HYDRAULIC PACKER Russian patent published in 2009 - IPC E21B33/12 

FIELD: oil and gas production.

SUBSTANCE: hydraulic packer consists of a hollow mandrel, whereon there are secured an anchor with bowl slip sockets, spring-loaded in radial direction, and a shell forming circular cavity with external surface of the stem; the packer also consists of a sealing component, of a bushing-pusher with radial slots and a radial opening communicating with circular cavity, of cams installed in radial slots of the bushing-pusher, fixing it on the stem and designed to perform axial displacements, of a piston connected to the bushing-pusher with shear screws. A cone is rigidly connected with the piston, a ram holder with radial slots is secured on the stem with shear screws, screw-thread dies with end collars, arranged in radial slots of the ram holder, are assembled on the stem. There is a cylinder fastened on the bushing-pusher and a ratchet assembled on the cylinder for fixing the cylinder relative to the piston. According to the invention the packer is equipped with upper and lower stay nuts with internal circular lug; the nuts are correspondingly secured on the anchor and on the bushing-pusher, with a stop ring installed on the shell and designed to interact with the circular lug of the lower stay nut; also the shell has an external circular lug installed in the anchor, designed to perform axial displacements and to interact with the circular lug of the upper stay nut; while the sealing component is located on the shell between the upper and lower stay nuts.

EFFECT: increased reliability of packer operation.

2 cl, 2 dwg