JPH0357339Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Field of industrial application] The invention involves bending a metal plate sequentially using multiple pairs of forming rolls, and then welding both ends of the metal plate at the final forming part by electric resistance welding. A pair of squeeze side rolls supports both sides of the heated electric resistance welded tube immediately after electric resistance welding, and a pair of squeeze head rolls disposed above the pair of squeeze side rolls This invention relates to a cooling device for a squeeze head roll in a pipe-making machine for forming an ERW pipe by joining and press-forming ERW parts.

[Conventional technology]

The squeeze head roll is disposed in an inverted V-shape above a pair of squeeze side rolls in the final forming part of a large number of pairs of forming rolls for sequentially bending and forming a metal plate into a tubular shape. This squeeze head roll pressure-forms the ERW part of the ERW pipe (this part is heated) immediately after electric resistance welding, so the heat of the ERW part of the ERW tube is conducted, and as a result, it heats up to a high temperature. be done. When the squeeze head roll is heated to a high temperature, it will become tempered, which will induce severe wear and surface cracking, and its service life will be significantly reduced.

A conventional squeeze head roll has a structure as shown in FIG. A roll body 24 is rotatably supported on a roll shaft 22 fixed to a yoke 21 via a bearing 23, and a seal 26 is attached to a bearing cover 25 to prevent oil from dripping from the bearing 23. This is a structure that prevents this.

In order to cool the squeeze head roll with such a configuration, water is poured directly onto the roll body 24, which may cause the roll body 24 to cool down rapidly and cause cracks, or the water poured onto the roll body 24 may cause damage to the ERW. It dripped down to the electric resistance welding part 27 of the pipe P, and that part was annealed, resulting in a decrease in quality.

Further, the conventional squeeze head roll described above has two parts that rotatably support the roll body 24.
Since the bearings 23 are close to each other, the roll shaft 22
The attachment of the roll body 24 to the bearing 23 and the roll body 24 became unstable, and as a result, an unreasonable load was applied to both the bearing 23 and the roll body 24, shortening their life spans, and also causing the roll body 24 to bend.

The squeeze head roll described above has a fixed roll shaft, but the roll shaft and roll body are integrated and the roll shaft is rotated, and cooling water holes are formed inside the roll shaft and roll body. There is also a type that cools the roll body with water.

This roll shaft rotating type has bearings installed on the outside of the roll body (both ends of the roll shaft), so it is necessary to maintain watertightness when providing cooling water holes inside the roll shaft and roll body. Although it has the advantage of not requiring the use of any sealing material, it is necessary to support both ends of the roll shaft with bearings, so the narrow overflow sandwiched between a pair of squeeze head rolls must be supported. Two bearings must be installed in a certain area (the area indicated by E in FIG. 6).

As a result, the forming load supporting capacity of the bearing in this area becomes smaller, and the oil, etc. in the bearing in this area drips down to the ERW part of the ERW pipe, causing the same problem as the above-mentioned annealing of the ERW part. It was hot.

In addition, as a water cooling device for squeeze side rolls in forming electric resistance welded pipes, the one described in Utility Model Publication No. 19033/1983 was known before the filing of this application.
This water cooling device has a structure in which a squeeze ring (a portion corresponding to the roll body in the present invention) is provided with an annular water cooling jacket, and cooling water is circulated through the water cooling jacket. In this device, since the squeeze ring rotates (co-rotates) together with the rotating shaft, there is no need to provide a cooling water communication section between the rotating part and the non-rotating part.
It is extremely easy to provide a cooling water hole in the rotating shaft for supplying cooling water to the water cooling jacket of the squeeze ring.

[Problem that the invention attempts to solve]

The present invention makes it possible to cool the roll body with a high cooling effect in a type of squeeze head roll with a fixed roll shaft, and at the same time increases the load supporting capacity originally required for the squeeze head roll. It was done for that purpose.

[Means for solving problems]

In this invention, among many pairs of forming rolls for sequentially bending a metal plate and forming it into a tube shape, the final forming part is arranged in an inverted V-shape above a pair of squeeze head rolls in the final forming part. In a cooling device for squeeze head rolls in a pipe making machine for water cooling a pair of squeeze head rolls for pressure forming an electric resistance welded part of A shaft is non-rotatably fixed to a yoke provided above the squeeze side roll, and the roll body is rotated on the roll shaft via a pair of bearings disposed at both ends of the roll body in the direction of the rotation axis. The opening on the pressure side of the roll body is kept watertight and closed with a lid to form an annular water reservoir hole inside the pressure side of the roll body, and the above-mentioned pair of bearings Two annular communication portions are provided between the outer circumferential surface of the roll shaft and the inner circumferential surface of the roll body in a water-tight manner, respectively, and the inflow cooling water holes provided in the roll shaft and the roll body are connected to each other, and The outflow cooling water holes are made to communicate with each other via the annular communication portion, and each of the inflow and outflow cooling water holes provided in the roll body is made to communicate with the annular water reservoir hole, respectively. .

[Effect of invention]

The cooling water supplied to the inflow cooling water hole of the fixed roll shaft is guided to the inflow cooling water hole of the roll body through an annular communication section provided between the roll shaft and the roll body, and It enters the annular water hole provided in this. The roll body is heated by conduction of heat from the ERW section of the ERW pipe through the pressurizing surface, but because the annular water reservoir hole is provided inside the pressurizing surface of the roll body, the roll body is heated effectively. is water cooled. The cooling water, whose temperature has increased due to heat conduction, exits from the annular water reservoir hole in the roll body, flows out to the outflow cooling water hole in the roll body, and flows through the annular communication provided between the roll shaft and the roll body. The water flows out through the cooling water hole of the roll shaft and is discharged.

In addition, since the roll body is rotatably supported on the roll shaft via a pair of bearings arranged at both ends of the roll body in the direction of the rotation axis, the forming load of the ERW tube is not forced through the bearings. without being transmitted to the roll axis. This prevents the roll body from deflecting due to excessive forming loads, and since the roll shaft is fixed and the bearings are internally housed in the roll body, the forming load supporting capacity of the bearings is increased, and the bearing's oil etc. will not drip into the ERW pipe.

〔Example〕

A pair of squeeze head rolls, which are the object of the present invention, are arranged in an inverted V-shape above the squeeze side roll in the final forming section among the many pairs of forming rolls for sequentially bending a metal plate and forming it into a tubular shape. It will be arranged as follows.

A roll shaft A fixed to a yoke 1 via a key 2 has an inflow cooling water hole 3a and an outflow cooling water hole 4a arranged in a distributed manner with respect to the rotation axis C of the roll body B. They are provided in parallel (see Fig. 3), and at the tips of each of the cooling water holes 3a and 4a, there is an inflow cooling water hole 3 that communicates with the outer circumferential surface of the roll shaft A.
b and the outflow cooling water hole 4b are connected.

The inflow cooling water hole 3b and the outflow cooling water hole 4
Annular grooves 5 and 6 are provided in the portions where b opens to the outer periphery of the roll shaft A, respectively.

The roll body B is rotatably supported on the roll axis A by a pair of bearings 7 disposed at both ends of the roll body B in the direction of the rotation axis C, and each of the annular grooves 5,
6 is provided between a pair of bearings 7. Three watertight seals 8 are provided in the portion of the roll shaft A where the annular grooves 5 and 6 are provided, thereby ensuring watertightness with the outside and watertightness between the inflow and outflow cooling water holes. is retained.

Each roll body B has cooling water holes 3 for inflow.
c and outflow cooling water holes 4c are provided in the radial direction, and each cooling water hole 3c, 4c is connected to the roll axis A.
The annular grooves 5 and 6 are in communication with each other.

Inflow cooling water hole 3c provided in roll body B
An inflow cooling water hole 3d and an outflow cooling water hole 4d, which are provided parallel to the rotational axis C, are connected to the outflow cooling water hole 4c.

The opening on the side where the pressure surface 9 of the roll body B is provided is closed by fitting the lid D, thereby forming an annular cooling water reservoir hole 10 inside the pressure surface 9 of the roll body B. Ru. The lid D is fitted into the roll body B via rings 11, 12, and 13, thereby maintaining watertightness.

The inflow cooling water holes 3e and the outflow cooling water holes 4e provided in the radial direction of the lid body D are connected to the inflow cooling water holes 3d and the outflow cooling water holes 4d provided in the roll body B, respectively. and communicates with the cooling water reservoir hole 10.

As a result, as shown by the arrow in Figure 2,
The cooling water that has flowed into the cooling water reservoir hole 10 through the inflow cooling water holes 3a, 3b, 3c, 3d, and 3e flows out to the outside through the outflow cooling water holes 4e, 4d, 4c, 4b, and 4a. .

In the above embodiment, the annular grooves 5 and 6 provided on the outer periphery of the roll shaft A constitute an annular communication portion of the cooling water hole.

In addition, in Fig. 2, 14 is a bearing cover, and 15 is a bearing cover.
indicates a seal that prevents oil, etc. from the bearing 7 from leaking to the outside.

Then, when the ERW pipe P whose ERW part 16 was electrically resistance welded in the previous process moves in its axial direction, the pair of roll bodies B pressing the ERW part 16 of the ERW pipe P from diagonally above move around the rotation axis. The electric resistance welded portion 16 of the electric resistance welded tube P is pressurized by the roll body B and deformed by driven rotation about the center C.

As a result, the roll body B is heated, but the cooling water that has flowed into the cooling water reservoir hole 10 through the inflow cooling water holes 3a, 3b, 3c, 3d, and 3e is transferred to the outflow cooling water holes 4e, 4d, and 4c. , 4b, 4a to the outside, the part of the pressurizing surface 9 that is heated the most is effectively cooled by the cooling water stored in the cooling water reservoir hole 10, and the roll body B The roll body B is cooled by cooling water passing through the inflow and outflow cooling water holes provided inside the roll body
The entire area is cooled.

In FIG. 1, reference numeral 17 indicates squeeze side rolls, and by applying a pair of squeeze side rolls 17 to both sides of the electric resistance welding tube P and press-forming the electric resistance welding portion 16 of the electric resistance welding tube P with the roll body B, The welding butt conditions are completed by preventing deformation of the electric resistance welded pipe P.

In addition, bearings 7 are provided at both ends of the roll body B in the direction of the rotation axis C, and the bearings 7 rotatably support the roll body B on the roll axis A. The structure is such that the forming load is naturally applied to the pair of bearings 7.

Therefore, there is no fear that the roll main body B will be bent due to excessive forming load, and the forming accuracy of the electric resistance welded portion 16 of the electric resistance welded tube P is improved.

In addition, since the roll shaft A is fixed and the pair of bearings 7 are installed inside the roll body B, the forming load supporting capacity of the bearings 7 is increased, and oil etc. from the bearings 7 is prevented from dripping into the ERW pipe P. Nor.

[Effect of idea]

The present invention provides a squeeze head roll in which a roll body is rotatably supported on a roll shaft fixed to a yoke via a pair of bearings, and the present invention provides a squeeze head roll having a structure in which a roll shaft is fixed to a yoke, and a roll body is rotatably supported through a pair of bearings. Two annular communication parts are provided between the peripheral surface and the
Since the structure is such that cooling water is supplied to the annular cooling water reservoir hole provided inside the pressurizing surface of the roll body, the pressurizing surface of the squeeze head roll, which is most easily heated, can be cooled with water with a high cooling effect. At the same time, the forming load supporting force of the bearing can be increased, and the forming accuracy of the electric resistance welded portion of the electric resistance welded tube is improved.

Furthermore, since the distance between the pair of bearings built into the roll body is large, the resistance welded tube forming load is easily applied to the bearings, so that no unreasonable forming load is applied to the roll body. As a result, there is almost no deflection of the roll body, improving the precision of forming the electric resistance welded portion of the electric resistance welded tube, and since the bearing is housed inside the roll body, oil and the like will not drip into the electric resistance welded tube.

[Brief explanation of the drawing]

FIG. 1 shows an electric resistance welding section 1 of an electric resistance welded pipe P using a squeeze head roll equipped with a water cooling device according to the present invention.
2 is a longitudinal sectional view of the squeeze head roll, FIG. 3 is a side view of the roll shaft A, and FIG. 4 is a cross section taken along line X-X in FIG. 2. 5 is a sectional view taken along the Y--Y line in FIG. 2, and FIG. 6 is a longitudinal sectional view of one of a pair of conventional squeeze head rolls. The explanation of the symbols of the main parts is as follows. A
...Roll axis, B...Roll body, C...Rotation axis of roll body, D...Lid body, P...Erw tube, 1
... Yoke, 3a to 3e ... Inflow cooling water hole, 4
a to 4e... Outflow cooling water hole, 5, 6... Annular groove (annular communication part), 7... Bearing, 10... Cooling water reservoir hole, 16... ERW part of the ERW pipe.

Claims (1)

[Scope of Claim for Utility Model Registration] Among the many pairs of forming rolls for sequentially bending a metal plate and forming it into a tube shape, a pair of squeeze side rolls arranged in the final forming section are arranged in an inverted V-shape above a pair of squeeze side rolls arranged in the final forming section. A cooling device for squeeze head rolls in a pipe making machine for water-cooling a pair of squeeze head rolls for pressure-forming the electric resistance welded portion of an electric resistance welded pipe. A roll shaft, each provided with a cooling water hole, is non-rotatably fixed to a yoke provided above the squeeze side roll, and a pair of roll shafts provided at both ends of the roll body in the direction of the rotation axis are connected via bearings. The roll body is rotatably supported on the roll shaft, and the openings on both sides of the roll body are kept watertight and closed with lids, thereby forming an annular water reservoir hole inside the pressure surface of the roll body. two annular communicating portions are provided between the above-mentioned pair of bearings between the outer circumferential surface of the roll shaft and the inner circumferential surface of the roll body in a watertight manner; The inflow cooling water holes and the outflow cooling water holes are communicated with each other through the annular communication portion, and each of the inflow and outflow cooling water holes provided in the roll body is connected to the annular water reservoir hole. A cooling device for squeeze head rolls in a pipe making machine, characterized in that they are connected to each other.