VALVE-AND-PACKER MECHANISM Russian patent published in 2003 - IPC

FIELD: oil production. SUBSTANCE: invention is meant to communicate and separate hole clearance from pipe clearance while completing, processing and cleaning critical area of formation in wells where hydrodynamic characteristics deteriorated because of precipitation of salts during acidic treatments, fouling with components of drilling mud, cement. Valve-and-packer mechanism has valve unit with holes, bottom-hole packer, liner with radial holes and gland. Valve unit comes in the form of hollow tube placed in space of bottom-hole packer and is screwed simultaneously with bottom-hole packer on to adapter and is mounted for downward movement to communicate pipe clearance with space under packer while packer is set. Bottom- hole packer has male thread on its lower part for attachment of liner. EFFECT: enhanced operational characteristics, reliability of control and simplified design of mechanism. 2 dwg