Geological conditions, technological errors and miscalculation, cracking in the cement stone of the annular space during well operation and a number of other factors cause intercasing pressure (ICP).

Modern technologies and materials allows to adequate eliminate ICP but by far not in all wells and not always successfully. A large percentage of wells is abandoned due to the failure to eliminate ICP at the well-head. Perforation of the intermediate casing and placing of a pressurized cement plug with subsequent drilling out is not always effective either.

It is no secret that oil and gas production at all stages poses threats to the environment. A lot of attention at present is given to the diagnostics of the technical condition of the well and the well equipment. Inadequate focus on diagnostics in future can lead to prolonged elimination of identified flaws and increased costs of operation or abandonment of the well.

Temperature fluctuations, casing pressure testing, round-trip operations and rotary drilling produce an impact on the casing which, though insignificant, is still sufficient to initiate cracking in the cement sheath. Microflaws in the cement stone against the casing shoes start appearing as early as during well construction. After analyzing the results of three-component geoacoustic logging (TCGL) to identify the source of intercasing pressure and cross flows, we’ve come to the conclusion that ICP inevitably appears even in wells with good sonic and temperature values of cement bond logging.

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