The Necessity of the Tolerance Detection of the Annealing Furnace Roll of the Cold Rolling Mill
With the continuous production of the cold rolling production line of the steel plant, the roll on the rolling mill of the whole production line will continuously accumulate deformation and loss under the action of high pressure, corrosion, wear, etc. When the deformation and loss accumulate to a certain extent, it will have a greater impact on the quality of the product line and increase the rate of defective products. Therefore, for such reasons, the annealing furnace roll of rolling mill needs regular
Maintenance and adjustment.
Application of
Laser Tracker in roll detection
API Radian laser tracker can be used for large range (up to 160 meters) and high accuracy( μ m. Micron level) measurement characteristics, establish the overall coordinate system, and compare the actual measurement data of each roll for adjustment and verification.
During measurement, the operator holds the target ball (SMR) with built-in prism to touch the position to be measured, and Radian will shoot a laser to lock and track the center position of the target ball, and capture and collect data at the target position at an ultra-high data acquisition rate of 1000Hz; The collected data will be sent to the
Measurement Software in real time for comparison and analysis, guidance and adjustment, so as to achieve the purpose of detection.
Example of cold rolling annealing furnace roll inspection
Description: annealing furnace rolls of a cold rolling production line of a steel plant are distributed on+5m platform and 23m platform; The central point of the production rolling line is arranged at an elevation of 0 m above the equipment ground and is not visible; Each layer of platform is evenly distributed with about 18~30 furnace rollers, and the furnace rollers are only exposed at the end, and the body is covered by thermal insulation layer, so it is impossible to measure the entire surface of the furnace rollers.
Test demand and purpose: It is required to measure and provide the perpendicularity of the furnace roll and the ground rolling center line, the levelness of the ground level, and provide the adjustment direction data and adjustment plan. After adjustment, the main problem of strip steel deviation should be solved.
Measurement scheme
1. Establishment of survey overall coordinate system
Since the furnace roll is distributed on the+5m platform and the 23m platform, the central point of the production rolling line is controlled at the elevation of 0 m above the equipment ground and is not visible, first establish the overall coordinate system of measurement with the elevation of 0 m as the reference point:
1.1 First, clean the 0 m elevation point (as shown in Figure 3, left);
1.2. Using the stable frame around the measured roll and other conditions, lay out the coordinate system to locate the measuring points (the points can be arranged as far as possible
Measure more so that the equipment can be transferred when measuring in different areas, as shown in Figure 3, right);
1.3 Select the measuring position of the tracker, use the high-precision electronic level in the instrument to adjust the instrument level. After leveling, use the positioning point measuring base (as shown in Figure 4) to measure the coordinates of each 0 m elevation point (note: after the first 0 m elevation point is measured, the next elevation point is not intervisibility, so it is necessary to use the previously set station reference point for post-station measurement). After the measurement, The horizontal datum coordinate system based on the 0 m elevation point can be established to obtain the 0 m elevation vertical plane XZ and horizontal datum plane XY (as shown in Figure 5).
2. Measurement of furnace roll system axis on 5m platform and 23m platform
Since the furnace roll only exposes its end and its body is covered by insulating layer, the whole surface of the furnace roll cannot be measured, so special tooling can be used to coordinate the measurement of the furnace roll.
2.1 First, open the end cover of the furnace roll and clean it (as shown in Figure 6);
2.2. Select the end face side of the visible furnace roll on the platform and set up the tracker at the stable position (as shown in the main figure of Figure 7). Multiple measurement positions can be set up by using the transfer station to ensure that each furnace roll is measured. When setting up the tracker, if the space is too narrow, you can also choose to use the magnetic suction seat to adsorb the tracker on the steel surface such as the furnace roll frame (as shown in the upper left of Figure 7 and the lower left of Figure 7);
2.3. When measuring the roll axis, since each roll needs to measure at least two rotation circles around the axis to obtain the axis data, special tooling (as shown in Figure 8) is selected to cooperate with the operation: the tooling is adsorbed on the end face of the roll, and the roll drives the tooling to rotate around the axis, so that the new rotation circle can be measured; By adjusting the position of the swing rod of the tooling, several different rotation circles can be measured;
2.4. The result point set after the target ball is collected (as shown in Figure 9), the center of each circle segment is obtained by using the function of fitting the center of the circle of the software, so as to obtain the axis of rotation, that is, the axis of the furnace roll.
3. Analysis of perpendicularity between furnace roll axis of each layer and ground rolling center line and levelness of geoid
When the axes of each furnace roll on the two layers are measured, they can be fitted from the software to obtain the verticality of each furnace roll axis and the previously determined 0 m base point rolling center plane, and the levelness of each furnace roll axis and the geodetic plane (as shown in Figure 10), and the error size and direction can be displayed, thus providing reliable and intuitive guidance for the next step of furnace roll adjustment.
4. Guide the adjustment of furnace roll plan
After obtaining the measurement data in the above 3, we can know the adjustment amount and direction of the furnace roll that needs to be adjusted, so that the furnace roll can be adjusted under the guidance of the tracker. After the adjustment is completed, the adjusted roll can be retested, and its vertical and parallel conditions with the whole roll system can be analyzed, so that the whole roll system is not twisted, and then the problem of strip steel deviation can be solved.
overview
The measurement and detection of steel mill rolls often has the characteristics of large measurement span, large elevation difference, high demand accuracy, and due to the limitations of environmental factors, there will also be problems such as non-visibility of measurement points, narrow measurement space, etc. The Radian series laser tracker of API brand has the excellent ability of large-scale precision measurement, and is convenient to use. It can solve the problem of narrow measurement space with flexible installation methods, supplemented by various accessories and tooling with a full range of functions, which is the best choice to meet the measurement and inspection needs of steel mills.
