VALVE UNIT Russian patent published in 2003 - IPC

FIELD: equipment for extraction of hydrocarbons and installation of packers of hydraulic action. SUBSTANCE: valve unit incorporates enclosure and hollow shaft with packer, radial holes and conduits. Spring-loaded differential bushing with internal groove and packer is installed between enclosure and hollow shaft. It is fixed by shear screws to prevent movement of locks in conduits of hollow shaft. Locks interacting with sealing seat through collar are positioned in conduits. Sealing seat is mounted in hollow shaft for axial downward movement. Enclosure, hollow shaft and spring-loaded differential bushing form space hydraulically coupled through radial holes located above sealing seat to space of hollow shaft above sealing seat. Hollow shaft and spring-loaded differential bushing also form space hydraulically coupled through radial holes located under sealing seat to space of hollow shaft under sealing seat. Spring-loaded differential bushing is mounted for upward movement and movement to extreme lower position for radial travel of locks in internal groove in spring-loaded differential bushing and release of sealing seat. EFFECT: raised reliability of installation of packer in wells thanks to prevention of hydraulic shock when valve unit operates. 1 cl, 1 dwg