Bore-hole-jet device for formation testing and a prestarting procedure for said device

Abstract

The invention relates to fluidics, in particular to jet devices for lifting various liquids, essentially for lifting petrol out of wells and for well examination. The inventive jet device comprises a packer and a flow column provided with a bearing assembly. Bypass openings are embodied in said bearing assembly and a jet pump is arranged inside the body thereof. A channel for running a medium mixture off the jet pump into an annular space connected to the bypass openings, a channel for supplying fluid pumped-out from the well to the jet pump and a channel for supplying ejecting medium to a nozzle of the jet pump are embodied inside the body. In addition, a pressure-sealing unit is arranged in the channel for supplying the pumped-out fluid in such a way that it is superposed with respect to the jet pump. A bypass channel is embodied in the pressure-sealing unit in such a way that it enables a logging cable to be passed through said channel and the channel for supplying the pumped-out liquid. The logging cable makes it possible to arrange instruments and equipment in the well below the jet pump in such a way that they can move along the borehole.