Research On The Control System Of Oil Extraction Joint Station Based On PLC

Water injection well of under-balanced workover operation is to fish out and unfreeze the water injection string and components and mill and reshape the casing in close circulation condition by well bore pressure control to the point that the pressure of well is less than the formation pressure,which is realized by killing fluid and blowout prevention device.By studying on the pressure control device and kinds of technology needed by high pressure water injection well workover operation,we can perform under balance workover operation on the well.The device that this study needs include:BOP stacks and hydraulic control device,flow rate controlling and monitoring device,killing fluid refine and adjusting device,power assistant device,plug tools of casing and DP and downhole string,mud filling system.Mainly study on the following content1. Well head sealing and blowout preventing technology:use BOP stacks properly to carry out blowout prevention,sealing,tripping in and out,rotating operation.2. Well bore pressure controlling technology:control the well bore pressure by monitoring the density of fluid and readjusting the property of fluid in time.3. Annular pressure control technology:well head pressure control by monitoring and adjusting the fluid of the outlet and inlet real time.4. Fluid making and mixing technology:design water and gas resistance,stable fluid and adjust the property of it when location need any time.5. Technology of unfreezing and fishing out components of water injection well and milling and reshaping in close circulating condition.