The method for determining the flatness of a moving strip of material

 

(57) Abstract:

The method for determining the flatness of a moving strip of material relates to the fields of metallurgy, production of materials and can be used mainly in rolling technology. The method for determining the flatness of a moving strip of material based on the measurement of the angle formed by the lines of intersection of a plane tangent to the surface of the strip in the measuring point, and a plane tangent to the support elements, which moves the strip, with the plane passing through the measurement point and located along the direction of movement of the strip perpendicular to the plane tangent to the support elements, which moves the strip, and relative elongation of the tape longitudinal sections of the bands allocated to the measuring device, is calculated from the condition:

< / BR>
< / BR>
where the lengthening of the m-th tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the strip (m= 1, 2, 3, ...);

N is the number of dimensions involved in the averaging;

m,iis the desired angle (in radians) for m-g the BR>m,i+1is the desired angle (in radians) for m-th tape longitudinal stretch bands allocated to the measuring device, in the i + 1-th measurement;

mthe relative lengthening of the m-th tape longitudinal stretch bands allocated to the measuring device;

lengthening the shortest tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the strip.

The invention improves the accuracy of the measurement, including high vibration environments. 2 Il.

The invention relates to the fields of metallurgy, production of materials and can be used mainly in the plate technologies.

One of the accepted parameters characterizing the flatness of the strip of material is transverse (across the strip width) distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device.

A known method for determining the flatness of a moving strip of material, based on the measurement of transverse distribution of the relative movements of the tape longitudinal ocagini in these areas using a variety of contact sensors (application Japan N 56-51563, CL IPC G 01 B 7/34, G 01 L 5/10, G 01 B 7/00, publ. 1981; Japan's bid N 54-10872, CL IPC G 01 B 7/34, publ. 1979). For tensile stresses can be calculated relative elongation of the tape longitudinal sections of the bands allocated to the measuring device. The main disadvantage of this method is a contact measurement method that, in some cases, especially during hot rolling steel strip, encounters considerable technical difficulties.

Closest to the proposed invention is a method for determining the flatness of a moving strip of material given in the description of the measuring flatness for hot rolling (Flatness Gauge for Hot Strip Mills, Mitsubishi Electric, Japan, the prospect SEG 317-A / ROD, 1985). This method is based on measuring the transverse distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, in which, with a high repetition rate, a measure of the height of the surface of these areas with respect to a plane tangent to the supporting elements, which moves the strip, and the measurement of the speed of the strip, with the subsequent calculation of the lengths of tape longitudinal sections of the bands allocated to the measuring of mouth/BR>Lm- length m-th tape longitudinal stretch bands allocated to the measuring device (m=1,2,3...);

N is the number of dimensions involved in the averaging;

hm,i- the height of the strip surface relative to a plane tangent to the support elements, which moves the lane in the i-th dimension (i= 1,2,3...);

hm,i+1- the height of the strip surface relative to a plane tangent to the support elements, which moves the strip, i+1-th dimension (i= 1,2,3...);

Vi- the average speed of the strip in the time interval ti+1-ti;

ti- the time of the i-th measurement;

ti+1the moment i+1-th measurement;

m- - relative elongation of the m-th tape longitudinal stretch bands allocated to the measuring device (m=1,2,3...);

Lmin- the length of the shortest tape longitudinal stretch bands allocated to the measuring device.

In the above condition, the difference between the moments (i+1)-th and i-th measurement value is known and determined by the technical characteristics of the device. The speed of movement of the strip during the rolling process value is almost constant, however, the knowledge of it with good accuracy neophema device uses multiple laser light sources and television recorders (for each tape longitudinal section has its own pair), providing a height measurement using the method of optical triangulation. It is assumed that at time ti+1the height of the strip section, measured at time tithat has not changed.

However, when the movement of the strip on the roller experiencing vibration that contributes, because of non-fulfilment of the above assumptions, significant error in the measurement of height differences and, accordingly, the relative movements of the tape longitudinal sections of the bands allocated to the measuring device. To reduce the influence of this factor requires additional special measures, such as measuring the speed of vertical movement of the strip due to vibration or the use of filtering techniques that dramatically reduces the performance of the measuring system and reduces the effectiveness of its application. In addition, the necessity of measuring the speed of movement of the strip requires the use of appropriate devices and contributes to the error in the measurement error relative movements of the tape longitudinal sections of the strip.

The technical result of the proposed method is to improve the accuracy of measuring the relative movements of the tape longitudinal sections of the bands allocated to the result of the proposed method, based on the measurement of transverse distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, measure the angle formed by the lines of intersection of a plane tangent to the surface of the strip in the measuring point, and a plane tangent to the support elements, which moves the strip, with the plane passing through the measurement point and located along the direction of movement of the strip perpendicular to the plane tangent to the support elements, which moves the strip and relative elongation of the tape longitudinal sections of the bands allocated to the measuring device, is calculated from the condition:

< / BR>
< / BR>
where

the lengthening of the m-th tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the band, (m=1,2,3...);

N is the number of dimensions involved in the averaging;

m,iis the desired angle (in radians) for m-th tape longitudinal stretch bands allocated to the measuring device, the i-th dimension (i=1,2,3... );

m,i+1is the desired angle (in radians) for m-th tape lengthwise in the s m-th tape longitudinal section of the strip, emitted by the measuring device;

lengthening the shortest tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the strip.

In Fig. 1 shows a graphical illustration of the location of the desired angle, and Fig. 2 - geometry of the measurement of the desired angle for a single pair of emitter-detector, and accordingly, a separate tape longitudinal stretch bands allocated to the measuring device,

where

1 is the desired angle;

2 - plane tangent to the surface of the strip at the point of measurement;

3 - the surface of the moving strip of material;

4 - point measurement;

5 is a plane that is tangent to the supporting elements, which moves the strip;

6 is a plane passing through the measurement point and located along the direction of movement of the strip perpendicular to the plane tangent to the support elements, which moves the strip;

7 - the angle of the light beam of the laser emitter with respect to a plane tangent to the supporting elements, which moves the strip;

8 - an incident beam;

9 - Olney the supporting elements, which moves the strip;

12 is normal to the plane tangent to the surface of the strip at the point of measurement.

The method for determining the flatness of a moving strip of material, based on the measurement of transverse distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, consider one of the possible ways of measuring the desired angles.

Above the surface 3 (Fig. 1) moving strip of material at some angles to the plane 5, the tangent to the supporting elements, which moves the band have several laser emitters and the corresponding position-sensitive detectors.

Measurement of desired angles 1 is produced with a high repetition rate. The desired angle 1 is formed by the intersection line of the planes 2 and 5 with the plane 6.

From consideration of the geometry of the measurement (Fig. 2) that in the cross-section plane 6 desired angle 1 equals angle formed by the normal 11 to the plane 5, the tangent to the supporting elements, which moves the strip, and the normal 12 to the plane 2, the tangent to the surface of the strip in the measuring point 4, and associated with the angles 7 and 10 dependency:

< / BR>
where

m,iangle 10 between the incident and reflected beams;

the angle 7 of inclination of the light beam of the laser emitter with respect to a plane tangent to the supporting elements, which moves the strip.

Therefore, knowing the angle , and measuring the anglem,ibetween the incident and reflected rays 8 and 9, respectively, using a position-sensitive detector, it is possible to determine thereby, and the anglem,i. The next dimension in the same way determine the anglem,i+1, and so on. After collection of a sufficient number of measurements made with a high repetition rate, calculate the elongation of the m-th tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the strip, in accordance with the above condition:

< / BR>
From the totality of the measured movements of the tape longitudinal sections of the bands allocated to the measuring device relative to the specified area of the projections on the plane 5, the tangent to the support elements, which moves the strip, choose the lowest most appropriate corsicanna elongationmeach of the m specified sites of conditions:

< / BR>
receiving, thus, the transverse distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device. The transverse distribution of the relative movements of these plots, comparing, for example, their maximum and minimum values, judgments about the flatness of the strip.

With this method the vertical parallel displacement of the strip associated with vibration do not affect the measured parameter is the angle, which allows us to provide a more precise measurement of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, in comparison with the prototype.

In addition, there is no need to measure the speed of movement of the strip, because the speed is not included in the expression to calculate the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, and the transverse distribution of the relative movements is correlated with a time interval during which measurements were performed, because the result of the calculation is a quantitative characteristic of the process is esta strip, it is necessary that the speed of the strip was approximately constant and known. In this case, the correlation of measurement results with specific parts of the strip can be performed with sufficient accuracy.

The method for determining the flatness of a moving strip of material, based on the measurement of transverse distribution of the relative movements of the tape longitudinal sections of the bands allocated to the measuring device, wherein the measure of the angle formed by the lines of intersection of a plane tangent to the surface of the strip in the measuring point, and a plane tangent to the support elements, which moves the strip, with the plane passing through the measurement point and located along the direction of movement of the strip perpendicular to the plane tangent to the support elements, which moves the strip and relative elongation of the tape longitudinal sections of the bands allocated to the measuring device, is calculated from the condition:< / BR>
< / BR>
< / BR>
where the lengthening of the m-th tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the support elements on which paramedian) for m-th tape longitudinal section of the strip, allocated to the measuring device, the i-th dimension (i= 1, 2, 3 ...);

m,i+1is the desired angle (in radians) for m-th tape longitudinal stretch bands allocated to the measuring device, (i + 1)-th dimension;

mthe relative lengthening of the m-th tape longitudinal stretch bands allocated to the measuring device;

lengthening the shortest tape longitudinal stretch bands allocated to the measuring device relative to the projection of the specified area on the plane tangent to the supporting elements, which moves the strip.

 

Same patents:

The invention relates to detection of motion of the device relative to the surface to control the operation of this device when processing the surface

The invention relates to a pulse technique and can be used in devices certification of products of computer engineering such as control devices beating hard magnetic disks and their foundations

The invention relates to measuring technique and can be used to control the size of long cylindrical articles

The invention relates to measuring technique and can be used to control surface

The invention relates to a measurement technique, namely a method of registration of the topography of the sample surface scanning tunneling microscopes

The invention relates to measuring technique and can be used in instrument making and precision engineering to control the shapes of objects by optical methods

The invention relates to the field of radio physics and laser ranging and can be used to control the transverse and longitudinal profiles of railway structures, underground structures, different roads, pipelines, mines, mining, and also to build profiles of other structures and volumes

The invention relates to measuring equipment, namely, laser interferometry, and can be used to control the deviations of the form

The invention relates to the field of engineering, in particular to control the dimensions of the parts bearing on the operations of the working surface

The invention relates to techniques for measuring variations of the shape and radius of curvature of complex surfaces and, in particular, to devices for automatic measurement of the shape of the parabolic microwave antennas-range contactless method

The invention relates to measuring technique and can be used for contactless measurement of the profile of parts like rotation body and also weak waviness of the surface in the form of spatial functions

The invention relates to measurement devices, and in particular to methods of determining geometric parameters of objects and optical devices to implement these methods
Up!