Method of rolling mill operation with edge detection

FIELD: process engineering.

SUBSTANCE: strip 2 in multi-stand mill passes sequentially through stands 1. Strip 2 is fed to every stand 1 with respect to central line of rolling with known adequate shift V of its head part and with known adequate inclination of said part SE at inlet side so that head part 8 gets out of stand 1 with appropriate shift V, head part inclination SA at outlet side and curvature K at outlet side. Wedge formation in the strip is ruled out by eliminating difference in stretching stresses between strip edges due to that fact that inclination SA at outlet side is defined from inclination SE on inlet side and reduction in stand 1. Strip head part curvature K at outlet side is defined from the results of appropriate measurements and other appropriate data. Appropriate curvature K of strip head part at outlet side is used to define appropriate control effect S for appropriate mill stand 1 and/or stand 1 immediately downstream thereof for control over said stand 1.

EFFECT: higher quality of rolled stock.

20 cl, 12 dwg

 

The proposed invention relates to a method of rolling strip rolling mill, containing a number of rolling stands through which pass through the strip, and the strip is always relative to the center line of the rolling - in each of the rolling stands is injected with a known corresponding shift of the head part of the strip and with the known corresponding tilt of the head part of the strip on the input side, so that the head part of the strip from the respective rolling stands out, with a corresponding shift of the head part of the band corresponding to the inclination of the head part of the strip on the output side and with a corresponding curvature of the head part of the strip on the output side.

The proposed invention also relates to a computer program that contains native code that is directly executable by the appliance mnogoluchevogo rolling mill, and the performance of which by means of a control device is that the control device controls the rolling mill in accordance with this method.

The proposed invention also relates to the media data stored on the data carrier with a computer program of the above type.

In addition, the proposed invention relates to the control device mnogoluchevogo rolling the Tana, moreover, the control device is designed in such a way that it controls the rolling mill in accordance with the above method.

Finally, the proposed invention relates to rolling mill and rolling mill contains a number of rolling stands through which pass through the strip, and rolling mill includes a control device of the above type so that the rolling mill is operated in accordance with the method of the above type.

During rolling of the strip between the strip edge can be the difference of tensile stresses. One of the major reasons of the difference of tensile stresses is the wedge in the band profile. The wedge profile strips can have different reasons. For example, the strip before rolling may have a wedge-shaped profile. Alternatively, the wedge may be due to rolling in the deformation zone (when rolling). For a message the band wedge-shaped profile may have several reasons. For example, the strip may have a wedge-shaped temperature distribution, the strip can enter the zone of deformation is not in the center, or the zone of deformation can be wedge-shaped. The possible combinations of these (and other) reasons.

In the prior art it is known that to identify emerging in the band differences tensile stresses between the AC is hard two rolling stands can accommodate pelletization, which on both side brackets equipped with sensors efforts. Normal peredergivali have, however, only one-way measurement efforts and therefore give only the total force, but not a differential force between the two edges of the strip. Therefore, without peladinhas with double-sided sensors effort distribution of tensile stress in the band is unknown. Therefore, it is impossible to predict in what direction the band is rejected when the base strip is produced from one of the rolling stands. In particular, the rear rolling mill mnogoluchevogo rolling mill adjustment of a variance or other actuators rolling stands, located directly behind the respective rolling stand, it is possible not fast enough to resolve the collision of the base strip with the side rail rolling mill.

In the prior art, moreover, it is known that the operator of the rolling mill with the introduction of the band visually tracks the head of the band, and - according to his personal perception of the strip position and the waviness of the strip - regulates the installation of rolling stands, directly challenging the head part of the band (in particular, the position of the deflection rolls).

The present invention is to create opportunities through which the wedge in the band MoE is et to be recognized and/or it can be avoided, and/or the difference between the tensile stresses between the edges of the strip can be detected and/or they can be avoided, without requiring for this peladinhas with bilateral definition effort.

The objective of the inventive method is solved by a method with the characteristics of paragraph 1 of the claims. Preferred embodiments of the method presented in dependent clauses 2-12.

In accordance with the invention, in the method of the above type is provided,

the inclination of the head part of the strip on the output side is determined based on the inclination of the head part of the strip on the input side and the corresponding compression implemented in the respective rolling stand,

the corresponding curvature of the head part of the strip on the output side is determined on the basis of the respective measured data and other relevant data

that, with appropriate curvature of the head portion of the strip on the output side is determined by an appropriate control action for the respective rolling stand and/or rolling stands directly next to the respective rolling stand, and

the respective rolling stand and/or rolling crate, immediately following the respective rolling stand, are managed in accordance with certain relevant is sending the influence.

In a first possible implementation of the relevant invention of the method provides that by proper device positioning, located between the respective rolling stand and the rolling stand directly next to the respective rolling stand, is determined by a corresponding shift of the head portion of the strip between the rolling stands and that the corresponding measured data correspond with the appropriate definite shift the head part between the rolling stands, and other relevant data with the corresponding shift of the head part of the strip and the corresponding inclination of the head part of the strip on the output side. By such a mode of action determination of the curvature of the head part of the strip you can implement a particularly simple and reliable method with optimal cost. Device location determination may be performed in any way, if it has the desired functionality. For example, the appropriate device positioning can be performed as a linear scanner (infrared scanner, diode line scanner etc) or as the camera forming the image. There might also be other run. Typically, device positioning is made the same. However, it is not necessarily required. The mouth of austo positioning can also be performed respectively individually from one zone between the rolling stands up to the other zone between the rolling stands.

Within the last named execution of the proposed invention, therefore, in the case of device positioning between every two rolling stands, for example, it is possible, immediately after the definition of shift between the rolling stands for the respective rolling stands, to determine the shift of the head part of the strip and the tilt of the head part of the strip on the input side for rolling stands directly next to the respective rolling stand, to determine the control command for rolling stands directly next to the respective rolling stand, and to issue a control command, at the latest at the entrance of the head part of the strip in the rolling mill, directly following the respective rolling stand, in the rolling mill, directly following the respective rolling stand. The management team in this case is determined so that the shift of the head part of the strip, tilt the head part of the strip on the output side and/or the curvature of the head part of the strip on the output side is reduced, so that the strip with respect to the center line of the rolling - centered.

In the preferred implementation of the proposed invention, however, provides,

a corresponding shift of the head part of the band corresponding to the tilt of the head part of the strip with the side exit and the corresponding curvature of the head part of the strip on the exit side of remembered

after entering the strip in the last rolling stand of the rolling mill, the strip between the stands of the rolling mill, is loaded with tension,

that stripe is always with respect to a center line of the rolling - in each rolling stand is included with the known corresponding shift of the band and is known for the corresponding slope of the strip on the input side, and from the respective rolling stands out, with a corresponding shift of the band corresponding to the slope of the strip on the output side and the corresponding curvature of the strip on the output side,

the slope of the strip on the output side is determined based on the slope of the strip from the entrance and implemented in the respective rolling stands compression,

through the device positioning, placed directly behind the respective rolling stand, is determined by a corresponding shift of the strip between the rolling stands for the band,

what with the corresponding shift of the band corresponding to the slope of the strip on the output side and the corresponding shift of the strip between the rolling stands is determined corresponding to the curvature of the strip on the output side and

that the appropriate control action is determined by applying the appropriate shift of the fringe, which is adequate slope streaks on the output side and the corresponding shift of the strip between the rolling stands.

Appropriate management team within the last three complete, in particular, is determined so that the appropriate control action counteracts deviations of the base strip at the exit of the founding bands of the respective rolling stands.

Is it possible that the respective rolling stand and/or rolling crate, immediately following the respective rolling stand, to a certain point in time are controlled according to a particular respective governing exposure, the band included in the respective rolling stand, is loaded with tension. In this case it is in principle equivalent, whether managed by the respective rolling stand or the rolling stand directly next to the respective rolling stand, in accordance with the specified control.

Alternatively, it is possible that the respective rolling stand or the rolling stand directly next to the respective rolling stand, to a certain point in time are controlled according to a particular respective governing exposure, the band included in the respective rolling stand, free from tension. And in this case it is in principle possible that the respective rolling stand manipulated is as defined by the respective governing influence. However, it is preferable in this case is controlled rolling crate, immediately following the respective rolling stand.

Shift the head part of the strip and the tilt of the head part of the strip from the entrance strip, a member of the first rolling stand, must be known. For example, it is possible to set the shift head band and/or tilting of the head part of the strip on the input side by means of respective guide devices on certain values, for example, to shift the head part of the strip and the tilt of the head part of the strip on the input side of 0. Alternatively, perhaps before the first rolling stand to place the device determining the position whereby the relevant values. Also possible in principle a combination of both events. For example, one of the two figures - shift head band and tilt the head part of the strip on the input side is set to a specific value and the other value is determined by determining the position of the strip.

The curvature of the strip between the following two immediately consecutive rolling stands is known by the relevant invention of the method of action. It is therefore possible, on the basis of the shift head band and tilt the head part of the strip from Vinodolski certain rolling stands, and the corresponding curvature of the head portion of the strip on the output side in conjunction with previously known distance to the immediately following rolling stands, to determine which shift the head part of the band and how tilting the head part of the strip from the entrance strip is included directly following rolling mill.

It is also possible, with appropriate shift of the head part of the band corresponding to tilt the head part of the strip on the output side and the corresponding curvature of the head portion of the strip on the exit side of the respective rolling stands, to determine the appropriate shift of the head part of the strip and the corresponding tilt the head part of the strip on the input side for rolling stands directly next to the respective rolling stand.

Alternatively, the determination of the shift of the head part of the strip between the rolling stands and defining the curvature of the head part of the strip on the output side on the basis of (among other things) a certain shift of the head part of the strip between the rolling stands is possible that the physico-mathematical model serves a corresponding shift the head part of the strip and the corresponding tilt the head part of the strip on the output side, the actual parameters of the stripes included in the respective rolling stand, and Polo is s, emerging from the respective rolling stand, and the variables and parameters of the respective rolling stand, and the corresponding curvature of the head part of the strip on the output side is determined by the physico-mathematical model.

This method has the advantage that it can be executed very quickly. In particular, the curvature of the head part of the strip on the output side can be determined almost simultaneously with the entrance of the head part of the strip in the respective rolling stand. Through this method of action, in particular, it is possible that a corresponding control intervention is determined immediately after the definition of the appropriate curvature of the head portion of the strip on the output side, and the respective rolling stand is controlled directly after the determination of the appropriate control action in accordance with the specified control.

Even better, both principal corresponding to the invention of a form of execution (i.e., the application device positioning, on the one hand, and the application of the model, on the other hand) to combine with each other. In this case there should be,

after determining the appropriate curvature of the head portion of the strip on the output side via a physical-mathematical model, the stage is niteline by proper device positioning, located between the respective rolling stand and the rolling stand directly next to the respective rolling stand, is determined by a corresponding shift of the head portion of the strip between the rolling stands, and

the corresponding curvature of the head part of the strip on the output side is adjusted based on the particular shift the head part of the strip between the rolling stands, the corresponding shift of the head part of the strip and the corresponding inclination of the head part of the strip on the output side.

In the preferred implementation of the last mentioned method, provided that the physical-mathematical model is adapted on the basis of the deviation determined on the basis of physico-mathematical model corresponding to the curvature of the head part of the strip on the output side of the adjusted corresponding to the curvature of the head part of the strip on the output side. The physical-mathematical model, thus trained, so defined on the basis of physico-mathematical model of the curvature of the head part of the strip on the exit side of the future rolled strips must be adjusted smaller, thus, the model agrees better with the real conditions.

As already mentioned, the issuance of certain of the appropriate control action to the rolling mill is Rakitovo mill possible at different points in time. In particular, it is possible that the rolling mill, directly following the respective rolling stand, operated at the latest when you enter the strip in the rolling mill, directly following the respective rolling stand, in accordance with certain appropriate control.

The corresponding curvature of the head part of the strip on the output side can be permanent. Alternatively, the corresponding curvature of the head part of the strip on the output side may vary with distance from the respective rolling stand, for example, be a linear function of the distance or be constant on sections.

This problem can be solved software-technically means of a computer program with signs of paragraph 15 of the claims and data carrier with signs of paragraph 16 of the claims.

In accordance with the invention, a computer program has native code, which can directly be executed by the control device mnogoluchevogo rolling mill, and the performance of which by means of a control device is that the control device controls the rolling mill in accordance with the method corresponding to the invention. A data carrier in accordance with the invention is designed so that it would dry up Anana computer program of the above type.

This problem can be solved by technical means through a control device mnogoluchevogo rolling mill with signs of paragraph 17 of the claims and rolling mill with signs of paragraph 19 of the claims.

In accordance with the invention the control device is designed in such a way that it controls the rolling mill in accordance with the method corresponding to the invention. The mill contains a number of rolling stands through which pass through the strip, and the control device of the above type so that the rolling mill is operated in accordance with the method corresponding to the invention.

The control device is preferably designed as a programmable software control unit that, when the work is done by a computer program of the above type.

Other advantages and features emerge from the following description of examples with reference to the drawings, in which, in schematic view, shows the following:

figure 1 - schematic representation mnogoluchevogo rolling mill,

figure 2 - rolling mill of figure 1 from above,

figure 3 - block diagram of the method

4 is a schematic representation of the rolling stands and strips, a member of the rolling mill and out of rolling stands,

5 is a schematic representation of a section rolling mill, which is limited to two rolling stands,

6 is a block diagram of the method

7 and 8 is a schematic representation of part of a rolling mill of figure 1,

Fig.9 is a schematic representation of a possible run of the mill of figure 1,

figure 10 - block diagram of the method

11 is a modification of figures 9 and

Fig is a block diagram of a method.

According to figures 1 and 2, the rolling mill has a number of rolling stands 1. Rolling mill, thus, performed as novokletevoj rolling mill. Through the rolling stands 1 when working rolling mill passed through the band 2. The mill also includes a control device 3, which is in the process of rolling strip rolling mill controls the rolling stands 1 and the other components of the rolling mill. The control device 3 is designed so that it is in the process of rolling operates a rolling mill according to the method, which is further explained in detail.

The control device 3 may be implemented as programmable hardware control device or programmable software control device. Typically, the control device 3 is designed as programmable software control device, which is in the process of rolling performed the computer program 4. A computer program has 4 in this case, the native code 5, which directly executes control device 3. Running native code 5 managing device 3 determines that the control device 3 controls the rolling mill according to the method corresponding to the invention.

Programming a control device 3 using the computer program 4 may be performed by any method. For example, the computer program 4 may already within the manufacturing control device 3 to boot to the control device 3. Alternatively, it is possible, for example, to submit to the control unit 3 of the computer program 4 through the connection between the computers. As the connection between the computers may be used, for example, a connection to a local area network (LAN) or the Internet. The connection between the computers 1 and 2 are not shown. Again alternatively, you can store a computer program 4 on the carrier 6 data and a computer program 4 submit to the control unit 3 through the medium 6 data. Just as an example, in figure 1 the carrier 6 data shown as CD-ROM. Alternatively, it can be made otherwise, for example, as a USB memory card or memory card.

The basic principle of the method corresponding to the invention, is illustrated on the more with reference to figure 3.

According to figure 3, the control device 3 selects the first stage S1 of the rolling mill 1, in which the band 2 is introduced first. Then, the controller 3 controls the step S2 rolling mill so that the band 2 when the observation relative to the centerline 7 rolling (see figure 2 and 4) is introduced into the selected rolling stand 1 with a known shift V head bands and known slope SE of the head of the track from the entrance. Based on the entry in the selected rolling stand 1 head part 8 of the strip 2 is out (actually only) of the selected rolling stand 1 with the shift of the V head of the band inclination SA parent part of the strip on the output side and a curvature To the head part of the strip on the output side.

Circumstances, on the basis of which the shift of the V head band and the slope of the SE head part of the strip on the input side is known for giving the first rolling stand 1 can be of different nature. For example, it is possible that there are corresponding, not shown in figure 1 and 2 vanes, on the basis of which the shift of the V head band and the slope of the SE head part of the strip on the input side must have certain values, for example, shift the head part of the strip V=0 and the slope of the head part of the strip on the input side SE=0. Alternatively or additionally it is possible to provide a device for the op is edeline, whereby the shift of the V head band and the slope of the SE head part of the strip on the input side before the first rolling stand 1 is determined and transmitted to the control unit 3.

At step S3, the control device 3, on the basis of slope SE of the head of the track from the entrance and implemented in the selected rolling stand 1 compression, determines the slope of the SA parent part of the strip on the output side. In particular, the slope of the SA parent part of the strip on the output side can be determined according to the equation:

Here vE and vA, in relation to the selected rolling stand 1, represent the speed of the strip 2 on the input side and output side. Speed vE and vA are associated with the compression through the continuity equation.

In addition, the control device 3 determines at step S4 curvature To the head part of the strip on the exit side of the strip 2. When this determination is made on the basis of measured data, and other data. As the measured data, and other data related to the currently selected rolling stand 1. Possible definitions hereinafter explained in more detail in connection with possible variants of implementation of the present invention.

At step S5 shift V head bands, tilt SA parent part of the strip on the exit side of the curvature To the head part of the strip with a hundred the ons output head part 8 of the strip when the selected rolling stand 1 - when comparing this rolling stand 1 is stored. Step S5 is set to a possible execution of the proposed invention.

It is possible, immediately before the definition of the curvature To the head part of the strip on the output side, to determine the control action S. This is shown in step S6. Also at step S6 presents that, in the alternative, it is possible to determine the control action S not directly, and before entering the strip 2 in the rolling mill 1, located directly after the selected rolling stand 1. In both cases, however, the step S6 is only optional and, therefore, figure 3 shows a dotted line. If it has, then control action S is determined by applying curvature To the head part of the strip on the output side, optionally with the additional use of tilt SA parent part of the strip on the output side and/or shift V head band. The control action S is defined for the selected rolling stand 1 and/or rolling stands 1, located directly after the selected rolling stand 1, if necessary, can also be determined by two distinguished from each other governors impact S, and each of both control actions S is determined for the selected rolling stand 1 and for rolling stands 1, is the th directly after the selected rolling stand 1.

If step S6 is present, the rolling mill 1, which is defined control action S, which is determined at the step S6, operated at the step S7 in accordance with a specific control S. However, the step S7, since it is the result of step S6 is only optional and, therefore, figure 3 shows a dotted line.

If defined control action S for the selected rolling stand 1 is defined, it is preferable that the control action S is defined immediately after the definition of the curvature To the head part of the strip on the output side, and the selected rolling stand 1 is controlled directly after the determination of the control action S, in accordance with a specific control s control S at step S7 is given to the rolling mill 1, located directly after the selected rolling stand 1, it is sufficient that the control action S is defined to a certain point in time to which the band 2 is not yet entered in the rolling mill 1 button directly after the selected rolling stand 1. As in this case, it is sufficient that the rolling stand 1, which is located directly after the selected rolling stand 1, operated in accordance with a particular control's the latest at the input of the strip in the rolling mill 1, located directly after the selected rolling stand 1.

At step 87 the controller 3 checks whether the currently selected rolling stand 1 of the last rolling stand 1 rolling mill 1. If it is not designated, the control device 3 selects at step S9 following the rolling mill 1 and defines for this rolling stands 1 shift V head band and the slope of the SE head of the track from the entrance. Since for small values of the curvature To the head part of the strip on the output side, which in practice is fairly ratio

for shear V" head part 8 lanes from the middle line 7 rolling as a function of distance x from the respective rolling stand 1. Therefore, using the values of KA, SA and V previous rolling stands 1 and the known distance G between the crates, you can easily determine the shift of the V head part of the band for the new selected rolling stand 1. The corresponding slope SE of the head of the track from the entrance to the new selected rolling stand 1 is obtained similarly using the proportion

moreover, the designation "SE" in equation (3) relates to the new selected rolling stand 1, and the notation "K" and "SA" refers to the immediately preceding rolling stand 1. X is PE is u this, to use the distance G between the crates.

After processing at step S9, the controller 3 returns to step S2.

If at step S8, a decision that has already selected the last rolling stand 1, the controller 3 moves to step S10. At the step S10 to the band 2, at least until it is between the rolling stands 1, is applied thrust. Then at step S11 continues rolling.

During rolling of the strip 2 when considering in relation to the center line 7 of the rolling - part of each of the rolling stands 1, with a corresponding shift V' bands and the corresponding slope SE' strip on the input side. In addition, the band 2 comes out of each rolling mill stand 1, with a corresponding shift V' line and the slope of the SA' strip on the output side and the corresponding curvature To' strip on the output side. When this shifts the V band, bending SE', SA' bands and curvature values To' strip on the output side should not be the same values as the values that were before those defined for the head part 8 of the strip. But really what values are known. They may also vary in time. However, values can be defined.

The values of V', SE' from the entrance to the first rolling stand 1 is known. Therefore, due to compression can determine the values of SA',' on the output side to the first rolling the fly 1. When known values SA',' on the output side for the respective rolling stand 1 can - similarly to the above equations (2) and (3) to determine the values of V', SE' from the entrance directly to the corresponding subsequent rolling stand 1. In particular, it is therefore possible to step S12 for each of the rolling stands 1 first register or to determine the values on the input side (shift V' band and the slope of the SE' strip on the input side), so that on the basis of the corresponding slope SE' strip on the input side and the corresponding compression implemented in the respective rolling stand 1, you can determine the slope of the SA' strip on the output side. It is also possible, similarly to the corresponding curvature To the head part of the strip on the output side, to determine the appropriate curvature To' strip on the output side.

For reliable implementation of step S12 is appropriate, the corresponding values of the curvature K, K' on the output side to determine possible in a reliable way. Therefore, the preferred way, respectively figure 5, provides that between every two rolling stands 1, preferably in the area of peladinhas 9 - posted by the appropriate device 10 position. By an appropriate device 10 positioning is possible to direct the military prior rolling stands 1 - to determine the appropriate shift VZ head part 8 of the strip between the mill for strip 2. On the basis of the corresponding shift VZ head part of the strip between the stands, the corresponding shift of the V head of the strip and the corresponding slope SA parent part of the strip on the output side to the head portion 8 of the strip during rolling stands 1, immediately preceding the relevant device 10 determining the position, in this case, you can determine the appropriate curvature To the head part of the strip on the output side on the basis of the ratios:

While L denotes the distance from the device 10 to determine the position immediately prior to the rolling stand 1. Similarly, during rolling of the strip 2, while lane 2 is loaded with tension, is determined by the shear VZ' strip between the stands, and on the basis of the shift VZ' strip between the stands in correlation with the slope of the SA' strip on the output side and shift V' strip 2 when directly preceding rolling stand 1, is determined by the corresponding curvature To' strip on the output side. This method is schematically represented in Fig.6, where respectively presents the steps S4 and S12 in Fig 3.

At step S13 is an alternative or in addition to the determination at step S6 - consider what Ino each of the rolling stands 1 to determine the appropriate control action S. At step S14 is then appropriate management of the respective rolling stand 1 and/or rolling stand 1, which is located directly after the respective rolling stand 1.

Determine the appropriate control action S is part of step S13 using the corresponding shift V' band, the corresponding slope SA' strip on the output side, and a corresponding shift VZ' strip between the stands. Appropriate control action S in phase S13 is also defined, with appropriate curvature To the head part of the strip on the output side, the corresponding slope SA parent part of the strip on the output side and the corresponding shift of the V head end of the strip, and applying the appropriate shift V' band, the corresponding slope SA' strip on the output side, and a corresponding shift VZ' strip between the stands. Is equivalent to applying the appropriate shift VZ' strip between the stands is the application of appropriate curvature To' strip on the output side, because both these quantities can easily convert one into another.

In particular, it is possible, on the basis of relevant parameters V, SA, To the head part of the strip to determine the initial line of the strip, on the basis of relevant parameters V', SA',' strip to define the th line current strip, and the difference between these two lines be interpreted as a state of tension in the band 2. This knowledge under stage S13 is used to ensure that the appropriate control action S be defined so that the appropriate control action S counteracts the deviation of the base 11 of the strip at the exit of the base strip 11 from the respective rolling stand 1.

For example, as shown in Fig.7, the respective rolling stand 1 and/or the rolling stand 1, which is located directly after the respective rolling stand 1, is controlled according to a particular respective governing influence of S at some point in time at which it is a member of the respective rolling stand 1 lane 2 (yet) applied tension. Alternatively, it is possible, as shown in Fig, the respective rolling stand 1 and/or rolling stand 1, which is located directly after the respective rolling stand 1, to operate according to a particular respective governing influence of S at some point in time at which a part of the respective rolling stand 1 band 2 is free from the applied tension.

In both cases, i.e. as in an embodiment in Fig.7, and in an embodiment according Fig corresponding control action S should, the mind is raised, to be determined by the managing device 3. The preferred way appropriate control action S is defined just before. However, alternatively it is also possible to determine the appropriate control action S intervals before running the respective rolling stand 1 and/or rolling stand 1, which is located directly after the respective rolling stand 1.

The above was explained the way in which the curvature To the head part of the strip on the output side or curvature To' strip on the output side is determined once and within the area of the rolling mill (thus, between each two immediately adjacent rolling stands 1) is taken as constant. However, there is other way of the action.

For example, it may be provided on each section rolling mill two or more devices 10 position. Placement of the device 10 to determine the position in this case is optimal if the device 10 to determine the position of evenly spaced relative to each other. For example, in the middle between each two immediately adjacent rolling stands 1 can accommodate, respectively, the device 10 to determine the position of the other device 10, the positioning can RA is to mestisa directly in front of the rolling stand 1, located directly after the respective rolling stand 1. In practice, however, for higher reasons, it may be necessary to deviate from this optimum in the sense of the accuracy of the measurement location.

If two or more devices 10 positioning are provided on the plot rolling mill, it is possible curvilinear course of the strip 2 between the corresponding two directly adjacent rolling stands 1 to approximate not only by a polynomial of the second degree (i.e. with constant curvature K or K'), but also by means of a polynomial, for example, third degree (i.e., when observed in the direction of the strip, with linearly varying curvature K or K').

Regardless of whether the curvature K and K' between the corresponding two directly adjacent rolling stands 1 constant or a function of the location x in the direction of the pass band, are applicable, in particular, the well-known theory of the Bernoulli-Euler bending beams that based on the local values of the curvature K and K' to obtain conclusions about the difference Δσ tensile stress from the edge 12 of the strip to the edge 12 of the strip. Then for the difference Δσ tensile stress the relation is valid:

where b is the width, h is the thickness of the strip. M corresponds to the local bending moment. Local bending moments, for its part, is connected with the values of the curvature K and K' value:

This E - modulus strips 2 when the current temperature of the strip, I - axial static moment of the cross-section of the strip in the direction of thickness of the strip. Axial static moment of the I-section is determined by the ratio of:

Fig.9 shows the possibility of determining the curvature K, K' on the output side, without requiring the device 10 to determine the position in figure 5. According to Fig.9, in the framework of the control device 3 is implemented physico-mathematical model 13. On physical-mathematical model of 13, according to figure 10, in step S21, for each rolling mill stand 1 is a corresponding shift of the V band and the corresponding tilt SA parent part of the strip on the output side. In addition, the physical-mathematical model 13 at step S21 served actual parameters for strip 2, a member of the respective rolling stand 1 and the strip 2 extending from the respective rolling stand 1. Finally, at the physical-mathematical model 13 at step S21 serves variables and parameters for the respective rolling stand 1. By means of physico-mathematical model 13 then at step S22 is determined by the corresponding curvature K, K' on the output side.

Physico-mathematical model 13 is based, on the one hand, the source and the position the curvature To the output side of the strip 2 for each of the rolling stands 1 obeys the relation:

ΔvA denotes here the difference in the velocities with which the edge 12 of the strip emerging from the respective rolling stand 1.

Same goes for other Δ-values. For example, vE is the speed at which the middle of the strip 2 is in appropriate considering rolling mill 1, ΔvE is the difference in the velocities with which the edge 12 of the strip are considered appropriate rolling mill 1.

In addition, true - when considering both locally width b of the strip, and globally - the continuity equation:

while hA and hE, and the respective rolling stands 1, denote the thickness of the strip on the output side and, respectively, on the input side.

Expressing relative velocity vA on the output side, from equation (9) should be linearized equation for the transverse difference of velocities relative to the middle of the strip width b of the strip:

The parameters on the input side (i.e. parameters with the final letter "E") with no known exceptions, namely for the first passable rolling stands 1 is known a priori, for other rolling stands 1 through the corresponding calculations based on the physico-mA is tematicheskoe model 13. (Average) width hA of the strip on the output side on the basis of known compression - known. The difference ΔhA strip thickness on the output side is obtained by equating the two relations

and

to obtain:

In equations (11)-(13) FW - load, s - zone deformation, cG - stand rigidity, kF - deformation resistance, T is the temperature of the strip 2, µ - coefficient of friction in the zone of deformation and y - eccentricity (corresponds to the shift of the V head band), with which the strip 2 passes appropriate considering rolling mill 1.

The relevant input parameters of physico-mathematical model of 13 must be known to the control device 3. In practice, it is usually the case, so the difference ΔhA height on the output side can be specified.

Described above in connection with figure 9 the way of the action is very fast. In particular, the curvature To the head part of the strip on the output side almost immediately available. So fundamentally it is possible to react quickly. In particular, it is possible, as fundamentally already mentioned and figure 10 again shows that the appropriate control action S to determine immediately after the definition of the corresponding curvature is To the head part of the strip on the output side and to control the respective rolling stand 1 immediately after the definition of the corresponding control action S under certain appropriate Manager the impact of S. In this case, often followed by reaction of the respective rolling stand 1, before the head part 8 bands will be included in the immediately following rolling mill 1. In principle, however, it would be possible to delay the running of the respective rolling stand 1, while the head portion 8 of the strip will not enter directly in the subsequent rolling stand 1.

In a method, according to figure 10, the strip 2 has a constant on sites curvature To the head part of the band. The length of individual sections, in which the band 2 is constant on sites curvature To the head part of the band, as a rule, considerably less than the distance G between the rolling stands 1. Therefore, the definition of shift V" head band as a function of the position of the strip 2 in the rolling mill is no longer as simple as described above. However, it is still possible, as separate sections continuously adjacent to each other.

The way action figures 9 and 10 can be performed separately, i.e. not providing device 10 determining the position between the rolling stands 1. However, the preferred way way action figures 9 and 10, under 11, is performed in conjunction with the device 10 to determine the position. In this case it is possible, according pig, in addition to the steps S21 and S22 in figure 10:

additionally at step S26 through with the appropriate device 10 determining the position to determine the appropriate shift VZ strip between the stands and

then at step S27 to correct identified on the basis of physico-mathematical model 13 curvature To the head part of the strip on the output side based on the particular shift VZ strip between the stands, the corresponding shift of the V head of the strip and the corresponding slope SA parent part of the strip on the output side.

Typically, the phase S27 corresponding curvature To the head part of the strip on the output side, according to the last-mentioned parameters (shift V head bands, tilt SA parent part of the strip on the exit side of the shift and the VZ strip between stands), is calculated again. Again the calculated curvature To the head part of the strip on the output side, then replaces the curvature To the head part of the strip on the output side, some on the basis of physico-mathematical model 13. Alternatively, it is possible, at least a substantial approximation, for example, at 70, 75 or 80%.

In addition to the step S27, may also be a step S28. At step S28 physico-mathematical model 13 is adapted based on the deviation of the curvature To the head part of the strip on the output side, determined on the basis of physico-mathematical model 13, from adjusted corresponding curvature To the head part of the strip on the output side. Physico-mathematical model 13 as such is consistent, thus the actual conditions, so for bands 2, rolled to a later point in time, is the best definition of curvature To the head part of the strip on the output side by means of physico-mathematical model 13.

As already mentioned, the application of physico-mathematical model 13 it is possible to quickly determine the appropriate control action S and very quickly to control the respective rolling stand 1 according to the respective governing exposure to S. Therefore, in the framework of action under 11 and 12 is required, taking into account the relevant control actions S, defined on the basis of physico-mathematical model 13, and is caused thereby changes the corresponding curvature To the head part of the strip on the output side, to determine the effective (mean) curvature KM warhead lanes 2 and the effective average curvature KM warhead lanes 2 to use for comparison in the step S27 or adaptation step S28. For example, you may cyclically on the basis of physico-mathematical models 13 to determine the appropriate curvature To the head part of the strip and then - for example, by the ratio

to determine the effective average curvature KM head band. In the above equation (14) i denotes the corresponding scan cycle, α is a suitable definition is i.i.d. weighting factor, which ranges from zero to one. The weighting factor α may be a constant time or a variable time. If it is variable in time, it is preferably reduced in time.

The present invention has many advantages. In particular, it works reliably and can be implemented by simple means, even through the retrofit of existing rolling mills.

The above description serves only the explanation of the proposed invention. The scope of protection of the proposed invention is determined solely by the applied claims.

1. Method of rolling strip rolling mill, containing several rolling stands (1), through which consistently pass band (2), including the input strip (2) with respect to the middle line (7) rolling in each of the rolling stands (1) with known corresponding shift (V) head of the strip and with the known corresponding slope (SE) of the head part of the strip on the input side, so that the head part (8) of the strip (2) from the respective rolling stand (1) exits with an appropriate shift (V) head of the band corresponding slope (SA) of the head part of the strip on the output side and the corresponding curvature (K) of the head portion of the strip on the output side, and the corresponding slope (SA) of the head h and the strip on the output side is determined on the basis of the corresponding slope (SE) of the head part of the strip on the input side and the corresponding compression, carried out in the respective rolling stand (1), and by an appropriate device (10) determine the position located between the respective rolling stand (1) and the rolling stand (1)immediately after the respective rolling stand (1)determine the appropriate shift (VZ) of the head part (8) of the strip between the rolling stands, the corresponding curvature (K) of the head part of the strip (2) on the output side is determined on the basis of relevant specific shift (VZ) of the head part of the strip between the rolling stands, the corresponding shift (V) head of the strip and the corresponding tilt (SA) of the head part of the strip on the output side, while on the basis of appropriate curvature (K) of the head portion of the strip on the exit side of determine the appropriate control action (S) for the respective rolling stand (1) and/or rolling stands (1)immediately after the respective rolling stand (1) and is governed under a specific corresponding control impact (S) of the respective rolling stand (1) and/or rolling stand (1)immediately after the respective rolling stand (1).

2. The method according to claim 1, characterized in that a corresponding shift (V) head of the band corresponding to the slope (SA) of the head part of the strip on the exit side of the corresponding curvature (K) of the head portion of the strip on the exit side of remember after entering the strip (2) in the last rolling stand (1) mill lane (2), located between the rolling stands (1), load tension bar (2) with respect to the middle line (7) rolling in each of the rolling stands (1) injected with known corresponding shift (V) bands and known corresponding slope (SE') strip from the entrance and from the respective rolling stand (1) output from the corresponding shift (V) band, corresponding slope (SA') of the strip on the output side and the corresponding curvature (K') of the strip on the output side, the corresponding slope (SA') of the strip on the output side is determined on the basis of the corresponding slope (SE') strip on the input side and implemented in the respective rolling stand (1) compression, using a device (10) determine the position, placed directly behind the respective rolling stand (1)determine the appropriate shift (VZ') strip (2) between the rolling stands, based on the corresponding shift (V) band, corresponding slope (SA') of the strip on the output side, and the corresponding shift (VZ') strip between the rolling stands determine the appropriate curvature (K') of the strip on the output side, while the corresponding control action (S) determined on the basis of the corresponding shift (V') of the strip, the corresponding slope (SA') gender the child on the output side and the corresponding shift (VZ') strip between the rolling stands.

3. The method according to claim 2, characterized in that the appropriate control action (S) is determined in such a way that it counteracts the deviation at the exit of the strip (2) from the respective rolling stand (1).

4. The method according to any of claim 2 or 3, characterized in that the respective rolling stand (1) and/or rolling stand (1)immediately after the respective rolling stand (1), is governed under a specific corresponding control impact (S), to a point in time to which the strip (2)included in the respective rolling stand (1), loaded with tension.

5. The method according to any of claim 2 or 3, characterized in that the respective rolling stand (1) or rolling stand (1)immediately after the respective rolling stand (1), is governed under a specific corresponding control impact (S), to a point in time to which the strip (2)included in the respective rolling stand (1), free from tension.

6. The method according to any one of claims 1, 2 or 3, characterized in that on the basis of the corresponding shift (V) head of the band corresponding slope (SA) of the head part of the strip on the output side and the corresponding curvature (K) of the head portion of the strip on the exit side of the respective rolling stand (1) determine the appropriate shift (V) head of the strip is the corresponding slope (SE) head of the track from the entrance to the rolling stand (1), immediately after the respective rolling stand (1).

7. The method according to any one of claims 1, 2 or 3, characterized in that the rolling stand (1)immediately after the respective rolling stand (1), manage the latest at the input strip (2) in the rolling stand (1), directly following the respective rolling stand (1), according to certain appropriate control action (S).

8. The method according to any one of claims 1, 2 or 3, characterized in that the curvature (K) of the head portion of the strip on the exit side of standing on its sites.

9. The method according to any one of claims 1, 2 or 3, characterized in that the curvature (K) of the head part of the band from the output varies with the distance (x) from the respective rolling stand.

10. Method of rolling strip rolling mill, containing several rolling stands (1), through which consistently pass band (2), including the input strip (2) with respect to the middle line (7) rolling in each of the rolling stands (1) with known corresponding shift (V) head of the strip and with the known corresponding slope (SE) of the head part of the strip on the input side, so that the head part (8) of the strip (2) from the respective rolling stand (1) exits with an appropriate shift (V) head of the band corresponding slope (SA) g is lowney part of the strip on the output side and the corresponding curvature (K) of the head portion of the strip on the output side, moreover, the corresponding slope (SA) of the head part on the output side is determined on the basis of the corresponding slope (SE) of the head part of the strip on the input side and the corresponding compression implemented in the respective rolling stand (1), specify in the physical-mathematical model (13) the values of the corresponding shift (V) head of the strip and the corresponding slope (SA) of the head part of the strip on the output side, the actual parameters of the strip (2), a member of the respective rolling stand (1)and strip (2)extending from the respective rolling stand (1), as well as the variables and parameters of the respective rolling stand (1), and determine the corresponding curvature (K) of the head portion of the strip on the output side by means of physico-mathematical model (13), and on the basis of appropriate curvature (K) of the head portion of the strip on the exit side of determine the appropriate control action (S) for the respective rolling stand (1) and/or rolling stands (1)immediately after the respective rolling stand (1), with the respective rolling stand (1) and/or rolling stand (1)immediately following for the respective rolling stand (1), is governed under a specific corresponding control impact (S).

11. The method according to claim 10, characterized in that after determining relevant to the ith curvature (K) of the head portion of the strip on the output side by means of physico-mathematical model (13), additionally by an appropriate device (10) determine the position located between the respective rolling stand (1) and the rolling stand (1)immediately after the respective rolling stand (1)determine the appropriate shift (VZ) of the head part of the strip (2) between the rolling stands, and the corresponding curvature (K) of the head portion of the strip on the exit side of adjusted based on the particular shift (VZ) of the head part of the strip between the rolling stands, the corresponding shift (V) head of the strip and the corresponding slope (SA) of the head part of the strip on the output side.

12. The method according to claim 11, wherein the physical-mathematical model (13) is adapted on the basis of deviations defined by physico-mathematical model (13) the corresponding curvature (K) of the head portion of the strip on the output side of the adjusted corresponding curvature (K) of the head portion of the strip on the output side.

13. The method according to any of p, 11 or 12, characterized in that the appropriate control action (S) determined immediately after the definition of the appropriate curvature (K) of the head portion of the strip on the output side, and the respective rolling stand (1) is administered immediately after the definition of the corresponding control action (S) the agreement is but specific to the respective governing impact (S).

14. The method according to any of p, 11 or 12, characterized in that the rolling stand (1)immediately after the respective rolling stand (1), manage the latest at the input strip (2) in the rolling stand (1), directly following the respective rolling stand (1), according to certain appropriate control action (S).

15. The method according to any of p, 11 or 12, characterized in that the curvature (K) of the head portion of the strip on the exit side of standing on its sites.

16. The method according to any of p, 11 or 12, characterized in that the curvature (K) of the head part of the band from the output varies with the distance (x) from the respective rolling stand (1).

17. The media data with the stored computer program (4)with native code (5), directly executable by the appliance (3) mnogoluchevogo rolling mill for rolling strip in accordance with the method according to any one of claims 1 to 16.

18. Control device mnogoluchevogo rolling mill, made and programmed for execution control rolling strip in accordance with the method according to any one of claims 1 to 16.

19. Control device for p, characterized in that it has software for execution control rolling of the strip.

20. Rolling mill, enabling the th several rolling stands (1), through which pass through the strip (2), but he has a control device (3) according to any one of p or 19, is arranged to control a rolling mill during rolling of the strip in accordance with the method according to any one of claims 1 to 16.



 

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