Three-stage stratified production string

Abstract

The invention discloses a three-stage layered commingled production string. In order to overcome a defect that a production string cannot simultaneously exploit more than two oil layers in the prior art, the three-stage layered commingled production string is characterized in that the lower end of a tubing string is sequentially fixedly provided with a primary pump, an upper packer, an oil tube I, a suspension nipple I, an oil tube II, a secondary pump, a suspension nipple II, an oil tube III, a lower packer and a tail pipe, wherein the primary pump is positioned on an upper oil layer; the upper packer is positioned between the upper oil layer and a middle oil layer; the lower packer is positioned between the middle oil layer and a lower oil layer; internal threads at the lower end of the suspension nipple I are fixedly connected with the upper end of a seal cartridge; internal threads at the lower end of the suspension nipple II are fixedly connected with the upper end of a pump cylinder of a triple-stage pump; a hollow sealing rod of a plunger assembly is positioned in the seal cartridge; the diameter of the hollow sealing rod is smaller than the diameters of a primary pump plunger and a secondary pump plunger. The three-stage layered commingled production string has the beneficial effects that different oil layers are simultaneously exploited by feeding a string once, and the exploitation efficiency is improved.

Description

technical field [0001] The invention relates to a crude oil production and recovery pipe string, in particular to a three-stage layered combined production pipe string suitable for simultaneously exploiting crude oil in different layers in the next pipe string. Background technique [0002] Due to the geological characteristics of the reservoir, the oil layers are usually distributed in multiple layers vertically, and most of them are heterogeneous reservoirs. During the production process, interlayer interference exists in a large range, especially for oil wells with high production and rapid water cut rise in the early stage of production. . The traditional single-stage oil production pump is used to exploit multiple oil layers, which is inefficient due to interlayer interference and cannot fully utilize the development timeliness. The oil field publicly uses two-stage layered oil well pumps, and one pump can only achieve layer separation of two layers It is impossible to...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the deficiency that the existing oil production string cannot achieve the purpose of simultaneous exploitation of more than two oil layers, the present invention provides a three-stage layered combined production string

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