JPS6234613A - Rolling control method for bar material - Google Patents

Abstract

PURPOSE:To enable a correct rolling control always by supporting by an ascending and descending roll so as to cause no tensile force more than the prescribed by the dead weight of a suspension loop in case of controlling the number of roll rotations by the loop suspension quantity of the bar stock between rolling stands. CONSTITUTION:The loop vertical quantity of the stock W to be rolled is measured by a detector 10 in case of drawing the stock W to be rolled continuously by plural rolling stands 1, 2. This observation value delta and target value delta0 are compared by a comparing part 15, the deviation epsilon thereof is inputted into an operation control part 13 and control signals Cu, Cd are outputted to each rolling stand 1, 2 for controlling so that this deviation epsilon becomes zero. In this case an air cylinder 24 is controlled via the solenoid value 27 for moving in vertical direction and the solenoid valve 26 for pressure changing with a pressure adjusting valve 28 by supporting by providing an ascending and descending roller 20 in the area where the loop 8 of the stock W to be rolled causes more than the prescribed tensile force by its dad weight. The tensile force by the dead weight of the stock W to be rolled suspending the loop is eliminated by adjusting the supporting pressure and vertical position of the ascending and descending roll 20 by a piston rod 25.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention involves forming a loop between the rolling stands when a strip is continuously stretched using a plurality of rolling stands, and using the amount of suspension of the loop as a control signal. The present invention relates to an improvement in a method of controlling the rotation speed of upstream or downstream rolling rolls.

(Background of the Invention) In recent years, there has been a strong desire for a rolling method that can achieve high dimensional accuracy over the entire length so that rolled rod and wire products can be directly cooled and forged. Between stands with relatively long spans, including between rows,
By focusing on the loop of the strip material, which was conventionally recognized only as the buff 7, and controlling the amount of suspension of this loop in response to the axial force (a general term for the tension or compression force of the strip material between the stands), A simple and highly accurate method for controlling axial force was provided (patent application filed in 1983).
-238502 (Japanese Unexamined Patent Publication No. 130411/1983)).

However, in such a method, the target value of the loop suspension amount is calculated in advance based on the steel type, cross-sectional shape and average temperature of the material to be rolled, with respect to the target axial force between the rolling stands.
Since we use a method of controlling the rotation speed of the rolling rolls so that there is no deviation from the measured loop suspension amount, if there is a problem with the setting parameters, the correlation between the loop suspension amount and the axial force will decrease. Despite the problem of not being able to accurately control rolling, especially in the rolling of long steel products, there are cases where the cross-section of the rolled material is large or where the distance between the rows is large, such as between the rough rolling row and the intermediate rolling row. Large area (generally 10-15m with crop and fuggle shears)
In the loop, a tensile force is generated due to the weight of the rolled material that forms the loop, and the shape and dimensions of the rolled material are greatly affected, and it is not possible to set accurate parameters for the cross-sectional shape, resulting in a delay in control response. It has been found that there are cases where problems occur in terms of control accuracy.

(Problem of the Invention) The present invention aims to improve the above-mentioned rolling control method so that it can withstand the strict dimensional accuracy requirements of the current m5-roll.

(Summary of the Invention) The present invention provides a method for forming loops that occur in places where the cross-section of the rolled material is large during rolling of long steel products, or in places where the distance between the rows is large, such as between the new rolling row and the intermediate rolling row. The problem is that the tensile force that exceeds the weight of the rolled material that forms the loop has an unnatural effect on the shape and dimensions of the rolled material, making it impossible to set accurate dimensions. Focusing on the fact that it is superior in terms of control technology to eliminate the tensile force caused by the rolling process, we have focused on the fact that it is superior in terms of control technology to eliminate the tensile force caused by the rolling process. The material to be rolled is controlled and supported so as to relieve the tensile force due to its own weight, thereby solving the problem of changes in the cross-sectional shape and dimensions of the material to be rolled, and preventing delay in control response. The purpose is to perform accurate rolling control of long steel.

Hereinafter, the present invention will be explained based on the accompanying drawings showing specific examples thereof.

(Example) FIG. 1 is a schematic block diagram of a rolling apparatus to which the rolling control method according to the present invention is applied, and FIG. 2 is a schematic diagram of a control device for lifting rollers that support a rolled material.

In the drawing, 1 is an upstream rolling roll, 2 is a downstream rolling roll having a rotational axis perpendicular to the rotational axis of the rolling roll 1, and the rolled material 3, which is a strip, is rolled in the drawing based on a pass line 4. Proceed from left to right. Near the exit of the rolling roll 1,
An exit roller 5 for the id is arranged so as to be in contact with the pass line 4, and a large mouth roller 6 is arranged near the entrance of the rolling roll 2 on the same side of the pass line 4 as the exit roller 5. The positional relationship between the rolling rolls 1 and 2 and each roller 5 and 6 is as follows:
It is symmetrical with respect to the center of the distance between the stands, that is, with respect to the imaginary line 7. For the material to be rolled 3, the rolling rolls 1,
2 are the left and right fixed ends, and the exit roller 5 and the entrance roller 6
each forms a free end that provides displacement, and the rolled material 3
forms a symmetrical loop 8 at this exit and the large roller 5.6WA.

10 is a suspension amount detector for detecting the suspension amount of the loop 8; 11
3 is a computer as an electronic calculation control means, 12 is a parameter setting board for manually setting parameters, and the computer 11 includes at least a calculation control section.
, a data storage section 14 , and a data comparison section 15 . The data storage unit 14 includes a table of Young's modulus specified by the steel type and average temperature of the material to be rolled 3, a target value table of the loop suspension amount uniquely determined for the material to be rolled 3t, and other tables or tables. Individual data is stored.

Information specifying the distance between the stands from the setting panel 12, that is, parameters such as the distance between the rolling rolls 1 and 2, the distance between the rollers 5 and 6, the steel type of the rolled material 3, cross-sectional shape, average temperature, target axial force, etc. Input the parameter group p. Arithmetic control unit 43
In response to this, the Young's modulus table in the storage unit 14 is indexed, and other inlet data are also referred to to determine the target value δ of the loop suspension amount corresponding to the target axial force. is determined and output to the comparison section 15. In the comparison section 15, the target value δ.

and the actual measurement value δ from the suspension amount detector 10, and input the deviation ε to the calculation control unit 13. The calculation control unit 13 is
According to this deviation ε, the control signal C is set so that the deviation ε becomes zero.
The control signal Cu that outputs the control signal u or the control signal Cd is secondarily given to the upstream roll 1, but subsequent to the control of the roll 1, successive control is performed on the entire upstream roll. be exposed. The same applies to the control signal Cd.

In the present invention, as an area where a tensile force exceeding a predetermined level (1) is generated due to the weight of the material to be rolled suspended in a loop between the rolling stands, for example, the areas are arranged in the rough rolling row 1 and the intermediate rolling row 2 in long steel rolling. Grand Looper 5, 6
An elevating roller 20 that supports the rolled material W suspended in a loop is provided at an intermediate position between the two, and controls and supports the rolled material W so as to eliminate the tensile force due to its own weight. For more information,
The lifting roller 20 extends in the vertical direction and is provided so as to be able to rise and fall with respect to the id 21 via a support member 22.
is connected to the piston rod 25 of the air cylinder 24 via the arm 23, and the air cylinder is arranged with a pressure change solenoid valve 26, a solenoid Y valve 27 for vertical movement, and a pressure adjustment valve 28 as shown in the figure. The regulating valve 28 is set in advance to a predetermined pressure according to the weight of the rolled material suspended in a loop, and the pressure changing solenoid V valve 26
And the solenoid valve 27 for vertical movement is machined to adjust the support pressure and the lifting position of the lifting roller to control and support the rolled material so as to eliminate the tensile force due to the weight of the rolled material suspended in a loop. , 4 indicates a pass line.

(Operations and Effects of the Invention) As is clear from the above explanation, according to the present invention, when continuously stretching a strip using a plurality of rolling stands,
With respect to the target axial force between the rolling stands - Compare the target value of the loop suspension amount calculated in advance based on the steel type, cross-sectional shape and average temperature of the material to be rolled and the actually measured loop suspension amount, and determine the deviation. When controlling the rotation speed of the rolling rolls so as to eliminate the tensile force caused by its own weight, in order to control and support the rolled material so as to eliminate the tensile force due to its own weight, it is necessary to In areas where the distance between rows is large, such as between rows, a tensile force is generated due to the weight of the rolled material that forms the loop, and the shape and dimensions of the rolled material are greatly affected, making it difficult to set accurate parameters for the cross-sectional shape. The problem of not being able to do it is resolved,
Even if the target axial force is set using the actually measured loop suspension amount as a control signal, rolling control can always be performed accurately, so this method is revolutionary as a rolling control method for long steel products.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a rolling apparatus to which the rolling control method according to the present invention is applied, and FIG. 2 is a schematic diagram of a control device for lifting rollers that support a rolled material. 1...Rough rolling row, 2...Intermediate rolling row, 20...Elevating roller.

Claims (1)

[Claims] (1) When a strip is continuously stretched by a plurality of rolling stands, a loop is formed between the rolling stands, and the amount of suspension of the loop is used as a control signal to control the rotation speed of the upstream or downstream rolling rolls. In an area where a tensile force of more than a predetermined value is generated due to the weight of the rolled material hanging in a loop between the rolling stands, an elevating roller (20) is provided to support the rolled material suspended in a loop, so as to eliminate the pulling force due to the weight. A method for controlling the rolling of a strip material, characterized in that the material to be rolled is controlled and supported.