JPH038506A - Control method for rolling by reeler roll - Google Patents

Abstract

PURPOSE:To improve bite and also to enable the high work efficiency of the control of rolling by reeler rolls by performing reeling by making the inclined angle of reeler rolls smaller when a tube is bitten and making the above inclined angle larger after biting. CONSTITUTION:Each of the reeler rolls 21, 22 is respectively inclined just at a specified angle in the opposite direction to a horizontal plane with a control device for inclined angle and is revolved in the same direction with a driving gear. When a tube 1 to be done reeling is bitten, reeling is performed by moving a reeler plug 3 while the plug is inserted in the direction of the pass line of the tube 1. Because the inclined angle of the reeler rolls is decreased when the tube is bitten, the fraction defective of bite is decreased. And because the above-mentioned inclined angle is increased after the tube is bitten, the advancing speed of the tube becomes faster and the efficiency of work is improved. Thereby, the goodness of bite and the high efficiency of work are compatible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rolling control method in a gluer for polishing the inner and outer surfaces of a seamless pipe.

[Conventional technology]

To manufacture seamless steel pipes using the Mannesmann plug mill method, a piercer is used to perforate the axial center of a heated billet, the wall is made thinner and the diameter is expanded using an elongator, and after elongation and rolling is performed using a plug mill, the inner and outer surfaces of the pipe are cut using a reeler. This is done by reeling and finishing with sipes to the specified dimensions.

In the reeling step, the tube is expanded in diameter and simultaneously rolled to thicken the tube using a reeler consisting of a reeler roll and a reeler plug. - Reeling for boat fishing involves disposing a reeler plug between a plurality of cylindrical reeler rolls, inserting a tube into the reeler roll, and moving the tube in its length direction while removing the plug. This is done by inlaying. When carrying out such a ring, it is necessary to rotate the two reeler rolls in the same direction at the same speed, and to provide an inclination angle by tilting the roll axes in opposite directions at a predetermined angle with respect to the horizontal direction. This tilting of the roll axis is necessary to provide propulsion to the tube. It is known that as the inclination angle increases, the efficiency (forward speed) in reeling increases.

[Problem to be solved by the invention]

However, in reeling, when the pipe is bitten by the reeler roll, if the angle of inclination is large, many injection defects occur. Figure 4 is a graph showing the relationship between the inclination angle and the injection defect rate and efficiency (advance speed) of the bow roll, with the inclination angle on the horizontal axis and the injection defect rate and efficiency (advance speed) on the vertical axis. The relationship between the two is shown by white circles for injection defect rate and black circles for efficiency (forward speed).

In addition, in the figure, the injection defect rate and efficiency are determined when the inclination angle is 6.
In the case of deg, each value is assumed to be 100, and the magnitude is expressed relative to this value. As is clear from the figure, as the inclination angle increases, the forward speed of the tube increases and efficiency improves.
As a result, the injection defect rate increases rapidly.

In reeling, since the biting property is prioritized and emphasized, the relationship between the injection failure rate and the inclination angle as described above is taken into account, and the inclination angle is limited to reduce the injection failure rate. Since the angle of inclination cannot be increased, the forward speed of the tube after biting is slow, resulting in low work efficiency.

The present invention has been made in response to such circumstances, and it is possible to reduce the inclination angle of the reel roll when biting into the tube, and increase the inclination angle of the reeler roll after the biting, thereby reeling. It is an object of the present invention to provide a rolling control method for a reeler roll that has good properties and high work efficiency.

[Means to solve the problem]

The rolling control method for a reeler roll according to the present invention reduces the inclination angle of the reeling roll when biting into a pipe to be rolled,
It is characterized in that the angle of inclination is increased after biting.

[Effect]

When the tube is bitten by the reeler roll, the inclination angle of the reeling roll is made small to slow down the forward speed of the tube, thereby suppressing defective injection of the tube into the reeler roll.

After biting, the inclination angle of the reeler roll is increased to increase the forward speed of the tube and improve reeling efficiency.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof.

FIG. 1 is a schematic partially cutaway plan view showing an apparatus for carrying out the rolling control method for a reeler roll according to the present invention;
The figure is a schematic front view thereof. In the figure, 21.22
These Leela Rolls 21.2
A beam-love rug 3 is placed between the two. The reeler rolls 2122 are each tilted by an inclination angle θ in opposite directions with respect to a horizontal plane by an inclination angle control device (not shown), and rotated in the same direction by a reeler roll drive device (not shown). When the tube 1 to be reeled is bitten by the reeler roll 2L 22, the tube 1 moves in the direction of the white arrow shown in FIG. and is reeled.

Next, using the device as described above, the reeler rolls 21° and 22
A method for controlling the inclination angle will be explained.

FIG. 3 is a graph showing the process of tilt angle control, with elapsed time plotted on the horizontal axis and tilt angle plotted on the vertical axis to show the relationship between the two. In the figure, a indicates the rolling start point, and indicates the point in time when the tip of the tube 1 is bitten into the reeler rolls 21 and 22. bl is the steady rolling start point, which is 50 to 10 mm from the tip of the pipe 1.
It indicates the point in time when a length of 0 m1 (depending on the pipe size) has passed.

Further, the time point at which steady rolling starts is also the starting point for changing the inclination angle of the reeler rolls 21 and 22, and this inclination angle change ends at the end point b2 for changing the inclination angle. The rolling ends at the rolling end point indicated by C. When setting the inclination angle, the rolling start point a is set to, for example, 6 degrees, which gives a small injection defect rate, taking into consideration the biting property.

Since there is no need to consider the biting property at the steady rolling start point b1, the inclination angle control device sets the inclination angle to, for example, 10 degrees in order to increase the forward speed of the tube 1 and improve work efficiency. starts changing the inclination angle. Then, the change in the inclination angle is finished at the inclination angle change end point b2, and thereafter, reeling is performed at the changed inclination angle until the rolling end point C is reached.

〔Effect of the invention〕

As described in detail above (in the reeler roll rolling control method according to the present invention, the inclination angle of the roll is made small when the tube is biting in, so the injection defect rate is reduced, and after the tube is biting in, the rolling control method of the reeler roll is small). First, since the angle of inclination of the rolls is increased, the forward speed of the tube becomes faster, which improves work efficiency.In this way, it is possible to achieve both good biting performance and high work efficiency. has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a schematic partially cutaway plan view showing an apparatus for carrying out the method of the present invention, Fig. 2 is a schematic front view thereof, Fig. 3 is a graph showing the process of controlling the inclination angle, and Fig. 4 is a graph showing the relationship between the inclination angle of the reeler roll, the injection failure rate, and the efficiency (advance speed).

Claims (1)

[Claims] 1. A method for controlling the rolling of a reeler roll, characterized in that the angle of inclination of the reeler roll is made small when biting into a tube to be rolled, and the angle of inclination is made large after biting.