JP3634025B2 - Header manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a header, and more particularly to a method for producing a header that can be suitably used in a closed cooling tower.
[0002]
[Prior art]
In general, a closed cooling tower is provided with an upper water tank 2 above a tower body 1 as shown in a semi-sectional view in FIG. 4, and a plurality of packing material units 3 arranged vertically below the upper water tank 2. The conduit 4 for circulating the water to be cooled is disposed between the filler units 3, and the end of the conduit 4 is connected to the branch pipe 6 of the header (manifold) A.
[0003]
[Problems to be solved by the invention]
By the way, the header A has been conventionally manufactured as follows.
That is, a plurality of through holes are formed at predetermined intervals along the longitudinal direction of the main pipe 5 formed into a tubular shape, and the end portions of the branch pipes 6 are inserted into the respective through holes after the end portions of the branch pipes 6 are fitted. The outer periphery and the periphery of the through hole were welded. However, in the case of this conventional manufacturing method, when the through-holes are formed in the main pipe 5 at predetermined intervals, the positioning cannot be performed accurately, and the welding work may be time-consuming. Further, due to the distortion generated at the time of welding, the protruding direction (angle) of each branch pipe 6 may not be constant, and the connection to the conduit 4 may not be achieved.
[0004]
The present invention solves such a problem, and provides a method for producing a header that can be easily formed and can accurately project the projection angle, size, etc. of each branch pipe.
[0005]
[Means for Solving the Problems]
The present invention is to form a main pipe by bending a flat strip, and to manufacture a header having a plurality of branch pipes projecting from the main pipe, first, the strip along the longitudinal direction of the strip A plurality of through holes are formed at predetermined intervals. Next, end portions of the branch pipes prepared in advance are fitted into the respective through holes from one side of the band plate, and the outer circumferences of the end portions of the respective branch pipes protruding to the back side of the band plate and the peripheral portions of the through holes Weld. Therefore, the main plate is formed by bending the side edge in the longitudinal direction of the strip to which the branch pipe is connected to the back side of the strip and then welding the side edges of the strip together.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view of a process of drilling a through hole in a band plate, FIG. 2 is a sectional view of a process of welding after inserting an end of a branch pipe into the through hole, and FIG. 3 is a header obtained by the present invention. In the figure, reference numeral 5a denotes a flat strip, 5 denotes a main pipe, and 6 denotes a branch pipe.
[0007]
The band plate 5a is made of a metal plate such as steel or copper. In the present invention, the position where the through hole 51 is drilled in the longitudinal direction in the flat band plate 5a is marked, and a drilling machine or the like is used. A plurality of through holes 51 are formed in the belt plate 5a. At this time, a folding line b that is continuous or intermittent in the longitudinal direction is preferably engraved on the strip 5a.
[0008]
Therefore, a required number of metal branch pipes 6 are prepared. As shown in FIG. 2, the branch pipe 6 has a flange 61 at one end portion, and a small diameter portion 62 whose outer diameter is reduced with a step at the other end portion. The small diameter portion 62 of the branch pipe 6 is fitted into the through hole 51 from one side of the strip 5a, and the outer periphery of the end of the branch pipe 6 protruding to the back side of the strip 5a and the peripheral edge of the through hole 51 are welded. To do. This operation is sequentially repeated to connect the branch pipes 6 to the respective through holes 51.
[0009]
Next, the strip 5a to which the branch pipe 6 is connected is bent along the folding line b, and the side edges 52, 52 in the longitudinal direction of the strip are abutted and welded. Thus, the main pipe 5 having a square section is formed from the flat strip 5a, and the header A in which a plurality of branch pipes 6 project from the main pipe 5 is manufactured. Since the header A according to the manufacturing method of the present invention is accurate in the protruding angle, position size, and the like of the branch pipe 6, the header A can be easily connected to the conduit 4 when used in a hermetic cooling tower. Although FIG. 3 shows an example in which the strip 5a is bent into a square to form the main pipe 5, the present invention is not limited to this. The cross-sectional shape of the main pipe 5 can be formed into a hexagon, an octagon, or the like.
[0010]
【The invention's effect】
As described in detail above, the present invention provides a method for forming a main pipe by bending a flat strip and forming a through hole in the strip and inserting the end of the branch pipe into the through hole. Since the outer periphery of the end of the branch pipe projecting to the back side of the pipe and the peripheral edge of the through hole are welded, the header can be easily formed, and the projection angle, size, etc. of each branch pipe can be made accurate. .
Therefore, when this header is used for a hermetic cooling tower, connection with a conduit can be easily performed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a process of making a through hole in a band plate showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a process of fitting an end portion of a branch pipe into a through hole and welding.
FIG. 3 is a cross-sectional view of a header obtained by the present invention.
FIG. 4 is a half sectional view of a hermetic cooling tower.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tower body 2 Upper tank 3 Filler unit 4 Conduit 5 Main pipe 6 Branch pipe 5a Flat strip A Header

Claims (1)

A manufacturing method of a header, comprising: forming a main pipe by bending a flat strip, and manufacturing a header having a plurality of branch pipes projecting from the main pipe.
(1) Drilling a plurality of through holes at predetermined intervals along the longitudinal direction of the strip,
(2) The end of the branch pipe prepared in advance is fitted into each through hole from one side of the strip, and the outer periphery of the end of each branch projecting to the back side of the strip and the peripheral edge of the through hole And welding,
(3) Bending the longitudinal side edge of the strip to which the branch pipe is connected to the back side of the strip, and butt welding the side edges of the strip to form the main pipe,

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