Anti spray device is used for testing for oil, workover and completion operations of closed wellhead, prevent blowout accident, will be closed and semi closed two functions into one, with simple structure, easy operation, high pressure resistant characteristics is oil commonly used to prevent blowout wellhead seal device.

When oil well drilling is installed on the head of the well head, the blowout device for controlling the high pressure oil, gas and water is used. When the oil and gas pressure in the well is very high, the blowout prevention device can seal the well mouth (Guan Si). From the drill rod is pressed into the mud, the gate has four-way can replace a bullied invasion of mud, increase the pressure of the column of fluid in the well, to suppress high pressure oil and gas discharge.

The type is divided into general blowout prevention, universal blowout prevention and rotary blowout prevention. The universal blowout spraying device can be started in an emergency situation, and can cope with the drilling and the empty well of any size. In deep well drilling is often in addition to the two common blowout, plus a universal blowout, rotary blowout, so that three or four kinds of combination to be installed in the wellhead.

Annular blowout preventer annular Blow-out Preventer usually equipped with a ram blowout preventer large gate, the operation will be a seal the annular space is formed between the column and the wellbore in the tube and in the well with string, also can be completed alone to seal the well, but the use of several times not, and does not allow long-term shut in well used.