METHOD TO DELIVER GEOPHYSICAL INSTRUMENTS INTO HORIZONTAL WELL Russian patent published in 2015 - IPC E21B23/14 E21B47/12 

FIELD: mining.

SUBSTANCE: method is based on the fixation of downhole tools to the end of a flow string, to which the end of a cable section is connected, the length of which is comparable with the length of the vertical section of the well. During the subsequent growth of the flow string length the geophysical instruments together with the cable section and the flow string move along the horizontal section of the well to the distance from the well, comparable with the length of the vertical section of the well. Then an additional section of the geophysical cable is lowered into the well, the length of which is comparable to the length of the vertical part of the well. The lower end of this additional cable section is mechanically and electrically (by means of contactless radio wave connection) connected to the upper end of the cable section connected to the geophysical instruments and located in the flow string. After that, if required, the flow string by means of the growth of its length together with the cable in it is moved along the horizontal part of the well to a longer distance from the well. Then another section of the cable may be additionally lowered into the well and connected electrically and mechanically to the available sections in the well, connected to each other. This process of connection of another cable section to the sections already available in the well may be carried out in sequence, until the end of the flow string reaches the point most distant from the well, during the growth of the flow string, where the point corresponds to the end of the section of the horizontal part of the well intended for research. After lowering of each subsequent additional cable section into a well, it is pressed to the flow string, so that during the subsequent movement of the flow string there is no relative movement of the cable and flow string along the well. As soon as the geophysical instruments reach the intended end point in the horizontal part of the well shaft, and all required additional cable sections are lowered into the well, permanent information connection is set between the geophysical instruments and the earth surface. Afterwards the instruments are pressed to the well wall, and pressing of the cable sections and instruments to the flow string is eliminated, thus providing for the free removal of the required flow string section from the well, which is comparable to the length of the horizontal part of the well shaft intended for research. Afterwards the geophysical instruments together with the connected sections of the geophysical cable may be moved along the horizontal part of the well shaft from its bottom to the vertical section of the well.

EFFECT: increased efficiency of delivery of the geophysical instruments into a horizontal well.