CN214366677U

CN214366677U - Valve structure and oil-well pump

Info

Publication number: CN214366677U
Application number: CN202120103108.9U
Authority: CN
Inventors: 卫玮
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-14
Filing date: 2021-01-14
Publication date: 2021-10-08
Anticipated expiration: 2031-01-14

Abstract

The utility model relates to an oil development technical field provides a valve structure and oil-well pump. The valve structure comprises a valve cover with a first end and a second end which are communicated, wherein a fixing part is arranged in the second end, and an oil passing hole is arranged on the fixing part; the valve seat has a bottom end part and a top end part which are communicated, and the top end part is matched in the first end; the blocking piece is arranged in the valve cover, is a rotary body and comprises a bottom surface and a side surface, the side surface gradually shrinks towards the first end and is rotatably abutted with the top end part, and the bottom surface is larger than the inner diameter of the top end part and faces towards the second end; the sealing element is arranged on one side of the blocking element close to the second end, the edge of the sealing element is provided with a flanging which is abutted against the top end part, and the sealing element is made of elastic material; the guide assembly comprises a guide post with one end connected with the plugging piece and extends to the second end along the axial direction of the valve cover; the guide plate is connected to the other end of the guide post, is slidably arranged in the valve cover, and is provided with an oil through hole. The valve structure will not be locked.

Description

Valve structure and oil-well pump

Technical Field

The utility model relates to an oil development technical field especially relates to a valve structure and oil-well pump including this valve structure.

Background

In the field of oil extraction, an oil well pump is an indispensable device that can lift crude oil in a well to the surface. The existing oil well pump generally adopts a valve to realize the one-way flow of petroleum, and the valve is a valve. Existing valves are typically opened and closed by contact or separation of a closure piece from the valve seat. However, the existing guide post is easy to be stuck, so that the valve structure is damaged; therefore, the oil well pump must stop working to replace the valve structure, and the oil extraction efficiency is affected.

The above information disclosed in the background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute prior art that is known to a person of ordinary skill in the art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome above-mentioned prior art's the easy dead not enough of card of guide post, provide a guide post is difficult to card dead valve structure and the oil-well pump including this valve structure.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

According to one aspect of the present disclosure, there is provided a valve structure comprising:

the valve cover is provided with a first end and a second end which are communicated, a fixing part is arranged in the second end, and an oil passing hole which is communicated along the axial direction of the valve cover is arranged on the fixing part;

a valve seat having a bottom end portion and a top end portion therethrough, the top end portion being sealingly engaged within the first end, the bottom end portion being located outside the first end;

the blocking piece is a rotary body and comprises a bottom surface and a side surface surrounding the bottom surface, the side surface gradually shrinks towards the first end and is rotatably abutted with the top end part of the valve seat, and the bottom surface is larger than the inner diameter of the top end part and faces towards the second end;

the sealing element is covered on one side of the blocking element close to the second end, a flange which surrounds the blocking element and abuts against the top end portion is arranged on the edge of the sealing element, and the sealing element is made of elastic materials;

one end of the guide assembly is connected with the plugging piece, the guide assembly comprises a guide column and a guide plate, and one end of the guide column is connected with the plugging piece and extends to the second end along the axial direction of the valve cover; the guide plate is connected to the other end of the guide column, the guide plate is slidably arranged in the valve cover, and the guide plate is provided with an oil through hole.

In an exemplary embodiment of the present disclosure, the guide assembly further includes:

and the extension plate is arranged on the periphery of the guide plate and extends along the axial direction of the valve cover.

In an exemplary embodiment of the present disclosure, the guide post includes:

a post having one end connected to the blocking member and extending axially of the valve cover toward the second end;

the sleeve is fixedly sleeved outside the column body, one end of the sleeve is abutted to the sealing element, and the other opposite end of the sleeve is connected with the guide plate.

In an exemplary embodiment of the present disclosure, a side of an end portion of the sleeve abutting the seal is gradually contracted toward the second end.

In an exemplary embodiment of the disclosure, the side surface of the sealing member is gradually contracted toward the second end, and the area and the shape of two contact surfaces of the sleeve and the sealing member contacting each other are the same.

In an exemplary embodiment of the disclosure, a surface of the cuff abutting the tip portion has at least one ring of annular ridge surrounding the closure.

In an exemplary embodiment of the present disclosure, a surface of the annular projected ridge abutting against the tip portion is a curved surface.

In an exemplary embodiment of the present disclosure, the valve structure further includes:

and the sealing ring is arranged between the valve seat and the valve cover.

In an exemplary embodiment of the present disclosure, the blocking member is a segment structure, the bottom surface is a bottom surface of the segment structure, and the side surface is a spherical cap of the segment structure.

According to one aspect of the present disclosure, there is provided an oil well pump comprising:

the pump cylinder is provided with a penetrating oil inlet end and a penetrating oil outlet end;

the plunger is slidably arranged in the pump cylinder;

the valve structure is arranged in the pump barrel, and the second end of the valve cover of the valve structure is fixedly butted with the oil inlet end of the pump barrel along the axial direction.

According to the above technical scheme, the utility model discloses possess at least one in following advantage and the positive effect:

the valve structure of the utility model realizes sealing by the butt joint of the plugging piece and the top end part of the valve seat; simultaneously, because the one side that is close to the second end of shutoff piece has set up the sealing member of elastic material, under the effect of oil pressure, the turn-ups of sealing member can cooperate with the end face seal of this top portion to realize twice and seal, make sealed effect promote. In addition, because the guide assembly is including connecting in the guide post of shutoff piece and connecting in the deflector of the relative other end of guide post, the deflector slidable is located in the valve cover, realizes the direction through the deflector along the axial removal of valve cover, passes the through-hole realization direction on the fixed part of valve cover through the guide post slidable among the prior art, the dead phenomenon of card owing to the slope of guide post appears in the length of the guide post in this application is short difficult to.

Drawings

The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

FIG. 1 is a schematic diagram of an exemplary embodiment of a valve structure of the present invention;

FIG. 2 is a schematic view of the construction of the closure of FIG. 1;

FIG. 3 is a schematic view of the seal of FIG. 1;

fig. 4 is a schematic structural diagram of an example embodiment of the oil pump of the present invention.

The reference numerals of the main elements in the figures are explained as follows:

1. a valve cover; 11. a fixed part; 111. an oil passing hole; 12. a first boss;

2. a valve seat; 21. a first seat body; 22. a second seat body; 221. a second boss;

3. a blocking member; 31. a bottom surface; 32. a side surface;

4. a seal member; 41. flanging; 411. an annular rib;

5. a guide assembly; 51. a guide post; 511. a cylinder; 512. a sleeve; 52. a guide plate; 53. an extension plate; 54. an oil through hole;

6. a seal ring;

100. a valve structure; 200. a pump barrel.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

The present example embodiment first provides a valve structure, which, as shown with reference to fig. 1, 2 and 3, may include a valve cover 1, a valve seat 2, a blocking member 3, a sealing member 4 and a guide assembly 5; the valve cover 1 is provided with a first end and a second end which are communicated, a fixing part 11 is arranged in the second end, and an oil passing hole 111 which is communicated along the axial direction of the valve cover 1 is arranged on the fixing part 11; the valve seat 2 has a bottom end portion and a top end portion which are penetrated, the top end portion is in sealed fit with the first end, and the bottom end portion is positioned outside the first end; the plugging piece 3 is arranged in the valve cover 1, the plugging piece 3 is a rotary body and comprises a bottom surface 31 and a side surface 32 surrounding the bottom surface 31, the side surface 32 gradually shrinks towards the first end and is rotatably abutted with the top end part of the valve seat 2, and the bottom surface 31 is larger than the inner diameter of the top end part and faces towards the second end; the sealing element 4 is covered on one side of the blocking element 3 close to the second end, the edge of the sealing element 4 is provided with a flange 41 which surrounds the blocking element 3 and is abutted against the top end part, and the sealing element 4 is made of elastic material; one end of a guide assembly 5 is connected with the sealing element 4, the guide assembly 5 comprises a guide column 51 and a guide plate 52, one end of the guide column 51 is connected with the blocking element 3 and extends towards the second end along the axial direction of the valve cover 1; the guide plate 52 is connected to the opposite end of the guide post 51, the guide plate 52 is slidably disposed in the valve cover 1, and the guide plate 52 is provided with an oil hole 54.

Sealing is realized by the abutting of the plugging piece 3 and the top end part of the valve seat 2; simultaneously, because the one side that is close to the second end of shutoff piece 3 has set up elastic material's sealing member 4, under the effect of oil pressure, the turn-ups 41 of sealing member 4 can cooperate with the end face seal of this top portion to realize twice and seal, make sealed effect promote. Furthermore, since the guiding assembly 5 comprises the guiding post 51 connected to the blocking piece 3 and the guiding plate 52 connected to the opposite end of the guiding post 51, the guiding plate 52 is slidably disposed in the valve housing 1, guiding is realized by the movement of the guiding plate 52 along the axial direction of the valve housing 1, and compared with the prior art in which guiding is realized by the guiding post 51 slidably passing through the through hole on the fixing part 11 of the valve housing 1, the guiding post 51 in the present application has a shorter length and is less prone to being jammed due to the inclination of the guiding post 51.

In the exemplary embodiment shown in fig. 1, the valve cover 1 may be a cylindrical structure with two ends penetrating, one end of which is a first end and the other end of which is a second end. The cross section of the valve cover 1 may be circular, but may also be oval, rectangular, etc., and is not limited herein.

The fixing portion 11 is disposed in the second end, and the fixing portion 11 can be connected to the inner wall of the second end of the valve cover 1 in a sealing manner, for example, by screwing, or the like, or can be integrally formed with the valve cover 1, which is not limited herein. The fixing portion 11 is provided with an oil passing hole 111 that passes through the valve cover 1 in the axial direction. The oil passing holes 111 may be located at the periphery of the fixing portion 11, and the number of the oil passing holes 111 may be multiple, for example, three, four, five, etc., and each of the oil passing holes 111 may be uniformly distributed around the center of the fixing portion 11.

As shown in fig. 1, the valve seat 2 may have a bottom end portion and a top end portion, and the bottom end portion and the top end portion are communicated through a passage. The top end of the valve seat 2 can extend into the second end of the valve cover 1 and can be in sealing engagement with the inner wall of the valve cover 1, for example, the top end can be screwed with the inner wall of the valve cover 1. Meanwhile, in order to limit the position of the valve cover 1 and the valve seat 2 conveniently, the inner wall of the valve cover 1 is provided with a first boss 12, the outer peripheral surface of the valve seat 2 is provided with a second boss 221 in the area outside the valve cover 1, the top end of the valve seat 2 is abutted against the first boss 12, and the first end of the valve cover 1 is abutted against the second boss 221.

The valve seat 2 can be formed by butt joint of a plurality of seat bodies which are axially distributed, and each seat body is communicated. For example, as shown in fig. 1, the valve seat 2 may include a first seat body 21 and a second seat body 22, wherein:

the first seat 21 and the second seat 22 may be both cylindrical structures with two ends penetrating, but the inner diameters of the two seats may be different. The first seat body 21 is located in the valve cover 1, one end of the second seat body 22 is abutted against the first seat body 21, and the other end of the second seat body extends out of the valve cover 1 from the first end of the valve cover 1. One end of the first seat 21 far away from the second seat 22 belongs to the top end of the valve seat 2, and one end of the second seat 22 far away from the first seat 21 belongs to the bottom end of the valve seat 2.

An annular groove is formed in the periphery of the first seat body 21, the axial section of the annular groove can be rectangular, a sealing ring 6 is arranged in the annular groove, and the sealing ring 6 seals a gap between the first seat body 21 and the valve cover 1.

With reference to fig. 1 and fig. 2, the blocking member 3 is disposed in the valve cover 1, the blocking member 3 is a revolving body and includes a bottom surface 31 and a side surface 32 surrounding the bottom surface 31, the side surface 32 gradually shrinks toward a first end and rotatably abuts against a top end portion of the valve seat 2, and the bottom surface 31 is larger than an inner diameter of the top end portion and faces toward a second end. Specifically, the plugging member 3 has a segment structure, the bottom surface 31 of the plugging member 3 has a segment structure, and the side surface 32 of the plugging member 3 has a segment structure. The spherical cap of the spherical segment structure is rotatably abutted with the top end part of the valve seat 2. The block piece 33 may have other shapes, such as a conical structure, in which the bottom surface 31 of the conical structure is the bottom surface 31 of the block piece 33 and the tapered surface of the cylindrical structure is the side surface 32.

With continued reference to fig. 1 and fig. 3, the sealing element 4 is covered on one side of the blocking element 3 near the second end, and the edge of the sealing element 4 has a flange 41 surrounding the blocking element 3 and abutting against the top end. The sealing member 4 is made of an elastic material, such as rubber. The sealing element 4 is provided with a through hole, the diameter of the through hole is slightly smaller than that of the guide column 51, so that the guide column 51 is tightly combined with the sealing element 4, the sealing element 4 and the plugging element 3 can rotate together, part of the plugging element 3 is positioned in the blind hole, and the sealing element 4 is covered on one side of the plugging element 3 close to the second end. The edge of the sealing element 4 is provided with a flange 41 extending towards the valve seat 2, the flange 41 can be in an annular structure and surrounds the sealing element 3, the flange 41 abuts against the top end part of the valve seat 2, sealing matching is achieved, and sealing is further performed on the basis that the sealing element 3 and the valve seat 2 are sealed.

In order to improve the sealing effect and facilitate the contact between the flange 41 and the end face of the top end of the valve seat 2, the surface of the flange 41 near the top end of the valve seat 2 may have an annular rib 411, and the annular rib 411 surrounds the outer side of the blocking piece 3. The cross section of the annular protruding rib 411 may be arc-shaped, that is, the surface of the annular protruding rib 411 abutting against the top end portion is arc-shaped, or the cross section of the annular protruding rib 411 may be rectangular or other figures. In order to improve the sealing effect, the number of the annular ribs 411 may be plural, and concentrically disposed around the block piece 3, thereby forming a plurality of seals to further prevent oil leakage.

When the sealing member 4 is pressed toward the valve seat 2, the annular rib 411 can be tightly fitted to the end surface of the top end portion of the valve seat 2, and at this time, the annular rib 411 can prevent oil leakage even when the block piece 3 and the valve seat 2 have a gap. When the plugging piece 3 is pressed towards the second end of the valve cover 1, the sealing piece 4 can be driven to synchronously move towards the second end, and the plugging piece 3 and the annular convex rib 411 are separated from the valve seat 2, so that petroleum can enter.

In order to avoid deflection of the block piece 3 and the sealing element 4 during the displacement. In the present exemplary embodiment, a guiding assembly 5 is further provided, the guiding assembly 5 may include a guiding post 51, a guiding plate 52 and an extending plate 53, one end of the guiding post 51 is connected with the blocking piece 3 and extends to the second end along the axial direction of the valve cover 1; the guide plate 52 is connected to the opposite end of the guide post 51, the guide plate 52 is slidably provided in the valve cover 1, and the guide plate 52 is provided with an oil passage hole 54.

The guide post 51 may include a post 511 and a sleeve 512. One end of the column 511 is connected to the bottom surface 31 of the segment structure, the extending direction of the column 511 is the same as the axial direction of the valve cover 1, and the column 511 extends towards the second end of the valve cover 1. The cylinder 511 and the blocking piece 3 may be of one-piece construction, i.e. the cylinder 511 and the blocking piece 3 may be integrally formed. It may also be that the bottom surface 31 of the blocking piece 3 is provided with a connecting rod, one end of the cylinder 511 close to the blocking piece 3 is provided with an axially extending connecting hole, which may be a blind hole, and the connecting rod extends into the connecting hole and is in threaded connection with the connecting hole, thereby detachably connecting the cylinder 511 and the blocking piece 3. Of course, an axially extending connection hole may be provided in the block, and the column 511 may also be directly inserted into the connection hole of the block 3 and threadedly connected to the connection hole.

The sleeve 512 is fixedly sleeved outside the column 511, one end of the sleeve 512 is abutted against the sealing element 4, and the other opposite end is connected with the guide plate 52. The inner cylindrical surface of the sleeve 512 can be provided with internal threads, the cylinder 511 is provided with external threads, and the internal threads of the sleeve 512 are matched with the external threads of the cylinder 511 to fixedly connect the sleeve 512 with the cylinder 511.

The sleeve 512 may be attached to a central location of the guide plate 52. The guide plate 52 is provided with a plurality of oil holes 54, for example, three, four, five, etc., the oil holes 54 are provided, and the oil holes 54 are uniformly distributed around the guide post 51, so that the oil can flow toward the fixing portion 11 side through the oil holes 54. The diameter of the guide plate 52 is slightly smaller than the inner diameter of the valve cover 1, so that the guide plate 52 can reciprocate along the inner wall of the valve cover 1, thereby guiding the movement of the plugging piece 3 and the sealing piece 4, guiding the plugging piece 3 to move along the axial direction of the valve cover 1, and preventing the plugging piece 3 from deflecting in the moving process and being incapable of being in sealing contact with the valve seat 2.

Furthermore, an extension plate 53 may be further provided at the periphery of the guide plate 52, the extension plate 53 extends along the axial direction of the valve cover 1, and the extension plate 53 increases the axial length of the guide assembly 5, so as to provide a more stable guide for the movement of the blocking member 3 and the sealing member 4.

In order to facilitate the flow of oil, the side surface of the end portion of the sleeve 512 abutting the seal 4 is formed in a shape gradually narrowing toward the second end, that is, the side surface of the end portion of the sleeve 512 abutting the seal 4 is formed as an inclined surface, and the inclined surface is inclined inward gradually from the lower end to the upper end. The side surface of the sealing member 4 is also set to be gradually contracted toward the second end, that is, the side surface of the sealing member 4 close to the valve cover 1 may be set to be an inclined surface, and the inclined surface is gradually contracted toward the second end, of course, the side surface may also be set to be an arc surface. And the area and shape of both contact surfaces of the sleeve 512 and the seal 4 are the same, i.e., the area and shape of the surface of the sleeve 512 in contact with the seal 4 are the same as those of the surface of the seal 4 in contact with the sleeve 512.

The guide member 5 also functions as a weight. When the piston of the oil well pump moves upwards, the guide assembly 5 is prevented from inclining due to the larger gravity of the guide assembly 5; when the piston of the oil well pump moves downwards, the guide assembly 5 is easy to press down due to the large gravity of the guide assembly 5.

Further, this example embodiment still provides an oil-well pump, and this disclosed embodiment still provides an oil-well pump, as shown in fig. 4, and the oil-well pump includes pump barrel 200, piston and valve structure 100, wherein:

the pump barrel 200 may include an oil inlet end and an oil outlet end, with the piston slidably disposed within the pump barrel 200. The valve structure 100 can be arranged in the pump barrel 200, and when the valve structure is used as a fixed valve, the second open end of the valve cover 1 of the valve structure 100 can be fixedly butted with the oil inlet end of the pump barrel 200 along the axial direction; when it is a floating valve, it can be disposed between the oil inlet end and the oil outlet end of the pump barrel 200, and the structural details and beneficial effects of the valve structure 100 can be found in any of the above embodiments, which are not described herein again.

The oil well pump can be provided with a plurality of valve structures which can be sequentially arranged from bottom to top along the axial direction of the pump barrel 200. For example, it may be three, a first valve, a second valve and a third valve. At least one of the first valve and the second valve is the valve structure 100 of any of the embodiments described above. If the first valve is the valve structure 100, the second end of the valve cover 1 of the first valve is fixedly butted with the oil inlet end of the pump cylinder 200 along the axial direction, and the second valve is arranged in the pump cylinder 200; if the second valve is the valve structure 100, the second end of the valve cover 1 of the second valve is fixedly butted with the piston along the axial direction. The third valve is arranged at the oil outlet end of the pump barrel 200 and is fixedly butted with one end of the piston far away from the oil inlet end.

The first valve, the second valve, and the third valve may be the valve structure 100 of the above embodiment, but the first valve, the second valve, and the third valve may be the valve structures 100 of different embodiments, and are not limited to being completely identical.

The following describes the operation of the oil pump according to the embodiment of the present disclosure:

the pump barrel 200 is vertically arranged on the ground, and the first valve, the second valve and the third valve are arranged from bottom to top. When oil is pumped, the piston moves upwards, the pressure in the pump barrel 200 is reduced, negative pressure is formed, and the first valve plugging piece 3 is separated from the valve seat 2, so that the oil inlet end is opened, and a passage is provided for the circulation of oil; meanwhile, the plugging pieces 3 of the second valve and the third valve are respectively contacted with the corresponding valve seats 2, so that the second valve and the third valve are closed; at this time, oil may enter the pump barrel 200 from the oil inlet end, and oil between the second valve and the third valve is lifted. When the piston moves downwards, the pressure in the pump cylinder 200 is increased, the plugging piece 3 of the first valve moves downwards under the action of oil pressure, and the side surface 32 of the plugging piece 3 is abutted against the top end part of the valve seat 2, so that the sealing between the plugging piece 3 and the valve seat 2 is realized, and the backflow of petroleum along a circulation channel is avoided. Meanwhile, the plugging pieces 3 of the second valve and the third valve are both jacked open and separated from the corresponding valve seats 2, so that the second valve and the third valve are opened; at this time, oil can be output from the oil outlet end. In this process, the seal ring 6 can seal the assembly gap between the inner circumferential surface of the valve cover 1 and the outer circumferential surface of the valve seat 2, thereby preventing oil from flowing back and leaking from the assembly gap between the valve seat 2 and the valve cover 1 and improving the oil extraction.

The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments, and the features discussed in connection with the embodiments are interchangeable, if possible. In the description above, numerous specific details are provided to give a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

Although relative terms, such as "upper" and "lower," may be used in this specification to describe one element of an icon relative to another, these terms are used in this specification for convenience only, e.g., in accordance with the orientation of the examples described in the figures. It will be appreciated that if the device of the icon were turned upside down, the element described as "upper" would become the element "lower". Other relative terms, such as "high", "low", "top", "bottom", and the like, are also intended to have similar meanings. When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via another structure.

In this specification, the terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.; the terms "first," "second," and "third," etc. are used merely as labels, and are not limiting on the number of their objects.

It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the description. The present invention is capable of other embodiments and of being practiced and carried out in a variety of ways. The foregoing variations and modifications fall within the scope of the present invention. It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments set forth herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.

Claims

1. A valve structure, comprising:

2. The valve structure of claim 1, wherein the guide assembly further comprises:

3. The valve structure of claim 2, wherein the guide post comprises:

4. A valve arrangement according to claim 3, wherein the side of the end of the sleeve abutting the seal tapers towards the second end.

5. A valve structure according to claim 4, wherein the side of the sealing member is tapered towards the second end, and the two contact surfaces of the sleeve and the sealing member that contact each other are of the same area and shape.

6. A valve structure according to claim 1, characterized in that the surface of the cuff in abutment with the tip portion has at least one annular ridge surrounding the closure member.

7. A valve structure according to claim 6, wherein the surface of the annular ridge that abuts the top end is a curved surface.

8. A valve structure according to claim 1, further comprising:

and the sealing ring is arranged between the valve seat and the valve cover.

9. A valve structure according to claim 1, characterized in that the blocking piece is a segment structure, the bottom surface is a bottom surface of the segment structure, and the side surfaces are spherical crowns of the segment structure.

10. An oil-well pump, its characterized in that includes:

the plunger is slidably arranged in the pump cylinder;

the valve structure of any one of claims 1 to 9, wherein the valve structure is disposed in the pump barrel, and the second end of the valve cover of the valve structure is fixedly butted against the oil inlet end of the pump barrel along the axial direction.