Hot Rolling Thickness Measurement System

In iron and steel industry, steel rolling is always the important link of themetallurgical industry. In the plate and strip rolling production line, various qualityindicators of finished strip: thickness, shape, width determines the value of strip steel.Thickness was an important indicator of quality that measured the strip, the domesticand foreign metallurgical industry pays close attention to extensively. Rollingequipment automation measurement level is the key to the steel strip productspecifications and quality, occupies an important position in hot rolling production, itis the exact measurement that make sure the rolling mill thickness control system toobtain accurate parameter, and affect the precision of products and productionefficiency. The production of products not only to meet the quality requirements mustalso consider the cost, single chip microcomputer as a very extensive use, with a morecomprehensive function of the micro controller, is widely used in chemical industry,construction, metallurgy and other industrial fields.In this paper, the hardware circuit of measurement system is analyzed anddesigned, based of single-chip processor as slave processor, and computer as PC.First of all, this paper introduce the structure and the working principle of X raythickness gauge, and in the basis of X ray attenuation law after transmitting material,expounds the X ray generating device principle, detection device principle, and itsinfluence factors of the stability of X ray thickness gauge in detail, and get theprinciple formula. At the same time, it is analysis from the spectrum that X rayintensity is influenced by X ray tube voltage and tube current.Secondly, it gives design of the software, X ray calibration curve fitting functionis soled, piecewise fitting method of data process is used based on the least squarecurve fitting method, in order to reduce the error caused by the change of X rayattenuation law, improve the measurement range of the system. At the same time, itanalyses the effect of thickness interference factors, such as alloy composition,environmental temperature, sensitivity and resolution, and analysis several measuresfor alloy compensation and temperature compensation to improve the thickness measuring system.Thirdly, system hardware is designed that STC89C52chip is used for slaveprocessor core, simulating the output signal generated by detection device of X raythickness whit the historical data off-line, amplification circuit uses ICL7650chip,filter circuit shields various kinds of interference signal, collecting and convertingmodule use AD7810chip, converting analog signal for10bit AD, ensure the systemresolution.Finally, this paper designs human-computer interaction interface, realizemonitoring, calibration curve, the compensation precision function. At the same timedesign the program flow of the system, and after testing to verify the feasibility ofsystem.