Single-pressure double-valve electronically controlled combined production string and its control method

Abstract

The invention relates to a single-pressure double-valve electrical-control joint exploitation pipe column and a controlling method which are both adopted for two overlapping area oil layers with large physical property difference and span in a single-pump joint exploitation well in the field of oil production oil fields. The pipe column comprises a ground control system, a transmission cable and a downhole control system. The downhole control system comprises a pressure transmitting oil pump, a cable passing tubing anchor, a first control valve, a cable passing packer and a second control valve which are all connected in sequence. The first control valve and the second control valve are connected with the ground control system through the transmission cable. The controlling method of the single-pressure double-valve electrical-control joint exploitation pipe column mainly comprises the steps of sending out instructions to the downhole control system through the ground control system, adjusting opening of the first control valve, controlling inflow amount of liquid of an upper layer entering an oil pipe so as to reduce liquid inflow pressure of the upper layer and reduce interlayer disturbance to a lower layer caused by the liquid inflow pressure, fully amplifying production differential pressure, adjusting parameters of pressure of each layer and yields and the like in real time through the ground control system, finding a pressure balance point, and achieving the goal of joint exploitation continuous stable production of two oil layers.

Description

technical field [0001] The invention relates to a single-pressure, double-valve electric-controlled combined production pipe string and a control method used in a single-pump combined production well for two sets of oil layers with large differences in physical properties and large spans in a superimposed area in the field of oil recovery oilfields. Background technique [0002] When co-producing two sets of oil layers with different physical properties and a large span, in the prior art, one is to use a single-pump separate pumping string to isolate the two sets of oil layers, and the pump hanger is located at the top of the lower oil layer As mentioned above, the method of plugging is used to realize the combination of the production string and the discarded string into one to realize the form of simultaneous pumping and combined production; the second is the double-inlet liquid pumping pump, which uses the packer to separate the upper and lower oil layers. The solid conn...

AI Technical Summary

Problems solved by technology

If two oil layers are co-produced with bare pipes, since the pressure of the upper layer is high, the pressure of the lower layer is small, and the span between the two layers is large, the pressure of the upper layer plus the pressure of the hydrostatic column between the two layers will cause serious interlayer interference to the lower layer, making The lower layer is "squeezed to death" and does not produce liquid; if the lower layer is mono-mined, because of its low pressure and rapid drop in liquid production, continuous production cannot be performed, which brings greater difficulty in production management and maintenance, thereby increasing production costs, and cannot be used for various Real-time separate control of layer production fluid, unable to measure layer production and water content, and the lower layer cannot be measured because the packer separates the lower layer

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