JP4903497B2 - Telescopic tube device - Google Patents

Description

  The present invention relates to an expansion and contraction pipe device used for the purpose of absorbing displacement due to temperature change of a pipe such as a water pipe, ground subsidence, earthquake, and the like in an exposed part and a buried part of a water pipe bridge.

  In a conduit of a conduit for flowing a fluid such as a water pipe, an expansion / contraction pipe device is used as a pipe joint for absorbing expansion / contraction due to temperature change. In general, the expansion / contraction tube device has a stretchable bellows tube as a main component, and the expansion / contraction of the bellows tube absorbs the expansion / contraction associated with the temperature change of the pipeline.

  This bellows tube has a characteristic that when the compressive force in the axial direction is excessively applied, the bellows buckles in a direction perpendicular to the axial line. Therefore, the present applicant has proposed a telescopic tube device as shown in FIG. The telescopic tube device 100 includes a bellows tube 101, end tubes 102 and 103 attached to each end of the bellows tube 101, a first cover 106 and a second cover disposed outside the bellows tube 101. 107.

  The first and second covers 106 and 107 are straight pipes that are thicker than the bellows pipe 101 having a length about half that of the bellows pipe 101, and one end portion of the collars 104 and 105 fixed to the end pipes 102 and 103. The tip end portions overlap each other in a movable state in the central portion of the bellows tube 101. In addition to protecting the bellows tube 101 from external impacts and the like, the first and second covers 106 and 107 have the bellows against the axis when a compressive force in the axial direction of the bellows tube 101 is applied. In other words, it functions to suppress buckling in a right angle direction and to ensure the straightness of expansion and contraction of the bellows tube 101 at the overlapping tip portion.

  On the other hand, in the telescopic tube device 100, the straight tube-shaped first and second covers 106 and 107 are provided in order to ensure that the bellows buckles and the bellows tube 101 expands and contracts, so that the axial direction However, it is configured such that it cannot be bent in a direction perpendicular to the axial direction.

  By the way, there is a demand for an expansion and contraction tube device using a bellows tube that can also be used to absorb displacement during an earthquake or the like. In order to realize an expansion / contraction tube device using a bellows tube that also supports displacement absorption, the expansion / contraction in the axial direction of the bellows tube 101 is not sufficient as in the expansion / contraction tube device 100 shown in FIG. Need to absorb. Furthermore, in order to realize a telescopic tube device using a bellows tube corresponding to high-level earthquake motion with a low probability of occurrence, it is necessary to bend in a direction perpendicular to the axial direction of the bellows tube 101. However, as described above, in the telescopic tube device 100 as shown in FIG. 4, the straight tubular first and second covers 106 and 107 are disposed so that the tip ends overlap with the outside of the bellows tube 101. Therefore, it cannot be bent so as to absorb the angular displacement, and it cannot be bent in a direction perpendicular to the axial direction of the bellows tube 101.

  In this regard, Patent Document 1 describes an expansion and contraction tube device using a bellows tube that can handle earthquake motion. In the telescopic tube device of Patent Document 1, the bellows tube is exposed and used so as not to impair the expansion and bending characteristics of the bellows tube. However, the bellows pipe of Patent Document 1 cannot be sufficiently protected against an external impact or the like because the bellows pipe is exposed. Further, as described above, when the compressive force in the axial direction is excessively applied, the bellows buckles in the direction perpendicular to the axial line in the telescopic tube device of Patent Document 1. Further, in Patent Document 1, since the sleeve tube serving as the end tube enters the bellows from both sides, when the amount of the sleeve tube entering the bellows increases, the bellows in the direction perpendicular to the axis is increased. Bending characteristics will be greatly limited.

Japanese Patent Laid-Open No. 2005-273772

  The present invention has been made in view of the above-described problems, and its purpose is not only linear displacement in the axial direction, but also angular displacement, and a direction perpendicular to the axial direction associated with earthquake motion. An object of the present invention is to provide a telescopic tube device that can also absorb the displacement of.

  The telescopic tube device according to the present invention includes a bellows tube through which a fluid flows, an end tube attached to each end of the bellows tube, and a bellows formed outside the bellows tube. A first cover extending in the direction of the central portion of the axis of the bellows pipe with the one end side of the pipe as a fixed end, a bellows is formed, and the bellows pipe is formed outside the bellows pipe. And a second cover extending in the direction of the central portion of the axis of the bellows tube.

The first cover has a first straight pipe portion formed at a tip portion on the center portion side of the axis of the bellows tube, and the second cover has a tip on the center portion side of the axis of the bellows tube. A second straight pipe part is formed in the part. The first straight pipe portion and the second straight pipe portion are overlapped so as to be movable at a substantially central portion of the bellows pipe. The length at which the first straight pipe portion and the second straight pipe portion overlap is longer than half of the expansion / contraction amount of the bellows pipe guaranteed by normal use.

  The telescopic tube device as described above is guided by the overlapping portion of the straight tube portion of the first cover and the straight tube portion of the second cover, and the bellows tube expands and contracts in the axial direction. In addition, when the telescopic tube device is displaced in an angular displacement or a direction perpendicular to the axial direction of the bellows tube, the first cover and / or the second cover is displaced following the displacement of the bellows tube, One side of the cover will bend.

According to the present invention, the expansion and contraction of the pipe line accompanying a temperature change or the like can be absorbed by linearly displacing in the axial direction of the bellows pipe. In addition, angular displacement and displacement in a direction perpendicular to the axial direction due to seismic motion or the like can be absorbed by displacement of the first cover and / or the second cover following the displacement of the bellows tube. . In the present invention, since the first and second covers are provided outside the bellows tube, it is possible to prevent the bellows tube from buckling in the direction perpendicular to the axis as in the prior art. .
Further, when a high level earthquake occurs and the pipe is greatly displaced, the bellows pipe extends while being displaced in a direction perpendicular to the axis, and accordingly, the first and second covers are overlapped with the straight pipe. The part will come off. Therefore, it is possible to prevent water leakage.

  Hereinafter, an expandable tube device 10 to which the present invention is applied will be described with reference to the drawings.

  As shown in FIG. 1, the telescopic pipe device 10 to which the present invention is applied includes an aqueduct, a bridge, and an elevated water tank for the purpose of absorbing expansion / contraction due to temperature change of a pipe line, displacement due to ground subsidence, and displacement accompanying earthquake motion. It is used as a joint of the exposed water pipe 2 attached to the structure 1 such as the above. The pipe of the water pipe 2 including the expansion / contraction tube device 10 is supported substantially linearly on the structure 1 by the support member 3 on both sides of the expansion / contraction tube device 10. Is supported by the support member 3 in a state in which expansion and contraction in the axial direction is allowed.

  In addition, although the steel pipe, the cast iron pipe, the synthetic resin pipe made from vinyl chloride, etc. are used as the water pipe 2, the telescopic pipe device 10 to which the present invention is applied can be connected to any kind of water pipe. It is.

  As shown in FIGS. 2 and 3, the telescopic tube device 10 to which the present invention is used as described above includes a bellows tube 11 having flexibility, stretchability, and further sealing, and both ends of the bellows tube 11. And a pair of end tubes 12 and 13 that are integrally joined to the respective portions.

  The bellows tube 11 is made of a stainless material having excellent mechanical characteristics and rust prevention, and connecting portions 11b and 11b for connecting to the end tubes 12 and 13 are integrally formed at both ends of the bellows body 11a having a substantially corrugated cross section. It is provided. The bellows tube 11 is formed so as to have a predetermined flexibility and stretchability by determining the plate thickness, the number of bellows, the height, and the like in consideration of the thickness, application, and the like of the tube. Moreover, the bellows main body 11a has sufficient strength to withstand the force caused by the internal pressure of tap water flowing inside. Each convex part 11c which comprises the bellows of the bellows main body 11a is formed in the cross-sectional inverted U shape where the front-end | tip raises substantially circular arc, for example. By forming each convex part 11c into an inverted U-shaped cross section, it is less likely to be crushed than when it is formed into a substantially Ω-shaped cross section, and the strength is increased. In addition, as long as necessary strength is obtained by the plate thickness or the like, each convex portion 11c may have a substantially Ω cross-sectional shape or other shapes.

  Moreover, the bottom part of the ditch | groove formed by each convex part 11c which comprises the bellows of the bellows main body 11a is formed so that it may not become smaller than the internal diameter of the cylindrical connection part 11b. Thereby, the flow path of the bellows pipe 11 does not become narrower than the connection part 11b, and it can prevent that the flow of tap water is prevented by the part of the bellows main body 11a.

  The bellows tube 11 configured as described above forms a bellows by compressing a raw tube formed of a stainless steel plate having a length approximately three times the length in the tube axis direction, and then forming the bellows. In order to prevent stress cracking due to residual stress, a solution heat treatment is performed, and then the surface is subjected to acid cleaning to remove residues after the heat treatment. Since the bellows tube 11 is changed from an elastic body to a plastic body by this heat treatment, a restoring force unlike the elastic body is not generated, and when bent, the bent shape is maintained. In addition, the manufacturing method of the bellows pipe | tube 11 is not limited to the above example, For example, you may abbreviate | omit heat processing and an acid treatment.

  In addition, about the bellows pipe | tube 11, it is not limited to a stainless steel material, For example, you may use what was formed with other appropriate metals, such as copper, titanium, an aluminum alloy, or a synthetic resin. Further, the bellows tube 11 may be configured by conducting a flexible conduit inside to prevent solid matter from staying inside due to the uneven structure of the bellows and causing a clogging phenomenon.

  The end tubes 12 and 13 are connected to the connection portions 11b and 11b at both ends of the bellows tube 11 formed of stainless steel, and have an inner diameter substantially equal to the outer diameter of the connection portions 11b and 11b. Have. The end tubes 12 and 13 have one end portions 12a and 13a fitted to the outer peripheral portions of the connection portions 11b and 11b of the bellows tube 11, and the tip portions of the connection portions 11b and 11b and the inner peripheral surfaces of the end tubes 12 and 13 are connected. By being welded, it is integrated with the bellows tube 11 (the weld location is indicated by 20a in FIG. 2). The other end portions 12 b and 13 b of the end tubes 12 and 13 are joined to the end portions of the water pipes 2 and 2. The connection between the bellows tube 11 and the end tubes 12 and 13 may be welded to the outermost convex portions 11d and 11d of the bellows.

  The other end portions 12b and 13b of the end pipes 12 and 13 and the end portions of the water pipes 2 and 2 are, for example, flanges provided at the other end portions 12b and 13b of the end pipes 12 and 13 and the end portions of the water pipe 2. Are connected to each other by tightening the abutted flanges with bolts and nuts. Of course, the mechanism for connecting the end pipes 12 and 13 and the water pipes 2 and 2 is not limited to this, and other known mechanisms can also be used.

  Further, ring-shaped flanges 14 and 15 made of a metal material such as stainless steel are fitted to the outer peripheral portions of the end portions 12 a and 13 a of the end tubes 12 and 13. And the one end parts 12a and 13a of the end pipes 12 and 13 are integrated with the inner peripheral part of the collars 14 and 15 by welding (a welding location is shown by 20b in FIG. 2). In addition, you may weld with the outermost convex parts 11d and 11d of the bellows pipe | tube 11 using this welding location 20b. When the connecting portions 11b and 12b are fitted to the end tubes 12 and 13, the flanges 14 and 15 are abutted from the outside to the outermost convex portions 11d and 11d of the bellows main body 11a, so that the end portions of the bellows main body 11a Protect.

  A first cover 16 is attached to the outer periphery of the collar 14, and a second cover 17 is attached to the outer periphery of the collar 15. The first and second covers 16 and 17 are made of a stainless material having excellent mechanical characteristics and rust prevention properties, and are bellows tubes having a substantially corrugated cross section. And the shape of the convex part of a bellows and the number of convex parts of the 1st and 2nd covers 16 and 17 are determined by the performance required (for example, intensity and flexibility). The first and second covers 16 and 17 have a diameter larger than that of the bellows pipe 11 and are sized so that a gap is formed between the first and second covers 16 and 17. The clearance between the bellows tube 11 and the first and second covers 16 and 17 is such that the bellows of the bellows tube 11, that is, the convex portion 11c can be prevented from buckling in a direction perpendicular to the direction perpendicular to the axis. The bellows tube 11 can be slightly bent in the first and second covers 16 and 17. The first and second covers 16 and 17 are formed slightly longer than half the length of the bellows body 11a. The base ends of the first and second covers 16 and 17 are integrated with the outer peripheries of the flanges 14 and 15 by welding (the welding location is indicated by 20c in FIG. 2).

  Unlike the bellows pipe 11, the first and second covers 16 and 17 are not subjected to force or the like due to the internal pressure of tap water, and do not need to ensure watertightness. It is only necessary to be fixed. Therefore, the connection between the bellows tube 11 and the end tubes 12 and 13 is simple and simple. In addition, the fixing method to the bellows pipe | tube 11 of the 1st and 2nd covers 16 and 17 is not limited to the fixing method using the eaves 14 and 15, Various fixing methods can be used.

  Moreover, the front-end | tip part of the 1st and 2nd covers 16 and 17 is not formed with the bellows, but is the straight pipe parts 16a and 17a, and the straight pipe part 16a is the outside and the straight pipe part 17a is the inside. Are overlaid. The portion where the straight pipe portions 16a and 17a overlap ensures straight advanceability when the bellows pipe 11 expands and contracts in the axial direction.

  Here, the overlapping length L of the straight pipe portions 16a, 17a is at least longer than half of the amount of expansion / contraction guaranteed by normal use of the bellows body 11a. This is to prevent the straight pipe portions 16a and 17a from being uncoupled when the bellows main body 11a extends linearly or when the bellows main body 11a is curved and the outer side extends. For example, when using the bellows tube 11 with an expansion / contraction amount of ± 25 mm, the overlapping length L of the straight pipe portions 16a, 17a is longer than 25 mm, for example, 30 mm or 40 mm, and the expansion / contraction amount is ± 50 mm. Is used, the overlapping length L of the straight pipe portions 16a and 17a is longer than 50 mm, for example, 60 mm and 70 mm.

  The first and second covers 16 and 17 as described above are exposed pipes and protect the bellows pipe 11 from external impacts and the like, similarly to the conventional first and second covers 106 and 107. The overlapping straight pipe portions 16a and 17a move to each other and have a function of ensuring straightness when the bellows pipe 11 expands and contracts in the axial direction. The first and second covers 16 and 17 prevent the bellows from buckling in the direction perpendicular to the axis when the compressive force is excessively applied in the axis direction of the bellows tube 11. The first and second covers 16 and 17 are formed of bellows tubes, so that when the inner bellows tube 11 is bent, that is, when it is angularly displaced or displaced in a direction perpendicular to the axis, It will follow and be displaced.

  By the way, since the 1st and 2nd covers 16 and 17 are arrange | positioned outside the bellows pipe | tube 11 through which tap water flows, the force by the internal pressure of the tap water which flows inside like the bellows pipe 11 is added. Not a thing. For this reason, the first and second covers 16 and 17 can be made lower in physical strength than the bellows tube 11. Specifically, the bellows pipe 11 through which tap water flows has a plate thickness of 2.5 mm and 3 mm, whereas the first and second covers 16 and 17 have a plate thickness of about 1.2 mm. It is thinner than the bellows tube 11 and the end tubes 12 and 13. However, when the bellows tube 11 is thin, the first and second covers 16 and 17 may be thicker.

  Although the first and second covers 16 and 17 can be manufactured in the same manner as the bellows tube 11, the quality is not as high as that of the bellows tube 11. The heat treatment and acid treatment for removing residues may be omitted.

  In addition, the first and second covers 16 and 17 may be made of other appropriate metals such as copper, titanium, aluminum alloy, or synthetic resin, like the bellows tube 11.

  As shown in FIG. 1, the telescopic pipe device 10 configured as described above is used as a joint of an exposed water pipe 2 attached to a structure 1 such as a water bridge, a bridge, and an elevated water tank. That is, in the telescopic pipe device 10, the end pipes 12 and 13 are watertightly connected to the end of the water pipe 2 whose vicinity of the connection end is supported by the support member 3 of the structure 1 by a flange joint or the like. Under normal circumstances, for example, the pipe line of the water pipe 2 expands and contracts due to a temperature change. This expansion and contraction is caused by the bellows pipe 11 of the expansion pipe device 10 being the straight pipe portions 16a and 17a of the first and second covers 16 and 17. Is absorbed by expanding and contracting in the axial direction while guiding straightness at the overlapped portion.

  Further, when a land subsidence or a low-grade earthquake occurs, the water pipe 2 may be displaced in a direction perpendicular to the bellows pipe 11 or the bellows pipe 11 in an angular displacement. Also in this case, the telescopic pipe device 10 can absorb the displacement of the water pipe 2 by the displacement of the bellows pipe 11 together with the first cover 16 and / or the second cover 17. In the telescopic tube device 10, both the first cover 16 and the second cover 1 may be displaced, or only one of the first cover 16 and the second cover 17 may be displaced. .

Further, when a high level earthquake occurs and the water pipe 2 is greatly displaced, the bellows pipe 11 is extended while being displaced in a direction perpendicular to the axis, and accordingly, the first and second covers 16 and 17 are expanded. The straight pipe portions 16a and 17a that overlap each other will come off. Therefore, it is possible to prevent water leakage.

  In addition, when an excessive compressive force is applied in the axial direction of the bellows tube 11, the telescopic tube device 10 has the bellows, that is, the convex portion 11c perpendicular to the axis by the first and second covers 16 and 17. It is possible to suppress buckling in the direction.

  As described above, the telescopic pipe device 10 used as a joint of the exposed water pipe 2 has been described as an example, but the present invention may be used as an embedded type.

  The present invention is also applicable to plumbing work for middle water conduits and sewage pipes, and further, a fluid such as a gas such as city gas or cooling gas, or a solid such as a powder, granule or gel is flowing. It can also be applied to pipe construction.

It is a side view which shows the use condition of the expansion-contraction tube apparatus to which this invention is applied. It is sectional drawing of the expansion-contraction tube apparatus to which this invention is applied. (A) is a side view of the telescopic tube device to which the present invention is applied, and (B) is a front view. It is sectional drawing of the conventional expansion-contraction apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Structure, 2 water pipe, 3 support member, 10 expansion-pipe apparatus, 11 bellows pipe, 11a bellows main body, 11b connection part, 11c convex part, 11d outermost convex part, 12, 13 end pipe, 12a, 13a one end part , 12b, 13b The other end, 14, 15 鍔, 16 First cover, 16a Straight pipe part, 17 Second cover, 17b Straight pipe part, 20a-20c

Claims (4)

A bellows tube through which fluid flows,
An end tube attached to each end of the bellows tube;
A first cover that extends in the direction of the central portion of the axis of the bellows pipe, with the bellows pipe formed on the outer side spaced apart from the bellows pipe, with one end of the bellows pipe as a fixed end;
A bellows is formed and a second cover extending outside the bellows pipe and extending in the direction of the central portion of the axis of the bellows pipe with the other end of the bellows pipe as a fixed end. Prepared,
The first cover has a first straight pipe portion formed at a tip portion on the center side of the axis of the bellows pipe,
The second cover has a second straight pipe portion formed at a tip portion on the center side of the axis of the bellows pipe,
The first straight pipe portion and the second straight pipe portion are movably overlapped at a substantially central portion of the bellows pipe,
The length of the overlap between the first straight pipe portion and the second straight pipe portion is longer than half of the expansion / contraction amount of the bellows pipe guaranteed by normal use .   The telescopic tube device according to claim 1, wherein the first and second covers have lower physical strength than the bellows tube. Said first cover, said at least one fixed end of the second cover, according to claim 1 or claim 2 wherein, characterized in that it is fixed to the outer peripheral portion of the flange which is fixed to an end portion of the end tube Telescopic tube device.   The telescopic tube device according to any one of claims 1 to 3, wherein the telescopic tube device is a joint of an exposed water pipe.

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