Measurement Method Of Ladle Wall Thickness And Temperature Field Based On Laser Scanning And Positioning

At the site of the steel and metallurgy industry,from the beginning of converter tapping to the end of continuous casting,molten steel has been stored in the ladle.At this stage,heat transfer occurs between the ladle lining and the temperature field of the ladle affects the converter-continuous casting directly.For example,the temperature drops of tapping steel,the heating and cooling rate of molten steel at the refining station,the temperature change of molten steel in the tundish,etc.At the same time,the monitoring of the service life and safety performance of the ladle is particularly important in daily production.Since the ladle is a high-temperature moving object,traditional methods such as actual measurement and numerical simulation cannot measure the residual brick thickness of the ladle working layer accurately.The thickness of the residual bricks is usually manually checked,judged and controlled by experience.The on-line measurement of the working layer thickness of the ladle and the temperature field of the inner wall of the ladle can avoid the accident of ladle leakage effectively,reduce the labor and material costs,and ensure the safe and smooth operation of production.Therefore,it is practically significant to master the law of ladle wall thickness and temperature field change.According to the main influencing factors of the ladle condition at the steel-making site,this paper designed an online measurement scheme of ladle wall thickness and temperature field,selected appropriate sensors and designed related algorithms to realize the measurement of ladle wall thickness and temperature field.The main research contents are as follows:1.Measurement method of ladle wall thickness and temperature field based on laser scanning and positioningAiming at the difficult position of the turnover ladle at the measurement station and the related factors such as the on-site environment,this paper proposes a method for measuring the wall thickness and temperature field of the ladle based on laser scanning and positioning.The positioning laser is used to determine the location of the ladle to be measured.Then the three-dimensional rotating platform drives the main measurement laser and infrared temperature sensor to scan the inner wall surface of the ladle,which obtains the distance value and temperature value of each measured point on the inner wall of the ladle.2.Design of Calculation algorithm of ladle wall thickness and construction algorithm of temperature field and field measurementsAccording to the collected space position of the ladle,the distance and temperature of each measuring point of the inner wall of the ladle,the calculation algorithm of the wall thickness of the ladle and the construction algorithm of the temperature field of the inner wall can be designed.The principles of the algorithm are as follows: the measurement coordinate system and the ladle coordinate system are constructed separately,and the distance of the measuring point is converted into the coordinate information of each point of the inner wall of the ladle by using three-dimensional mapping,and the wall thickness information is obtained by comparison with the ladle reference model.The temperature field distribution information of the inner wall of the ladle can be obtained by combining the measured coordinate values of each point on the inner wall of the ladle and the measured temperature value.3.Error analysis of ladle wall thickness and temperature field measurement systemThe error analysis is mainly performed for laser sensors,infrared temperature sensors and three-dimensional rotating platforms.The effects of measuring distance,reflectance and ambient temperature on the accuracy of the laser rangefinder and the infrared temperature sensor are discussed.The control errors of the three-dimensional rotating platform are analyzed from the sources of the errors.Combining experiments and theoretical analysis,it is concluded that the measurement station and the installation position of the measurement system selected in this paper meet the measurement accuracy requirements of laser rangefinders and infrared thermometers;the ambient temperature has a certain impact on the accuracy of infrared temperature sensors,and It is proposed that this paper is equipped with industrial air conditioners to reduce the errors caused by ambient temperature;the effects of natural disturbances,mechanical errors,sensor or electronic component errors,and electromagnetic radiation on the three-dimensional rotating platform are analyzed,and solutions are proposed.