A flaw in all widely used methods of hydraulic fracturing is that high pressure is applied not only to the wells that are treated from the surface but also to the adjacent wells. If hydraulic fracturing is performed in old wells with longstanding history of reservoir recovery, then it is very difficult to ensure that the well endures the pressure in terms of failure of the fracture and the cemented section of its behind-the-casing chains in the area of the conductor string which, unlike the production string, is fixed with a lower strength value. And where there is a ‘weak link,’ you can always expect a rupture in the casing string.

Among other flaws is the fact that mobile fleet units do not build up the required design pressure simultaneously and such inconsistence has an adverse impact on the well support and upsets the casing string.

It is possible to avoid adverse effects by using fraccing fleet only partially, e.g. using only one 100–120 MPa high-pressure pump unit depending on the depth of the hole. The remaining fleet units may be redundant.

It turns out that it is possible to create a fracture in the body of the formation if in order to perform hydraulic fracturing a pipe string with hydraulic jet pumps is lowered into a producing oil or gas-bearing bed.

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