Research Of Rotary Drilling Rig Rotary Automatic Positioning Control Technology

Being widely used in foundation engineering construction of China, rotating drill rigs are large piling equipments which are mainly used for drilling operation with large diameter and deep foundation pile. Rotating of upper part of the rotating drill rig is a frequent operation while it is working. At present, rotary positioning operation of rotating drill rig mainly relies on manual control in our country, which severely restricts the construction efficiency and the drilling quality. With the development of technology and society, intelligent control has become the development direction of the rotating drill rig in the future. Combining the R&D project of rotating drill rig intelligent control system in Sunward Intelligent Equipment Co. Ltd., this paper studies the rotating braking stability of multi-function rotating drill and the dynamic characteristics of hydraulic system. A safe and efficient scheme of rotary positioning control is designed. This paper mainly includes the following works:Rotating braking stability of rotating drill rigs is analyzed by using the principle of the kinematics and a space coordinates system is set up by the application of the D-H method. According to the principle of mass center equivalent, the mass center of the drilling is solved and dynamic stability angle of the rig under the condition of braking is calculated. Using MATLAB Simulink simulation software, simulation study on the dynamic stability of rig is carried out. Factors that influence the stability of rotary braking are found. Thereby, safety of rotating drill rig in the process of rotary positioning is ensured.The rotary starting and rotary braking of rotating drill rigs are researched. System modeling is built by AMESim hydraulic simulation software and simulation analysis of dynamic characteristics of rotating hydraulic system is conducted. The influence of buffering Valve parameter settings on the starting and braking of a rig is investigated. Thus the foundation for designing rotary control scheme is laid.In accordance with the principle of electro-hydraulic proportional control, rotary positioning control program of rotary drilling rig is designed. Mathematical model of Rotary control system is built and Dynamic characteristics of rotary control system are analyzed. The neural network adaptive PID control algorithm is incorporated into the rotary control system. Taking the advantage of software interface technology, a combined simulation model of rotary control system is set up. The research shows that rotary control scheme put forward in this paper enjoys a faster system response and higher precision of positioning. To ensure the successful operation of the control scheme, the hardware circuits that could meet the control requirements are designed and perfect automatic rotary control process is formulated.Finally, this paper puts SWDM-28based rotary drilling rig as an experimental prototype to test pressure and flow curves during rotary motion and verify the correctness of the simulation model. By comparing the stability and positioning accuracy of the rotary system using ordinary PID control algorithm and neural network adaptive PID control algorithm, the feasibility and effectiveness of the rotary control methods in this paper are proved.