Method for selective treatment of a producing formation, device for the implementation thereof and hydraulic fracturing port

A method for selective processing of a number of intervals of a productive formation, comprising the steps of:

• providing a borehole associated with the productive formation;
• providing a well casing within the borehole;
• providing a tubing string inserted into the well casing;
• said tubing string defines a string external surface;
• providing a device essentially coupled with the tubing string;
• said device defines a device external surface;
• the string external surface and the device external surface together form a common external surface;
• wherein an annulus is defined as a space between the common external surface and the well casing;
• said device includes:
• an upper packer and a lower packer defining an inter-packer space therebetween;
• a hydraulic fracturing port located in the inter-packer space;
• a mechanical anchor located below the lower packer;
• and a perforator being in controllable hydraulic communication with the tubing string, and located below the mechanical anchor;
• lowering said device into the well casing to a depth corresponding to the productive formation;
• positioning said device at a predetermined interval chosen from said number of intervals;
• supplying pressurized working fluid through the tubing string to the perforator;
• carrying out a perforation of the well casing by the perforator, by punching sidewalls of the well casing and creating caverns in sidewalls of the borehole within the predetermined interval;
• providing washing out of the caverns;
• bringing the perforator into a transportation position;
• positioning said device so that the predetermined interval is located between the upper packer and the lower packer;
• fixing said device in the well casing using the mechanical anchor;
• blocking access of the working fluid to the perforator;
• supplying fracturing fluid under pressure into the tubing string and into the inter-packer space;
• activating the upper packer and the lower packer thereby providing separation of the predetermined interval from the annulus;
• providing hydraulic fracturing of the productive formation by the fracturing fluid;
• reducing a pressure of the fracturing fluid in the inter-packer space;
• transferring said device into the transportation position;
• and removing said device from the well casing.