METHODS OF PREPARATION AND PLUGGING MATERIALS APPLICATION TECHNOLOGY WHEN WATERPROOFING WORKS ON OIL WELLS PERFORMING

Abstract

It is well known that many oil wells in the Volga-Ural Region have a high water cut degree. For the fields of PJSC TATNEFT, the average water cut is 70 %. Sometimes this value reaches 98 %! There are many reasons for this water cut level, including depreciation of the entire underground part of the well, non-compliance with technologies and the low-quality materials application in the well construction, operating rules violation. The resulting water flow between the aquifers and oil well horizons leads to a high water cut in the produced product and very often constitutes the greater amount in the produced fluid composition. To eliminate such crossflows, waterproofing works are carried out to separate the layers, which must be performed as efficiently as possible. Despite the large plugging compounds assortment and the variety application technologies, the success of waterproofing works remains low in many cases. The materials composing the plugging solutions do not always turn out to be of the required quality, and the work technologies, as a rule, are of a recommendatory nature and require amendments taking into account specific conditions. In this regard, a number of new materials, structure-forming agents and injection techniques have been proposed, which increase the waterproofing screen resistance to the formation waters breakthrough.