CN115351093A - Anti-steel-piling control method and system for tandem rolling mill - Google Patents

Abstract

The invention discloses a method and a system for controlling steel piling prevention of a tandem rolling mill, wherein the method comprises the following steps: counting the torque values of various rolled varieties and determining the maximum torque change value; acquiring an actual value of motor torque of a rolling mill and taking an absolute value; determining a set value of the maximum torque; and comparing the actual value of the motor torque of the rolling mill with the set value exceeding the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running. The invention can effectively predict the occurrence of steel piling accidents and improve the operation rate.

Description

Anti-steel-stacking control method and system for tandem rolling mill

Technical Field

The invention relates to the technical field of automatic control, in particular to a method and a system for controlling steel piling prevention of a tandem rolling mill.

Background

At present, international mainstream designs of rolling mills for rolling heavy rails, section steel and the like in steel mills in China all adopt a multi-frame cascade mode for rolling, and the tandem rolling mills are characterized in that steel piling accidents can be caused between frames due to improper adjustment of guard plates between the rolling mills and improper technological parameters of the rolling mills, so that the processing time of production accidents is prolonged. The existing measures for preventing steel piling include a method for detecting the head position of a billet, a method for installing a mechanical protection device for preventing steel piling between rolling mills and the like, and the measures generally have some effects, but have more defects, namely, the response speed is not fast enough, and misoperation of a steel piling procedure is easy to occur.

Disclosure of Invention

In view of this, the invention provides a method and a system for controlling steel piling prevention of a tandem rolling mill, which can reduce economic loss caused by steel piling accidents to the maximum extent.

The invention provides a steel piling prevention control method of a tandem rolling mill, which comprises the following steps: counting the torque values of various rolled varieties and determining the maximum torque change value; acquiring an actual motor torque value of the rolling mill and taking an absolute value; determining a set value of the maximum torque; and comparing the actual value of the motor torque of the rolling mill with the set value exceeding the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running.

Further, the step of counting the torque values of various rolled varieties and determining the maximum torque change value comprises the following steps: counting the torque values of various rolled varieties; calculating torque change values among various varieties based on the torque values of various rolled varieties; and comparing the torque change values among the varieties, and screening out the maximum torque change value.

Further, the step of determining the over-maximum torque set point comprises: setting an over-maximum torque fault multiple; and multiplying the maximum torque fault multiple by the maximum torque change value to obtain the maximum torque set value.

Further, the step of comparing the actual value of the motor torque of the rolling mill with the set value of the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running comprises the following steps: and when the actual value of the motor torque of the rolling mill is larger than the set value of the maximum torque, generating a control instruction to control the main transmission of the rolling mill to stop running.

A second aspect of the present invention provides a system for controlling a tandem mill against steel piling, the system comprising: the torque change maximum value determining module is used for counting torque values of various rolled varieties and determining the torque change maximum value; the motor torque acquisition module is used for acquiring the actual motor torque value of the rolling mill and taking an absolute value; the maximum torque set value exceeding determining module is used for setting the maximum torque fault multiple and calculating the maximum torque set value; and the steel piling prevention control module is used for comparing the actual motor torque value of the rolling mill with the set value of the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running.

Further, the torque change maximum determination module determines a torque change maximum, including: counting the torque values of various rolled varieties; calculating torque change values among various varieties based on the torque values of various rolled varieties; and comparing the torque change values among the varieties, and screening out the maximum torque change value.

Further, the over-maximum torque set point determination module calculates an over-maximum torque set point, including: setting an over-maximum torque fault multiple; and multiplying the maximum torque fault multiple by the maximum torque change value to obtain the maximum torque set value.

According to the steel piling prevention control method and system for the tandem rolling mill, the motor torque change response is fast, so that the steel piling accident can be effectively predicted, the production accident time can be effectively reduced, and the operation rate is improved.

Drawings

For purposes of illustration and not limitation, the present invention will now be described in accordance with its preferred embodiments, particularly with reference to the accompanying drawings, in which:

FIG. 1 is a graph of a PDA data curve analysis of line 2 from a factory;

FIG. 2 is a graph of the data of the PDA when a steel stacking accident occurs on the CCS of No. 2 line;

FIG. 3 is a schematic diagram of an odd pass material inspection;

FIG. 4 is a schematic diagram of even pass material detection;

FIG. 5 is a schematic view of a mechanical protective device;

fig. 6 is a flowchart of a method for controlling a steel stack prevention of a tandem mill according to an embodiment of the present invention;

FIG. 7 is a PDA graph of a steel stacking accident of the tandem rolling mill in a steel rail beam-wrapping plant;

fig. 8 is a schematic structural diagram of a steel piling prevention control system of a tandem rolling mill according to another embodiment of the present invention.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a detailed description of the present invention will be given below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and features of the embodiments may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, and the described embodiments are merely some, but not all embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

And (4) counting the expected torque of each variety of large steel products of a certain plant, and analyzing the previous case of steel piling accidents.

FIG. 1 is a graph of a PDA data curve for line 2 from a factory. Referring to fig. 1, the circle is marked with data of the steel billet, torque and rolling force of the previous steel billet which is normally rolled, and viewed from the data: in normal rolling, the maximum torque of the E stand was 22.64%, the average was 15.1, the maximum rolling force was 822.00, and the average was 565.078.

Fig. 2 is a PDA data curve when a steel piling accident occurs on the CCS line No. 2, and it can be seen that the main transmission torque and the rolling force of the E rolling mill change rapidly at the moment of the steel piling accident, the rolling force is 1666 times as large as that of normal rolling, and the maximum torque is 75.15% as large as normal rolling. Is 3.2 times of that in normal rolling. When operators find the steel pile, the rapid stopping method is adopted, so that the accident expansion is avoided. However, from the on-curve data analysis: when the steel piling accident happens and the main transmission stops rotating, the main transmission rotates for about 7 seconds at the speed of 1.7 m/s, namely, the billet is piled between E → UF by 1.7 x 7=11.9 m.

From the analysis results, the mode and the method are not feasible by relying on manual judgment of steel stacking and rapid shutdown, and the human reaction speed and the responsibility are uncontrollable compared with the advantages and the disadvantages of other control methods

(1) Material detection method

Referring to fig. 3, odd pass:

(1) UR → E, after the material No. 8 is lightened for 5 seconds, if the material No. 9 is not lightened, the steel holding program is triggered.

(2) E → UF: after the No. 9 material lights for 4 seconds, if the No. 10 material does not light, trigger the steel-holding program.

Referring to fig. 4, even pass:

(1) UF → E: after the material No. 10 is lightened for 5 seconds, if the material No. 9 is not activated, a steel holding program is triggered.

(2) E → UR, after the material No. 8 is lighted for 4 seconds, if the material No. 7 is not lighted, the steel holding program is triggered.

The protection mode has the advantages and the disadvantages that:

the advantages are that: (1) the program design is simple, and the post personnel can understand well; (2) and a detection element is not required to be newly added, and capital investment is not required.

The disadvantages are as follows: (1) the response of the steel holding-out triggering program is not sensitive enough, and great loss can still be caused when steel holding-out accidents occur. (2) Steel holding procedures may be triggered by external influences, such as: and detecting the reasons of component failure, steel clamping of a rolled piece when the rolled piece bites into a rolling mill and the like.

(2) Mechanical protection device

Referring to fig. 5, the protection method has the advantages and disadvantages:

the advantages are that: (1) the program design is simple, and the post personnel can understand well; (2) and a detection element is not required to be newly added, and capital investment is not required.

The disadvantages are that: (1) the installation structure is complex, and the steel piling prevention device can influence the operation of operators in the rolling mill; (2) the steel piling in the upwarp direction of the steel billet can be effectively prevented, but the steel piling accidents in other three directions cannot be prevented.

Fig. 6 is a flowchart of a method for controlling steel piling prevention of a tandem mill according to an embodiment of the present invention. The following detailed description of specific embodiments of the present invention is provided in connection with the accompanying drawings.

Referring to fig. 6, the method for controlling the anti-piling of steel in the tandem rolling mill includes the steps of:

and S100, counting the torque values of various rolled varieties and determining the maximum torque change value.

In this example, the torque values of various types of rolling in the plant product outline (as shown in table 1) were counted, and the maximum value of the torque variation was determined.

TABLE 1 CCS Rolling various kinds of torque statistics table

In this embodiment, in step S100, the step of determining the maximum value of the torque variation includes:

s101, counting and rolling various kinds of torque values;

s102, calculating torque change values among various varieties based on the torque values of various rolled varieties;

s103, comparing the torque change values among the varieties, and screening out the maximum torque change value.

And S200, acquiring an actual motor torque value of the rolling mill and taking an absolute value.

And because the torque is a negative value when the reciprocating rolling mill rotates reversely, acquiring an actual value of the torque of the motor and taking an absolute value.

And S300, determining the set value of the maximum torque.

In this embodiment, in step S300, the step of determining the set value of the over-maximum torque includes:

and S301, setting the maximum torque fault multiple.

And S302, calculating an over-maximum torque set value according to the over-maximum torque fault multiple and the maximum torque change value.

In this embodiment, the maximum torque set value is obtained by multiplying the maximum torque change value by the maximum torque fault multiple.

And S400, generating a control instruction based on the set value of the maximum torque and the actual value of the motor torque of the rolling mill so as to control the main transmission of the rolling mill to stop running.

In this embodiment, whether the actual motor torque value of the rolling mill is greater than the set value of the maximum torque is determined by comparing the actual motor torque value of the rolling mill with the set value of the maximum torque.

And if the actual value of the motor torque of the rolling mill is greater than the set value of the maximum torque, sending a stop instruction to a main transmission controller of the rolling mill to control the main transmission of the rolling mill to stop running.

According to the torque formula: t =9550P/N;

motor power formula: p =1.732 u × i cos Φ;

wherein T is torque, P is power, and N is motor angular velocity. Under the condition of constant rotating speed, the power of the motor is in direct proportion to the current, and the torque is in direct proportion to the power.

FIG. 7 is a PDA curve record of steel piling accident of tandem rolling mill in steel rail beam plant, from which it can be seen that the instantaneous torque of steel piling is changed sharply.

The motor torque can be predicted during normal rolling, and the main transmission can be stopped instantly when a steel piling accident happens according to the change of the torque, so that the loss of the steel piling accident is reduced.

According to the anti-steel-piling control method for the tandem rolling mill, the motor torque change response is fast, so that the occurrence of steel-piling accidents can be effectively predicted, the production accident time can be effectively reduced, and the operation rate is improved.

Fig. 8 is a schematic structural diagram of a steel piling prevention control system of a tandem rolling mill according to another embodiment of the present invention. The following detailed description of specific embodiments of the present invention is provided in connection with the accompanying drawings.

Referring to fig. 8, the anti-piling control system 500 of the tandem mill includes the following steps:

the torque change maximum value determining module 501 is configured to count torque values of various types to be rolled, and determine a torque change maximum value.

And a motor torque obtaining module 502, configured to obtain an actual motor torque value of the rolling mill and obtain an absolute value.

The maximum torque exceeding set value determining module 503 is configured to set a maximum torque exceeding fault multiple and calculate a maximum torque exceeding set value.

And the steel piling prevention control module 504 is used for comparing the actual motor torque value of the rolling mill with the set value of the maximum torque and generating a control instruction so as to control the main transmission of the rolling mill to stop running.

In this embodiment, the maximum torque variation module 501 counts the torque values of various rolled products in the outline of the plant product, and calculates the maximum torque variation.

In this embodiment, the maximum torque exceeding setting value determining module 503 sets a maximum torque exceeding fault multiple, multiplies the maximum torque change value by the maximum torque exceeding fault multiple, and calculates to obtain a maximum torque exceeding setting value.

According to the steel piling prevention control system of the tandem rolling mill, the motor torque change response is fast, the steel piling accident can be effectively predicted, the production accident time can be effectively reduced, and the operation rate is improved.

The above-described embodiments should not be construed as limiting the scope of the invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may occur depending on design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (7)

1. A control method for preventing steel piling of a tandem rolling mill is characterized by comprising the following steps:

counting the torque values of various rolled varieties, and determining the maximum torque change value;

acquiring an actual motor torque value of the rolling mill and taking an absolute value;

determining a set value of the maximum torque;

and comparing the actual value of the motor torque of the rolling mill with the set value exceeding the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running.

2. The method for controlling the anti-piling of the steel in the tandem rolling mill according to claim 1, wherein the step of statistically rolling the torque values of various types and determining the maximum value of the torque variation includes:

counting the torque values of various rolled varieties;

calculating torque change values among various varieties based on the torque values of various rolled varieties;

and comparing the torque change values among the varieties, and screening out the maximum torque change value.

3. The method of claim 1, wherein the step of determining the over-maximum torque set point comprises:

setting an over-maximum torque fault multiple;

and multiplying the maximum torque fault multiple by the maximum torque change value to obtain the maximum torque set value.

4. The method for controlling the anti-piling of the steel in the tandem mill according to claim 1, wherein the step of comparing the actual value of the motor torque of the mill with the value exceeding the maximum torque set value to generate the control command to control the main transmission of the mill to stop running comprises:

and when the actual value of the motor torque of the rolling mill is greater than the set value of the maximum torque, generating a control instruction to control the main transmission of the rolling mill to stop running.

5. A steel piling prevention control system of a tandem rolling mill is characterized by comprising:

the torque change maximum value determining module is used for counting torque values of various rolled varieties and determining the torque change maximum value;

the motor torque acquisition module is used for acquiring the actual motor torque value of the rolling mill and taking an absolute value;

the over-maximum torque set value determining module is used for setting over-maximum torque fault multiples and calculating over-maximum torque set values;

and the steel piling prevention control module is used for comparing the actual motor torque value of the rolling mill with the set value of the maximum torque to generate a control instruction so as to control the main transmission of the rolling mill to stop running.

6. The anti-windup control system of a tandem mill according to claim 5, wherein the torque variation maximum value determination module determines a torque variation maximum value, including:

counting the torque values of various rolled varieties;

calculating torque change values among various varieties based on the torque values of various rolled varieties;

and comparing the torque change values among the varieties, and screening out the maximum torque change value.

7. The system of claim 5, wherein the over-max-torque-setting-value determining module calculates an over-max-torque-setting-value, comprising:

setting an ultra-maximum torque fault multiple;

and multiplying the maximum torque fault multiple by the maximum torque change value to obtain the maximum torque set value.

Images