The Rotary Kiln Shell Ovality Measurement System Based On LabVIEW

The rotary kiln is the center equipment in the cement production. It works in the circumstances with big strength and high temperature for long. As the Crucial equipment, it has vital significance that the kiln keeping a good work. The inside of the shell was built firebricks for separating the heat. The kiln was working for long time, and the firebricks were wore out by all kinds of cement materials, so the firebricks may become thinner and thinner, or the kiln's center line is not straight so the kiln shell could suffer from the force, because of the force the firebricks inside the shell may break down. If the firebricks break down, it could induce "the red kiln" accident. If we don't stop this phenomenon, the shell can be burned out so it can cause much bad producing accident. If there is such an accident, the kiln will stop working and it will bring the cement company economy losing. So we must ensure the kiln to be in good conditions is very important. For avoiding such accidents, we need such an instrument which can measure the deformation of shell and calculate the value of shell ovality. According to the ovality, we can diagnose if the firebricks were become thinner or broken down. If there is something problem, the cement factory could take measures to repair the kiln.In this thesis, we research and analysis the reason of shell ovality as well as its measuring methods both in the domestic and foreign country. Contrasting to the process analysis, we get the new method to measure the ovality of shell and how to deal with data. We also design out the ovality instrument, and the instrument has been used very well.The article introduces the measuring principle of shell ovality and deduces the ovality formula for detail. Then, the paper illuminates how the device was designed out. It contains mechanical device designing, the interface circuit between sensor and computer designing and the software designing. In our device, we take an innovative designing that we sent the measuring data to the computer by wireless circuit. By taking this method, we can collect the measuring data at the scene, and immediately the ovality curves can be displayed in the computer, also the value of shell ovality can be calculated out. In the section of software, we use the LabVIEW from NI company. This software has much better man-machine contact surface, we can get the result and curves conveniently.Because of technology monopoly, the price of the ovality instrument designed by foreigners is very high, so many cement factories in domestic can't afford the device. So we design the first ovality instrument, it breaks down the foreign technology monopoly, and its cost is much lower. It can serve for majority of Chinese cement companies, and have good marketing competition.