Abstract: The layring polymer injection is the one of the effecyive ways enhancing oil recovery. At the present, thereare 302 wells in central Saertu development area in Daqing oilfield having been practiced layring injection, which take up 37.6% of total wells, the way has played a unreplacible role in polymer flooding recovery. But impacted by the multiple factors such as adaptability of reservoirs and layring injection technique, the way needs furtherly improved in practice. Through the analysis to reservoirs production dynamic situation of layring polymer injection wells in different polymer injection stages, dynamic change and production, the wellselecting rule and layring time of the layring wells are described, the adaptability and the existing problems of layring injection technique analyzed, which offer basis for furtherly improving layring polymer injection technique.

Key words: polymer flooding, layring technique, testing, water absorption profile, EOR