting means 30 . The connection means 30 includes a third flange portion 31 provided at the pipe end portion p1 of the pipe body P and rising outward (radially outward), and a fourth flange portion provided on a pressing member 32 which is a separate member from the pipe body P. 32 b , bolts 33 passing through the third flange portion 31 and the fourth flange portion 32 b , and nuts 34 screwed onto the bolts 33 . By tightening the nut 34 on the bolt 33, the third flange portion 31 and the fourth flange portion 32b are pulled together in the pipe axial direction. Further, the projecting end 32a located near the inner diameter of the pressing member 32 pushes the rubber ring 35 into the socket of the tubular body P. As shown in FIG. Thereby, the cylindrical portion 4f of the connection jig 4 and the pipe end portion p1 of the pipe body P are fixed in a liquid-tight and air-tight manner.

Another embodiment is shown in FIG. In this embodiment, the diameter changing portion 4e of the connection jig 4 is provided only on the outer portion 4b. In the above-described embodiment, the diameter changing portion 4e of the connection jig 4 is arranged across the inner portion 4a and the outer portion 4b. It is also possible to adopt such a mode. Since other basic configurations are the same as those of the above-described embodiment, description thereof is omitted.

In each of the above embodiments, the tapered portion 12 is provided on both the outer surface 4c of the inner portion 4a and the inner surface 5d of the outer member 5. Only one of them may be used. For example, only the tapered portion 12b on the outer surface of the inner portion 4a may serve as the tapered portion 12, or only the tapered portion 12a on the inner surface of the outer member 5 may serve as the tapered portion 12.

In each of the above-described embodiments, the diameter changing portion 4e is configured to expand in one direction in the pipe axial direction, that is, as it moves away from the end of the existing pipe 1. It is also possible to adopt a configuration in which the diameter is reduced in one direction in the axial direction. At this time, the tapered portion 12 may include both the tapered portion 12 (outer surface taper portion 12b) of the outer surface 4c of the inner portion 4a and the tapered portion 12 (inner surface taper portion 12a) of the inner surface 5d of the outer member 5. , may be provided.

1 Existing pipe 2 Liner pipe 2a Coating portion 2b Liner protrusions 2c, 3c, 4c Outer surfaces 2d, 3d, 4d, 5d Inner surface 3 Guide member (guide ring)
4 Connection jig 4a Inner portion 4b Outer portion 5 Outer member 5a Base portion 10 Pipe joint structure 11 Seal member 12 Tapered portion 12a Internal tapered portion 12b External tapered portion 20 Fastening means 21 First flange portion 22 Second flange portion 23 Bolt 24 nut 30 connection means P tubular body

Claims (5)

an existing pipe (1);
A liner pipe (2) continuously comprising a covering portion (2a) covering the inner surface of the existing pipe (1) and a liner projecting portion (2b) projecting from one axial end of the existing pipe (1) )When,
a guide member (3) arranged outside the liner protrusion (2b);
a connecting jig (4) comprising an inner portion (4a) that enters inside the liner projecting portion (2b) and an outer portion (4b) that projects from the inner portion (4a) in one direction in the pipe axial direction;
an outer member (5) having a base (5a) in contact with the outer surface (2c) of the liner protrusion (2b);
a tapered portion (12) provided on at least one of the outer surface (4c) of the inner portion (4a) and the inner surface (5d) of the outer member (5) and increasing in diameter in the tube axial direction;
Tightening means for fixing the connection jig (4), the liner protrusion (2b) and the outer member (5) by drawing the connection jig (4) and the outer member (5) in the direction of the pipe axis. (20) and
A pipe joint structure comprising: The connecting jig (4) has a diameter changing portion (4e) between the inner portion (4a) and the outer portion (4b), and the diameter changing portion (4e) extends in one direction in the tube axial direction. 2. The pipe joint structure according to claim 1, wherein the diameter is expanded by The pipe joint structure according to claim 1 or 2, further comprising an annular seal member (11) between the outer surface (4c) of the inner portion (4a) and the inner surface (2d) of the liner protrusion (2b). The guide member (3) is composed of an annular member whose outer surface (3c) is a cylindrical surface. 4. The pipe according to any one of claims 1 to 3, wherein the movement of the outer member (5) in the direction of the pipe axis is guided by sliding contact with the inner surface (5d) of the outer member (5). joint structure. The tightening means (20) includes a first flange portion (21) provided on the connecting jig (4) and rising outward from the outer portion (4b), and the base portion provided on the outer member (5). A second flange portion (22) rising outward from (5a), a bolt (23) passing through the first flange portion (21) and the second flange portion (22), and a nut screwed into the bolt (23) The pipe joint structure according to any one of claims 1 to 4, comprising (24).

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