JP2004144246A - Low-loss head type annular body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-loss head type annular body for reducing a water flow resistance to the utmost. <P>SOLUTION: As the low-loss head type annular body 10, a flowing directional end of an annular body body 11 has a bell-mouth shape 20 having a nearly crescent cross section and having a diameter larger than water-cut projections 16 and 17 to be pushed to a tube-inside wall 23 by a fixed plate 14, to which the annular body body 11 is to be fitted. Haunch parts 21 and 22 for compressing the bell-mouth shape 22 for fixation when the annular body body 11 is pushed to the tube-inside wall 23 by the fixed plate 14 is provided in a corner of a fixed plate fitting recessed part 15. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-loss head-shaped annulus which is attached to a portion of an inner wall of a pipe for the purpose of stopping water and does not cause a substantial reduction in water supply capacity.
[0002]
[Prior art]
The pipes buried in the ground are subject to various external forces due to long-term use, and for example, they tend to leak water at the pipe connection, and in the case of concrete pipes, crack each part. Such a situation can occur. In such a case, conventionally, repairs have been made by performing water leakage prevention work on the place where the problem occurred, and when the construction target is in the pipe, the members used for water leakage prevention remain on the pipe inner wall Therefore, there arises a problem of resistance generated in the water flow.
[0003]
In one example of the water leakage prevention shown in FIG. 5, a method is adopted in which an annular body c is arranged at the pipe connection part and pressed against the inner wall b of the pipe using a metal-plate-shaped fixing plate d. The water flow resistance of the annular body c causes a reduction in the amount of water supply, which causes practical inconvenience. Therefore, a low-loss water head type annular body c is required. For this reason, an attempt was made to reduce the water flow resistance by making the end of the annular body c into a bell mouth shape e. However, in the conventional shape, when the flow velocity becomes high, the tip g of the bell mouth shape e peels due to the resistance due to the water flow. Sometimes the expected results could not be obtained.
[0004]
Further, in the annular body c shown in FIG. 5, the tension resistance of the annular body c is set to be larger than the frictional resistance generated in the water stopping ridge f by the fixing plate d, and the pipe connecting portion expands and contracts or bends. When this is done, sliding occurs between the water stopping ridge f and the inner wall b of the pipe to cope with expansion and contraction and refraction. However, the inner wall b of the pipe has irregularities, and if the water stopping ridge f slides, it may be difficult to secure the water stoppage, and in some cases, the cost of repairing the unevenness of the inner wall b of the pipe increases.
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above points, and an object thereof is to reduce water flow resistance by an annular body as much as possible. Another object of the present invention is to provide appropriate elasticity and flexibility to a pipe connection while suppressing repair costs.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a low-loss water head type annular body, in which the end of the annular body in the flow direction is pressed against the inner wall of the pipe by a fixing plate to which the annular body is attached. It has a large diameter and has a bell mouth shape with a nearly crescent cross section.When the annular body is pressed against the inner wall of the pipe by a fixing plate, a haunch portion for compressing and fixing the bell mouth shape is provided. In this case, means is provided at the corner of the fixing plate mounting recess.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The low-loss head-shaped annular body of the present invention is mounted for the purpose of stopping water over a part of the inner wall of the pipe, and is capable of maintaining a substantial water supply capacity. Here, the pipe itself is made of any material and is not limited to concrete.
[0008]
The annular body has a literally annular shape and is formed to a size that can be pressed against the inner wall of the pipe, and has a length covering a specific portion of the inner wall of the pipe to be repaired, and a pipe connecting portion. It has the required length. At the end in the flow direction of the annular body, a bell mouth shape which is pressed against the inner wall of the pipe by a fixing plate and has a larger diameter than the water stopping ridge and also has a substantially crescent cross section is provided. . In the conventional bell mouth shape, the diameter of the tip portion g is made larger than the tube diameter, so that the bell mouth is pressed against the tube wall when the annular body is mounted. However, since the bell mouth shape e is not directly compressed, the height is high. When the flow velocity is reached, the tip may be separated due to the loss of water flow resistance. To improve this, it is effective to make the diameter larger than the water stopping ridge, and at the same time, it is effective to sufficiently compress the bell mouth shape.
[0009]
From this viewpoint, in the present invention, when the annular body is pressed against the inner wall of the tube by the fixing plate, a haunch portion for compressing and fixing the bell mouth shape is formed on the inner surface of the annular body for attaching the fixing plate. It is provided at the inner corner of the recess. Since the haunch portion is provided so that the pressing force by the fixing plate effectively reaches the end of the annular body having the bell mouth shape, the bell mouth shape of the end of the annular body is reliably secured, The resistance of the water flow can be reduced as expected. The cross-sectional shape of almost crescent shape directs the pressing force in the direction of the inner wall of the pipe by the fixing plate to bell-mouth shape in the same way that applying a force to an arbitrary point in the arch shape causes the arch to bend and stress to concentrate on the tip end. It is effective.
[0010]
Further, when the annular body is disposed at the pipe connecting portion, the inner surface of the annular body that is in contact with the water flow is made a smooth surface in order to make the annular body expandable and contractable by expansion and contraction or refraction of the pipe connecting portion. The annular body has a corrugated cross-sectional shape in which a groove corresponding to the thin groove on the inner surface is formed as a peak and an adjacent portion is formed as a valley. Thereby, it is possible to provide elasticity and flexibility and not to deviate hydraulically from the purpose of a low-loss head. The narrow groove is for facilitating the bending of the annular body, and is closer to a cut-like shape than a groove.
[0011]
【Example】
Hereinafter, the present invention will be described in more detail with reference to the illustrated embodiments. FIG. 1 shows a part of a longitudinal section of a low-loss water-head type annular body 10 of the present invention, and FIG. 2 shows an enlarged view of a main part thereof.
[0012]
In each of the drawings, reference numeral 11 denotes an annular body having a cylindrical shape as a whole, and fixed portions 12 and 13 are provided at both ends in the flow direction. On the inner surface of each of the fixing portions 12 and 13, there is formed a fixing plate mounting recessed portion 15 large enough to receive the fixing plate 14, and on the outer surface of each of the fixing portions 12 and 13, a fixing plate 14 is provided. The water stop ridges 16 and 17 pressed against the pipe inner wall 23 are provided at intervals corresponding to the width of the fixing plate 14. Each ridge 16, 17 has a base 16a, 17a that supports a sharp tip. Reference numeral 18 denotes a support portion, which secures the flatness between the fixed plate 14 and the inner smooth surface 27 together with the base portions 16a and 17a. Reference numeral 19 denotes a stress concentration ridge provided in the fixing plate mounting recess.
[0013]
The bell mouth shape 20 is provided so as to protrude outward in the flow direction of the fixing portions 12 and 13, and has an outwardly curved crescent that has an outer curvature R1 that is greater than or equal to the inner curvature R2. It has a cross-sectional shape of a shape or a substantially rectangular shape. Further, haunch portions 21 and 22 for compressing the bell mouth shape 20 are provided at inner corners of the fixing portion mounting recess 15. The haunch portions 21 and 22 are force points acting at right angles to an arch-shaped fulcrum connecting the distal end portion 20a of the bell mouth shape 20 and the water stopping ridge 16, and press the distal end portion 20a against the inner wall of the pipe to form a bell mouth shape. 20.
[0014]
With the fixing portions 12 and 13, the bell mouth portion 20 and the support portion 18 configured as described above, the pressing force of the fixing plate 14 is more than sufficiently absorbed, and the separation by the water flow which is expected to act on the distal end portion 20 a is performed. The annular body 10 can be attached to the tube inner wall 23 with a force larger than the acting force (see FIG. 3). In FIG. 3, the reinforcing pipe 25 is mounted on the inner surface of the pipe 24. In this case, the reinforcing pipe 25 is mounted inside the support portion 18.
[0015]
Between the fixing portions 12 and 13 at both ends of the annular body 11, there is a structure portion 26 that can expand and contract and bend. For this purpose, the inner surface of the annular body that is in contact with the water flow is a smooth surface 27, and a thin groove 28 is formed therein. A corrugated cross-sectional shape 29 is formed in which a portion corresponding to the thin groove 28 on the outer surface of the annular body main body is a peak, and an adjacent portion is a valley. In the present invention, the narrow groove 28 is a means for making the annular body 11 easily bendable, and it is necessary to make the groove width as narrow as possible so that the hydraulic resistance does not increase hydraulically.
[0016]
As shown in FIG. 4, the annular body 10 according to the present invention is disposed at the pipe connection part 30, one fixed part 12 is provided on one pipe inner wall 23, and the other fixed part 13 is provided on another one pipe inner wall. 23 'are attached using fixing plates 14, respectively. As a result, when the relative movement of the connected tubes 24, 24 'occurs, the annular body 10 of the present invention can expand and contract or bend in accordance with the movement, so that the annular body 10 has the same structure as the conventional annular body. It is not necessary to slide on the pipe, and the work of repairing irregularities so that the inner wall of the pipe is suitable for sliding is not required.
[0017]
【The invention's effect】
Since the present invention is configured and operates as described above, the bell mouth shape can be maintained as designed, and the water flow resistance due to the annular body can be extremely reduced, and the repair cost can be reduced. While appropriate elasticity and flexibility can be imparted to the pipe connection part.
[Brief description of the drawings]
FIG. 1 is a partial longitudinal sectional view showing an embodiment of a low-loss water-head type annular body according to the present invention.
FIG. 2 is an enlarged sectional explanatory view of a main part of the same.
FIG. 3 is an enlarged cross-sectional view for explaining a state where the tube is mounted on the tube.
FIG. 4 is a longitudinal sectional view showing a state where the present invention is applied to a pipe connection part.
FIG. 5 is an enlarged sectional view showing a conventional low-loss water-head type annular body.
[Explanation of symbols]
Reference Signs List 10 low-loss water head type annular body 11 annular body 12, 13 fixing portion 14 fixing plate 15 fixing plate attaching concave portion 16, 17 water stopping ridge 20 bell mouth shape 21, 22 haunch portion 23, 23 'inner wall 24, 24' Tube 27 Smooth surface 28 Thin groove

Claims (2)

A low-loss head-type annular body which is attached for the purpose of stopping water over a part of the inner wall of the pipe and does not cause a substantial decrease in water supply capacity, wherein an end of the annular body in a flow direction is annular. Attach the body body, have a diameter larger than the water stopping ridge pressed against the inner wall of the pipe by the fixing plate, and have a bell mouth shape having a substantially crescent cross section, and fix the annular body to the inner wall of the pipe by the fixing plate. Characterized in that a haunch portion for compressing and fixing the bell mouth shape when pressed against a corner is provided at a corner of the fixing plate mounting concave portion. The annular body is arranged at the pipe connection part, and the annular body can be expanded and contracted and bent by expansion and contraction or refraction of the pipe connection part. To reduce the resistance of flowing water, the inner surface of the annular body that is in contact with the water flow is smoothened. 2. The low loss according to claim 1, wherein a thin groove in the circumferential direction is provided therein, and the outer surface of the annular body has a corrugated cross-sectional shape in which a portion corresponding to the thin groove on the inner surface is a peak and an adjacent portion is a valley. Hydrohead ring.

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