Modified composite containing cavity sand control well completion screen pipe with flow dividing function

Abstract

The invention relates to a modified composite containing cavity sand control well completion screen pipe with a flow dividing function. The sand control well completion screen pipe sequentially comprises a base pipe, an inner layer filter screen, an outer layer filter screen, a modified multi-size-fraction pre-filling layer and an outer covering protective cover from inside to outside. The inner layer filter screen is arranged outside the base pipe in a sleeving mode. The outer layer filter screen is arranged outside the base pipe in the sleeving mode; the modified multi-size-fraction pre-filling layer is arranged between the inner layer filter screen and the outer layer filter screen; the outer covering protective cover sleeves the outer side of the outer layer filter screen; and the modified multi-size-fraction pre-filling layer comprises a first pre-filling layer and a second pre-filling layer, the first pre-filling layer and the second pre-filling layer are arranged in a spaced and staggered mode in the axial direction of the base pipe, the first pre-filling layer and the second pre-filling layer are filled with ceramsite, and the grain sizes of the ceramsite in the two pre-filling layers are different. According to the screen pipe, gas and a solid-liquid mixture are effectively shunted in the inflow process, the gas circulation performance is guaranteed to a large extent, meanwhile, the sand blocking performance is considered, excessive blocking is avoided, and the high permeability is achieved. High sand blocking performance and high circulation performance are both considered, the stability of the pre-filling layer is high, and the service life of the sand control well completion screen pipe is long.

Description

technical field [0001] The invention relates to a modified composite cavity sand control well completion screen with diverting effect, which belongs to the technical field of oil and natural gas and natural gas hydrate downhole drilling and production tools. Background technique [0002] Natural gas hydrate has the characteristics of high energy density, low combustion pollution, and abundant reserves on a global scale. It has great potential for development. At present, the trial production of natural gas hydrate has been carried out in the Mallik mine in Canada and the Alaska land area in the United States. Various degrees of sand production problems have occurred in all of the wells, resulting in serious clogging of the downhole sand control media and reduced overall production capacity, seriously affecting the test production process. [0003] If the formation sand carried by the fluid enters the sand-retaining medium, the intruded formation sand inside the sand-retainin...

AI Technical Summary

Problems solved by technology

[0007] 1) The pre-filled particles are fixedly filled by slotting or wire-wrapped media, which have poor erosion resistance under complex flow conditions in natural gas hydrate reservoirs, are prone to erosion damage, and have a short effective period of sand control;

[0008] 2) The filling material and filling particle size are single, the formation sand intrusion and clogging range is large, and the overall clogging is serious;

[0009] 3) Prepacking gravel size design and material selection cannot adapt to the geological and production conditions of natural gas hydrate muddy silt fine sand reservoirs

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