JP2752321B2 - Pipe end automatic welding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube end automatic welding machine for circumferentially welding a large number of tubes and tube sheets at the tube ends.

[0002]

2. Description of the Related Art In order to manufacture a heat exchanger or the like, a bead B is put on a corner of a tube end as shown in FIG. And the tube sheet 1 need to be circumferentially welded.

Conventionally, a pipe end automatic welding machine as shown in FIG. 3 has been used for circumferentially welding a pipe end.

In FIG. 3, reference numeral 1 denotes a tube sheet as a welded portion;
Reference numeral 2 denotes a pipe that is seal-welded to the pipe sheet 1. Reference numeral 6 denotes a welding head casing, 3 denotes a welding torch, and 4 denotes a wire reel that supplies a welding wire 5 to a welding portion. The welding torch 3 is held on the rotating shaft 10 by a welding torch holder 11. 8 is a handle, 7 is a motor,
The rotational force of the motor 7 is transmitted to the rotating shaft 10 by the drive transmitting means 9.
Is transmitted to Reference numeral 12 denotes an adjustment jig for adjusting the position of the welding torch, and reference numeral 13 denotes a ring for locking a hook of a balancer for suspending the welding head 6 at a predetermined height.

In order to circumferentially weld a pipe end using a conventional automatic welding machine, a centering metal fitting (not shown) is attached to the tip of the welding machine, and the centering metal fitting is inserted into the pipe 2 to perform centering. ,
After adjusting the position of the welding torch 3 with the adjusting jig 12, the rotating shaft 10 is rotated while generating an arc from the welding torch 3 to supply the welding wire 5 from the wire reel 4, and the welding of the tube 2 and the tube sheet 1 is performed. The pipe 2 and the pipe sheet 1 are seal-welded by circumferentially welding the stub.

[0006]

However, depending on the manufacturing process of the heat exchanger or the like, after the tube plate and the head plate are first welded,
Many tubes may be welded to the tubesheet. In this way, if the tube plate and the head plate are welded first and the tube end is welded using the above-mentioned conventional tube end automatic welding machine, the work space is narrow, so the wire reel of the conventional automatic welding machine becomes an obstacle. ,
The pipe end could not be automatically welded, and the pipe end had to be welded by seal welding.

[0007] In the conventional pipe end automatic welding machine, since the handle is provided with a motor, the mounting position is fixed, and the handle hits the flange or the end plate of the pipe end. It was difficult to automatically weld the peripheral end of the pipe, and it was necessary to rely on manual welding.

[0008] Therefore, in the conventional automatic pipe end welding machine, the welding of the pipe end in the narrow working space or at the periphery of the tube sheet is very inefficient, and the production cost of the heat exchanger and the like is disadvantageously high. Was.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic pipe end welding machine capable of welding in a narrow working space and also welding a pipe end at a peripheral portion of a tube sheet.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made intensive studies and, as a result, devised a mounting position of a motor for rotating a rotating shaft and a method of supplying a wire reel. As a result, they have found that the above problems can be solved, and have completed the present invention.

That is, the present invention holds a welding torch in a tube-end automatic welding machine that has a welding torch that rotates about the axis of a welding head and that circumferentially welds a tube and a tube plate at the tube ends. A pipe end automatic welding machine, wherein a motor for driving a rotating shaft is provided in a welding head casing such that the rotating shaft of the motor and the axis of the welding head are parallel to each other, and a wire supply device is used as an external supply device. It is about.

[0012]

FIG. 1 is a schematic view showing an embodiment of an automatic pipe end welding machine according to the present invention.

In FIG. 1, reference numeral 1 denotes a tube sheet as a welded portion;
Reference numeral 2 denotes a pipe that is seal-welded to the pipe sheet 1. Reference numeral 6 denotes a welding head casing, and reference numeral 3 denotes a welding torch. The welding torch 3 is held on the rotating shaft 10 by a welding torch holder 11.

A motor 7 for supplying a driving force for rotating the rotating shaft 10 is provided in the welding head casing 6 such that the rotating shaft of the motor 7 is parallel to the rotating shaft 10 of the welding head. The rotational force of the motor 7 is transmitted to the rotating shaft 10 of the welding head by a drive transmitting means provided in the welding head casing, and the welding torch 3 moves circumferentially along the rim of the tube 2.

Since the motor 7 is provided inside the welding head casing 6, the handle 8 can be detached and attached.
Can be provided at an arbitrary position of the welding head casing.

Accordingly, the handle 8 can be replaced at a position where it does not hinder the welding of the tube end of the peripheral portion of the tube sheet, so that the tube end of the peripheral portion of the tube sheet can be easily automatically welded. .

Numeral 12 denotes an adjusting jig for adjusting the position of the welding torch, and numeral 13 denotes a ring for locking a hook of a balancer for suspending the welding head 6 at a predetermined height. Note that the ring 13 can be replaced with a position that does not interfere with the handle 8 as well.

Further, in the present invention, the supply of the welding wire 5 is not performed by the wire reel as in the conventional case, but is performed by the external supply device 14. For this reason, the head of the automatic pipe end welding machine of the present invention can shorten the overall length, thereby enabling automatic pipe end welding in a narrow space. The external wire supply device 14 may be any device that can supply a wire according to the welding speed, and the structure is not particularly limited.

The wire 5 supplied from the external supply device 14 passes through the hollow rotary shaft 10 of the welding head and is supplied to the vicinity of the welding torch 3 by the wire guide 5a.
Welded. By passing the wire 5 through the rotating shaft 10, the wire and the wire guide can be prevented from being twisted.

In order to circumferentially weld a pipe end using the automatic welding machine of the present invention, a centering metal fitting (not shown) is attached to the tip of the welding machine, and the centering metal fitting is inserted into the pipe 2 to perform centering. After adjusting the position of the welding torch 3 with the adjusting jig 12,
The rotating shaft 10 is rotated while generating an arc from the welding torch 3, and while the wire 5 is supplied from the external supply device 14, the tube 2 and the tube sheet 1 are circumferentially welded, and the tube 2 and the tube sheet are welded. 1 may be seal-welded. Depending on the position of the pipe end to be welded, the handle 8 and the ring 13 can be replaced by arbitrary positions and welded. The means for supplying the shielding gas can be arbitrarily provided in the automatic pipe end welding machine of the present invention.

[0021]

According to the pipe end automatic welding machine of the present invention, since the motor for driving the rotating shaft is provided in the casing of the welding head, the handle can be detachably mounted. You can change the mounting position of the handle. Therefore, it is possible to perform automatic welding even at the peripheral end of the tube sheet which has conventionally had to rely on manual welding.

In addition, since the welding wire is supplied externally, the entire length of the welding head can be reduced, so that the pipe end can be automatically welded in a small space.

Further, the automatic pipe end welding machine of the present invention is small in size, has a straight shape when the handle is removed, and can be easily attached to a robot or a manipulator, so that the pipe end welding operation can be completely automated. It becomes possible.

As described above, according to the present invention, the working efficiency of pipe end welding can be greatly improved, and the present invention greatly contributes to the manufacturing industry of heat exchangers and the like.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of an automatic pipe end welding machine according to the present invention.

FIG. 2 is a partial cross-sectional view of a pipe end.

FIG. 3 is a schematic view showing conventional pipe end automatic welding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tube sheet 2 Tube 3 Welding torch 4 Wire reel 5 Welding wire 5a Wire guide 6 Welding head casing 7 Motor 8 Handle 8a Handle attachment part 9 Drive transmission means 10 Rotary shaft 11 Welding torch holder 12 Welding torch position adjusting jig 13 Hook Locking ring 14 Wire external supply device

Claims (1)

(57) [Claims] In a tube end automatic welding machine having a welding torch that rotates around the axis of a welding head and circumferentially welding a tube and a tube sheet at a tube end, a rotating shaft that holds the welding torch is driven. An automatic pipe end welding machine characterized in that a motor to be driven is provided in a welding head casing such that a rotation axis of the motor and an axis of the welding head are parallel to each other, and a wire supply device is an external supply device.