Blowout preventer in full bore drill pipe

                                                         

Blowout preventer in full bore drill pipe is of simple structure and erosion resistance, and with its functions, it could be used to replace common blowout preventer in full bore drill pipe at home and abroad. In the state of normal circulation or under quiescent conditions, the valve plate is opened completely and receiving water course could get across clinometer etc. When fluid in stratum enters into receiving water course and jets flow conversely, the fluid diffuses in the cavity and changes lifting surface area, promoting valve plate to close in, thus the purpose of closing down passage in drilling jig is attained. The product specification meets SY/T 5215-2005 Check Valve of Drilling Jig standard, and joint screw thread meets requirements of GB9253.1.

I.Performance characteristics

1. Drilling fluid makes no erosion to valve plate when valve plate is opened completely;

2. When water valve plate is open, receiving water course gets across relevant instruments for breakouting by explosion or explosive cutting;

3. In the state of normal circulation or under quiescent conditions, when single- or multi-point directional drilling in forward direction or reverse direction is implemented, MWD passes blowout preventer in full bore drill pipe in forward direction or reverse direction; and passes through a globe at closed coring and tapped coring;     

4. To close automatically at opposite pressure ≥0.25MPa or flow rate ≥2L/s; 

5. Pressure-transmission hole could be designed for transmitting pressure after closing in, which provides reliable pressure reference for killing well (attention shall be paid that the pressure-transmission hole is not sealed after valve plate is closed down but only blowout is stopped to expediting connection of kelly bar and blowout-preventing single joint etc.)

II.Technical parameters

1.Model: FZF168/35-NC50;

2.Rated working pressure: 35MPa;

3.Joint model: 4 1/2″IF ( NC50 ) (machining possible as requested);

4Overall dimension: 510mm×168mm×71.4mm (effective length × outside diameter × inside diameter);

4. Diameter: 70mm