JP3866853B2 - Branch pipe - Google Patents

Description

【００３１】
上記の表１からわかるように、分流及び合流のいずれの場合も従来例に比べこの実施形態の方がエネルギー損失係数が小さい。
【００３２】
【発明の効果】
以上のように、この発明は各枝管片の大径シェルを、主管側シェル片と中径シェル側シェル片とを接合して形成したことにより、分流及び合流のいずれの場合も流体の方向転換が円滑に行われる。このため、補強部材の寸法を従来に比べて相当小形化しても分岐管全体の強度を従来と同様に維持することができる。また、上記の流体の方向転換の円滑化と補強部材の小形化とが相いまって、分流、合流いずれの場合にも分岐管における流体のエネルギー損失が著しく低減される。更に、補強部材が小形化されることにより、材料費及び分岐管の建造費が低減される。
【図面の簡単な説明】
【図１】（ａ） 第１実施形態の横断平面図
（ｂ） 同上の縦断正面図
【図２】（ａ） 従来例の応力分布図
（ｂ） 第１実施形態の場合の応力分布図
【図３】（ａ） 従来例の横断平面図
（ｂ） 同上の縦断正面図
【符号の説明】
１ 主管
１ａ 主管片
１ｂ 小径シェル
１ｃ 大径シェル
１Ａ 主管片
２ 枝管
２ａ 枝管片
２ｂ 小径シェル
２ｃ 中径シェル
２ｄ 大径シェル
２ｄ₁ 枝管側シェル片
２ｄ₂ 主管側シェル片
２Ａ 枝管片
３ 枝管
３ａ 枝管片
３ｂ 小径シェル
３ｃ 中径シェル
３ｄ 大径シェル
３ｄ₁ 枝管側シェル片
３ｄ₂ 主管側シェル片
３Ａ 枝管片
４ 枝管
４ａ 枝管片
４ｂ 小径シェル
４ｃ 中径シェル
４ｄ 大径シェル
４ｄ₁ 枝管側シェル片
４ｄ₂ 主管側シェル片
４Ａ 枝管片
５ 仮想球
６ 交截部
６ａ、６ｂ 交截部
７ 分岐点
８ 補強部材
８ａ 外周円弧部
８ｂ 内周円弧部
９ 接合箇所
１０、１１ 接合部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a branch pipe used for splitting or merging liquids in a hydraulic facility such as a hydraulic line of a hydroelectric power plant or a fluid machine.
[0002]
[Prior art]
In the hydraulic pipelines and liquid machines of hydroelectric power plants, the energy loss of the fluid generated inside the branch pipe is not negligible, and it is required to reduce this as much as possible.
[0003]
On the other hand, such a branch pipe is constituted by joining several pipe parts, but some reinforcing means must be applied in order to maintain a balance of forces caused by fluid pressure and the like at the joint. If the reinforcement is not appropriate, a high stress is generated in the structural portion of the branch pipe, which causes breakage.
[0004]
The characteristics of the energy loss of the branch pipe as described above or the force or stress generated in the joint are defined by the shape and structure of the branch pipe.
[0005]
The branch pipe of the conventional example shown in FIG. 3 (see Japanese Patent Publication No. 36-10880) is constructed by joining one main pipe 1 and two branch pipes 2 and 3 having a smaller diameter. Also, Ru mower when joining three branch pipes of the main pipe 1.
[0006]
The main pipe 1 is constituted by joining a cylindrical main pipe piece 1a and a conical main pipe piece 1A, and the conical main pipe piece 1A joins a conical small diameter shell 1b and a large diameter shell 1c without any step. Configured. The small-diameter shell 1b and the cylindrical main pipe piece 1a are joined without a step.
[0007]
Each of the main pipes 2 and 3 is configured by joining cylindrical branch pipe pieces 2a and 3a and conical branch pipe pieces 2A and 3A, and each of the conical branch pipe pieces 2A and 3A has a conical shape. The small-diameter shells 2b and 3b, the medium-diameter shells 2c and 3c, and the large-diameter shells 2d and 3d are joined without any step. The small-diameter shells 2b and 3b and the cylindrical branch pipe pieces 2a and 3a are joined without a step.
[0008]
The conical main pipe piece 1A and the two conical branch pipe pieces 2A and 3A are formed in a shape circumscribing one common phantom sphere 5 having a diameter larger than the diameter of the main pipe piece 1A. the lateral pipe pieces 2A, large diameter shell 2d of 3A, with交截section 6 is generated between 3d each other, main piece 1A and two branch pipes pieces 2A, tripartite 3A is Ru are gaps without bonding.
[0009]
A crescent plate-like (hereinafter referred to as “crescent shape” or “crescent shape”) reinforcing member 8 is sandwiched and joined to the mating portion 6. The inner peripheral circular arc portion 8b of the reinforcing member 8 protrudes into the branch pipe, and both ends thereof are at both ends of the mating portion 6, that is, the joint portion 9 of the main pipe piece 1A and the two branch pipe pieces 2A and 3B. Reach.
[0010]
With the structure as described above, energy loss of the fluid generated inside the branch pipe can be reduced, and the reinforcing member 8 can mainly reduce the amount of material used because only the tensile stress is generated in the cross section. .
[0011]
In the branch pipe of the type attached to the intersection 6 of the two adjacent branch pipes 2 and 3 like the reinforcing member 8 described above, the tensile force or the like resulting from the fluid pressure is applied to the reinforcing member 8 on the plate. Since it acts in the thickness direction, there is a risk that cracks such as lamellar tears may occur, and in order to prevent this, the material is not a general steel material, but has a performance that can withstand the above mechanical conditions like a so-called lamellar steel material Things are used.
[0012]
[Problems to be solved by the invention]
In the conventional branch pipe, the crescent-shaped reinforcing member 8 is provided at the crossing portion 6 between the large diameter shells 2d and 3d of the two adjacent branch pipes 2 and 3, and both ends thereof are the main pipe pieces 1A and 2A. The junction 9 of the three branches 2A and 3A is reached. For this reason, especially when the pipe diameter is large, the dimension of the reinforcing member 8 is large, and the material cost is high. In addition, when the fluid pressure is high, the material used is extremely thick, so that there is a problem that the material cost is further increased and the construction cost of the branch pipe is remarkably high.
[0013]
As a measure for reducing the material cost, a method of constructing the reinforcing member 8 by joining a plurality of small members is conceivable, but an increase in joining cost is inevitable, so it is not an effective measure.
[0014]
On the other hand, reducing the energy loss of the fluid in the branch pipe is always a challenge to be pursued, and for example, it may be used for both shunting and merging such as the branch pipe used in the hydraulic pipe of a pumped storage power plant. In any case, there is a strong demand for less energy loss of the fluid in any case.
[0015]
The object of the present invention is to reduce the size of the crescent-shaped reinforcing material as compared with the conventional one, reduce the material cost and the construction cost of the branch pipe, and at the inside of the branch pipe at the time of diversion and merge. It is an object of the present invention to provide a branch pipe capable of reducing the energy loss of a generated fluid as compared with the conventional one.
[0016]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention comprises one main pipe and a plurality of branch pipes joined to the main pipe, and the main pipe and the branch pipe have one common diameter larger than the main pipe. A conical main pipe piece circumscribing the phantom sphere and a conical branch pipe piece, wherein the main pipe piece is formed by joining a large diameter shell and a small diameter shell circumscribing the phantom sphere; The pipe piece is formed by joining a large-diameter shell, a medium-diameter shell, and a small-diameter shell, and the large-diameter shell of each branch pipe piece is an intersection formed between the large-diameter shells of other adjacent branch pipe pieces. In the branch pipe having a collar portion, the main pipe piece and the large-diameter shell of each branch pipe piece are joined, and a crescent-shaped reinforcing member projecting inwardly is provided in the mating part. the large diameter shell of the branch stub, and main side shell pieces circumscribing the virtual sphere which is joined to the main pipe piece, the in diameter Shi Is constructed by joining a branch pipe side shell pieces to be joined and Le, said reinforcing member is provided only on交截portion of the branch pipe side shell pieces, both ends of the reinforcing member that branch pipe side shell piece It was set as the structure which reached the both ends of the mating part .
[0017]
[Action]
According to the present invention, the large-diameter shell of the branch pipe piece of each branch pipe is configured by joining the main pipe-side shell piece and the medium-diameter shell-side shell piece. In the case of merging, the direction change angle of the flow path from each branch pipe to the main pipe becomes gradual, and the direction change of the fluid is smoothly achieved.
[0018]
On the other hand, according to the structure as described above, the generated stress in the vicinity of both ends of the reinforcing member is not large, and as a result, even if the reinforcing member is considerably reduced in size compared to the conventional structure, the strength of the entire branch pipe is not affected.
[0019]
Incidentally, the reinforcing member is too small, undesirably lose rectifying effect, if the two end points is the extent to reach the junction箇plants of both shell piece has a rectifying effect, the increase in energy loss Can be avoided.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
The branch pipe of the first embodiment shown in FIG. 1 is formed by joining a main pipe 1 and two branch pipes 2 and 3 having a smaller diameter than the main pipe 1 as in the above-described conventional example. The main pipe 1 is configured by joining a cylindrical main pipe 1a and a conical main pipe piece 1A, and the conical main pipe piece 1A joins a conical small diameter shell 1b and a large diameter shell 1c without any step. Configured. The small-diameter shell 1b and the cylindrical main pipe piece 1a are joined without a step.
[0021]
Each of the branch pipes 2 and 3 is formed by joining cylindrical branch pipe pieces 2a and 3a and conical branch pipe pieces 2A and 3A, respectively. The conical small-diameter shells 2b and 3b, the medium-diameter shells 2c and 3c, and the large-diameter shells 2d and 3d are joined without any step. The small-diameter shells 2b and 3b and the cylindrical branch pipe pieces 2a and 3a are joined without a step.
[0022]
The main pipe piece 1A and the two branch pipe pieces 2A, 3A are formed in a shape circumscribing one common phantom sphere 5 having a diameter larger than the diameter of the main pipe piece 1A, whereby the branch pipe piece 2A. large diameter shell 2d of 3A,交截portion 6a between 3d each other, with 6b occurs, main piece 1A and two branch pipes pieces 2A, tripartite 3A is Ru are gaps without bonding.
[0023]
The above configuration is the same as the conventional example, but there is a difference in the following configuration. That is, the first difference is that the branch stub 2A above, the large diameter shell 2d of 3A, 3d are lateral pipe pieces 2A, branch pipe side shell piece 2d ₁ to be joined middle diameter shell 2c of 3A, 3c and 3d ₁ and the main pipe side shell pieces 2d ₂ and 3d ₂ to be joined to the large diameter shell 1c of the main pipe piece 1A are joined at the joining portions 10 and 11 without any step. These branch pipe side shell pieces 2d ₁ , 3d ₁ have crossed portions 6a, and the main pipe side shell pieces 2d ₂ , 3d ₂ have crossed portions 6b.
[0024]
The second difference is the size of the reinforcing member 8. In other words, the reinforcing member 8 in this case is the same as the conventional one in that it has a crescent shape, but its size is considerably smaller than that of the conventional one, and the outer peripheral arc portion 8a has the branch pipe described above. The side shell pieces 2d ₁ and 3d ₁ are clamped and joined to the crossing portion 6a. Arc-shaped inner peripheral portion 8b of the reinforcing member 8 protrudes into the interior of the branch pipe, both ends of the both ends branch pipe side shell pieces 2d _1, 3d ₁ of交截portion 6a, i.e. the branch pipe side shell pieces 2d _1, 3d ₁ And the main pipe side shell pieces 2d ₂ and 3d _2, and the joint portions 9a and 9a at the two ends of the joining portion 6a.
[0026]
In FIG. 1, both end points of the crossed portion 6b of the large-diameter shells 2d ₂ and 3d ₂ are denoted by reference numerals 9b and 9b.
[0027]
By comprising as mentioned above, the dimension of the reinforcing member 8 becomes a considerably small dimension compared with a prior art example. FIG. 2A shows the stress distribution due to the fluid pressure flowing in the conventional example when the reinforcing member 8 having a long dimension of the conventional example is used, and FIG. 2B shows the dimension of the above embodiment. It is a stress distribution figure by the fluid pressure which flows in the embodiment at the time of using the short reinforcement member 8 of this. These stress distribution diagram, Ru der those expressed by the ratio (σ / σ ₀₎ the stress sigma of each part of the reinforcing member 8 with respect to the reference stress (σ ₀ = 1).
[0028]
When both are compared, it can be confirmed that there is no significant increase in stress even when the reinforcing material 8 having a short size is used as in this embodiment. In addition, in the conventional case, stress is generated in the end of the reinforcing member 8 in a long range up to the joint 9, whereas in this embodiment, stress is applied in a short range up to the joint 9 a. It can be confirmed that it is sufficiently small. That is, it can be said that the reinforcing member 8 according to the present invention does not deteriorate the stability of the branch pipe although the size is considerably smaller than that of the conventional member.
[0029]
In addition, the energy loss coefficient in the branch pipe is divided into a case where the flow direction is the direction from the main pipe 1 to the branch pipes 2 and 3, that is, a branch flow, and a case where the flow direction is from the branch pipes 2 and 3 to the main pipe 1. The examination results are shown in Table 1.
[0030]
[Table 1]

[0031]
As can be seen from Table 1 above, the energy loss coefficient of this embodiment is smaller than that of the conventional example in both cases of diversion and merging.
[0032]
【The invention's effect】
As described above, according to the present invention, the large-diameter shell of each branch pipe piece is formed by joining the main pipe-side shell piece and the medium-diameter shell-side shell piece. Conversion is done smoothly. For this reason, even if the size of the reinforcing member is considerably reduced compared to the conventional size, the strength of the entire branch pipe can be maintained as in the conventional case. In addition, the smooth transition of the direction of the fluid and the downsizing of the reinforcing member are combined, so that the energy loss of the fluid in the branch pipe is remarkably reduced in both cases of diversion and merging. Furthermore, since the reinforcing member is reduced in size, the material cost and the construction cost of the branch pipe are reduced.
[Brief description of the drawings]
1A is a cross-sectional plan view of the first embodiment. FIG. 1B is a longitudinal front view of the same. FIG. 2A is a stress distribution diagram of a conventional example. FIG. 1B is a stress distribution diagram of the first embodiment. Fig. 3 (a) Cross-sectional plan view of a conventional example (b) Vertical front view of the same
1 Main pipe 1a Main pipe piece 1b Small diameter shell 1c Large diameter shell 1A Main pipe piece 2 Branch pipe 2a Branch pipe piece 2b Small diameter shell 2c Medium diameter shell 2d Large diameter shell 2d ₁ Branch pipe side shell piece 2d ₂ Main pipe side shell piece 2A Branch pipe piece 3 Branch pipe 3a Branch pipe piece 3b Small diameter shell 3c Medium diameter shell 3d Large diameter shell 3d ₁ Branch pipe side shell piece 3d ₂ Main pipe side shell piece 3A Branch pipe piece 4 Branch pipe 4a Branch pipe piece 4b Small diameter shell 4c Medium diameter shell 4d Large diameter shell 4d ₁ Branch pipe side shell piece 4d ₂ Main pipe side shell piece 4A Branch pipe piece 5 Virtual sphere 6 Intersection 6a, 6b Intersection 7 Branch point 8 Reinforcement member 8a Outer circular arc 8b Inner circular arc 9 Joining Location 10, 11 Joint

Claims (1)

It consists of one main pipe (1) and a plurality of branch pipes (2, 3) joined thereto, and the main pipe (1) and the branch pipes (2, 3) are larger than the main pipe (1). The main pipe piece (1A) includes a truncated cone-shaped main pipe piece (1A) and a truncated cone-shaped branch pipe piece (2A, 3A) circumscribing one common phantom sphere (5) having a diameter. A large-diameter shell (1c) and a small-diameter shell (1b) circumscribing the phantom sphere (5) are joined, and the branch pipe pieces (2A, 3A) are large-diameter shells (2d, 3d), medium-diameter shells. (2c, 3c) and a small-diameter shell (2b, 3b) are joined together, and the large-diameter shell (2d, 3d) of each branch pipe piece (2A, 3A) is adjacent to the adjacent branch pipe piece (2A, A crescent-plate-shaped reinforcing member having a mating portion (6) generated between the large-diameter shell (2d, 3d) of 3A) and projecting inside the mating portion (6) In the branch pipe formed by providing a 8),
The large diameter shell (2d, 3d) of the branch pipe piece (2A, 3A) is a main pipe side shell piece circumscribing the phantom sphere (5) joined to the large diameter shell (1c) of the main pipe piece (1A). (2d ₂ , 3d ₂ ) and a branch pipe side shell piece (2d ₁ , 3d ₁ ) joined to the medium diameter shell (2c, 3c) are joined together, and the reinforcing member (8) is交截portion of the branch pipe side shell piece _{(2d 1, 3d 1) (} 6a) only provided et al is, exchange of the both ends the branch pipe side shell piece of the reinforcing member of that _{(8) (2d 1, 3d} 1) A branch pipe reaching both ends of the buttocks (6a).

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