DEVICE FOR WELL WASHING AND COMPLETION (VERSIONS) Russian patent published in 2003 - IPC

FIELD: construction and operation of wells, particularly, completion and washing after their construction, servicing and also for increase of formation oil recovery. SUBSTANCE: device has body accommodating jet pump including diffuser with its hole directed upward, mixing chamber communicated with under-packer zone by means of passive medium supply channel. Central cavity is formed in cylindrical semibody. Nozzle is connected with circular bore and active medium supply channel with piston located above packer seal and is engageable with it. Made on conjugated cylindrical surfaces of piston and semibody are limiting beads forming circular cavity communicated by means of throttling holes in piston end face with circular bore encompassing the central cavity. Diffuse lower part has cylindrical segment thrusting nozzle with segment convex side facing body wall. Formed between seal and semibody cylindrical surface is gap filled with lubricant and/or antifriction powder, for instance, graphite. In other version, circular cavity is filled with liquid lubricant and is communicated with help of drainage channels in semibody with middle part of cylindrical conjugation of semibody with seal. Made above piston is circular bore communicating piston and nozzle with active medium supply channel and encompassing the central cavity. EFFECT: higher efficiency, reliability and longevity of device service. 13 cl, 15 dwg