阅读说明：本技术 一种新式沉砂底筛堵 (New-type sand setting bottom screen is stifled ) 是由 贾贻勇 袁杰 崔洁 田冰 谢文献 徐加军 赵焕伟 杨忠男 胡剑 李莉 于 2020-05-22 设计创作，主要内容包括：本发明公开了一种新式沉砂底筛堵,包括：中心管,所述中心管开设径向贯通的中心管径向通孔；外管,所述外管套装在中心管外部,外管与中心管之间构成环形空间；游动阀,所述游动阀套装在中心管外圆上,与中心管相对轴向滑动,游动阀还开设游动阀径向通孔,中心管径向通孔与游动阀径向通孔为径向连通状态；阀座,所述阀座镶嵌在外管内壁,阀座上端口内壁开设内锥面,所述游动阀下端外壁开设外锥面,游动阀下端的外锥面与阀座上端的内锥面构成密封副。本发明解决了各种原因导致的漏失、工具失效问题,改变内部结构,可以避免异物卡、脱扣等造成的失效,延长分注管柱使用寿命,提高油田注水开发的效益。(The invention discloses a novel sand setting bottom screen plug, which comprises: the central tube is provided with a central tube radial through hole which is radially communicated; the outer pipe is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe; the traveling valve is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state; the valve seat is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair. The invention solves the problems of leakage and tool failure caused by various reasons, changes the internal structure, can avoid the failure caused by foreign matter blocking, tripping and the like, prolongs the service life of the separate injection pipe column and improves the benefit of oilfield flooding development.)

1. The utility model provides a new-type screen plug at bottom of setting sand which characterized in that includes:

the central tube is provided with a central tube radial through hole which is radially communicated;

the outer pipe is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

2. The new-type sand-settling screen plug as claimed in claim 1, wherein the inner wall of the traveling valve is provided with an O-ring for sealing, the inner wall of the traveling valve is in a sealing state with the outer wall of the central pipe, the inner part of the outer pipe is provided with a stepped hole, namely the stepped hole comprises a large-diameter cavity pipe section and a small-diameter cavity pipe section, and the outer diameter of the traveling valve is smaller than the inner diameter of the small-diameter cavity pipe section of the outer pipe.

3. The new screen plug of claim 2 wherein the traveling valve has a top cap at its upper end, the outer diameter of the top cap being the same as the inner diameter of the small diameter tubular section of the outer tube.

4. The new sand screen plug as recited in claim 3 further comprising:

and the spring is sleeved on the excircle of the central tube, and the lower end of the spring abuts against the upper end face of the top cap of the traveling valve.

5. The new sand screen plug as recited in claim 4 further comprising:

the stop collar, the stop collar suit is at the center tube excircle, wholly is located the major diameter chamber pipeline section of outer tube, and the stop collar is inside self with the spring protection, and the stop collar external diameter is greater than outer tube minor diameter chamber pipeline section internal diameter, and the stop collar internal diameter is less than outer tube minor diameter chamber pipeline section internal diameter.

6. The new sand screen plug as claimed in claim 5, wherein the axial distance from the lower end of the stop collar to the upper end of the valve seat is greater than the axial length of the traveling valve.

7. The new-type sand-settling bottom screen plug as claimed in claim 4, 5 or 6, wherein the upper end of the outer pipe is screwed with the upper joint, the upper end of the central pipe is inserted into the inner hole of the central pipe, the outer diameter of the upper end of the central pipe is consistent with the inner diameter of the inner hole of the upper joint, and the upper end of the spring is pressed against the lower end face of the upper joint.

8. A new sand screen plug according to claim 4, 5 or 6, characterized in that the lower end of the outer pipe is screwed with the outer wall of the lower joint, and the lower end of the central pipe is screwed with the inner hole of the lower joint.

9. The new screen plug as claimed in claim 8, wherein the lower sub is internally provided with a stepped hole, the upper end of the stepped hole is communicated with the lower end of the traveling valve, the lower sub is provided with a lower sub radial through hole, and the lower sub radial through hole is communicated with the stepped hole inside the lower sub.

10. The new-type sand setting bottom screen plug according to claim 9, characterized in that the valve seat is of an annular structure, the inner diameter of the valve seat is larger than the outer diameter of the central pipe, the upper end surface of the valve seat is limited by the limiting table on the inner wall of the outer pipe, and the lower end surface of the valve seat is limited by the upper end surface of the lower connector.

Technical Field

The invention relates to the technical field of oilfield separate-layer water injection, in particular to a novel sand setting bottom screen plug.

Background

The sand setting bottom screen plug is an important component tool of a separate-layer water injection pipe column, and the tool has two main functions: firstly, in the water injection process, the effects of sealing the pipe column and opening the water distributor are achieved; secondly, in the well washing process, the circulation of well washing water from the casing to the oil pipe is realized; thirdly, sand and scale in the pipe column fall into a sand setting tail pipe through a sand setting channel.

The tool is widely applied to oil field development, but in the application process, mechanical impurities are filled between the ball and the ball seat to cause leakage, the ball is impacted with the sand blocking cap to cause tripping, the ball and the ball seat are corroded and scaled to cause leakage and other problems, the water injection amount is completely blocked from the bottom screen, layered water injection cannot be realized, and the effective period of a separate injection pipe column in a well is short.

CN 200820016175.1 discloses a compound sand setting check valve used in the petroleum industry, which is suitable for an oil production well of an electric submersible pump. The device comprises an upper joint, a primary sand setting mechanism and a secondary sand setting mechanism, wherein the primary sand setting mechanism and the secondary sand setting mechanism are connected together by a central pipe jacket to form two sand setting cavities, so that the sand setting effect is improved. After sand blocking and sand setting of the two sets of sand setting mechanisms, the sand carrying amount in oil is greatly reduced, the damage of gravel to the electric submersible pump is reduced, the service life of the electric submersible pump is prolonged, the pump inspection operation period of an oil production well of the electric submersible pump is prolonged, and the economic benefit is improved.

The tool is widely applied to oil field development, but mechanical impurity cushion is generated in the application process to cause leakage between the ball and the ball seat, the ball impacts a sand blocking cap to cause tripping, the ball and the ball seat are corroded and scaled to cause leakage and other problems, and the effective period of the separate injection pipe column in a well is short.

Compared with a comparison document CN 200820016175.1, the invention has the following 2 different points and technical advantages: 1. the invention is suitable for high-pressure water injection wells with different well conditions; 2. the invention has different principles and functions, and realizes the functions of sealing the pipe column, washing the well and settling sand. The sand setting bottom screen plug is an important component tool of a separate-layer water injection pipe column, and the tool has two main functions: firstly, in the water injection process, the effects of sealing the pipe column and opening the water distributor are achieved; secondly, in the well washing process, the circulation of well washing water from the casing to the oil pipe is realized; thirdly, sand and scale in the pipe column fall into a sand setting tail pipe through a sand setting channel.

CN 201520917681.8 discloses a sand setting check valve at the bottom of a water injection string, which comprises a sleeve, a check valve set, a runner joint, an angle pipe and a sand setting tail pipe, wherein the check valve set is connected at the bottom of the water injection string, when the sand setting in the water injection string falls, the sand setting is sunk into the sand setting tail pipe through a lower crescent channel and an upper crescent channel and cannot be accumulated on the check valve set, the axis of the angle pipe is not coaxial with the axis of the runner joint, the distance between the two axes is 4-19m, the angle pipe is arranged at one side inside the runner joint, the lower crescent channel and the upper crescent channel are more concentrated than the runner when the angle pipe is in the middle position, no blockage is caused to sand, the sunk sand can smoothly sink into the sand setting at the lower part, the check valve is ensured not to be buried by sand, when the well is washed, a valve ball can be washed away by well washing water, the invention can smoothly wash the well and ensure that the water injection well can normally inject water for a long time, has obvious economic benefit.

The tool is widely applied to oil field development, but mechanical impurity cushion is generated in the application process to cause leakage between the ball and the ball seat, the ball impacts a sand blocking cap to cause tripping, the ball and the ball seat are corroded and scaled to cause leakage and other problems, and the effective period of the separate injection pipe column in a well is short.

Compared with a comparison document CN 201520917681.8, the invention has the following 2 different points and technical advantages: 1. the working principle is different, and the invention works more reliably. 2. The structure is simpler. The manufacture and processing are simple and convenient, the number of accessories is small, and the service life is long. The sand setting bottom screen plug is an important component tool of a separate-layer water injection pipe column, and the tool has two main functions: firstly, in the water injection process, the effects of sealing the pipe column and opening the water distributor are achieved; secondly, in the well washing process, the circulation of well washing water from the casing to the oil pipe is realized; thirdly, sand and scale in the pipe column fall into a sand setting tail pipe through a sand setting channel.

2016.12, the university of Yangtze river school newspaper (from the department), the improvement research of winning the oil field sand setting bottom screen plug of lump, to the long-term water injection of dividing the injection well lead to the sand setting bottom screen plug inside corrode the scale deposit lose, and the repeated well-flushing lead to the sand setting bottom screen plug inside block up the problem that the well-flushing is unable, found out the main influence factor that leads to the sand setting bottom screen plug to lose efficacy. Aiming at the problems of the sand setting type bottom screen blockage, the bottom screen blockage is improved, firstly, a sand setting channel is changed into ring cutting from 10 holes, and the flow area is increased by 43 percent; secondly, different materials are selected, the corrosion resistance and the price are compared, the improved material is determined to be stainless steel, and the ball seat is changed from an integrated type to a split type; and thirdly, the material of the ball claw is improved, the periphery is strengthened and the sealing performance is enhanced, and the phenomenon that the spring is clamped or the valve ball pad is broken due to the accumulation of settled sand is avoided. The ball claw for supporting the valve ball and the periphery of the spring are fixed by metal rings and sealed by rubber rings, so that the phenomenon that the spring is clamped or the valve ball pad is broken due to accumulation of settled sand is avoided.

The tool is widely applied to oil field development, but mechanical impurity cushion is generated in the application process to cause leakage between the ball and the ball seat, the ball impacts a sand blocking cap to cause tripping, the ball and the ball seat are corroded and scaled to cause leakage and other problems, and the effective period of the separate injection pipe column in a well is short.

Compared with the comparison file, the invention has the following 2 different points and technical advantages: 1. the working principle is different, and the invention works more reliably. 2. The structure is simpler, the internal components are removed, and the sand setting channel is larger. The sand setting bottom screen plug is an important component tool of a separate-layer water injection pipe column, and the tool has two main functions: firstly, in the water injection process, the effects of sealing the pipe column and opening the water distributor are achieved; secondly, in the well washing process, the circulation of well washing water from the casing to the oil pipe is realized; thirdly, sand and scale in the pipe column fall into a sand setting tail pipe through a sand setting channel.

The technical scheme of the disclosed technology, the technical problems to be solved and the beneficial effects are all different from the technical scheme of the invention, or the technical field or the application occasion is different, and no technical inspiration exists in the technical scheme disclosed above.

Disclosure of Invention

The invention aims to provide a novel sand setting bottom screen plug aiming at the defects in the prior art, solves the problems of leakage and tool failure caused by various reasons, changes the internal structure, can avoid failure caused by foreign matter clamping, tripping and the like, prolongs the service life of a separate injection string, and improves the benefit of oilfield flooding development.

In order to achieve the purpose, the invention adopts the following technical scheme:

a new sand screen plug comprising:

the central tube is provided with a central tube radial through hole which is radially communicated;

the outer pipe is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

Furthermore, the O-shaped ring for sealing is arranged on the inner wall of the traveling valve, the inner wall of the traveling valve and the outer wall of the central pipe are in a sealing state, the inner part of the outer pipe is provided with a stepped hole, namely the outer pipe comprises a large-diameter cavity pipe section and a small-diameter cavity pipe section, and the outer diameter of the traveling valve is smaller than the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Furthermore, the upper end of the traveling valve is provided with a top cap, and the outer diameter of the top cap is consistent with the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Further, still include:

and the spring is sleeved on the excircle of the central tube, and the lower end of the spring abuts against the upper end face of the top cap of the traveling valve.

Further, still include:

the stop collar, the stop collar suit is at the center tube excircle, wholly is located the major diameter chamber pipeline section of outer tube, and the stop collar is inside self with the spring protection, and the stop collar external diameter is greater than outer tube minor diameter chamber pipeline section internal diameter, and the stop collar internal diameter is less than outer tube minor diameter chamber pipeline section internal diameter.

Further, the axial distance from the lower end of the limiting sleeve to the upper end of the valve seat is larger than the axial length of the traveling valve.

Furthermore, the upper end of the outer pipe is connected with the upper joint in a threaded manner, the upper end of the central pipe is inserted into the inner hole of the central pipe, the outer diameter of the upper end of the central pipe is consistent with the inner diameter of the inner hole of the upper joint, and the upper end of the spring abuts against the lower end face of the upper joint.

Further, the outer wall of the lower connector is connected with the lower end of the outer pipe in a threaded mode, and the inner hole of the lower connector is connected with the lower end of the central pipe in a threaded mode.

Furthermore, a stepped hole is formed in the lower joint, the upper end of the stepped hole is communicated to the lower end of the traveling valve, a lower joint radial through hole is formed in the lower joint, and the lower joint radial through hole is communicated with the stepped hole in the lower joint.

Furthermore, the valve seat is of an annular structure, the inner diameter of the valve seat is larger than the outer diameter of the central pipe, the upper end face of the valve seat is limited by the limiting table on the inner wall of the outer pipe, and the lower end face of the valve seat is limited by the upper end face of the lower connector.

Compared with the prior art, the invention has the following beneficial effects:

when water is injected, the traveling valve and the valve seat are in a sealed state by means of water injection pressure and a spring in the pipe column, and a channel between the annular space of the oil sleeve and the inner cavity of the pipe column is isolated; when the well is reversely washed, the flushing fluid pushes the floating valve to compress the spring through the radial through hole and the annular flow passage so that the floating valve opens the flushing channel upwards, then flows into the annular flow passage, enters the inner hole of the central tube through the radial through hole and flows out of the ground through the tubular column. The structure and the process have no technical problems of leakage or tripping caused by foreign matter clamping, so the invention can avoid the failure problem caused by foreign matter clamping, tripping and the like in the prior art, change the structure of the sand setting bottom screen plug, eliminate tool failure points, increase the area of a sand setting passage, prolong the service life of a separate injection pipe column and improve the benefit of oilfield water injection development.

Drawings

Fig. 1 is a schematic structural diagram of a novel sand setting bottom screen plug of the invention.

In the figure: 1-upper connector, 2-outer tube, 3-O-shaped ring, 4-limiting sleeve, 5-central tube, 6-spring, 7-floating valve, 8-radial through hole, 9-radial through hole, 10-annular flow channel, 11-O-shaped ring, 12-valve seat, 13-O-shaped ring, 14-annular flow channel, 15-radial through hole, 16-lower connector and 17-O-shaped ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

referring to fig. 1, the present invention provides a technical solution:

a new sand screen plug comprising:

the central tube 5 is provided with a central tube radial through hole which is radially communicated;

the outer pipe 2 is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve 7 is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat 12 is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

Furthermore, the O-shaped ring for sealing is arranged on the inner wall of the traveling valve, the inner wall of the traveling valve and the outer wall of the central pipe are in a sealing state, the inner part of the outer pipe is provided with a stepped hole, namely the outer pipe comprises a large-diameter cavity pipe section and a small-diameter cavity pipe section, and the outer diameter of the traveling valve is smaller than the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Furthermore, the upper end of the traveling valve is provided with a top cap, and the outer diameter of the top cap is consistent with the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Further, still include:

and the spring 6 is sleeved on the outer circle of the central pipe, and the lower end of the spring abuts against the upper end face of the top cap of the traveling valve.

Further, still include:

and the limiting sleeve 4 is sleeved on the outer circle of the central tube, is integrally positioned in the large-diameter cavity tube section of the outer tube, protects the spring inside the limiting sleeve, has an outer diameter larger than the inner diameter of the small-diameter cavity tube section of the outer tube, and has an inner diameter smaller than the inner diameter of the small-diameter cavity tube section of the outer tube.

Further, the axial distance from the lower end of the limiting sleeve to the upper end of the valve seat is larger than the axial length of the traveling valve.

Furthermore, the upper end of the outer pipe is connected with the upper joint 1 in a threaded manner, the upper end of the central pipe is inserted into the inner hole of the central pipe, the outer diameter of the upper end of the central pipe is consistent with the inner diameter of the inner hole of the upper joint, and the upper end of the spring abuts against the lower end face of the upper joint.

Further, the outer wall of the lower joint 16 is connected with the lower end of the outer pipe in a threaded mode, and the inner hole of the lower joint is connected with the lower end of the central pipe in a threaded mode.

Furthermore, a stepped hole is formed in the lower joint, the upper end of the annular flow channel 14 serving as the stepped hole is communicated to the lower end of the traveling valve, a radial through hole of the lower joint is formed in the lower joint, and the radial through hole of the lower joint is communicated with the stepped hole in the lower joint.

Furthermore, the valve seat is of an annular structure, the inner diameter of the valve seat is larger than the outer diameter of the central pipe, the upper end face of the valve seat is limited by the limiting table on the inner wall of the outer pipe, and the lower end face of the valve seat is limited by the upper end face of the lower connector.

The upper end of the upper joint 1 is in threaded connection with the upper end of the outer pipe 2, the lower end of the outer pipe 2 is in threaded connection with the lower joint 16, the upper end of the central pipe 5 is inserted into an inner hole of the upper joint 1, the lower end of the central pipe is in threaded connection with the lower joint 16, the limiting sleeve 4, the spring 6 and the movable valve 7 are respectively sleeved on an excircle on the upper portion of the central pipe 5, the valve seat 12 is embedded in an inner hole in the lower end portion of the outer pipe 2, an outer conical surface at the lower end of the movable valve 7 and an inner conical surface at the upper end of the valve seat 12 form a sealing pair, a group of radial through holes 9 are formed in the middle upper portion of the central pipe 5, a group of radial through holes 8 are formed in the movable valve 7, and an inner step hole in the upper portion of the lower joint 16 is communicated with a group of radial through holes 15.

The working principle is that the traveling valve 7 and the valve seat 12 are in a sealing state by means of water injection pressure in the pipe column and the spring 6 during water injection, and a channel between the oil sleeve annulus and the pipe column inner cavity is isolated; when the well is reversely washed, the flushing fluid pushes the traveling valve 7 to compress the spring 6 through the radial through hole 15 and the annular flow passage 14 so as to open the flushing channel upwards, then flows into the annular channel 10, enters the inner hole of the central tube 5 through the radial through holes 8 and 9 and flows out of the ground through the tubular column. The structure and the process have no technical problems of leakage or tripping caused by foreign matter clamping, so the invention can avoid the failure problem caused by foreign matter clamping, tripping and the like in the prior art, change the structure of the sand setting bottom screen plug, eliminate tool failure points, increase the area of a sand setting passage, prolong the service life of a separate injection pipe column and improve the benefit of oilfield water injection development.

Example 2:

referring to fig. 1, the present invention provides a technical solution:

a new sand screen plug comprising:

the central tube 5 is provided with a central tube radial through hole which is radially communicated;

the outer pipe 2 is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve 7 is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat 12 is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

Furthermore, the O-shaped ring for sealing is arranged on the inner wall of the traveling valve, the inner wall of the traveling valve and the outer wall of the central pipe are in a sealing state, the inner part of the outer pipe is provided with a stepped hole, namely the outer pipe comprises a large-diameter cavity pipe section and a small-diameter cavity pipe section, and the outer diameter of the traveling valve is smaller than the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Furthermore, the upper end of the traveling valve is provided with a top cap, and the outer diameter of the top cap is consistent with the inner diameter of the small-diameter cavity pipe section of the outer pipe. Prevent that impurity from getting into the stop collar inside of travelling valve top.

Further, still include:

and the spring 6 is sleeved on the outer circle of the central pipe, and the lower end of the spring abuts against the upper end face of the top cap of the traveling valve.

Further, still include:

and the limiting sleeve 4 is sleeved on the outer circle of the central tube, is integrally positioned in the large-diameter cavity tube section of the outer tube, protects the spring inside the limiting sleeve, has an outer diameter larger than the inner diameter of the small-diameter cavity tube section of the outer tube, and has an inner diameter smaller than the inner diameter of the small-diameter cavity tube section of the outer tube.

Further, the axial distance from the lower end of the limiting sleeve to the upper end of the valve seat is larger than the axial length of the traveling valve.

Furthermore, the upper end of the outer pipe is connected with the upper joint 1 in a threaded manner, the upper end of the central pipe is inserted into the inner hole of the central pipe, the outer diameter of the upper end of the central pipe is consistent with the inner diameter of the inner hole of the upper joint, and the upper end of the spring abuts against the lower end face of the upper joint.

Example 3:

referring to fig. 1, the present invention provides a technical solution:

a new sand screen plug comprising:

the central tube 5 is provided with a central tube radial through hole which is radially communicated;

the outer pipe 2 is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve 7 is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat 12 is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

Furthermore, the O-shaped ring for sealing is arranged on the inner wall of the traveling valve, the inner wall of the traveling valve and the outer wall of the central pipe are in a sealing state, the inner part of the outer pipe is provided with a stepped hole, namely the outer pipe comprises a large-diameter cavity pipe section and a small-diameter cavity pipe section, and the outer diameter of the traveling valve is smaller than the inner diameter of the small-diameter cavity pipe section of the outer pipe.

Example 4:

referring to fig. 1, the present invention provides a technical solution:

a new sand screen plug comprising:

the central tube 5 is provided with a central tube radial through hole which is radially communicated;

the outer pipe 2 is sleeved outside the central pipe, and an annular space is formed between the outer pipe and the central pipe;

the traveling valve 7 is sleeved on the outer circle of the central pipe and axially slides relative to the central pipe, a radial through hole of the traveling valve is formed in the traveling valve, and the radial through hole of the central pipe and the radial through hole of the traveling valve are in a radial communication state;

the valve seat 12 is embedded in the inner wall of the outer pipe, an inner conical surface is arranged on the inner wall of the upper port of the valve seat, an outer conical surface is arranged on the outer wall of the lower end of the traveling valve, and the outer conical surface of the lower end of the traveling valve and the inner conical surface of the upper end of the valve seat form a sealing pair.

Although fig. 1 is used for all the above embodiments, it is obvious to those skilled in the art that a separate drawing is not shown as long as the parts or structural features missing in the embodiments are removed from the drawing. As will be clear to the skilled person. Of course, the embodiments with more components are only the best embodiments, and the embodiments with less components are the basic embodiments, but the basic objects of the invention can also be achieved, so all of them are within the protection scope of the invention.

All parts and parts which are not discussed in the present application and the connection mode of all parts and parts in the present application belong to the known technology in the technical field, and are not described again. Such as welding, threaded connections, etc.

In the present invention, the term "plurality" means two or more unless explicitly defined otherwise. The terms "mounted," "connected," "fixed," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; "coupled" may be direct or indirect through an intermediary. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "front", "rear", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or unit must have a specific direction, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description herein, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.