One of the methods of oil production intensification is water vapor injection into oil reservoirs. The efficiency of this process generally depends on the amount of useful heat utilized in the oil reservoir. One of the most important parameters of thermocouple treatment of the reservoir is the amount of heat di rectly supplied to the oil reservoir. For its determination it is necessary to know the heat energy losses in surface communications and oil wells, as well as losses associated with heat exchange processes in the oil reservoir and surrounding rocks. High heterogeneity of oil reservoirs complicates the use of continuous steam injection into oil reservoirs. The time required to warm up the reservoir to a given temperature is a determining factor for theoretical analysis of heat losses due to the unsteady heat exchange process in such conditions. The paper presents the basic principles of the heat loss estimation method, as well as the results obtained in determining the relationship between the time required to warm up the oil reservoir to a given temperature and the temperature of steam.
