The problem of liquid loading in well bores for a great number of gas wells is considered. This problem is observed in the framework of production calculations using the simulation model. It is determined that groundless assignment of wells decommissioning criteria leads to significant errors in the assessment of cumulative gas production and well stop flowing time. Using the results of data after water breakthrough and wells stop flowing, the liquid unloading criteria in the gas wells were formed. The stationary unloading criteria depend on elevator equipment construction and critical production rates. They were evaluated, based on agreement procedure of calculated and actual liquid unloading parameters, by means of hydraulic well models. At the same time, applicability conditions for this technique were determined. In this paper, simple and sufficiently reliable methods and algorithms are proposed. They are used for accounting stationary liquid unloading criteria which are needed for right well decommission time. Moreover, the criteria make it possible to improve the predictive potential of the integrated field models and to arrange the operations for prolongation of well life. For instance, technological regime optimization and running additional tubings of smaller diameter made from coiled tubing (velocity strings) can be proposed.

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