CN210317257U - Expansion sieve tube - Google Patents

Abstract

The utility model provides an expansion sieve tube, which is provided with a base tube, a memory plastic polymer and an elastic metal mesh from inside to outside in sequence; the base pipe is of a hollow structure, and at least the area covered by the memory plastic polymer is provided with a plurality of slots or through holes for liquid to pass through; the memory plastic polymer is an expandable high polymer material with pores for sand prevention, can be compressed on the ground and expanded under the stimulation of preset conditions after falling to the bottom of a well until contacting with the well wall; the elastic metal net is used for protecting the memory plastic polymer and supporting the well wall. The memory plastic polymer is an SMP material. The part of parent tube can directly adopt slot screen pipe or foraminiferous pipe, forms double-deck sand control structure with the combination of the outer memory plastic polymer that has the hole, can have higher sand control effect in the in-pit use.

Description

Expansion sieve tube

Technical Field

The utility model relates to an oil field of digging, especially an expansion screen pipe.

Background

Oil layer sand production is a common phenomenon in the reservoir exploitation process, and mechanical sand control is a sand control technology which is used most; the sand control screen pipe plays an important role in a mechanical sand control mode; in the use of sand control screen pipe, in order to improve sand control effect, generally all need carry out the gravel packing, because screen pipe gravel packing operation technology is complicated, the cycle is longer and the cost is higher, appear simultaneously that depth filtration forms the silt cake layer in with the annular space and then causes the screen pipe to block up, consequently research sand control is effectual, and sand control device that the cost of action is low has important technological and economic meaning. After the expansion sand control screen pipe developed by the Weatherford company is expanded, the outer wall of the screen pipe can be attached to the inner wall of the sleeve or the wall of an open hole well, the annular space between the screen pipe and the sleeve is reduced, and the condition of increasing sand production is improved. The expansion screen pipe technology is developed at present, but the defects that the outer wall of the screen pipe cannot be tightly attached to a sleeve, the flow area is small, the production cost is high and the like still exist, and the development of the expansion screen pipe with higher efficiency and stronger practicability is a key technology in the field of mechanical sand control at present.

Chinese patent document CN 105626002 a describes a filling-free expandable screen pipe, which includes an expandable base pipe, a filtering screen pipe arranged outside the expandable base pipe, and an expansion body outside the filtering screen pipe; the expansion body comprises a shape memory polymer layer coated outside the filtering sieve tube and a water-soluble polymer layer integrally coated outside the shape memory polymer layer; two ends of the filter screen pipe are fixed on the expansion base pipe through a first positioning ring; two ends of the shape memory polymer layer are fixed on the filtering sieve tube through a second positioning ring; the two ends of the expansion base pipe are respectively provided with an expansion base pipe extension section protruding out of the first positioning ring. But the scheme has the defects that the structure realization difficulty of the expansion base pipe is higher, the cost is higher, the shape memory polymer layer is easy to damage in the process of passing through a bend from the bottom to the bottom of the well, and even the sand control effect is failed. US 8664318a1 describes a shape memory structure comprising: an elastic material; and an elastic material mixed together with the viscoelastic material, the shape memory structure being re-formable from a first shape to a second shape upon exposure to an environmental change that softens the viscoelastic material, thereby allowing the shape memory structure to creep under stress stored in the elastic body and the shape memory structure to be configured to hold the filter material (not one of the elastic material or the viscoelastic material) in a smaller volume when in the first shape than when in the second shape. This solution also has the problem that the shape memory structure is easily damaged. Moreover, the excessive thickness of the elastic material also tends to affect the flow-through efficiency, i.e. the fluid flows through unnecessary filtering paths, which increases the energy consumption.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that an expansion sieve tube is provided can form the support to the wall of a well in the pit to avoid memory plastic polymer's damage, especially when through buckling the region, can protect the outer wall of sieve tube. In the preferred scheme, the overflowing efficiency of the sieve tube can be improved.

In order to solve the technical problem, the utility model discloses the technical scheme who adopts is: an expansion sieve tube is sequentially provided with a base tube, a memory plastic polymer and an elastic metal net from inside to outside;

the base pipe is of a hollow structure, and at least the area covered by the memory plastic polymer is provided with a plurality of slots or through holes for liquid to pass through;

the memory plastic polymer is an expandable high polymer material with pores for sand prevention, can be compressed on the ground and expanded under the stimulation of preset conditions after falling to the bottom of a well until contacting with the well wall;

the elastic metal net is used for protecting the memory plastic polymer and supporting the well wall.

In a preferred embodiment, the memory plastic polymer is an SMP material.

In a preferred embodiment, the memory plastic polymer is arranged in a heating and compressing shape and gradually expands under the influence of temperature reduction after being put into the bottom of the well.

In a preferable scheme, the memory plastic polymer is set into a normal-temperature compression shape, and is gradually expanded after being put into the bottom of a well and heated by electrifying.

In the preferred scheme, the memory plastic polymer is set into a normal-temperature compressed shape, and the shape is recovered after the memory plastic polymer is put into the bottom of a well and a high-temperature liquid medium is introduced.

In a preferred scheme, the memory plastic polymer is set into a normal-temperature compression shape, an adhesive is arranged in the compression process, and the shape of the memory plastic polymer is recovered by introducing a dissolving agent after the memory plastic polymer is put into the bottom of a well.

In a preferred scheme, metal supporting nets are arranged at two ends of the elastic metal net and are arranged into a structure capable of swinging along the axial direction;

when the elastic metal net is in a compressed state, the metal support net swings towards a direction far away from the memory plastic polymer, and when the elastic metal net is in an expanded state, the metal support net swings towards a direction close to the memory plastic polymer.

In a preferred scheme, the elastic metal net is formed by combining axial metal wires and circumferential metal wires, wherein the axial metal wires are positioned at a position close to the outer layer, and the circumferential metal wires are positioned at a position close to the inner layer.

In a preferred scheme, the desolvation agent is arranged between the memory plastic polymer and the base pipe, and can be dissolved under the action of temperature or a dissolving medium after the memory plastic polymer expands.

In the preferred scheme, a memory plastic polymer section and a screen section are arranged on the surface of the base pipe in an axially staggered manner;

the screen section is provided with a hole-shaped screen pipe and a mesh screen pipe.

The utility model provides an expansion sieve tube, compared with the prior art, the following advantage has, the part of parent tube can directly adopt slot sieve tube or foraminiferous pipe, forms double-deck sand control structure with the outer memory plastic polymer's that has the hole combination, can have higher sand control effect in the use in the pit. The elastic metal net positioned on the outermost layer has certain strength, can prevent the damage to the sieve tube or the memory plastic polymer caused by the rugged well wall and the bending in the well entering process, and can cling to the well wall after the memory plastic polymer is opened, thereby having better supporting and protecting effects on the well wall. In the preferred scheme, in the use process, the desolvation is dissolved between the memory plastic polymer and the base pipe to form an annular space, so that the sand-containing fluid primarily filtered by the memory plastic polymer has a larger flow-through space when passing through the slotted base pipe, and the production efficiency is improved. The mode that sets up multistage memory plastics and mesh form screen pipe intercombination along the axial, when can possess the wall of a well support effect, still reduced the use of material, can further practice thrift the cost.

Drawings

The invention will be further explained with reference to the following figures and examples:

fig. 1 is a schematic structural view of the present invention in use.

Fig. 2 is a schematic structural view of another preferred embodiment of the present invention.

Fig. 3 is a schematic structural diagram of another preferred embodiment of the present invention during the process of being lowered to the bottom of the well.

Fig. 4 is a schematic structural diagram in the production process of another preferred embodiment of the present invention.

Fig. 5 is a schematic view of a partial structure of the elastic metal net of the present invention from contraction to expansion.

Fig. 6 is a schematic structural view of the elastic metal net according to the present invention when it contracts.

Fig. 7 is a schematic structural view of the metal supporting net of the present invention.

In the figure: the base pipe 1, memory plastic polymer 2, elastic metal net 3, axial metal wire 31, circumferential metal wire 32, metal support net 4, desolventizing agent 5, well wall 6, porous sieve pipe 7 and netted sieve pipe 8.

Detailed Description

As shown in fig. 1, the expansion screen pipe is provided with a base pipe 1, a memory plastic polymer 2 and an elastic metal net 3 from inside to outside in sequence;

the base pipe 1 is of a hollow structure, and at least the area covered by the memory plastic polymer 2 is provided with a plurality of slots or through holes for liquid to pass through;

the memory plastic polymer 2 is an expandable high polymer material with pores for sand prevention, can be compressed on the ground and expanded under the stimulation of preset conditions after falling to the bottom of a well until contacting with a well wall 6; the outer resilient metal mesh 3 protects the memory plastic polymer 2 from damage during running of the screen. In particular, when passing through the bend, the friction is absorbed by the elastic metal mesh 3 without damaging the memory plastic polymer 2. It is further preferred that the elastic wire netting 3 comprises axial wires and circumferential wires, wherein the axial wires 31 are located adjacent to the outer layer and the circumferential wires 32 are located adjacent to the inner layer. In the compressed state of the memory plastic polymer 2, the circumferential wire obliquely crosses the axis, and in the expanded state of the memory plastic polymer 2, the circumferential wire is approximately perpendicular to the axis. The axial metal wire and the circumferential metal wire are connected in a welding mode, and the welding mode preferably adopts laser welding. The structure has the advantages that the metal wires in the axial direction are located on the outer layer, the metal wires in the circumferential direction are located on the inner layer, and the structure has great advantages when passing through a well wall bending part, such as a part where a vertical well turns to a horizontal well.

The elastic metal net 3 is used for protecting the memory plastic polymer 2 and supporting the well wall 6. According to the structure, the memory plastic polymer 2 is compressed and fixed at the ground surface, and after the memory plastic polymer 2 is put in place underground, the memory plastic polymer 2 is expanded by heating, chemical dissolution, electric heating or the combination of the above modes until the wall of a well is supported.

In a preferred embodiment, the memory plastic polymer 2 is an SMP material.

Shape Memory Polymer, SMP for short), also called Shape Memory Polymer, refers to a Polymer material that can restore the original Shape of a product after changing its original condition and fixing it under certain conditions, and by external stimulation such as heat, electricity, light, chemical induction, etc.

SMPs can be classified into thermotropic SMP, electro SMP, photo SMP, chemical inductive SMP, etc. according to their recovery principles. The shape memory function of the thermotropic SMP is mainly derived from the existence of two incompletely compatible phases in the material, namely a stationary phase for keeping the shape of a formed product and a reversible phase which can be softened and hardened to be reversibly changed along with the change of temperature. The stationary phase acts to memorize and restore the original shape, and the reversible phase ensures that the shaped article can change shape. SMPs can be divided into two broad classes, thermosetting and thermoplastic, depending on the structural characteristics of the stationary phase, in addition to a so-called "cold-formed" shape memory polymer material.

A thermosetting SMP is prepared through heating polymer to smelting point (more than tm, mixing it with cross-linking agent, cross-linking reaction in mould, cooling, crystallizing to obtain initial state, which is the fixed one, reversible one, making it into any shape, cooling, fixing, and shaping the molecular chain to obtain deformed shape, the micro Brownian motion of the reversible phase molecular chain is intensified, while the stationary phase is still in a solidified state, at the moment, the SMP is deformed by a certain external force, the SMP is cooled by keeping the external force, and the reversible phase is solidified to obtain a stable new shape, namely a deformed state. When the temperature is raised to (tg) again, the reversible phase is softened, the fixed phase is kept solidified, the reversible phase molecular chain is reactivated in motion, and the reversible phase molecular chain gradually reaches a thermodynamic equilibrium state under the action of the restoring stress of the fixed phase, namely macroscopically shows a restored state.

The electro SMP is a composite scheme of thermotropic shape memory polymer material and conductive substance, and adopts composite materials such as conductive carbon black, metal powder and conductive polymer. The memory mechanism of the composite material is the same as that of a thermal induction type shape memory polymer, and the composite material enables the temperature of the system to rise through heat generated by current so as to recover the shape, so that the composite material has both conductivity and a good shape memory function.

In a preferred embodiment, the memory plastic polymer 2 is arranged in a heated and compressed shape and gradually expands under the influence of temperature drop after being put into the bottom of the well.

In a preferable scheme, the memory plastic polymer 2 is set into a normal-temperature compression shape, and is gradually expanded after being put into the bottom of a well and heated by electrifying.

In the preferred scheme, the memory plastic polymer 2 is set into a normal-temperature compressed shape, and the shape is recovered after a high-temperature liquid medium is introduced after the memory plastic polymer is put into the bottom of a well.

In the preferred scheme, the memory plastic polymer 2 is set into a normal-temperature compression shape, an adhesive is arranged in the compression process, and the shape of the memory plastic polymer is recovered by introducing a dissolving agent after the memory plastic polymer is put into the bottom of a well. For example, modified starch is used as the binder, and slightly alkaline water is used as the dissolving agent. Or oil-based hot melt adhesive, wherein the dissolving agent is ethanol.

In a preferable scheme, metal supporting nets 4 are arranged at two ends of the elastic metal net 3, and the metal supporting nets 4 are arranged to be capable of swinging along the axial direction;

when the elastic metal net is in a compressed state, the metal support net 4 swings in a direction away from the memory plastic polymer 2, and when the elastic metal net is in an expanded state, the metal support net 4 swings in a direction close to the memory plastic polymer 2.

In a preferred embodiment, as shown in FIG. 2, a desolvation agent 5 is provided between the memory plastic polymer 2 and the substrate tube 1, and the desolvation agent 5 can be desolvated under the action of temperature or a dissolution medium after the memory plastic polymer 2 is expanded. The desolvation agent 5 is preferably paraffin or modified starch, such as acid or alkali sensitive starch, and after the desolvation agent 5 is lowered to the bottom of the well, a corresponding acid or alkali sensitive medium is introduced to dissolve the desolvation agent 5, so that a void space which does not influence the supporting effect is formed. With this configuration, the working medium, such as crude oil or hydrate, can be introduced into the base pipe with a short filtration stroke.

In a preferred scheme, as shown in figures 3 and 4, sections 2 of memory plastic polymer and screen sections are arranged on the surface of a base pipe 1 in an axially staggered mode;

the screen section is provided with a hole-shaped screen pipe 7 and a mesh screen pipe 8. With this structure, the combination of the mesh-type screen pipe 7 and the mesh-type screen pipe 8 can provide high production efficiency while the memory plastic polymer 2 provides a supporting effect.

The above embodiments are merely preferred technical solutions of the present invention, and should not be considered as limitations of the present invention, and the features in the embodiments and the examples in the present application may be arbitrarily combined with each other without conflict. The protection scope of the present invention shall be defined by the claims and the technical solutions described in the claims, including the technical features of the equivalent alternatives as the protection scope. Namely, equivalent alterations and modifications within the scope of the invention are also within the scope of the invention.

Claims (10)

1. An expansion screen pipe is characterized in that: the device is sequentially provided with a base pipe (1), a memory plastic polymer (2) and an elastic metal mesh (3) from inside to outside;

the base pipe (1) is of a hollow structure, and at least the area covered by the memory plastic polymer (2) is provided with a plurality of slots or through holes for liquid to pass through;

the memory plastic polymer (2) is an expandable high polymer material with pores for sand prevention, can be compressed on the ground and expanded under the stimulation of preset conditions after falling to the bottom of a well until contacting with a well wall (6);

the elastic metal net (3) is used for protecting the memory plastic polymer (2) and supporting the well wall (6).

2. The expandable screen as defined in claim 1, wherein: the memory plastic polymer (2) is an SMP material.

3. The expansion screen as recited in claim 2 wherein: the memory plastic polymer (2) is set to a heating compression shape and gradually expands under the influence of temperature reduction after being put at the bottom of a well.

4. The expansion screen as recited in claim 2 wherein: the memory plastic polymer (2) is set into a normal-temperature compressed shape and is gradually opened after being put into the bottom of a well and heated by electrifying.

5. The expansion screen as recited in claim 2 wherein: the memory plastic polymer (2) is set into a normal-temperature compressed shape, and the shape is recovered after a high-temperature liquid medium is introduced after the memory plastic polymer is put into the bottom of a well.

6. The expansion screen as recited in claim 2 wherein: the memory plastic polymer (2) is set into a normal-temperature compression shape, an adhesive is arranged in the compression process, and the shape of the memory plastic polymer is recovered after the memory plastic polymer is put into the bottom of a well and a dissolving agent is introduced.

7. The expansion screen according to any one of claims 1 to 6, wherein: metal supporting nets (4) are arranged at two ends of the elastic metal net (3), and the metal supporting nets (4) are arranged into a structure capable of swinging along the axial direction;

when the elastic metal net is in a compressed state, the metal supporting net (4) swings towards a direction far away from the memory plastic polymer (2), and when the elastic metal net is in an expanded state, the metal supporting net (4) swings towards a direction close to the memory plastic polymer (2).

8. The expandable screen as defined in claim 7, wherein: the elastic metal net (3) is formed by combining axial metal wires (31) and circumferential metal wires (32), wherein the axial metal wires (31) are positioned at the position close to the outer layer, and the circumferential metal wires (32) are positioned at the position close to the inner layer.

9. The expandable screen as defined in claim 1, wherein: a desolvation agent (5) is arranged between the memory plastic polymer (2) and the base pipe (1), and after the memory plastic polymer (2) expands, the desolvation agent (5) can be dissolved under the action of temperature or a dissolving medium.

10. The expandable screen as defined in claim 1, wherein: the surface of the base pipe (1) is provided with memory plastic polymer (2) sections and screen pipe sections in an axially staggered manner;

the screen section is provided with a hole-shaped screen pipe (7) and a mesh screen pipe (8).

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