JPS5950428B2 - Tension adjustment device for material at welded parts in pipe manufacturing process - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention applies appropriate tension to the material at the welding part of the pipe manufacturing process, in which a strip-shaped material is formed into a tube shape and both sides of the material are seam-welded to form a predetermined size and shape. The present invention provides a tension adjustment device that can perform stable and good welding, especially when welding extremely thin-walled and small-diameter pipes by high-frequency induction heating welding.

In Fig. 1, which shows an outline of the pipe making process, 1 is a raw material coil in which a strip-shaped material is wound into a coil shape, and 2 is a raw material coil 1.
3 is the raw material coil 1
5 is a forming zone that gradually forms the strip-shaped material 4 into a tubular shape, 6 and 7 are vertical and horizontal forming rolls, respectively, and 8 is the material 4 formed into a tubular shape. 9 is an edge heating device such as a high-frequency induction heating device, and 10 is a squeeze device that presses both edges of the heated material against each other as shown in Fig. 2. It's a roll.

11 is a cooling device; 12 is a bead cutting machine that cuts off the weld bead on the outer circumferential surface of the tube to create a smooth circumferential surface; and 13 is a sizing device that shapes the outer diameter, inner diameter, shape, etc. of the tube to a predetermined size and shape. In the zone, 14 and 15 are vertical and horizontal sizing rolls, respectively, and 16 is a running cutting machine for cutting the pipe into a predetermined length.

In such a pipe-making process, especially when welding extremely thin-walled, small-diameter pipes using high-frequency induction heating, wrinkles occur in the heated portion of the material, and if these wrinkles are welded as they are, the weld bead will not be finished neatly. Therefore, the running speed of the pipe in sizing zone 13 is set to
The running speed of the material was increased to apply appropriate tension to the material in order to remove wrinkles. However, as shown in FIG. te1
In the case of a so-called one-shaft drive or drive connected in conjunction with the main drive shaft 23, the gear ratio is constant, so the tension can be reduced by appropriately making the roll diameter of the sizing zone 13 larger than the roll diameter of the forming zone 5. It was occurring. Therefore, l) The relationship between the roll diameter and the running speed of the material or pipe and the roll surface, i.e. which part of the contact area between the material or pipe and the roll surface slips and which part is driven, is not technically clarified. Since the so-called drive diameter of the pipe is unknown, we have to rely on intuition and experience, and it is difficult to apply appropriate tension.

2) Because the tension is not appropriate, the speed of the material fluctuates, which adversely affects welding, and may even increase wrinkles, making it impossible to weld.

3) When the pipe diameter or wall thickness changes, change the sizing zone,
The forming zone roll set must be replaced and readjusted, which is time-consuming.

There were other problems.

The device for adjusting the tension of a material in a welded portion according to the present invention was invented to solve the above-mentioned problems of the prior art.
The material tension adjustment device in the welding zone of the present invention interlocks each sizing roll in the sizing zone and interlocks each forming roll in the forming zone with a drive shaft in the sizing zone, one end of which is interlocked and connected to a drive motor. A continuously variable transmission and a clutch are interposed between the connected drive shaft of the forming zone, and the continuously variable transmission controls the ratio of the rotation speed of the forming zone roll to that of the sizing zone roll. The tension of the material can be adjusted by changing the

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 4 showing one embodiment of the present invention, 24 is a drive shaft of the sizing zone 13, 25 is a triple speed reducer, 26 is a universal joint, 27 is a roll stand for the sizing roll 14, and the roll of each roll stand 27 is 14 is operatively connected to a drive shaft 24 via a triple speed reducer 25 and a universal joint 26, and one end (the right end in the figure) of the drive shaft 24 is operatively connected to a drive motor (not shown). 28 is a drive shaft of the forming zone 5, 29 is a triple reducer, 30 is a universal joint, 31 is a roll stand of the forming roll 6, and the roll 6 of each roll stand 31 is a triple reducer 29, a universal joint 30. It is interlocked and connected to the drive shaft 28 via.

32 is a continuously variable transmission; 33 is a powder clutch; the drive shaft 24 of the sizing zone 13 and the drive shaft 28 of the forming zone 5 are interlocked and connected via the continuously variable transmission 32 and the powder clutch 33; Driving force is transmitted from the drive shaft 24 to the drive shaft 28 of the forming zone 5.

In this embodiment, the triple reducer 25 in the sizing zone 13 has a reduction ratio of 1/4.712, and the triple reducer 29 in the forming zone 5 has a reduction ratio of 1/3.1.
25 is used, and the continuously variable transmission 32 has a gear ratio in the range of 1/8.4 to 1/1.4,
The rotation speed of the roll in the forming zone 5 is set to 0.18 to 1.08 with respect to the rotation speed of the roll in the sizing zone 13.
However, it is not necessarily limited to this, and the triple reducers 25, 29 and continuously variable transmission 32 can be appropriately selected according to the conditions of the process. can. Also, although a powder clutch 33 is used in this embodiment, other clutches such as electromagnetic clutches may also be used.

As described above, the material tension adjustment device in a welded part of the present invention has a drive shaft for a sizing zone in which each sizing roll for shaping a pipe into a predetermined size and shape is interlocked and one end thereof is interlocked and connected to a drive motor. A continuously variable transmission and a clutch are interposed between the forming zone drive shaft which interlocks and connects each forming roll that forms a strip material into a tube. When welding by high-frequency induction heating, wrinkles inevitably occur in the heated part of the material because the wall thickness is thin. However, according to the present invention, the continuously variable transmission keeps the rotation speed of the roll in the sizing zone constant and By adjusting the rotational speed ratio of the rolls in the sizing zone, it is possible to apply the optimal tension to suppress the occurrence of wrinkles. This makes it possible to suppress the occurrence of wrinkles much more effectively than in the prior art, which adjusts the tension by changing the ratio.

2) Even when the pipe diameter and wall thickness change, the optimum tension can be set according to the pipe diameter and wall thickness by adjusting the continuously variable transmission.

Therefore, compared to the conventional technology in which the roll sets in the sizing zone and forming zone must be replaced and adjusted, tension adjustment is extremely easy and the number of man-hours can be greatly reduced. 3) For products such as radiator pipes that are deformed from a circle to a flat shape, the forming zone is used to make the product circular for welding.

In the conventional technology, wrinkles could not be suppressed sufficiently, so in order to ensure perfect welding, the circle was made as accurate as possible.However, according to the present invention, wrinkles can be easily removed and welding can be stabilized, so an accurate circle can be created in the forming zone. This eliminates the need for additional processing, which eases processing conditions. 4) Since a clutch is used in addition to the transmission, speed fluctuations due to overload in the forming zone are buffered by the clutch and the influence on the sizing zone is absorbed, so the material pulled by the rolls in the sizing zone is runs at a stable speed, and good welding can be achieved under constant welding conditions.

It has extremely excellent effects such as:

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the outline of the structure of the pipe making process, Fig. 2 is an explanatory diagram of a squeeze roll, Fig. 3 is an explanatory diagram of a conventional roll mechanism with one shaft drive, and Fig. 4 is an explanatory diagram of a conventional roll mechanism according to the present invention. FIG. 2 is an explanatory diagram of one embodiment of a device for adjusting the tension of a material in a welded portion. 5... Forming zone, 6, 7... Forming roll, 8... Welding section, 13... Sizing zone, 14, 15... Sizing roll, 24...
- Sizing zone drive shaft, 28... Forming zone drive shaft, 32... Continuously variable transmission, 33... Powder clutch.

Claims (1)

[Claims] 1 Shape the tube with both sides welded at the welded part into a predetermined size and shape. Each sizing roll is interlockingly connected, and one end of the sizing roll is interlockingly connected to a drive motor. The drive shaft of the sizing zone and the band-shaped material are formed into a tube shape. A device for adjusting the tension of the material at the welding part of the pipe-making process, with a continuously variable transmission and a clutch interposed between the forming zone drive shaft that interlocks and connects each forming roll.