DEVICE FOR WELLHEAD SEALING Russian patent published in 2012 - IPC E21B33/10 

FIELD: oil and gas production.

SUBSTANCE: invention refers to oil and gas industry, namely to device designed for wellhead sealing that can be used in the course of construction, oil and gas wells repair as well as accidents elimination. The device includes guide rod 1 that has support elements 2 on it, block assemblies 3 and shut-off assemblies 4. Support elements 2 are done in a form of collars that embrace guide rod 1. Block assemblies 3 contain spring-loaded bushes 6 with levers 15 kinematically connected to them on the ends of which there are eccentrics performed in a form of rollers 8. Shut-off assembly 4 is done in a form of movable shutters 7 kinematically connected to bushes 9 with provision of overlapping the inner section of well 10. Note that the lower part of guide rod 1 is done in a form of a pin 11 that is located on one axis with rigidly connected pipeline 12 on the upper end of which there is a valve 13. There is a hole 14 in the side surface of pipeline lower part. Note that shut-off assembly 4 is attached above the said hole.

EFFECT: increase of reliability of its attachment inside the well, extension of possibilities due to provision of controllable formation fluid extraction after closing the well.

9 cl, 7 dwg