METHOD OF CONSTRUCTION OF MULTI-SHAFT WELL FOR RECOVERY OF HIGH-VISCOSOUS OIL Russian patent published in 2008 - IPC E21B7/04 E21B43/02 

FIELD: petroleum industry.

SUBSTANCE: invention relates to oil and gas production industry, particularly to construction of oil and gas well clusters in underground maltha sand deposits and heavy high-viscosity oil fields. The method includes dropping a pipe string with a divertor at its end into the casing column within the interval required, cutting the casing column, successive formation of main process channels over the perimeter of the casing column by turning the divertor with the aid of a flexible pipe with a nozzle at its end, thus forming a number of main process channels. The casing column is cut by the cutter over the whole perimeter of the column in two places so that it is possible to form process channels within one seam. The divertor is fixed in the casing column so that outlet openings of main process channels are arranged within one slot in the casing column. The lower end of the flexible pipe is fitted with filters interconnected by flexible links. The lower filter is connected with the nozzle and the upper one is equipped with a packer. After formation of each main process channel and inserting all filters into it the circular space between the upper filter and the process channel is plugged with the packer. The flexible pipe is disconnected from the filters with the nozzle and is withdrawn out of the well. Then it is fitted with similar filters with the nozzle and the next main process channel is formed. On completion of formation of a group of main process channels the divertor is released and is fixed below or above the initial place of mounting in the casing column so that it is possible to turn it through a certain angle and to form additional group of process channels similar to the main ones within the limits of the second slot in the casing column. On completion of formation of the group of additional process channels and withdrawal of the divertor the process pipe string is dropped into the casing column and the packer is mounted.

EFFECT: reduction of material and financial costs and increased efficiency of operation of the multi-shaft well.

3 dwg