The Design&Application Research For Hydraulic Controlling Downhole Diverter Valve

The Geological core drilling technic currently been using are all havingdownhole weak capability problems. Specifically in the lack of downhole advancedautomatic execute&intelligent control system. Because of missing downholecontrolling technic, the drilling projects can’t be effectively used for solvingcomplicated operations underground, such as coring from broken stratum anddownhole accidents. In order to solve this problem, this paper combined basic theoriesof control engineering and coring drilling technology designed a new, simple andconvenient downhole controlling mechanism.This thesis firstly introduces the basic theory&development process ofdownhole control engineering and summarize on its technical difficulties andproblems. According to automation and different controlling ways, downholecontrolling technology can be divided intoDownhole open-loop, Downholeclosed-loop and Downhole semi closed-loop. This paper focuses on Downholeopen-loopcontrol technology. The differences between the control signal separateopen-loop control mechanism into controlling by a ball, controlling by changing theweight over bit, controlling by drilling fluid and controlling by electricity.By studying open-loop control mechanism, select merit controlling by drillingfluid as the basis for the design of hydraulic control diverter valve. Taking the signaltype selection, basic dimensions formulate and the determination of control chain asthe premise to designing the various important mechanism. The designed hydrauliccontrol diverter valve includes a signal receiving, reversing, sealing and othermechanisms. Reversing mechanism also contains2mutually whirling Valve discs.Upper Valve disc is turn on high pressure liquid flow and the down Valve disc isconnect to low pressure liquid flow. Each rotation between the2discs will switch ondifferent work flow channels to driving different implementation tools. Checking the feasibility study of theoretical calculations, graphics processing andassembly of designed downhole fluid control valve. Validation, modification, andthen verify that the procedures to solve problems and deficiencies that exist in divertervalve design process.Based on new downhole hydraulic control diverter valve a pressure card coringdrill tool has been designed to perfectly solving core drilling and rope bindingproblem from technical and economic, also widen the applicable strata for the twocoring drill tools. That drill is designed to verify the value of the hydraulic controlvalve and provide reference template for the valve in the control of other undergroundwork.The new downhole hydraulic control divertervalve designed has a simplestructure, small radial size, multi control mode, a wide range of applications, and easyto control etc., it also can meet the initial geological core drilling undergroundopen-loop control needs.