JPS5834205B2 - Method and device for detecting tension and compression forces between stands in a continuous rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for directly detecting tension or compression force (hereinafter referred to as external force) acting on a material between the stands during rolling in a continuous rolling mill consisting of a plurality of stands. and devices.

It is an empirically known fact that when the external force acts on the material between the stands during continuous rolling, damage to production control such as overload operation, misrolling, defective product shape, etc. will occur.

Therefore, conventionally, when the material is flexible, for example in wire rod rolling, when the external force is applied, the magnitude of the external force is directly detected using a so-called looper control method.
A method is used to control the external force so that it is zero or a constant value.

However, although this method is very effective when the material is highly flexible, it has the disadvantage that it cannot be used at all when the material has a large cross-sectional area and therefore has poor flexibility.

Therefore, in the latter case, the magnitude of the external force can be indirectly determined by utilizing the characteristic that the drive motor current, drive torque, or the ratio of rolling torque to rolling load (torque - arm) fluctuates in proportion to the external force. A method is used to detect this and adjust and control the roll rotation speed or roll opening degree accordingly.

However, these methods also have the following drawbacks.

In other words, if skid marks, thermal rundown, or changes in size or shape occur in the material, these will cause disturbances that will significantly impede accurate control, and since it is an indirect method, the accuracy is not very good. 11m
However, at any position after the tip, flfflJlil
is difficult.

Therefore, several methods (direct methods) and devices have been proposed in which an external force detector is installed in the gap between the roll chock and the housing post to directly detect the horizontal movement of the roll chock due to external force or the force with which the roll chock presses against the housing post. .

However, this method (device) requires at least two pressure detection devices in order to be effective in detecting both the front external force and the rear external force, which not only imposes a heavy economic burden, but also requires the use of a rolling mill. It is clear that the structure is complex and poses various problems in terms of maintenance, management, and inspection.

Also, from the viewpoint of detection accuracy, the roll chock actually causes a meandering movement between the left and right housing posts, and this movement acts as a disturbance directly on the pressure detection device, causing a lack of accurate control. (This meandering phenomenon occurs because there is a slight gap between the roll chock and the housing post.)

The purpose of the present invention is to eliminate the drawbacks of the conventional method as described above, use a control device with the simplest structure possible, and achieve a tension control system that is comparable to the conventional method in terms of response speed, reliability, stability, and accuracy. An object of the present invention is to provide a method and apparatus for detecting compressive force.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

First, FIG. 1 shows a schematic configuration diagram of a rolling mill for explaining the principle of the detection method according to the present invention. In the figure, 1 is a roll chock, 2 is a housing post, 3 is a roll, 4 is a rolled material, Reference numeral 5 indicates a pressure detector, and reference numeral 6 indicates a roller bearing.

First, when the roll 3 is in an unloaded state, a predetermined constant pressure is applied to the pressure detector 5 in advance.

Various methods can be used to achieve this constant pressure, as will be described later.
Its size is approximately 1/10 to 1/100 of the rolling load.
is necessary.

In other words, if it is more than this, too much load will be applied to the housing post, and if it is less than this, it will be difficult to distinguish it from the disturbance accompanying the meandering motion as described above.

Further, the roller bearing 6 is provided to reduce the frictional force between the roll chock 1 and the housing post 2 as much as possible.

FIG. 2 is a diagram illustrating how the output signal of the pressure detector 5 to which a constant pressure is applied in this manner changes depending on the presence or absence of external force during rolling.

First, in a state where rolling is not being performed, the pressure detector 5
Since a constant pressure is applied to , the output signal is constant at level Ta.

Rolling starts at time t1, and when a load is applied, a slight waveform occurs.

If no tension or compression force is applied to the rolled material 4, the output signal will have the waveform indicated by a at time t□-t4 during rolling.

And when a tension or compression force occurs at time 12,
The output signal changes to a waveform indicated by b or C.

The waveform has forward tension 1f11. Or, when the backward compression force tb□ is effective, that is, when the pressure from the rolled material 4 is applied to the pressure detector 5, the output signal increases to Tb.

Further, waveform C indicates a case where the front compressive force tf2 or the rear tension force tb2 is applied, that is, when the pressure applied to the pressure detector 5 is reduced by the rolled material 4, the output signal drops to Tc.

Note that control is performed based on the output of this pressure detector, and if the tension and compression forces disappear at time t3, the output signal becomes Ta again.

As described above, according to the present invention, front and rear external forces can be directly detected by providing a pressure detector only on one side of the roll chock.

Next, in order to carry out the tension/compression force detection method according to the present invention, an embodiment of a constant pressure applying device for applying constant pressure to a pressure detector is shown in FIGS. 3 to 5.

In FIGS. 3 to 5, the same components as in FIG. 1 are given the same symbols.

First, FIG. 3 shows a case where a disc spring 1 is used as a constant pressure applying device.

In this case, the spring 7 and the pressure detector 5 may be integrated, but if this is not possible, it is necessary to set them on the opposite side from the pressure detector 5 as shown in the figure.

FIG. 4 shows a case where a small hydraulic load cell 8 is used.

Although it has some drawbacks in detection sensitivity and accuracy, it has the advantage of having a simple structure and being able to adjust the preload.

FIG. 5 shows that the housing post 2 is penetrated by the mandrel 9,
This is a case where a mainspring spring 10 is used.

As for the structure, for example, an annular pressure detector 5 is installed between the roll chock and the housing, and a mandrel (
As shown in the figure, screw the bolt) 9 into the roll chock and use the force of the spring to attach the roll chock 1 to the housing post 2.
It was designed to force the

Note that the pressure detector may be installed on the inlet side, the outlet side, or the driving operation side, or may be installed appropriately.

Further, although the above explanation has been limited to applying pressure to the pressure detection device, the principle is the same even if tension is applied instead of pressure.

As described above, according to the present invention, since only one pressure detector is required, the configuration is simple and extremely economical.

Furthermore, since signals directly proportional to tension and compression forces can be obtained, it is very effective for continuous tension-free and compression-free control.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a rolling mill for explaining the present invention in detail, Fig. 2 is a drawing for explaining the detection method according to the present invention, and Figs. 3 to 5 are constant pressure used in the present invention. Examples of additional devices are shown: 0 1...Roll chock, 2...Housing post, 3...Roll, 4...Rolled material, 5... ...Pressure detector, 6 ...Roller bearing, 1 ... Disc spring, 8 ... Curved hydraulic load cell, 9 ... Curved shaft, 10 ... Spring.

Claims (1)

[Claims] 1. In a continuous rolling mill consisting of a plurality of stands, a predetermined pressure is constantly generated between a roll chock and a housing post on one side, and the pressure is varied by the tension and compression forces generated between the stands. Method 2 for detecting tension and compression forces between stands in a continuous rolling mill, characterized in that the tension and compression forces between the stands are detected by measuring changes in pressure 2 Continuous rolling mill consisting of a plurality of stands a pressure detector for detecting the pressure acting between the roll chock and the housing post on one side, and a constant pressure applying device for constantly producing a predetermined constant pressure between the roll chock and the housing post, An additional device applies a predetermined constant pressure to the pressure detector in advance to generate a predetermined output in the pressure detector during rolling with no tension and no compression, and from changes in the output of the pressure detector, the tension and compression between the stands can be determined. A device for detecting tension/compression force between stands in a continuous rolling mill, characterized by detecting force. 3. The continuous rolling apparatus according to claim 2, characterized in that the constant pressure applying device is configured to apply a predetermined constant pressure between the roll chock and one housing post using spring pressure or hydraulic pressure. A device for detecting tension/compression force between stands in a machine.