The performed analysis shows that permeability depends not only on the true value of this parameter, but also on the state of the bottomhole and bottomhole zone of the gas well, which in practice is called apparent permeability. The comparison of these two permeability values immediately reveals the change and degree of influence of the hydrodynamic perfection of the well. Changes in these parameters will naturally affect the productivity of this well. In this case, it is necessary to increase the permeability of the bottomhole zone of the formation and weaken the parameter of hydrodynamic imperfection of the gas well. The change in permeability in the bottomhole zone in the wells affects the shape of the initial section of the bottomhole pressure tracking graphs. Contamination of the bottomhole zone must sometimes be taken into account when solving nume­rous problems of development and exploitation of gas field. The more intense the formation of contamination in the bottomhole zone, the worse the porosity and permeability, which ultimately leads to a decline in well productivity. To take into account the above phenomena, the concept of "skin factor" is introduced, which takes into account the degree of influence of pollution formation on productivity. Practically, significantly reduces the gas well production rate. The paper provides a method for taking into account the influence of the skin factor on the gas well consumption, which allows you to regulate its emergence and proactively offer methods for combating these processes.

Keywords: productivity, skin-factor, pseudo-skin-factor, complete skin-factor

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