JP2012177443A - Piping structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piping structure capable of easily suppressing large pressure variation in branched pipes at low cost irrespective of flowing speed of fluid flowing in a mother pipe.SOLUTION: In the piping structure 100 in which the branched pipe 112 is connected to the mother pipe 111 such that the axial direction of the branched pipe 112 intersects with the axial direction of the mother pipe 111, a cover member 113 is arranged in the opening 112a of the branched pipe 112 such that the shape of the opening 112a portion of the branched pipe 112 becomes a linear asymmetrical shape over a whole length of a diametrical line L when the diametrical line L of the opening 112a portion of the branched pipe 112 in a direction parallel to the axial line of the mother pipe 111 is the symmetrical axis.

Description

  The present invention relates to a piping structure in which a branch pipe is connected to a mother pipe so that the axial direction of the branch pipe intersects the axial direction of the mother pipe.

  For example, a pipe in which a branch pipe is connected to the main pipe so that the axial direction of the branch pipe intersects the axial direction of the main pipe, such as a T-shaped pipe structure in which a drain pipe is connected to a steam pipe through which steam flows In the structure, a large pressure fluctuation occurs in the branch pipe due to the flow velocity of the fluid flowing inside the mother pipe, and various devices (for example, a drain valve) provided in the branch pipe are damaged. There is. This is because an vortex having a frequency f corresponding to the diameter of the branch pipe and the flow velocity of the fluid is generated in the opening portion where the fluid flowing in the mother pipe connects to the branch pipe, and the frequency f becomes the length of the branch pipe. This is because it corresponds to the corresponding air column resonance frequency fp of the branch pipe.

  For this reason, conventionally, for example, (1) a branch pipe having a diameter or a length that does not match the frequency f and the air column resonance frequency fp is connected based on the flow velocity of the fluid flowing in the mother pipe. Or (2) the generation of the vortex is suppressed by processing the peripheral edge of the connecting portion between the mother pipe and the branch pipe to have a rounded shape without making a corner.

JP 2008-256130 A

  However, in the above-described means (1), if the fluid is circulated in the mother pipe at a flow rate different from the initially planned flow rate, the frequency f and the air column resonance frequency fp coincide with each other. In some cases, the above-described means (2) is very time-consuming to process, resulting in an increase in cost.

  In view of the above, an object of the present invention is to provide a piping structure that can easily suppress a large pressure fluctuation in the branch pipe at a low cost regardless of the flow velocity of the fluid flowing in the mother pipe.

  The piping structure according to the first invention for solving the above-mentioned problem is a piping structure in which the branch pipe is connected to the mother pipe so that the axial direction of the branch pipe intersects the axial direction of the mother pipe. In this case, when the diameter line of the opening of the branch pipe in the direction parallel to the axial direction of the mother pipe is set as the axis of symmetry, the shape of at least a part of the opening of the branch pipe becomes a non-symmetrical shape. The opening of the branch pipe is provided with an asymmetric member.

  The piping structure according to a second aspect of the present invention is the piping structure according to the first aspect, wherein the asymmetric member is disposed at the opening of the branch pipe so that the asymmetric member is located at least upstream in the flow direction of the fluid flowing through the mother pipe. It is provided.

  A piping structure according to a third invention is characterized in that, in the first or second invention, the asymmetric member includes a cover member for closing a part of the opening of the branch pipe. To do.

  The piping structure according to a fourth aspect of the present invention is the piping structure according to any one of the first to third aspects, wherein the asymmetrical member is arranged so that a plurality of ends protrude from the inside of the mother pipe. Protruding members provided along the periphery of the opening and having different height positions projecting inside the mother pipe at positions that are symmetric when the diameter line is a symmetric axis. Features.

  According to the piping structure according to the present invention, the separation point of the opening of the branch pipe with respect to the fluid flow in the mother pipe becomes non-axisymmetric when the diameter line is the axis of symmetry, so the diameter of the opening of the branch pipe Since the vortex cycle is disturbed over the entire length of the line, periodic vortices are less likely to occur at the opening of the branch tube, and air column resonance is very unlikely to occur in the branch tube. As a result, large pressure fluctuations in the branch pipe can be easily suppressed at low cost regardless of the flow rate of the fluid.

It is a schematic structure figure of the important section of a 1st embodiment of piping structure concerning the present invention. It is a schematic structural drawing of the principal part of 2nd embodiment of the piping structure which concerns on this invention. It is a schematic structural drawing of the principal part of 3rd embodiment of the piping structure which concerns on this invention. It is a schematic structural drawing of the principal part of 4th embodiment of the piping structure which concerns on this invention. It is a schematic structural drawing of the principal part of 5th embodiment of the piping structure which concerns on this invention.

  Embodiments of the piping structure according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments described with reference to the drawings.

[First embodiment]
A first embodiment of the piping structure according to the present invention will be described with reference to FIG.

  As shown in FIG. 1, the piping structure according to the present embodiment is a piping structure 100 in which the branch pipe 112 is connected to the mother pipe 111 so that the axial direction of the branch pipe 112 intersects the axial direction of the mother pipe 111. When the diameter line L of the opening 112a of the branch pipe 112 in the direction parallel to the axial direction of the mother pipe 111 is taken as the axis of symmetry, the shape of the opening 112a portion of the branch pipe 112 is non-symmetrical over the entire length of the diameter line L. A cover member 113 serving as an asymmetric member is provided in the opening 112a of the branch pipe 112 so as to have a shape.

  The cover member 113 has a semi-cylindrical block shape formed so as to block a part of the opening 112a of the branch pipe 112, and depends on the flow of the fluid 1 flowing through the mother pipe 111. The end portion is formed in a shape that does not protrude into the mother pipe 111 so as not to inhibit the flow of the fluid 1 while having sufficient rigidity without causing stress vibration.

  Such a piping structure 100 can be easily configured by simply attaching the cover member 113 having a simple structure to the opening 112 a of the branch pipe 112.

  In such a piping structure 100 according to this embodiment, the shape of the opening 112a portion of the branch pipe 112 becomes a non-axisymmetric shape by the cover member 113 when the diameter line L is an axis of symmetry. That is, the separation point with respect to the flow of the fluid 1 when the diameter line L is the axis of symmetry is axisymmetrical over the entire length of the opening 112a of the branch pipe 112 in the flow direction. The period of the vortex is disturbed over the entire length of the diameter line L of the opening 112a of 112.

  For this reason, in the piping structure 100 according to the present embodiment, periodic vortices are unlikely to occur in the opening 112a portion of the branch pipe 112, so that air column resonance is extremely unlikely to occur in the branch pipe 112.

  Therefore, according to the piping structure 100 according to the present embodiment, large pressure fluctuations in the branch pipe 112 can be easily suppressed at a low cost regardless of the flow rate of the fluid 1.

[Second Embodiment]
A second embodiment of the piping structure according to the present invention will be described with reference to FIG. However, the same parts as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment, and the description overlapping the description in the above-described embodiment is omitted.

  As shown in FIG. 2, the piping structure according to the present embodiment is a piping structure 200 in which the branch pipe 112 is connected to the mother pipe 111 so that the axial direction of the branch pipe 112 intersects the axial direction of the mother pipe 111. When the diameter line L of the opening 112a of the branch pipe 112 in the direction parallel to the axial direction of the mother pipe 111 is a symmetric axis, the shape of the opening 112a portion of the branch pipe 112 is the fluid 1 that circulates in the mother pipe 111. A cover member 213 serving as an asymmetric member is provided on the upstream side in the flow direction of the opening 112a of the branch pipe 112 so as to be axisymmetrical on the upstream side in the flow direction.

  The cover member 213 is a quadrant (fan) column shape formed so as to block a part of the opening 112a of the branch pipe 112 that is 1/2 of the upstream in the flow direction (1/4 of the opening 112a). And has sufficient rigidity so as not to cause stress vibration due to the flow of the fluid 1 flowing in the mother pipe 111, and so as not to disturb the flow of the fluid 1. The end is formed in a shape that does not protrude into the interior of the housing.

  Such a pipe structure 200 can be easily obtained by simply attaching the cover member 213 having a simple structure to the opening 112a of the branch pipe 112, as in the case of the pipe structure 100 according to the first embodiment described above. Can be configured.

  That is, in the piping structure 100 according to the first embodiment described above, the semi-cylindrical cover member 113 is applied so that the shape of the opening 112a portion of the branch pipe 112 is non-symmetrical over the entire length in the flow direction. However, in the piping structure 200 according to this embodiment, a quadrant (fan) column shape is used so that the shape of the opening 112a portion of the branch pipe 112 is non-symmetrical only on the upstream side in the flow direction. The cover member 213 is applied.

  In such a piping structure 200 according to the present embodiment, the shape of the opening 112a portion of the branch pipe 112 on the upstream side in the flow direction is not when the diameter line L is a symmetric axis by the cover member 213. The separation point with respect to the flow of the fluid 1 when the diameter line L is an axis of symmetry is axisymmetric on the upstream side in the flow direction of the opening 112a of the branch pipe 112. Therefore, the period of the vortex can be disturbed over the entire length of the diameter line L of the opening 112a of the branch pipe 112.

  For this reason, in the piping structure 200 according to the present embodiment, as in the case of the piping structure 100 according to the first embodiment described above, periodic vortices are unlikely to occur in the opening 112a portion of the branch pipe 112. As a result, air column resonance hardly occurs in the branch pipe 112.

  Therefore, according to the piping structure 200 according to the present embodiment, as in the case of the piping structure 100 according to the first embodiment described above, a large pressure fluctuation in the branch pipe 112 is caused regardless of the flow rate of the fluid 1. It can be easily suppressed at low cost.

[Third embodiment]
A third embodiment of the piping structure according to the present invention will be described with reference to FIG. However, the same parts as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment, and the description overlapping the description in the above-described embodiment is omitted.

  As shown in FIG. 3, the piping structure according to the present embodiment is a piping structure 300 in which the branch pipe 112 is connected to the mother pipe 111 so that the axial direction of the branch pipe 112 intersects the axial direction of the mother pipe 111. When the diameter line L of the opening 112a of the branch pipe 112 in the direction parallel to the axial direction of the mother pipe 111 is a symmetric axis, the shape of the opening 112a portion of the branch pipe 112 is the fluid 1 that circulates in the mother pipe 111. A cover member 313 serving as an asymmetric member is provided on the upstream side in the flow direction of the opening 112a of the branch pipe 112 so as to have a non-symmetrical shape on the upstream side in the flow direction.

  The cover member 313 is a quadrant (fan) plate type formed so as to block a part of the opening 112a of the branch pipe 112 that is 1/2 of the upstream in the flow direction (1/4 of the opening 112a). And is fixed to the inner peripheral surface of the branch pipe 112 by means of a support bracket 313a, so that stress vibration due to the flow of the fluid 1 flowing through the mother pipe 111 does not occur. In addition, it has a sufficient rigidity and is formed in a shape that does not protrude into the mother pipe 111 so as not to hinder the flow of the fluid 1.

  Such a piping structure 300 can be easily configured by simply attaching the cover member 313 having a simple structure to the opening 112a of the branch pipe 112 via the support bracket 313a having a simple structure.

  That is, in the piping structure 200 according to the second embodiment described above, the quadrant (fan) column-shaped block-shaped cover member 213 is attached to the branch pipe 112, but the piping according to this embodiment is used. In the structure 300, a quadrant (fan) column-shaped plate-shaped cover member 313 is attached to the branch pipe 112 via a support bracket 313a.

  Therefore, according to the piping structure 300 according to the present embodiment, as in the case of the piping structure 200 according to the second embodiment described above, a large pressure fluctuation in the branch pipe 112 is caused regardless of the flow rate of the fluid 1. It can be easily suppressed at low cost.

[Fourth embodiment]
A fourth embodiment of the piping structure according to the present invention will be described with reference to FIG. However, the same parts as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment, and the description overlapping the description in the above-described embodiment is omitted.

  As shown in FIG. 4, the piping structure according to the present embodiment is a piping structure 400 in which the branch pipe 112 is connected to the mother pipe 111 so that the axial direction of the branch pipe 112 intersects the axial direction of the mother pipe 111. When the diameter line L of the opening 112a of the branch pipe 112 in the direction parallel to the axial direction of the mother pipe 111 is a symmetric axis, the shape of the opening 112a portion of the branch pipe 112 is the fluid 1 that circulates in the mother pipe 111. A cover member 413 serving as an asymmetric member is provided on the upstream side in the flow direction of the opening 112a of the branch pipe 112 so as to be axisymmetrical in the middle of the flow direction.

  The cover member 413 has a semi-cylindrical block shape formed so as to close the upstream side in the flow direction of the opening 112a of the branch pipe 112, and an end surface located on the downstream side in the flow direction has the diameter line. It is formed into a wave shape so as to have a non-symmetrical shape when L is a symmetric axis, and has sufficient rigidity that does not cause stress vibration due to the flow of the fluid 1 flowing through the mother pipe 111. In addition, an end portion is formed in a shape that does not protrude into the mother pipe 111 so as not to hinder the flow of the fluid 1.

  In such a piping structure 400, the cover member 413 having a simple structure is attached to the opening 112a of the branch pipe 112, similarly to the piping structures 100 and 200 according to the first and second embodiments described above. It can be configured simply.

  That is, in the piping structure 100 according to the first embodiment described above, the semi-cylindrical cover member 113 is provided so that the shape of the opening 112a portion of the branch pipe 112 is non-symmetrical over the entire length in the flow direction. Although arranged in the branch pipe 112, in the piping structure 400 according to the present embodiment, the shape in the middle of the flow direction of the opening 112a portion of the branch pipe 112 is asymmetric so as to be non-symmetrical. A semi-cylindrical cover member 413 is disposed on the upstream side in the flow direction so that the formed end face faces the downstream side in the flow direction.

  In such a piping structure 400 according to the present embodiment, the shape in the middle of the flow direction of the opening 112a portion of the branch pipe 112 is not when the diameter line L is a symmetric axis by the cover member 413. The separation point with respect to the flow of the fluid 1 when the diameter line L is the axis of symmetry is axisymmetrical in the middle of the flow direction of the opening 112a of the branch pipe 112. Therefore, the period of the vortex can be disturbed over the entire length of the diameter line L of the opening 112a of the branch pipe 112.

  For this reason, in the piping structure 400 according to the present embodiment, as in the piping structures 100, 200, 300 according to the first to third embodiments described above, the opening 112a portion of the branch pipe 112 is periodically formed. Therefore, air column resonance is hardly generated in the branch pipe 112.

  Therefore, according to the piping structure 400 according to the present embodiment, the inside of the branch pipe 112 regardless of the flow rate of the fluid 1, as in the case of the piping structures 100, 200, and 300 according to the first to third embodiments described above. The large pressure fluctuations at can be easily suppressed at low cost.

[Fifth embodiment]
A fifth embodiment of the piping structure according to the present invention will be described with reference to FIG. However, the same parts as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment, and the description overlapping the description in the above-described embodiment is omitted.

  As shown in FIG. 5, the piping structure according to this embodiment is a piping structure 500 in which the branch pipe 112 is connected to the mother pipe 111 so that the axial direction of the branch pipe 112 intersects the axial direction of the mother pipe 111. When the diameter line L of the opening 112a of the branch pipe 112 in the direction parallel to the axial direction of the mother pipe 111 is a symmetric axis, the shape of the opening 112a portion of the branch pipe 112 is the fluid 1 that circulates in the mother pipe 111. A plurality of rod-like projecting members 513 serving as asymmetric members are provided on the upstream side in the flow direction at the periphery of the opening 112a of the branch pipe 112 so as to be non-axisymmetric on the upstream side in the flow direction.

  The projecting member 513 has a peripheral edge on the upstream side in the flow direction of the opening 112a of the branch pipe 112 so that the end portion protrudes inside the mother pipe 111 in the axial direction along the axial direction of the branch pipe 112. The openings 112a are arranged in the circumferential direction so that the height positions projecting inside the mother pipe 111 at positions symmetrical with respect to the diameter line L are different from each other without being coincident with each other. It is set irregularly and has sufficient rigidity so as not to cause stress vibration due to the flow of the fluid 1 flowing in the mother pipe 111, and the flow of the fluid 1 flowing in the mother pipe 111 is increased. The amount of protrusion does not hinder.

  Such a piping structure 500 can be easily configured by simply attaching a plurality of protruding members 513 having a simple structure to the opening 112 a of the branch pipe 112.

  That is, in the piping structures 100, 200, and 300 according to the first to fourth embodiments described above, the shape of the opening 112a portion of the branch pipe 112 when the diameter line L is an axis of symmetry is axisymmetric. As shown, the cover members 113, 213, 313, and 413 are arranged flush with the opening 112a of the branch pipe 112. However, in the piping structure 500 according to the present embodiment, the diameter line L is the axis of symmetry. The protruding member 513 is disposed so as to protrude from the opening 112a of the branch pipe 112 into the mother pipe 111 so that the shape of the opening 112a portion of the branch pipe 112 is non-symmetrical.

  In such a piping structure 500 according to the present embodiment, the shape of the opening 112a portion of the branch pipe 112 on the upstream side in the flow direction is not when the diameter line L is a symmetric axis by the protruding member 513. Not only has a line-symmetric shape, but also irregular irregularities with respect to the inside of the mother pipe 111, that is, a separation point with respect to the flow of the fluid 1 when the diameter line L is an axis of symmetry. And irregular turbulence is positively generated in the fluid 1, so that the generation of vortices is irregular and the vortex period is disturbed over the entire length of the diameter line L of the opening 112a of the branch pipe 112. be able to.

  For this reason, in the piping structure 500 according to the present embodiment, in the opening 112a portion of the branch pipe 112, as in the case of the piping structures 100, 200, 300, 400 according to the first to fourth embodiments described above. Since periodic vortices are less likely to occur, air column resonance is very unlikely to occur in the branch pipe 112.

  Therefore, according to the piping structure 200 according to the present embodiment, as in the case of the piping structures 100, 200, 300, and 400 according to the first to fourth embodiments described above, the branch pipe regardless of the flow rate of the fluid 1. Large pressure fluctuations in 112 can be easily suppressed at low cost.

[Other Embodiments]
In the piping structures 100, 200, 300, and 400 according to the first to fourth embodiments described above, the cover members 113, 213, 313, and 413 are branched when the diameter line L is an axis of symmetry. If the opening 112a of the branch pipe 112 is provided in the opening 112a of the branch pipe 112 so that the shape of the opening 112a portion of the pipe 112 is axisymmetric, the direction (position) of the branch pipe 112 with respect to the circumferential direction is particularly limited. is not.

  However, in the cover members 213 and 313 of the piping structures 200 and 300 according to the second and third embodiments described above, the fluid 1 flowing in the mother pipe 111 is positioned upstream in the flow direction. If the direction (position) with respect to the circumferential direction of the branch pipe 112 is set, the above-described effects can be achieved as compared with the case where the direction (position) with respect to the circumferential direction of the branch pipe 112 is set so as to be located downstream in the flow direction. This is very preferable because it becomes more noticeable.

  In the piping structure 500 according to the fifth embodiment described above, the protruding member 513 is provided over the entire peripheral length (1/2 of the circumference) on the upstream side in the flow direction of the opening 112a of the branch pipe 112. However, the present invention is not limited to this, and as another embodiment, for example, the protruding member 513 is a part of the peripheral edge of the opening 112a of the branch pipe 112 on the upstream side in the flow direction (for example, the circumference Of the opening 112a of the branch pipe 112 over the entire circumference (circumferential overall length) of the branch pipe 112.

  Further, as another embodiment, for example, a protruding member is further provided on the cover members 113, 13, 313, 413 in the piping structures 100, 200, 300, 400 according to the first to fourth embodiments described above. It is also possible to make it.

  Since the piping structure according to the present invention can easily suppress large pressure fluctuations in the branch pipe regardless of the flow rate of the fluid at a low cost, it can be used extremely beneficially in various industries.

DESCRIPTION OF SYMBOLS 1 Fluid 100 Piping structure 111 Mother pipe 112 Branch pipe 112a Opening 113 Cover member 200 Piping structure 213 Cover member 300 Piping structure 313 Cover member 313a Support bracket 400 Piping structure 413 Cover member 500 Piping structure 513 Projection member L Diameter wire

Claims (4)

In the piping structure in which the branch pipe is connected to the mother pipe so as to intersect the axial direction of the branch pipe with respect to the axial direction of the mother pipe,
When the diameter line of the opening of the branch pipe in a direction parallel to the axial direction of the mother pipe is a symmetric axis, the shape of at least a part of the opening portion of the branch pipe is a non-symmetrical shape. A piping structure characterized in that an asymmetric member is provided in the opening of the branch pipe. In the piping structure according to claim 1,
The piping structure, wherein the asymmetric member is provided at the opening of the branch pipe so as to be positioned at least upstream in the flow direction of the fluid flowing through the mother pipe. In the piping structure according to claim 1 or claim 2,
The piping structure, wherein the asymmetric member includes a cover member that closes a part of the opening of the branch pipe. In the piping structure according to any one of claims 1 to 3,
A position where the asymmetry member is provided along the periphery of the opening of the branch pipe so that a plurality of ends protrude from the inside of the mother pipe, and is symmetric when the diameter line is a symmetric axis A piping structure characterized by comprising projecting members having different height positions projecting inside the mother pipe.

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