Abstract: In the middle and late stages of oilfield development, due to the severe formation deficit and the intensified sand production in the oil layer, an effective circulation was not be established through the conventional sand flushing process or the use of temporary plugging agent for sand flushing, thus affecting the normal production of oil wells. The self-priming continuous sand flushing process for low pressure absorption wells is one of the effective technologies to solve this problem, but in actual use, there are problems such as cumbersome procedures, large loss of sand flushing fluid, and sand plugging. To this end, supporting tools such as two-stage integral pipe string and forced circulation valve have been developed, thereby improving and perfecting the self-priming continuous sand flushing technology for low pressure absorption wells. This technology has been applied for 300 well times, restoring oil well productivity up to 5000t, with good application results. This technology can provide technical support for the resumption of production of oil wells with sand production due to formation deficit.

Key words: sand production, sand flushing, formation deficit, forced circulation valve