It is known that completion is presently carried out either through perforation using bullet or shaped-charge perforators, abrasive plastic perforation, or abrasive perforation using an abrasive jet to cut a fissure for the production of hydrocarbons from the string.

It should be noted that those methods of well completion have been successfully used in the oil and gas industry although they have almost similar disadvantages since their field implementation does not account for lithologic-and-facies conditions of the reservoir and interlayers in general. At a certain stage of the production of the reservoir the deposit may have and usually has still unused parts of the formation that were not taken into consideration when assessing the oil and gas reserves. Unaccounted lithologicand- facies conditions of the formation at one of the stages of the reservoir production can cause negative pressure with all the resulting adverse consequences (loss of the circulation of flushing fluid, intensive bridging with drifting sand, disruption of the integrity of the reservoir).

As a result of the negative pressure instead of the ‘bottom-up’ movement of the fluid, it will go back to the formation, or using the professional vernacular ‘a loss of circulation’ will occur. That’s why at the stage of secondary or tertiary methods of hydrocarbon production it is not possible to optimize financial costs required to lift one ton of produced oil, although with high oil and gas recovery ratios it should not have taken place.

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