JPS6317028B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for installing a U-shaped tube of a heat exchanger used in refrigeration and air conditioning equipment, etc., and its purpose is to hold a welding material in close contact with the U-shaped tube in advance. To quickly perform installation and connection work of a U-shaped pipe.

An embodiment of the present invention will be described below with reference to FIG. 1. Reference numeral 1 denotes a plate-fin type heat exchanger used in refrigeration and air conditioning equipment, in which a plurality of metal plate-shaped fins 2, 2 are arranged in parallel at equal intervals. and two pieces (only one piece is shown) arranged in parallel with a gap on both sides of the fin.
a plurality of metal straight pipes 4 which are orthogonal to each fin and the tube plate and are fixed to each other to guide the refrigerant;
4, and straight pipe-shaped both end connecting portions 5a at the ends of both straight pipes,
5a, and is fixed to both straight pipes by heating and melting an annular welding material 6, 6 such as a copper port material provided inside the base of both connecting parts as shown in FIG.
Metal U-shaped pipe 5 that connects both straight pipes to each other
It is composed of. The U-shaped tube has expanding tube portions 5b, 5b, which hold the melt material 6, 6, integrally formed at the bases of both connecting portions 5a, 5a so as to protrude outward. The welding material is formed into an annular shape having an inner diameter smaller than the outer diameter of the straight pipes 4, and an outer diameter larger than the outer diameter of the straight pipes 4, 4.

Next, the processing of the U-shaped tube 5 will be explained with reference to FIGS. 3 and 4.

First, a pair of split fixtures 7 (only one is shown) having opposing U-shaped grooves 7a are used to connect the connecting portion 5a,
The U-shaped tube 5 is clamped and fixed, leaving 5a. Next, a small diameter portion 8a having an outer diameter smaller than the inner diameter of the connecting portion.
Then, the pressure plate 9 equipped with the tube expansion tool 8 consisting of a large diameter part 8b having a large outer diameter and an inclined part 8c formed around the small and large diameter parts is lowered, and the connecting part 5 is lowered.
A tube expanding tool 8 is press-fitted into the connecting portions 5a and 5a, and the connecting portions 5a and 5a are expanded using the inclined portions 8c. After the welding material 6, 6 is installed inside the base of the expanded connection parts 5a, 5a, a cylindrical part 10b having an inclined part 10a formed on the inner periphery of the lower end is inserted from the inner periphery of the cylindrical part through a gap 11. The pressurizing plate 12 equipped with the pipe shrinking tool 10 consisting of the columnar part 10c is lowered, and the inclined part 10a is lowered.
Then, leaving the bases of the connecting parts 5a, 5a, the connecting parts 5a, 5a are gradually narrowed and guided into the gap 11 to form expanded pipe parts 5b, 5b that hold the weld metal 6, 6 in close contact with each other.
Finish the tube shrinking process of a.

To explain the installation of the U-shaped tube 5 that has been processed and formed, the weld metal 6, 6 comes into contact with the end surfaces of the straight tubes 4, 4 that are vertically installed, and covers the ends of the straight tubes 4, 4. The connecting parts 5a, 5a are fitted to the ends of the straight pipes 4, 5a from above, and then the U-shaped pipe 5 is heated by a heating means to melt the melting material 6, 6, and the ends of the straight pipes 4, 4 and the U-shaped pipe 5 are heated. By filling the gap between the connecting portions 5a, 5a of the tube 5 from above to below, that is, from the inner end to the outer end of the gap, adjacent straight pipes 4, 4 can be connected to each other via the U-shaped pipe 5. Along with the communication connection, U
The shaped pipe 5 itself is welded to the straight pipes 4, 4.

According to the above mounting method, the annular welding material 6, 6 is attached to the expanded pipe portion 5b formed at the base of the connecting portion 5a, 5a.
5b, the straight pipe 4,
4 and the connecting parts 5a, 5a, the process of installing the welding material 6, 6 inside each time can be omitted,
In addition, it is possible to prevent the welding material 6, 6 from coming off when the U-shaped tube 5 is being transported, and furthermore, the welding material 6, 6 itself acts as a stopper, and the degree of fitting of the U-shaped tube 5 can be made constant.
The installation work of the shaped tube 5 can be carried out quickly, and the area of close contact between the weld metals 6 and 6 is widened by the expanded tube parts 5b and 5b, which improves the heat transfer effect from the heating source to the weld metals 6 and 6. .
Since the upper ends of the straight pipes 4, 4 and the U-shaped pipe 5 are held in close contact with each other as they are melted, the connecting portion 5a,
5a flows from the inner end to the outer end of the gap and is exposed on the surface of the straight pipes 4, 4, so that the entire gap is filled with melted material 6, 6, and this filling is removed from the outside. This allows the connection state between the U-shaped pipe 5 and the straight pipes 5, 5 to be seen at a glance.

As described above, the present invention forms annular expanded pipe portions that hold the welding material in close contact with both ends of a metal U-shaped tube, and allows the U-shaped tube to be formed such that the welding material comes into contact with the vertically erected metal straight pipe and the upper end surface. The ends of the U-shaped tubes are fitted from above, and the melting material is melted by heating means to flow from the inner end to the outer end of the gap between the U-shaped tube and the straight tube to fill the gap, Since it is made by connecting a U-shaped pipe to a straight pipe and connecting adjacent straight pipes in communication, the process of installing welding material in the connection is omitted, preventing the welding material from coming off, and preventing the U-shaped pipe from being overfitted. The U-shaped tube installation work can be carried out quickly by preventing the melting material from forming between the upper end of the straight tube and the connection part of the U-shaped tube as it is melted, since it is held in close contact with the tube expansion section. Since the flow from the inner end of the gap toward the outer end is exposed on the surface of the straight pipe, the entire gap is filled with molten material, and this filling can be confirmed from the outside. You can see the connection status at a glance.

[Brief explanation of the drawing]

The drawings show a method of installing a U-shaped tube for a heat exchanger according to the present invention, and FIG. 1 is a vertical cross-sectional view of the main part of the heat exchanger showing how the U-shaped tube is installed, and FIG. 2 shows the connection between a straight tube and a U-shaped tube. The main part vertical cross-sectional view showing the connected state, and FIGS. 3 and 4 are process diagrams for manufacturing the U-shaped tube. 4... Straight pipe, 5... U-shaped pipe, 5a... Connection part, 5b...
Pipe expansion part, 6...Welding material.

Claims (1)

[Claims] 1. Form an enlarged tube part at both ends of a metal U-shaped tube that holds annular welding material in close contact with it, and insert the ends of the U-shaped tube so that the welding material comes into contact with the upper end surface of the vertically erected straight metal tube. They are fitted from above, and the melting material is melted by a heating means to flow the melting material from the inner end to the outer end of the gap between the U-shaped pipe and the straight pipe, filling the gap.
A method for installing a U-shaped tube for a heat exchanger, in which a U-shaped tube is connected to a straight tube, and adjacent straight tubes are connected for communication.