SUBMERSIBLE EJECTOR UNIT TO CLEAN WELL BOTTOMHOLE OF SAND PLUGS UNDER ABNORMALLY LOW FORMATION PRESSURE Russian patent published in 2015 - IPC E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: device contains the ejector pump installed on the tubing, it has casing in which coaxially with the internal tubing string a nozzle and a mixing chamber with a diffuser are installed. In the casing in parallel with the mixing chamber the axial channels for the work flow supply and connected with them radially located transverse side channels for the ejected flow supply are made. At the top end side the axial channels are connected with the ring space between the external tubing and internal tubing, and at the bottom end side - with work chamber. In the casing base a foot bearing is installed, it is connected with nozzle of the ejector pump by means of the spring loaded plunger with the possibility of movement up-down under flowing out work medium and functional insert, in it at angle 30° at least four cavitation generators are installed.

EFFECT: increased efficiency of the sand plug destruction, reduced abrasive action of the sand pulp, more deep repression on the formation is provided.

2 cl, 2 dwg