PREVENTER Russian patent published in 2004 - IPC

FIELD: oil and gas extractive industry.

SUBSTANCE: device has body with axial channel, left and right screw-thread dies mounted on guides and having compacting collars for pipes sealing, which pipes are lowered into well through axial channel in body. For sealing well in case of absent pipes in axial channel a gate is used. Driving mechanisms for left screw-thread die and gate are placed on one common side cover. Driving mechanisms for right screw-thread die is placed on another separate cover. Guiding elements of right screw-thread die are placed lower than guiding elements for left screw-thread die for value enough for free placement of left screw-thread die on guiding elements of right screw-thread die. Left screw-thread die driving mechanism provides three operation positions for it: closed, open, dismounting. In closed and open positions left screw-thread die is placed on guides of left screw-thread die. In dismounting position left screw-thread die is placed on guides of right screw-thread die and in same moment is outside the kinematical connection to driving mechanism of left screw-thread die.

EFFECT: minimized vertical dimension of preventer, lower laboriousness of field maintenance.

13 dwg