The Research Of On-line Intelligent Circle Cutting On Gas Transporting Pipeline Under Pressure

With the rapid development of industrial production and the marked improvement of the people's living standards, the transport of gas through pipeline has become increasingly popular. During this process, it comes to be a thorny problem that to assemble branch pipeline securely and efficiently without any halt of gas transport and pressure loss. The branch pipeline installation machines appeared at present have a poor performance on efficiency and security. Moreover, they are useless to assemble large-scale branch pipeline. As the technology of circle cutting on gas pipe is urgent and important for the industries and the people's ordinary life, to develop a safe, reliable, efficient and intelligent circle cutting device on gas transporting pipeline under pressure is of great economic significance.First of all, this paper introduces the general scheme of intelligent online circle cutting device and its working process. Then the author discusses the solution to improve efficiency and reliability of the device from two aspects: on one hand, the author has analyzed the process parameters of plasma arc which influence the cutting quality, founded the plasma arc cutting mold by using the theory of thermodynamics and studied how to regulate the cutting speed. On the other hand, the author has analyzed and designed the cutting flame swing mechanism, analyzed the working process of circle cutting process on the pipeline, and improved the cutting quality. By means of comparison and analysis, The author chooses thickness measurement technology of ultrasonic and angle measurement technology of resolver transformer which lay the foundation for the design of the controlling system of cutting flame swing mechanism.According to the characteristics of cutting flame swing system, the author finally has accomplished the design both of software and hardware for the controlling system, developed the card which is based on singlechip, to control the swing of cutting flame; compiled the whole system's software with Visual C++, and analyzed the interferential resources of the controlling system of cutting flame swing mechanism and discussed the anti-interference measures.Verified by practical tests, every performance target of the above studies has reached the desired goal, and to cut a hole on the gas pipeline with the guarantee of being safe, efficient and reliable has become a reality. This study has manifested great economic and social benefits.