Research Of Control System About Axial Force Tool For Deep-Water Pipeline

With the wearing out of the world's petroleum resource, ocean gradually becomes the focus of the global petroleum exploration . It is the general trend to explore ocean petroleum and gas from shallow to deep sea . Because of our key technology and equipment are relatively backward in deep-sea petroleum and gas exploration, deep-sea petroleum and gas development is still in its infancy. Main contents of this paper come from the 863 subjects "Pipe laying technology at the deep sea" which mainly studies the axial force tool of pipe initial connecting equipment to prepare for the exploration of petroleum from the deep sea.The international and domestic development of pipe initial connecting equipment is introduced, the researching contents of the axial force tool control system is put forward. This control system is carried on the basis of mechanical design ontology , according to the axial force tool's actions to complete , the total hydraulic system design is finished , working principle of the hydraulic system is analyzed, the main function loop of the hydraulic system is identified , and hydraulic components of pumps and valve etc are selected.Adjusting device is an important part of the axial force tool , its horizontal and vertical adjustment devices (front-end or back-end)are two hydraulic cylinders as implementation components, therefore the control of the adjusting device is the issue of double synchronous control. According to comparative analysis to several commonly used open-loop and closed-loop synchronization loop, horizontal and vertical adjusting devices are determined with master-slave synchronization of closed-loop controlled by dual-proportional valve.In this paper, the electro-hydraulic proportional control system of the vertical adjusting device is analyzed, mathematical models of proportional directional valve, asymmetric cylinder controlled with proportional valve and sensor are established,simulation models of location and synchronous system of hydraulic cylinders controlled by proportional directional valve are determined , The upstream and downstream motions of hydraulic cylinder piston rod are simulated through the SIMULINK toolbox of MATLAB language, correction is done with location-type PID and improved PID, constant compensation methods of the proportional valve median dead zone are put forward to reduce its effect.Finally, the PLC control system is designed, the overall program is determined , hardware selection of PLC, A/D, D/A is Completed , I/O distribution of PLC and hardware diagram is carried out , software flow chart is given at the same time.