PUMPING UNIT Russian patent published in 2002 - IPC

FIELD: oil producing industry. SUBSTANCE: proposed pumping unit is designed for acting onto oil bearing bed by creating differential pressure with subsequent completion of well and bringing the well to operating conditions without carrying out killing operations. Unit has tube string, jet apparatus, and packer. Jet apparatus housing is made doubled, with inner movable part containing active nozzle and mixing chamber installed for axial displacement, and diffuser which is provided with valve. Ports made in movable and fixed parts register in extreme upper and lower positions of movable part communicating, in turn, annulus with diffuser or with active nozzle chamber, thus providing delivery of active medium into active nozzle through tube string at straight circulation or through annulus at reverse circulation. length of stroke of movable part is limited from bottom by stops and from top, by upper stroke limiter which simultaneously overlaps channel of upper part of active nozzle chamber in extreme upper position of housing movable part. Movable part of housing is provided with return mechanism made, for instance, in form of spring arranged between movable ands fixed parts of housing. EFFECT: increased oil recovery. 2 dwg