The tree is a wellhead device from a spray well. The utility model is mainly used for hanging down the tubing string in the well, sealing the annular space of the oil casing, controlling and regulating the production of the oil well, and ensuring the daily production management of operation, construction, oil admission, nesting data, testing and waxing.

Blowout preventer is used to test well, workover, completion and other operations shut down the wellhead to prevent the blowout accident occurs, the full seal and semi-sealed two functions together, with a simple structure, easy operation, high pressure and so on , Is commonly used in the oil field to prevent blowout safety seal wellhead device. Oil drilling, installed in the wellhead casing head, used to control high-pressure oil, gas and water blowout device. BOP shut down (shut-off) the wellbore when the pressure in the well is high. Pressure from the drill pipe into the heavy mud, the four-pass under the gate, can be replaced by the invasion of the gas invasion, increasing the pressure of liquid column wells BOP, tree and wellhead blowout preventer to suppress the difference between high pressure oil and gas The jet.