Abstract: When the inter-pumping process is applied to the sand wells with insufficient fluid volume, particles may deposit and the pump may be buried as the off time gets too long. Sand settlement and compacting process of depositing matter are analyzed systematically. Combined with relevant theories and corresponding empirical formula, settling velocity of sand group and the time that the dry bulk density of the depositing matter of certain diameter tends to be stable are obtained, and the opening condition of pump valves is obtained. Based on given corresponding parameters, effect of the settling time of sand group on the inter-pumping time of pumps is analyzed, and the inter-pumping time is obtained. Moreover the correlation curve between the inter-pumping time and the sand concentration or particle diameter is drawn. The study in this paper could provide some ideas for draining sand in oil and gas extraction.