JPS623718B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a welding method for abutting and welding pipe materials from a direction perpendicular to the circumferential surface of the pipe materials.

Conventionally, when welding by abutting pipe materials from a direction perpendicular to the circumferential surface of the pipe materials, it was necessary to apply curved pressure to the vertical end of the pipe to match the outside diameter of the pipe materials to be welded. The work was extremely tedious.

The present invention was invented in view of the above, and when welding pipe materials against each other from a direction perpendicular to the circumferential surface of the pipe materials, the vertical end surface of the pipe is aligned with the diameter of the pipe to be welded, unlike the conventional method. To provide a welding method that can weld a shape cut at right angles without having to process curved surfaces to fit, and can obtain airtightness.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

1 and 2 show a structure manufactured by the welding method of the present invention, in which a horizontal pipe 1 and a pipe material 3 are welded at right angles.

3 to 9 show a first embodiment of the present invention. First, a cylindrical horizontal pipe to be welded is fixed with a fixed electrode 5 having a recess corresponding to the outer diameter. Next, the pipe material 3 to be welded, with the welding end surface 7 cut at right angles, is held between two semi-cylindrical pressure electrodes 9, and the horizontal pipe 1 and the pipe material 3 are appropriately pressurized. Turn on electricity. Then, the current flowing through the welded surface 1' of the horizontal pipe 1 and the pipe material 3
The joint 11 at the annular tip of the pipe material 3 is heated by the current flowing through the pipe material 3, and is brought into close contact with the horizontal pipe 1.

As described above, in the method of electrically welding the pipe material 3 held by the split electrode 9 toward the horizontal pipe 1 fixed by the fixed electrode 5 while applying pressure, the welding surface 1' of the horizontal pipe 1 is The current density flowing through the pipe material 3 becomes larger than the current density flowing through the pipe material 3, and the joint portion 11 of the annular portion of the pipe material 3 beyond the portion held by the two-part electrode 9 is overheated and melted.
Since there is a risk that the electrode may collapse due to pressure, as shown in FIGS. By providing the curved surface 13, the joint portion 11 of the annular portion melted by the current flowing through the contact portion of the pipe material 3 and the horizontal pipe 1 is gradually crushed by the pressing force of the pressurizing electrode 9, and the horizontal pipe 1 is welded. When the end surface of the pipe material 3 is completely brought into close contact with the surface 1', the concave curved surface 13 of the pressurizing electrode 9 comes into contact with the peripheral surface 12 of the outer periphery of the horizontal pipe 1. Therefore, the current is passed directly between the horizontal pipe 1 and the pressurizing electrode 9, the density of the current flowing through the pipe material 3 is reduced, and heating of the pipe material 3 is suppressed.

10 and 11 show a second embodiment of the present invention, in which the horizontal pipe 1 concave curved surface 1 corresponding to the joint between and pipe material 3
A pressing member 15 made of a material such as copper and having a
is provided, and when pressurizing the pressurizing electrode 9 and energizing it, press the concave curved surface 15' of the pressing member 15 between the tip 9' of the pressurizing electrode 9 and the outer peripheral surface of the horizontal pipe 1 from both left and right sides, The joint 11 of the melted annular portion is gradually crushed by this pressing force, and the end surface of the pipe material 3 is completely brought into close contact with the welded surface 1' of the horizontal pipe 1. At the same time, the concave curved surface 15' of the pressing member 15 is It abuts against the peripheral surface 12 of the outer periphery of the horizontal pipe 1. For this reason, the pressure electrode 9 is
5, the pressure electrode 9 and the horizontal pipe 1 are directly energized via the pressing member 15, and the density of the current flowing through the pipe material 3 decreases, causing heating of the pipe material 3. is suppressed.

Preferably, the configuration of the welding machine used in the welding method of the present invention is a welding machine equipped with a transformer with few leakage magnetic lines of force and a good power factor, and a control device with a good current rise, as in Japanese Patent Publication No. 49-42604. However, this is not necessarily the case.

As described above, according to the welding method of the present invention, in so-called pipe right-angle welding, in which pipe materials are abutted and welded from a direction perpendicular to the circumferential surface of the pipe to be welded, the vertical end face of the pipe is cut at a right angle. Because it can be welded in the same shape and airtight,
The curved surface processing of the end surface of the pipe, which has been conventionally performed, can be omitted, and this can greatly contribute to cost reduction and productivity improvement.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a structure in which the present invention is implemented, FIG. 2 is a front view of the same as above, FIG. 3 is a front view showing each member by the welding method of the present invention, and FIGS. 4 and 5 are A front view and a side view showing right angle welding of pipes welded by the welding method of the invention, FIG. 6 is an explanatory diagram showing the welding method of the invention, and FIG. 7 is a view taken along A-A in FIG. 6.
8 is an explanatory diagram showing a first embodiment of the present invention, FIG. 9 is a perspective view showing a pressurizing electrode of the present invention, and FIG. 10 is an explanatory diagram showing a second embodiment of the present invention. 11 are perspective views showing the pressing member of the present invention. Explanation of the symbols representing the main parts of the drawing, 1...
Pipe to be welded, 1'... Welding surface, 3... Pipe,
5...Fixed electrode, 7...End face of pipe, 9...2
Split pressure electrode, 9'... tip of pressure electrode, 13
... Concave curved surface, 15 ... Pressing member, 15' ... Concave curved surface.

Claims (1)

[Claims] 1. In a method of welding a pipe material 3 perpendicularly against the outer peripheral surface of a cylindrical pipe 1 to be welded, the pipe material 3 has a welding end surface 7 that is substantially perpendicular to the axial direction. The pipe material 3 is held between a pair of pressurizing electrodes 9 so as to substantially surround the outer circumferential surface of the pipe 1 to be welded so that the welding end surface 7 abuts the outer circumferential surface of the pipe 1 to be welded at right angles. The electrode 9 corresponds to the outer peripheral surface of the pipe to be welded 1 on the end face opposite to the pipe to be welded 1 in order to press the peripheral part 12 of the joint part 11 between the pipe to be welded 1 and the pipe material 3 against the pipe to be welded 1. A pressing force is applied to the pressing electrode 9 while applying electricity between the fixed electrode 5 which is provided with a concave curved surface 13 and supports and fixes the pipe to be welded 1 and the pressing electrode 9 which clamps the pipe material 3. By pressing the concave curved surface 13 of the pressure electrode 9 against the peripheral part 12 of the joint part 11 between the pipe to be welded 1 and the pipe material 3 and crushing the molten part generated on the welded end surface 7 of the pipe material 3, the outer periphery of the pipe to be welded 1 is pressed. Welded end surface 7 of pipe material 3 on the surface
A method for welding pipe materials, which is characterized by closely welding. 2. In the method of welding by abutting the pipe material 3 orthogonally against the outer peripheral surface of the cylindrical pipe to be welded 1, the pipe material 3 has a welding end surface 7 substantially perpendicular to the axial direction, and the welding end surface The pipe material 3 is held between a pair of pressurizing electrodes 9 so as to substantially surround the outer peripheral surface of the pipe material 3 so that the electrodes 7 abut perpendicularly to the outer peripheral surface of the pipe material 1 to be welded, thereby supporting and fixing the pipe material 1 to be welded. A pressing force is applied to the pressure electrode 9 while applying electricity between the fixed electrode 5 and the pressure electrode 9 that clamps the pipe material 3, and the surrounding area 12 of the joint 11 between the pipe 1 to be welded and the pipe material 3 is By pressing the joint between the pipe material 3 and the welded member 1 with a pair of pressing members 15 having corresponding concave curved surfaces 15' and crushing the welded portion generated on the welded end surface 7 of the pipe material 3,
A method for welding pipe materials, characterized by closely welding a welding end surface 7 of a pipe material 3 to the outer peripheral surface of a pipe 1 to be welded.