CN104213846B - Selective Production String and Working Method of Multi-Stage Fracturing Horizontal Well Completion with Casing - Google Patents

Abstract

The invention discloses a casing completion multi-section fracturing horizontal well selective exploitation tubular column and a working method thereof, which are designed for realizing the selective and section-by-section exploitation of a horizontal well. The multi-stage packer of the separation sleeve is connected outside the water-proof oil pipe of the pipe column; the water-proof oil pipe is internally connected with a deep well pump, a connecting sealing insertion pipe, a constant pressure valve and a sealing cylinder which are opposite to each partition section of the sleeve and a bottom guide plug; the upper end of the bottom-sealing perforated pipe is connected with a sealing insertion pipe, and the pipe body is connected with a constant pressure valve and a sealing cylinder in each partition section. When the horizontal well is in operation, the packer is used for separating the horizontal well section, then the sealing insertion pipe and the bottom-sealing perforated pipe are put in, the sealing barrel is combined in the separation pipe column to form a secondary sealing section, the sealing insertion pipe is dragged, and selective exploitation of the horizontal section and sectional production water exploration are carried out. The invention can be used in multiple stages, the number of stages is not limited, selective exploitation under the conditions of casing pipe micro-deformation and damage can be realized, or the exploitation from top to bottom section by section and the production and water exploration by section can be realized, the flooding of the whole well can be avoided, and the good development effect can be ensured.

Description

Selective Production String and Working Method of Multi-Stage Fracturing Horizontal Well Completion with Casing

technical field

The invention relates to a casing completion multi-stage fracturing horizontal well selective recovery pipe string and a working method thereof, belonging to the field of oil recovery technology.

Background technique

Using horizontal wells to develop low-permeability oilfields can greatly improve the development effect and increase the recovery factor. With the advancement of horizontal well drilling technology and stimulation methods, the horizontal section of horizontal well is getting longer and the number of stimulation sections is increasing. Affected by water injection development and fracture development, there are problems of uneven stress and different contributions in various layers of horizontal wells. Water flooding in part of the horizontal section will affect the whole well, rapidly increasing the water cut in the well, shortening the water-free oil production period, and accelerating the decline in production. Dynamic on-site adjustment measures will damage and deform the downhole casing, seriously affecting the development effect of horizontal wells.

At present, the selective mining of low-permeability and low-flow horizontal wells and the water detection of staged production tests basically use switch timing control and produce each layer one by one. The water content of each stage is analyzed on the ground to determine the water-producing layer. However, whether the switch of the downhole switch is normal can only be known after the end of the test. If the switch fails, the test will fail. In addition, the slight change and fouling of the horizontal well casing will make the self-sealing packer unable to run in, and cannot be dragged and pulled out when it expands when encountering oil.

Contents of the invention

The purpose of the present invention is to provide a casing completion multi-stage fracturing horizontal well selective production string and its working method, which can solve the above-mentioned technical problems and realize the selective production, stage-by-stage production and search for horizontal wells in horizontal wells. water.

The technical content of the casing completion multi-stage fracturing horizontal well selective production string is as follows:

The outer part of the tubing string is connected to the multi-stage packer separating the casing from top to bottom; The constant pressure valve and sealing cylinder of each compartment, the bottom end of the oil pipe is connected to the guide plug; the upper end of the bottom-sealed perforated tube is connected to the sealing intubation tube, and the pipe body is connected to the constant pressure valve and sealing cylinder in each compartment.

The working method of the casing completion multistage fracturing horizontal well selective production string is as follows:

First use the multi-stage packer of the separated string to separate the horizontal well section; then run the sealing intubation tube and the bottom-sealed perforated pipe, and combine the sealing cylinder in the separating string to form a secondary sealing section; drag the sealing intubation tube to carry out horizontal well section Segment selective mining and segmental production seeking water.

The invention can be used in multiple stages, and the number of stages is not limited, and can realize selective mining under the condition of slight change and damage of the casing, or mining from top to bottom section by section and seeking production and water in sections, and can avoid full well water Flood to ensure a good development effect.

Description of drawings

Fig. 1 is a schematic diagram of the selective recovery of the middle part of the horizontal well by the casing completion multi-stage fracturing horizontal well with the string.

detailed description

Example:

Embodiments of the present invention are further described with reference to Fig. 1:

The outside of the tubing string 10 is connected from top to bottom with the Y445 hand-off packer 12 of the separating casing 14, the upper packer 7 of the Y441 intubation and the lower packer 3 of the Y441 intubation; From top to bottom, connect the deep well pump 13, the sealing cannula 11 connected to the Y445 hand-off packer 12, the upper constant pressure valve 9 and the upper sealing cylinder 8 of the upper section of the opposite casing 14, and the middle section of the opposite casing 14. The middle constant pressure valve 5 and the lower sealing cylinder 4, the lower constant pressure valve 2 and the guide plug 1 of the lower section of the casing 14; Constant pressure valve and sealing cylinder.

The working method of this pipe string is as follows:

1) Run the separation pipe string: first, install and connect the guide plug 1, each packer, each constant pressure valve and each sealing cylinder with the water-resisting tubing 10 according to the number of sections and the interval between the sections, and then run into the corresponding position in the well After entering the well, the casing 14 is divided into four sections by the Y445 drop packer 12, the Y441 upper intubation packer 7 and the Y441 intubation lower packer 3.

2) Setting: Use a cement truck to pressurize 20MPa from the wellhead, hold the pressure inside the pipe, and make the upper packer 7 of the Y441 intubation and the lower packer 3 of the Y441 intubation first set; then continue to pressurize and open the upper constant pressure valve 9 , The middle constant pressure valve 5 and the lower constant pressure valve 2 communicate with the oil layer.

3) Throw the ball after depressurization at the wellhead. After the steel ball falls to the ball seat of the drop joint of the Y445 drop packer 12, use a pump truck to press it once until the pressure suddenly drops to zero. At this time, the drop inner sleeve is separated from the drop joint , take out the oil riser 10 above the hands-off joint, and all the other pipe strings are installed in the downhole.

4) Running into the production string: run the sealing intubation tube 11 and the bottom-sealed perforated pipe 6 into the water riser 10, and connect the sealing cylinders in the downhole string to form new secondary sealing sections.

5) Oil production by pumping: According to the layers to be exploited, drag the sealing intubation tube 11 and the bottom-sealed perforated pipe 6 to communicate with the oil layers in any section for extraction.

6) Pull out the separation string: firstly pull out the sealed cannula 11 and the bottom-sealed perforated pipe 6, then lower the overshot, and salvage the Y445 discarded packer 12, the Y441 cannulated upper packer 9 and the Y441 inserted cannula step by step. Down pipe packer 4.

Claims (1)

1. the method for work of a cased hole completion multistage frac water horizontal well selectivity mining tubular column, it is characterised in that separate net horizontal section first with the multiple-string packer separating tubing string；Enter down sealing again and intubate pipe with holes with back cover, form secondary seal section separating in tubing string in conjunction with sealing drum；Dragging sealing intubates, and carries out the exploitation of horizontal segment selectivity and product water detection is asked in segmentation；

The specific works step of described method of work is as follows:

1) enter to separate tubing string under: first, by hop count and certain distance requirement, it is directed to plug (1), each packer, each constant pressure valve and each sealing drum be connected with water proof oil pipe (10) installation, then G.I.H relevant position, enters the Y445 back-off packer (12) after well, Y441 intubates upper packer (7) and Y441 intubates lower packet (3) and sleeve pipe (14) is separated into four sections；

2) set: suppress 20MPa with cementing truck from well head, build the pressure in pipe, make Y441 intubate upper packer (7) and Y441 intubates lower packet (3) and first sets；Then proceed to pressurization, constant pressure valve (9), middle constant pressure valve (5) and lower constant pressure valve (2) in unlatching, link up oil reservoir；

3) pitching after well head release, after the back-off sub ball seat that Y445 back-off packer (12) fallen by steel ball, once suppress with pump truck that to fall suddenly to pressure be zero, inner sleeve of now giving up departs from back-off sub, tripping out the water proof oil pipe (10) of more than back-off sub, all the other tubing strings are arranged on down-hole；

4) enter flow string under: sealing intubated and enter in water proof oil pipe (10) under (11) and back cover pipe with holes (6), connect each sealing drum in down-hole string, form new each secondary seal section；

5) turn on pump recovers the oil: production horizon section as required, drags sealing and intubates (11) and back cover pipe with holes (6), links up the oil reservoir in any section, exploit；

6) separation tubing string is tripped out: first trip out sealing and intubate (11) and back cover pipe with holes (6), enter fishing socket down again, step by step salvage Y445 back-off packer (12), Y441 intubates upper packer (7) and Y441 intubates lower packet (3).