Determination method for determination of the rolling or guiding gaps of the roll stands or guide stands in a multi-stand rolling mill
In order to be able to determine the rolling or guiding gaps of the roll stands or guide stands in a multi-stand rolling mill, at a predetermined measurement precision, with the least possible effort, a master calibration and intermediate calibrations are carried out, wherein various calibration measures are refrained from, in a targeted manner. The targeted lack of recourse in the case of specific calibrations is also independently advantageous.
1 . A determination method comprising:
providing a multi-stand rolling mill comprising roll stands having a rolling gap or guide stands having a guiding gap, a pass line that reaches through the roll stands or guide stands that serves as a reference for a gap offset, an input side, and an output side;
arranging a camera at one of the input side and the output side, and arranging a background illumination on another one of the input side and the output side; and
subsequently determining the rolling gap or the guiding gap of the stands using an information technology device, by,
in a first step, calibrating the camera and the information technology device offline or inline, with reference to the rolling mill, and
in a second step, determining the rolling gap or the guiding gap inline, using the camera and the information technology device,
wherein for the calibration in the first step, first a master calibration is carried out, then the camera and the background illumination are removed, and afterward a rolling process is carried out, and afterward the camera and the background illumination are arranged on one of the input or output sides again, for an intermediate calibration, and calibrated in the first step, before, in the second step, the camera, making use of the information technology device, determines the rolling or guiding gaps inline once again,
wherein during the master calibration, at least two reference scales that are oriented in a linearly independent manner are measured for a reference sensor to be used for intermediate calibrations, and a pixel factor determined from the reference scales is stored in memory in the information technology device, and
wherein in the information technology device, the roll stands or guide stands are successively designated based on position along the pass line, and the information technology device stores a measurement direction input option based on placement of the camera at the one of the input side and the output side and of the background illumination at the other of the input side and the output side and a measurement direction is input, and the information technology device assigns potential measurement results to each of the roll stands or guide stands independently of the measurement direction.
2 . The determination method according to claim 1 , wherein a first reference sensor and a second reference sensor are arranged in the pass line and at least one of the first reference sensor and the second reference sensor is a roll of the roll stands, a guide of the guide stands, a roll stand of the roll stands, a guide stand of of the guide stands, a reference stand, or a calibration ring.
3 . The determination method according to claim 2 , wherein the first reference sensor comprises a first calibration ring which serves as a first master reference and the second reference sensor comprises a second calibration ring which serves as a second master reference.
4 . The determination method according to claim 3 , wherein the first calibration ring comprises at least two reference arms and the second calibration ring comprises at least two reference arms.
5 . The determination method according to claim 1 , wherein in the information technology device, the roll stands or guide stands are designated successively as a function of a rolling direction or wherein a measurement image is mirrored.
6 . The determination method according to claim 1 ,
wherein the calibration of the camera and of the information technology device takes place in the first step, using at least one reference sensor close to the camera and at least one reference sensor away from the camera, wherein each of the at least one reference sensor close to the camera and the at least one reference sensor away from the camera is not arranged between the rolls or guides of a first of the stands and the rolls or guides of a last of the stands.
7 . The determination method according to claim 1 , wherein in the first step, the camera and the information technology device are calibrated offline or inline, with reference to the rolling mill using at least one reference sensor close to the camera and at least one reference sensor away from the camera, wherein each of the at least one reference sensor close to the camera and at least one reference sensor away from the camera is not arranged between the rolls or guides of the first of the stands and the rolls or guides of the last of the stands,
wherein in the second step, the camera determines the rolling or guiding gaps inline, making use of the information technology device, wherein
(i) before the calibration that corresponds to the first step, first the camera is arranged on a reference holder in a previously defined reference position, and the reference sensor close to the camera and the reference sensor away from the camera are arranged in previously defined reference positions, and then, for the calibration corresponding to the first step, the reference sensor close to the camera and the reference sensor away from the camera are measured using the camera and the information technology device, and subsequently, the pass line or the offset from the pass line or a pixel factor are determined from the measurement result; or
(ii) the reference sensor close to the camera and the reference sensor away from the camera are coordinated with one another and with reference to the camera to enable simultaneous detection by the camera of the reference sensor close to the camera and the reference sensor away from the camera; or
(iii) before the calibration that corresponds to the first step, the camera is arranged on a reference holder, in a previously defined reference position, and subsequently a lens of the camera is displaced, in terms of focus, until the reference sensor close to the camera and the reference sensor away from the camera are imaged with a matching lack of focus.
8 . The determination method according to claim 7 , wherein the reference sensor close to the camera or the reference sensor away from the camera is a roll of the roll stands, a guide of the guide stands, or a reference stand.
9 . The determination method according to claim 8 , wherein the reference sensor close to the camera, the reference sensor away from the camera or the reference stand are brought into a reference position.
10 . The determination method according to claim 8 , wherein the rolls or guides or correspondingly moved modules of a first and a last of the roll stands are brought into a reference position and are used as a reference close to the camera or a reference away from the camera.
11 . The determination method according to claim 7 , wherein before the calibration that corresponds to the first step, the camera is arranged on a reference holder, in a previously defined reference position, and subsequently a lens of the camera is displaced, in terms of focus, until the reference sensor close to the camera and the reference sensor away from the camera are imaged with a matching lack of focus, and
wherein the lens has a fixed focal width or wherein different lenses ( 48 ) are used for different gap sets.
12 . The determination method according to claim 7 ,
wherein before the calibration that corresponds to the first step, a target is arranged on a reference holder in a previously defined reference position or
wherein a target is coordinated, in terms of target size of the target, with the reference sensor close to the camera and the reference sensor away from the camera, to enable the camera to detect the target, together with the reference sensor close to the camera and the reference sensor away from the camera, at the same time.
13 . The determination method according to claim 1 , wherein the rolling gap or the guiding gap is determined immediately after a rolling process.
14 . The determination method according to claim 1 , wherein the rolling gap or the guiding gap is measured in a warm state of the roll stand or of the guide stand.
15 . The determination method according to claim 1 , wherein a first reference sensor and a second reference sensor are used for intermediate calibrations, wherein for the master calibration, reference positions for the camera and the target together with the background illumination, with reference to the pass line, are established, the position of the pass line with reference to the camera and the target together with the background illumination is stored in memory in the information technology device ( 60 ), and at least a first reference scale of the first reference sensor, a second reference scale of the second reference sensor, and first and second pixel factors determined from the first and second reference scales are stored in memory in the information technology device.
16 . The determination method according to claim 1 , wherein for measuring a first reference scale of the at least two reference scales, a first scale is set at a first reference height previously defined with reference to the pass line, and measured by the camera, making use of an information technology device, and for measuring a second reference scale of the at least two reference scales, a second scale is set at a second reference height previously defined with reference to the pass line, and measured by the camera, making use of the information technology device, wherein the measurement result is stored in memory in the information technology device as a pixel factor.
17 . The determination method according to claim 1 , wherein only two reference sensors are used for the intermediate calibration.
18 . The determination method according to claim 1 , further comprising recording at least one of three reference scales, and removing more than two of the stands for the master calibration.
19 . The determination method according to claim 1 , wherein for establishing the reference positions of the camera and of the target with reference to the pass line, master references are installed in related reference positions, wherein the master references are detectable by the camera and the information technology device.
20 . The determination method according to claim 1 , wherein for establishing the reference positions of the camera or the target with reference to the pass line, the position of the camera or of the target is varied or wherein the detected position of the master references is stored in memory in the information technology device as a position of the pass line.
21 . The determination method according to claim 1 , wherein the camera records multiple images during a measurement and compares them with one another.
22 . The determination method according to claim 1 , wherein filters used for the camera are changed during the measurement.
23 . The determination method according to claim 1 , wherein in the second step, only a gap form of the rolling gap or the guiding gap is determined as the rolling gap or the guiding gap is determined.
24 . The determination method according to claim 1 , wherein the rolling mill comprises at least two rolling machines and in the second step, only the gap offset relative to the pass line that reaches through the at least two rolling machines is determined as the rolling gap or the guiding gap.
25 . The determination method according to claim 1 , wherein a first reference sensor and a second reference sensor are arranged in the pass line, and in the first step, a position of the camera or of a target are changed to enable the camera to detect separately the first and second reference sensors or the target.
26 . The determination method according to claim 1 , wherein for the master calibration, master references are installed on the pass line, and the camera, and the background illumination and a target are oriented with reference to the pass line defined using the master references or the position of the pass line is measured accordingly, with reference to the camera or the target, and stored in memory in the information technology device, while for the intermediate calibration, no use of the master references is made.
27 . The determination method according to claim 1 , wherein for the master calibration, at least three reference scales are recorded offline, at reference heights previously defined with reference to the pass line, or inline in the case of at least one stand removed from the rolling mill, and a pixel factor determined from the reference scales is stored in memory in the information technology device.
28 . The determination method according to claim 1 , wherein first and second references are used for intermediate calibrations, wherein for the master calibration, reference positions for the camera and a target are established with reference to the pass line, the position of the pass line with reference to the camera and the target is stored in memory in the information technology device, and at least a first reference scale of the first reference and a second reference scale of the second reference are measured, and a pixel factor determined from the reference scales is stored in memory in the information technology device.
29 . The determination method according to claim 1 , wherein the intermediate calibration is used as a calibration in the first step of the determination method.
30 . A determination method comprising:
providing a multi-stand rolling mill comprising roll stands having a rolling gap or guide stands having a guiding gap, a pass line that reaches through the roll stands or guide stands that serves as a reference for a gap offset, an input side, and an output side;
arranging a camera at one of the input side and the output side, and arranging a background illumination on an other one of the input side and the output side; and
subsequently determining the rolling gap or the guiding gap of the stands using an information technology device, by,
in a first step, calibrating the camera and the information technology device offline or inline, with reference to the rolling mill, and
in a second step, determining the rolling gap or the guiding gap inline, using the camera and the information technology device, wherein
(i) in the second step, only a gap form of the rolling gap or the guiding gap is determined as the rolling gap or the guiding gap is determined; or
(ii) the rolling mill comprises at least two rolling machines and in the second step, only the gap offset relative to the pass line that reaches through the at least two rolling machines is determined as the rolling gap or the guiding gap; or
(iii) in the information technology device, the roll stands or guide stands are successively designated based on position along the pass line, and the information technology device stores a measurement direction input option based on placement of the camera at the one of the input side and the output side and of the background illumination at the other of the input side and the output side and a measurement direction is input, and the information technology device assigns potential measurement results to each of the roll stands or guide stands independently of the measurement direction; or
(iv) a first reference sensor and a second reference sensor are arranged in the pass line and in the first step, a position of the camera or of a target are changed to enable the camera to detect separately the first and second reference sensors or the target,
wherein for the calibration in the first step, first a master calibration is carried out, then the camera and the background illumination are removed, and afterward a rolling process is carried out, and afterward the camera and the background illumination are arranged on one of the input or output sides again, for an intermediate calibration, and calibrated in the first step, before, in the second step, the camera, making use of the information technology device, determines the rolling or guiding gaps inline once again,
wherein during the master calibration, at least two reference scales that are oriented in a linearly independent manner are measured for a reference sensor to be used for intermediate calibrations, and a pixel factor determined from the reference scales is stored in memory in the information technology device.
31 . The determination method according to claim 30 , wherein during the master calibration, at least one reference offset of a reference sensor to be used for intermediate calibrations is measured and stored in memory in the information technology device.