JP2020020369A - Heat retention cover for pipeline - Google Patents

Abstract

To improve attachability of a heat retention pipeline.SOLUTION: A heat retention cover 10 for a pipeline according to the disclosure covers a connection portion between inner pipes 71 each protruding in a pipe length direction at a terminal part of a heat retention pipeline 70 formed by forming a heat retention layer 73 between the inner pipe 71 and an outer pipe 72. The heat retention cover 10 has: a heat retention case 11 which is formed by a heat insulation material and houses the connection portion between the inner pipes 71; and an outer cover 30 which is formed into a cylindrical shape enclosing the heat retention case 11 from the outer side and is fitted in the outer pipe 71 at both end parts. Bellows parts 37 are formed in at least both end parts of the outer cover 30.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a heat insulating cover for a pipe for covering a connecting portion between heat insulating pipes each having a heat insulating layer formed between an inner pipe and an outer pipe.

  The pipe insulation cover of Patent Literature 1 has a heat insulation case that covers a connection portion of inner pipes protruding in a pipe length direction at an end portion of the heat insulation pipe from the outside, and a straight cylindrical shape that covers the whole of the heat insulation case from the outside. And an outer cover in which the outer pipe of the heat retaining pipe is fitted.

JP 2011-75081 A (paragraphs [0024] to [0029], FIGS. 6 and 7)

  In the heat retaining pipe, the center axes of the inner pipe and the outer pipe may be shifted. In such a case, in the heat insulating case for piping of Patent Document 1, the center axis of the heat insulating case covered by the outer cover coincides with the center axis of the inner pipe, and thus it becomes difficult to fit the outer cover to the outer pipe. For this reason, it has been desired to improve the mountability to the heat retaining pipe.

  The invention according to claim 1 made in order to solve the above-mentioned problem is a method of connecting a connecting portion between the inner pipes that protrudes in the pipe length direction at the end of a heat retaining pipe in which a heat insulating layer is formed between an inner pipe and an outer pipe. A heat insulating cover for piping, which is formed of a heat insulating material and is formed of a heat insulating material, and a heat insulating case that accommodates a connection portion between the inner tubes, and a tubular shape surrounding the heat insulating case from the outside, and both ends of the heat insulating case are formed in the outer tube. An outer cover to be fitted, and a bellows portion formed at least at both ends of the outer cover.

  The invention according to claim 2 is characterized in that the heat retaining case has a sleeve portion into which the inner tubes are inserted inside, and a bulging portion bulging radially outward from the sleeve portion. The heat insulating cover for piping according to claim 1, wherein a positioning protrusion for receiving the bulging portion is provided in a concave portion formed in a portion bulging outward and facing inward.

  The invention according to claim 3 is characterized in that the inner pipe is made of resin, and a connection portion between the inner pipes is provided with an electro-fusion joint for fusing the inner pipes by energization. The joint has a tubular body into which the two inner tubes connected to each other are inserted inside, and a pair of electrode portions protruding outward from one location in a circumferential direction of the tubular body, The piping heat retaining cover according to claim 2, wherein a sleeve portion accommodates the cylindrical body, and the bulging portion accommodates the pair of electrode portions.

  The invention according to claim 4 is the piping according to any one of claims 1 to 3, wherein the heat retaining case is formed with a step portion that reduces both ends in the pipe length direction in a stepped manner. Heat insulation cover.

  According to a fifth aspect of the present invention, the heat retaining case is divided into two halves in a cross-section passing through a center line of the inner tube, and an engagement protrusion and an engagement recess are provided on a coupling surface of the halves. The engagement concave portion is formed with the engagement protrusion of the half body before rotation when the half body is rotated by 180 degrees about the center line in the pipe length direction on the coupling surface. The pipe heat insulating cover according to claim 1, wherein the pipe heat insulating cover is arranged to be engaged with the pipe.

  According to the first aspect of the present invention, since the bellows portions are formed at both ends of the outer cover that are fitted to the outer tube, even if the center axes of the inner tube and the outer tube are misaligned, the center of the inner tube may be displaced. The shaft deviation can be absorbed by the bellows. This makes it easier to fit the outer cover to the outer pipe, and improves the attachment to the heat retaining pipe.

  According to the second aspect of the present invention, since the positioning projection of the outer cover receives the bulging portion of the heat retaining case, the outer cover can be positioned on the heat retaining case.

  In addition, an electric fusion joint for fusing the inner tubes to each other by energization is provided at a connection portion between the inner tubes, and the electric fusion joint is a cylindrical body through which the two inner tubes connected to each other are inserted. And a pair of electrode portions protruding outward from one location in the circumferential direction of the cylindrical body. In addition, if a configuration for accommodating a pair of electrode portions (the invention of claim 3), a portion for accommodating the electrode portion of the electrofusion joint in the heat retaining case can be used for positioning with the outer cover.

  According to the fourth aspect of the invention, since both ends in the tube length direction of the heat retaining case are reduced in a stepped shape, even if the bellows portion of the outer cover is inclined with respect to the tube length direction, interference between the bellows portion and the heat retaining case is possible. Is suppressed.

  According to the fifth aspect of the present invention, since the two halves can have the same structure, the types of components of the heat retaining case can be reduced.

Side sectional view of a heat insulation pipe to which a heat insulation cover for piping according to an embodiment of the present disclosure is attached. Perspective view of insulation pipe and electric fusion joint Partially broken perspective view of a heat insulating cover for piping. Perspective view of thermal insulation case (A) AA sectional view, (B) BB sectional view of a heat insulation case Perspective view of two halves Perspective view of outer cover (A) Side sectional view before engagement of locking projection and locking hole, (B) side sectional view after engagement (A) A cross-sectional view of the heat-retaining pipe in which the center axes of the inner pipe and the outer pipe coincide, and (B) a cross-sectional view of the heat-retaining pipe in which the center axes of the inner pipe and the outer pipe are shifted. (A) A sectional side view showing a fitted state of the outer cover and the outer pipe when the central axes of the inner pipe and the outer pipe are coincident, and (B) when the central axes of the inner pipe and the outer pipe are shifted. Side sectional view showing the fitted state of the outer cover and the outer tube

  As shown in FIG. 1, the heat insulating cover 10 for a pipe of the present embodiment (hereinafter, simply referred to as the heat insulating cover 10) covers a connection portion between the two heat insulating pipes 70. The heat retaining pipe 70 has a three-layer structure having a heat insulating layer 73 between an inner pipe 71 and an outer pipe 72. The inner tube 71 and the outer tube 72 are made of, for example, polyethylene resin. The heat insulating layer 73 is made of, for example, polyurethane foam or the like.

  At the connection between the two heat retaining pipes 70, inner pipes 71 projecting in the pipe length direction at the end portions of the respective heat retaining pipes 70 are joined via an electric fusion joint 80. As shown in FIG. 2, the electrofusion joint 80 includes a cylindrical body 81 into which two inner tubes 71 connected to each other are inserted, and a pair of electrode portions 82 projecting outward from the cylindrical body 81. 82. When the coil-shaped heating wire embedded in the cylindrical body 81 is energized through the pair of electrodes 82, the two inner tubes 71 inserted inside the cylindrical body 81 are melted. Be worn. Note that the pair of electrode portions 82, 82 are arranged at the same circumferential position in the circumferential direction of the cylindrical body 81, and are arranged side by side in the axial direction of the cylindrical body 81. In addition, each of both ends of the cylindrical body 81 is provided with a protruding portion 83 that protrudes outward.

  As shown in FIG. 3, the heat insulating cover 10 includes a heat insulating case 11 made of a heat insulating material, and an outer cover 30 surrounding the heat insulating case 11 from outside. The heat insulating material forming the heat retaining case 11 is, for example, a rigid polyurethane foam.

  As shown in FIG. 4, the heat retaining case 11 has a structure in which a part of a cylindrical body is bulged outward, and includes a sleeve portion 12 and a bulge portion 15 protruding outward from the sleeve portion 12. . The bulging portion 15 is disposed at one position in the circumferential direction of the sleeve portion 12 and is formed in a linear shape extending along the axial direction of the sleeve portion 12.

  At both ends of the sleeve portion 12, there are provided step portions 12 </ b> D that reduce the diameter of the end portion of the sleeve portion 12 in a stepped manner. The sleeve portion 12 has a structure in which a large-diameter portion 14 is sandwiched between two small-diameter portions 13. The bulging portion 15 protrudes from the entire large diameter portion 14.

  The space inside the heat retaining case 11 is formed by a joint accommodating portion 16 for accommodating the electric fusion joint 80 and a fitting hole 19 that fits into the two inner tubes 71 connected by the electric fusion joint 80. Become. The joint accommodating portion 16 includes a body accommodating portion 17 accommodating the cylindrical body 81 of the electrofusion joint 80 and an electrode accommodating portion 18 accommodating the pair of electrode portions 82, 82.

  As shown in FIGS. 5A and 5B, the body housing portion 17 is formed in the large diameter portion 14 of the sleeve portion 12 and has a cylindrical shape coaxial with the sleeve portion 12. The electrode housing portion 18 extends radially outward from one location in the circumferential direction of the body housing portion 17 (see FIG. 5B). The electrode accommodating portion 18 is arranged at the same circumferential position as the bulging portion 15 in the circumferential direction of the sleeve portion 12, and is formed across both the sleeve portion 12 (specifically, the large diameter portion 14) and the bulging portion 15. ing. The body accommodating portion 17 is provided with a concave portion 17A for receiving the protruding portion 83.

  The fitting holes 19 extend from both ends in the central axis direction of the sleeve portion 12 along the central axis of the sleeve portion 12. The fitting hole 19 is arranged coaxially with the sleeve 12, similarly to the body housing 17.

  As shown in FIG. 6, the heat retaining case 11 is formed by connecting two half bodies 21. The half body 21 has a semi-cylindrical shape, and two end faces in the circumferential direction form a coupling surface 21M. Further, at one end in the circumferential direction of the half body 21, a projecting portion 25 projecting outward in the radial direction is provided. The overhang portion 25 forms a part of the bulge portion 15 of the heat retaining case 11 (see FIG. 5B). Specifically, the half body 21 is provided with a stepped portion 21 </ b> D that reduces the diameter of the axially distal end in a stepped manner. The half body 21 has a structure in which a large-diameter half-cylindrical portion 24 is sandwiched between two small-diameter half-cylindrical portions 23. The overhang portion 25 projects from the entire large-diameter semi-cylindrical portion 24.

  The round groove portion formed inside the half body 21 includes a large-diameter groove 26 that forms the joint housing 16 of the heat retaining case 11 and a small-diameter groove 29 that forms the fitting hole 19. The large-diameter groove 26 includes a main groove 27 forming the body housing portion 17 and a sub-groove 28 forming the electrode housing portion 18.

  An engagement protrusion 21T and an engagement recess 21A are formed on the coupling surface 21M of the half body 21. The engagement projection 21T and the engagement recess 21A are arranged symmetrically with respect to a center line L1 that bisects the coupling surface 21M in the center axis direction of the half body 21. Therefore, when the half body 21 is rotated by 180 degrees around the center line L1, the engagement projection 21T of the half body 21 after rotation is engaged with the engagement recess 21A of the half body 21 before rotation, The engagement concave portion 21A of the half body after rotation engages with the engagement projection 21T of the half body 21 before rotation. In the present embodiment, since the two half bodies 21 can have the same structure, the types of components of the heat retaining case 11 can be reduced.

  As shown in FIG. 7, the outer cover 30 includes a cylindrical portion 31 and a positioning protrusion 35 protruding outward from the cylindrical portion 31. The cylindrical portion 31 is formed by rolling the resin sheet 30S shown in FIG. Specifically, locking protrusions 32 and locking holes 33 are formed at both ends in the rounding direction of the resin sheet 30S. Then, as shown in FIG. 8B, the outer cover 30 is formed by inserting the locking projection 32 into the locking hole 33 and holding the resin sheet 30S in a tubular shape.

  As shown in FIG. 7, the locking projection 32 includes first locking projections 32 </ b> A arranged at both ends of the cylindrical portion 31 and an axial direction of the cylindrical portion 31 at an intermediate portion of the cylindrical portion 31. And a second locking projection 32 </ b> B extending therefrom. Further, the locking hole 33 is disposed at both ends of the cylindrical portion 31 and is provided at a middle portion of the cylindrical portion 31 with a first locking hole (not shown) through which the first locking protrusion 32A is inserted. And a second locking hole (not shown) through which the second locking projection 32B is inserted.

  As shown in FIGS. 1 and 3, the positioning protrusion 35 is formed by swelling a part of the resin sheet 30 </ b> S radially outward of the cylindrical portion 31. A recess 36 is formed in a portion of the positioning protrusion 35 facing the inside of the cylindrical portion 31.

  Bellows portions 37 are formed at both ends of the outer cover 30. The bellows portion 37 is formed by repeating the mountain fold and the valley fold of the resin sheet 30S constituting the outer cover 30 in the axial direction of the outer cover 30. More specifically, the bellows portion 37 is disposed closer to the distal end of the outer cover 30 than the positioning protrusion 35, and is disposed at a predetermined interval from the distal end of the outer cover 30. The portion of the outer cover 30 that is disposed on the distal side from the bellows portion 37 is a straight cylindrical fitting cylindrical portion 38.

  As shown in FIG. 1, the heat retaining cover 10 of the present embodiment covers the connection part of the two heat retaining pipes 71 together with the electric fusion joint 80. Specifically, the heat retaining case 11 is attached to the electric fusion joint 80 from the outside, and the electric fusion joint 80 is accommodated in the joint accommodating portion 16 of the heat retaining case 11. The inner tube 71 is housed. When attaching the heat retaining case 11 to the electric fusion joint 80, the electric fusion joint 80 is inserted into a round groove portion inside one of the two half bodies 21 constituting the heat retaining case 11. In the received state, the electro-fused joint 80 is received in the round groove portion inside the other half body 21 to join the two half bodies 21 together.

  As shown in FIGS. 1 and 3, the outer cover 30 is attached to the heat retaining case 11 so as to surround the heat retaining case 11 from outside. At this time, the bulging portion 15 of the heat retaining case 11 is received in the concave portion 36 formed inside the positioning protrusion 35 of the outer cover 30. Thus, the outer cover 30 is positioned with respect to the heat retaining case 11 in both the circumferential direction and the axial direction.

  With the outer cover 30 attached to the heat retaining case 11, the bellows portion 37 of the outer cover 30 is disposed closer to the distal end of the sleeve portion 12 than the large diameter portion 14 in the center axis direction of the sleeve portion 12. In the present embodiment, the bellows portion 37 is disposed so as to surround the small diameter portion 13 of the sleeve portion 12 in the heat retaining case 11 from the outside, and the edge of the bellows portion 37 facing the center of the outer cover 30 in the axial direction is a sleeve portion. It is arranged outside the twelve steps 12D.

  As shown in FIG. 1, both ends of the outer cover 30 (specifically, the fitting cylinder 38) are fitted to the outer pipe 72 and bonded to the outer pipe 72. When a gap is formed between the heat insulating layer 73 of the heat insulating pipe 70 and the heat insulating case 11, a heat insulating tape (not shown) is wound around the inner pipe 71 exposed in the gap.

  Here, the heat retaining pipe 70 is designed so that the central axes of the inner pipe 71 and the outer pipe 72 coincide with each other (see FIG. 9A), but when the central axes of the inner pipe 71 and the outer pipe 72 are shifted. (See FIG. 9B). In such a case, the central axis of the heat retaining case 11 (specifically, the central axis of the sleeve portion 12) covered by the outer cover 30 substantially coincides with the central axis of the inner pipe 71, so that the outer cover 30 is attached to the outer pipe 72. A problem that the fitting cannot be performed may occur. However, in the heat retaining cover 10 of the present embodiment, the deviation of the central axes of the inner pipe 71 and the outer pipe 72 can be absorbed by the bellows 37 formed at both ends of the outer cover 30.

  That is, as shown in FIG. 10B, the center axis of the portion of the outer cover 30 wrapped around the heat retaining case 11 coincides with the center axis of the inner tube 71, while the fitting cylinder of the outer cover 30 is fitted. The central axis of the portion 38 is allowed to deviate from the central axis of the inner tube 71 due to the bending of the bellows portion 37. Thus, the center axis of the fitting tube 38 can be made to coincide with the center axis of the outer tube 72, and the fitting tube 38 can be fitted to the outer tube 72.

  In addition, since the step portion 12D is formed in the sleeve portion 12, the bellows portion 37 has a gap between the bellows portion 37 and the sleeve portion 12 (small diameter portion 13) disposed inside. This suppresses interference with the sleeve portion 12 when the bellows portion 37 bends.

  As another means for fitting the outer cover 30 to the outer tube 72 when the center axes of the inner tube 71 and the outer tube 72 are misaligned, at least both ends of the outer cover 30 may be constituted by heat-shrinkable tubes. Conceivable. Specifically, the outer diameter of the heat-shrinkable tube is made larger than the outer diameter of the outer tube 72, and the heat-shrinkable tube is heated with the outer tube 72 inserted through the heat-shrinkable tube. Thereby, even if the center axes of the inner pipe 71 and the outer pipe 72 are misaligned, both ends of the outer cover 30 can be fitted to the outer pipe 72.

[Other embodiments]
(1) The positioning protrusion 35 may be present at a plurality of locations in the circumferential direction of the outer cover 30 or at a plurality of locations in the axial direction. As an example of the latter, the positioning projection 35 may be configured by a projection.

  (2) The sleeve portion 12 of the heat retaining case 11 may be formed in a straight cylindrical shape, and may not include the step portion 12D. Even with such a configuration, interference between the bellows portion 37 and the sleeve portion 12 can be avoided by lengthening the bellows portion 37 in the axial direction of the outer cover 30. In the above embodiment, the provision of the step portion 12D in the sleeve portion 12 makes it possible to shorten the bellows portion 37, and the outer cover 30 is made compact.

  (3) The configuration may be such that the heat retaining case 11 does not include the bulging portion 15 and the outer cover 30 does not include the positioning protrusion 35. In this case, the outer cover 30 may not be provided with the locking projection 32 and the locking hole 33, and the outer cover 30 may not be opened or closed.

  (4) The bellows 37 may be formed at least at both ends of the outer cover 30, and may be formed, for example, over the entire outer cover 30 in the axial direction.

  (5) In the above embodiment, the two inner tubes 71 are connected to each other by the electric fusion joint 80. However, for example, when a flange is formed at the end of the inner tube 71, the two inner tubes 71 are connected by the flange. May be done. In this case, the inner tube 71 is not limited to the resin and may be, for example, a metal.

  (6) In the above embodiment, the heat retaining pipe 70 is connected by a socket, but may be an elbow connection or a cheese connection.

DESCRIPTION OF SYMBOLS 10 Heat insulation cover for piping 11 Heat insulation case 12 Sleeve part 12D Step part 15 Swelling part 21 Half body 30 Outer cover 33 Positioning protrusion 35 Bellows part 70 Heat insulation pipe 71 Inner pipe 72 Outer pipe 73 Heat insulation layer 80 Electric fusion joint

Claims (5)

A heat insulating cover for a pipe that covers a connection portion between the inner pipes that protrudes in a pipe length direction at an end of the heat insulating pipe in which a heat insulating layer is formed between an inner pipe and an outer pipe,
A heat insulation case configured of a heat insulating material and housing a connection portion between the inner tubes,
An outer cover formed in a tubular shape surrounding the heat retaining case from the outside, and both ends fitted to the outer tube,
A thermal insulation cover for piping, wherein bellows portions are formed at least at both ends of the outer cover. The heat retaining case has a sleeve portion through which the inner tubes are inserted, and a bulging portion bulging radially outward from the sleeve portion.
The heat insulating cover for piping according to claim 1, wherein the outer cover is provided with a positioning projection that receives the bulging portion by a concave portion formed in a portion bulging outward and facing inward. The inner tube is made of resin,
An electrical fusion joint that fuses the inner tubes by energization is provided at a connection portion between the inner tubes,
The electrofusion joint includes: a tubular body into which the two inner tubes connected to each other are inserted inside; and a pair of electrode portions protruding outward from one location in a circumferential direction of the tubular body. Have
The heat insulating cover for piping according to claim 2, wherein the sleeve portion accommodates the cylindrical body, and the bulging portion accommodates the pair of electrode portions.   4. The thermal insulation cover for a pipe according to claim 1, wherein the thermal insulation case is formed with a stepped portion that reduces both ends in the pipe length direction in a stepped manner. 5. The heat retaining case is divided into two halves at a cross section passing through a center line of the inner tube,
An engagement projection and an engagement recess are formed on the coupling surface of the half body,
The engagement recess engages with the engagement protrusion of the half body before rotation when the half body is rotated 180 degrees about the center line in the pipe length direction on the coupling surface. The piping heat insulating cover according to any one of claims 1 to 4, which is arranged as follows.