JPH0231601B2 - TSUGIMENASHIKANNOKEISHAATSUENHOHOOYOBISOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for inclined rolling of seamless pipes.

[Prior Art] Generally, in a pipe manufacturing line for seamless pipes such as seamless steel pipes, the rolling process begins by perforating a round billet extracted from a heating furnace using an inclined rolling mill called a piercer.

After the round billet is pierced and rolled by a piercer, various rolling mills are used depending on the various pipe manufacturing methods.

For example, in the case of the Mannesmann plug mill method, a tilt rolling mill called an elongator similar to a piercer, a plug mill, a reeler, a sizer, etc. are used, and for example, in the case of the mandrel mill method, a mandrel mill, A rolling mill such as a stretch reducer is used.

The present invention provides a piercer in the pipe manufacturing line,
This relates to inclined rolling using elongators, reelers, etc.

FIGS. 5 to 7 are explanatory diagrams showing a conventional inclined rolling mill for the purpose of perforation. As shown in FIGS. 5 to 7, each of the upper and lower rolling rolls _{1 and 2} has a barrel-shaped or It has a cone shape, and the axes of the rolling rolls 1 and 2 are tilted in opposite directions with respect to the vertical plane of the pass line PL through which the round billet or blank pipe 3 passes, as shown in Fig. 5. The slope is set with β.

As shown in FIG. 7, guide shoes 4 and 5 are disposed on the left and right between the upper and lower rolling rolls 1 and 2, sandwiching the pass line PL.

For barrel-shaped rolls, the maximum diameter part of each rolling roll 1 and 2 is called the gorge part, and for cone-shaped rolls, the position of the inflection point of the roll diameter is called the gorge part; The tip of the rolling plug 7, supported at the rear by the plug bar 6, is placed a predetermined distance away from the position where the rolls face each other and the distance between the rolls is the minimum, toward the inlet of the rolling mill. Positioned.

Both ends of the shafts 1A and 2A of each rolling roll 1 and 2 are
Although supported by bearings provided inside the rolling mill main body, one end of each roll shaft 1A, 2A is connected to the respective driving electric motor 10A, 10B via a spindle 8, 9, respectively. The rolling rolls 1 and 2 are rotated in the same direction by the driving electric motors 10A and 10B.

[Problems to be Solved by the Invention] By the way, the conventional inclined rolling mill as described above has the following problems.

An inclined rolling mill is a rolling mill that converts the amount of thickness reduction into mainly an extension in the longitudinal direction of the pipe when reducing the thickness of the pipe. However, as can be said conspicuously about plate rolling, the reduction in thickness generally contributes to elongation of the plate in the rolling direction, and only a small amount of expansion in the width direction of the plate perpendicular to the rolling direction. Therefore, in inclined rolling, since the tube is rolled while rotating, the amount of thinning naturally acts in the direction in which the circumference of the tube increases, but this is reduced by the guide shoe 4. , 5 is forcibly converted into elongation in the longitudinal direction of the pipe. Such a rolling process is very unstable, and during rolling, the rolling plug 7 may vibrate or
If the guide shoe is biased toward the 4 or 5 side,
There are many problems such as the occurrence of scratches on the surface of the rolled material 3 due to the large force acting on the rolled material 3 from the guide shoes 4 and 5.

In order to solve these problems, the conventional technology
(1) A method similar to the Atssel mill, in which the rolling rolls 1 and 2 are provided with a stepped shape called a hump to direct the metal flow in the circumferential direction of the tube to the longitudinal direction of the tube; (2) Rolling The rolls 1 and 2 are made into cone-shaped rolls, and the circumferential speed of the rolling rolls is made faster as the rotational circumferential speed of the rolled material 3 increases toward the exit side of the rolling mill. (3) As shown in Japanese Unexamined Patent Publication No. 57-70008, the guide shoes 3 and 4 are replaced with the conventional fixed type guide shoes, and disc-shaped rolls are used to rotate in the longitudinal direction of the pipe. A method has been proposed in which a However, although these conventionally proposed methods have some effects, they do not fundamentally improve the essential defects of the rolling mechanism of an inclined rolling mill.

An object of the present invention is to enable stable manufacture of seamless pipes of good quality.

[Means for Solving the Problems] The method for inclined rolling of seamless pipes according to the present invention involves the following steps:
The rolling rolls are arranged at an angle with respect to the rolling pass line, and a speed difference is given to the rotational speed of each of the rolling rolls, so that tension is applied in the longitudinal direction of the material to be rolled.

Further, the seamless pipe inclined rolling apparatus according to the present invention includes a plurality of rolling rolls arranged concentrically and adjacent to each other around an axis arranged at an angle with respect to a rolling pass line, and providing a speed difference in the rotational speed of the rolling rolls. The rolling mill has a driving means for driving these rolling rolls, so that tension can be applied in the longitudinal direction of the material to be rolled.

[Function] According to the method and apparatus for inclined rolling of a seamless pipe according to the present invention, it is possible to reliably apply a large tension in the longitudinal direction of the pipe, and it is possible to stably manufacture a high-quality seamless pipe. It becomes possible.

[Example] Figure 1 is a plan view showing an example of the present invention, and Figure 2 is a plan view showing an example of the present invention.
The figure is a cutaway view showing the main part along the - line in Fig. 1, Fig. 3 is a cutaway view showing the main part along the - line in Fig. 1, and Fig. 4 is a cutaway view showing the main part along the - line in Fig. 1. FIG. 2 is a cross-sectional view schematically showing a main part along the - line in the figure.

Each of the upper and lower rolling roll groups 11 and 12 has an inclination angle β in opposite directions with respect to the vertical plane of the pass line PL through which the round billet or raw pipe 13 passes.
The slope is set with . Between the upper and lower rolling roll groups 11 and 12, guide shoes are arranged on the left and right sides with the pass line PL in between. Further, in the rolling area of both rolling roll groups 11 and 12, a rolling plug 1 whose rear end is supported by a plug bar 14 is provided.
The tip of No. 5 is positioned.

The upper rolling roll group 11 is constructed by arranging a main roll 16 and a tension roll 17 concentrically and adjacent to each other. In addition, lower rolling roll group 1
2 is constructed by arranging a main roll 18 and a tension roll 19 concentrically and adjacent to each other. The main rolls 16, 18 and the tension rolls 17, 19 are barrel-shaped rolls, but they may also be cone-shaped rolls or parallel rolls.

The main rolls 16 and 18 are supported by roll bearings 20 of the rolling mill main body, and can be driven in the same direction by main electric motors 23 and 24, respectively, via spindles 21 and 22.

Each tension roll 17, 19 is sleeve-shaped and is fitted into a shaft 25 which is coaxially integrated with the corresponding main roll 16, 18 via bearings 26, 27, and is fitted into a shaft 25 of the main roll of the rolling mill. It is supported by a bearing part 28. Each rolling roll group 1
1 and 12, by making the rotational speed of the tension rolls 17 and 19 higher than the rotational speed of the main rolls 16 and 18, the round billet or blank pipe 13 as the material to be rolled is rolled as shown in FIG. It is possible to apply tension F and rotational force in the tube axis direction. From the rolled material 13 to the main rolls 16, 18
The rolling load applied to the tension rolls 17 and 19 is supported by the rolling mill housing via roll bearings 20 and 28.

The shafts 25 of the main rolls 16, 18 and the shafts 30 of the tension rolls 17, 19 are inserted into a gear box 31 having a planetary gear mechanism. Inside the gearbox 31, there is a main roll 1.
A gear 32 connected to the shaft 25 of the tension rolls 17 and 18, a gear 33 connected to the shaft 30 of the tension rolls 17 and 19, a planetary gear 34 that meshes with the gears 32 and 33, and a planetary gear 34 that supports the planetary gear 34. A connecting rod 35 that causes the planetary gear 34 to revolve around the gear 32 is built-in. 36 is an electric motor, connecting rod 3
5, and enables the connecting rod 35 to be driven. That is, the main motors 23, 2
4 and the electric motor 36 constitute the driving means of the present invention, and when the main rolls 16 and 18 are driven by the main electric motors 23 and 24, the planetary gear 34 around the gear 32
By adjusting the revolution speed of the shaft 25 and the shaft 30 using the electric motor 36, it is possible to give a difference in the rotational angular speed of the shaft 25 and the shaft 30.

A gear or the like may be interposed between the electric motor 36 and the rotation center shaft 37 of the connecting rod 35 for torque adjustment.

According to the embodiment described above, it is possible to reliably apply a large tension in the longitudinal direction of the rolled material 13, and it is possible to stably obtain a seamless steel pipe of good quality without uneven thickness, flaws, etc. It becomes possible.

Note that the drive means in the present invention may be of any type as long as it can provide a speed difference between the main rolls 16, 18 and the tension rolls 17, 19, and is therefore not limited to a system having a planetary gear mechanism. , (1) a system including a variable speed gear device, or (2) a system in which the main roll and the tension roll are each rotationally driven by an independent drive source, etc. may be adopted.

[Effects of the Invention] As described above, the method for inclined rolling of a seamless pipe according to the present invention involves arranging a plurality of rolling rolls concentrically and adjacently, and arranging the rolling rolls at an angle with respect to the rolling pass line. , and a speed difference is given to the rotational speed of each of the above-mentioned rolling rolls, so that tension is applied in the longitudinal direction of the material to be rolled.

Further, the seamless pipe inclined rolling apparatus according to the present invention includes a plurality of rolling rolls arranged concentrically and adjacent to each other around an axis arranged at an angle with respect to a rolling pass line, and providing a speed difference in the rotational speed of the rolling rolls. The rolling mill has a driving means for driving these rolling rolls, so that tension can be applied in the longitudinal direction of the material to be rolled.

Therefore, according to the present invention, it is possible to reliably apply a large tension in the longitudinal direction of the pipe, and it is possible to stably manufacture a seamless pipe of good quality.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one embodiment of the present invention, and FIG.
The figure is a cutaway view showing the main part along the - line in Fig. 1, Fig. 3 is a cutaway view showing the main part along the - line in Fig. 1, and Fig. 4 is a cutaway view showing the main part along the - line in Fig. 1. 5 is a plan view showing a conventional example; FIG. 6 is a cross-sectional view schematically showing the main part along the - line in FIG. 5; FIG. 7 is a sectional view taken along the - line in FIG. 5. 13... Rolled material, 16, 18... Main roll, 1
7, 19... Tension roll, 23, 24... Main motor, 36... Electric motor.

Claims (1)

[Scope of Claims] 1. In a state in which a plurality of rolling rolls are arranged concentrically and adjacent to each other, the rolling rolls are arranged at an angle with respect to the rolling pass line, and a speed difference is given to the rotational speed of each of the rolling rolls, and An inclined rolling method for seamless pipes that applies tension in the longitudinal direction of the rolled material. 2. It has a plurality of rolling rolls that are arranged concentrically and adjacent to each other around an axis that is inclined with respect to the rolling pass line, and a driving means that drives the rolling rolls so as to give a speed difference to the rotational speed of the rolling rolls. This is a seamless pipe inclined rolling device that can apply tension in the longitudinal direction of the material to be rolled.