CN213052745U

CN213052745U - Manufacturing die for radial centralizing sliding bearing moving ring

Info

Publication number: CN213052745U
Application number: CN202021207872.2U
Authority: CN
Inventors: 赵红梅
Original assignee: Beijing Chunlun Petroleum Technology Development Co ltd
Current assignee: Beijing Chunlun Petroleum Technology Development Co ltd
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2021-04-27
Anticipated expiration: 2030-06-28

Abstract

The utility model provides a radially right manufacturing mould of slide bearing rotating ring, this mould includes: the wear-resistant part comprises a base body, a cover die, a wear-resistant part and a cover plate, wherein the base body is a hollow rotary body and is made of manganese-containing alloy steel; the cover die is hollow solid of revolution, the coaxial cover of cover die is established the periphery of base member, the inner wall of cover die with form annular space between the outer wall of base member, wear-resisting piece sets up on the inner wall of cover die, wear-resisting material includes: cemented carbide or/and polycrystalline diamond; the upper end of the cover die is higher than the preset height of the base body, the cover plate is arranged at the upper end of the cover die, a preset containing space is formed among the cover die, the base body and the cover plate, and the containing space is used for placing a positioning layer, bonding alloy and fluxing agent. Utilize the utility model discloses the rotating ring of making can improve the radial life who rights slide bearing, reduces the machining degree of difficulty and manufacturing cost simultaneously.

Description

Manufacturing die for radial centralizing sliding bearing moving ring

Technical Field

The utility model relates to a drilling is with metalworking of downhole tool makes technical field, especially relates to a manufacturing mould of slide bearing rotating ring is radially right to rotary steering system.

Background

The radial centralizing sliding bearing is a vulnerable part of a drilling downhole tool, and when the downhole tool is repaired, the replacement of the radial centralizing sliding bearing is one of main working contents. At present, radial centralizing sliding bearings of downhole tools are basically radial centralizing hard alloy sliding bearings (TC bearings for short), wear-resistant materials of working surfaces of a static ring and a moving ring are strip-shaped hard alloy blocks, although the hardness of hard alloys is high (HRA 89-92), due to the fact that drilling fluid contains a large number of solid-phase particles (such as iron ore powder, quartz sand and the like), the micro-particles can cause serious abrasive wear to the wear-resistant materials of the friction working surfaces of the static ring and the moving ring of the bearing when passing through a centralizing bearing working gap, and the service life of the TC bearings is only 150-200 h (the higher the solid-phase content of the drilling fluid is, the shorter the service life of the bearing).

In the aspect of manufacturing process, the TC bearing is made into domestic development after being introduced into China from the end of the last 90 th century. Due to the reasons of technical confidentiality and economic benefit, key technologies of various domestic development units related to the mold, the manufacturing method and the like of the TC bearing cannot be mutually exchanged, and related literature reports do not exist, so that the mold and the manufacturing process of the TC bearing are various, the rejection rate is high, and the method is mainly characterized in that: the hardness of the base material of the static ring and the dynamic ring finished product cannot reach HRC 32-36 (generally only HRC 25-30) required by the parts of the downhole tool; impurities (shown as black holes with different sizes) exist in the adhesives of the tungsten carbide cast by the static ring and the moving ring and the copper-based alloy, the bonding strength between the hard alloy wear-resistant material and the tungsten carbide cast is low (less than or equal to 60MPa), and the service life of the sliding bearing is short; secondly, when the cast tungsten carbide is too much, turning is difficult (turning cannot be performed), the manufacturing cost is high, the cost performance is low, and the requirement of an actual drilling downhole tool cannot be met.

Therefore, there is a need for a new mold for manufacturing a radially-centered plain bearing rotating ring that overcomes at least one of the deficiencies of the prior art.

It should be noted that the above background description is only for the sake of clarity and complete description of the technical solutions of the present invention, and is set forth for facilitating understanding of those skilled in the art. These solutions are not considered to be known to the person skilled in the art merely because they have been set forth in the background section of the present invention.

SUMMERY OF THE UTILITY MODEL

In order to overcome at least one defect among the prior art, the utility model provides a radially right manufacturing mould of slide bearing rotating ring can improve finished product base member material hardness and radially right slide bearing's working life, reduces the machining degree of difficulty and manufacturing cost simultaneously, and the facilitate promotion is used.

In order to achieve the above object, the present invention provides the following technical solutions.

A mold for manufacturing a radial centering sliding bearing rotating ring, comprising: the wear-resistant part comprises a base body, a cover die, a wear-resistant part and a cover plate, wherein the base body is a hollow rotary body and is made of manganese-containing alloy steel; the cover die is hollow solid of revolution, the coaxial cover of cover die is established the periphery of base member, the inner wall of cover die with form annular space between the outer wall of base member, wear-resisting piece sets up on the inner wall of cover die, wear-resisting material includes: cemented carbide or/and polycrystalline diamond; the upper end of the cover die is higher than the preset height of the base body, the cover plate is arranged at the upper end of the cover die, a preset containing space is formed among the cover die, the base body and the cover plate, and the containing space is used for placing a positioning layer, bonding alloy and fluxing agent.

In a preferred embodiment, at least a first inner cylindrical surface, a second inner cylindrical surface and a third inner cylindrical surface are arranged on the inner wall of the sleeve die from bottom to top, the diameter of the first inner cylindrical surface is larger than that of the second inner cylindrical surface, and a first lower limiting part is formed between the first inner cylindrical surface and the second inner cylindrical surface; the diameter of the third inner cylindrical surface is larger than that of the second inner cylindrical surface, and an annular conical surface with a low middle part and a high periphery is formed between the third inner cylindrical surface and the second inner cylindrical surface.

In a preferred embodiment, the outer wall of the base body comprises at least a first outer cylindrical surface abutting against the first inner cylindrical surface and a second outer cylindrical surface cooperating with the second inner cylindrical surface; an annular gap is formed between the second inner cylindrical surface and the second outer cylindrical surface; the diameter of the first outer cylindrical surface is larger than that of the second outer cylindrical surface, a second lower limiting part is formed between the first outer cylindrical surface and the second outer cylindrical surface, and the first lower limiting part and the second lower limiting part are matched to form a limiting mechanism.

In a preferred embodiment, the diameter of the third inner cylindrical surface is equal to the diameter of the second inner cylindrical surface.

In a preferred embodiment, the upper end of the base body is a sealed end, and the lower end of the base body is an open end; the upper end of the base body is provided with a cylinder cover, and the cylinder cover and the upper end of the base body are welded, sealed and fixed; and the periphery of the lower end of the base body is welded, sealed and fixed with the second end of the cover die.

In a preferred embodiment, a third outer cylindrical surface is further arranged on the outer wall of the base body, the diameter of the third outer cylindrical surface is smaller than that of the second outer cylindrical surface, and a compensating ring is coaxially arranged outside the third outer cylindrical surface and the second outer cylindrical surface.

In a preferred embodiment, a fourth outer cylindrical surface is arranged on the outer wall of the compensating ring, and a fourth inner cylindrical surface and a fifth inner cylindrical surface are arranged on the inner wall of the compensating ring; the fourth inner cylindrical surface is in clearance fit with the third outer cylindrical surface, and the fifth inner cylindrical surface is in clearance fit with the second outer cylindrical surface; a second upper limit part is formed between the fourth outer cylindrical surface and the second outer cylindrical surface; an annular gap is formed between the fourth outer cylindrical surface and the annular conical surface and between the fourth outer cylindrical surface and the third inner cylindrical surface and is used for accommodating the positioning layer; the compensation ring is welded and fixed with the upper end of the base body.

In a preferred embodiment, the second inner cylindrical surface is provided with a groove.

In a preferred embodiment, the lower end of the sleeve die is fixedly transition-fit-welded with the periphery of the lower end of the base body to form a sealing end.

In a preferred embodiment, the cover plate is provided with air holes.

In a preferred embodiment, the second inner cylindrical surface is further provided with a positioning portion for positioning the wear-resistant member.

The utility model discloses embodiment provides a brand-new manufacturing mould of radially righting slide bearing rotating ring, has comprehensively considered product property ability, actual production's feasibility and cost of manufacture etc. factor, during the implementation, based on the rotating ring manufacturing mould that acquires, utilizes steps such as benchmark location, washing, bonding, equipment filler, sintering and machining, has obtained the radially righting slide bearing rotating ring of an ideal. On the whole, can improve finished product base member material hardness and radially right the working life of slide bearing, reduce the machining degree of difficulty and manufacturing cost simultaneously, can satisfy the user demand of modern well drilling downhole tool better, facilitate promotion and application.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and the accompanying drawings, which specify the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the present invention are not so limited in scope.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments, in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein, is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for helping the understanding of the present invention, and do not specifically limit the shapes, the proportional sizes, and the like of the respective members of the present invention. The skilled person in the art can, under the teaching of the present invention, choose various possible shapes and proportional dimensions to implement the invention according to the specific situation. In the drawings:

FIG. 1 is a schematic cross-sectional view of a radially-centered plain bearing rotating ring constructed in accordance with the teachings of the present application;

FIG. 2A is a schematic longitudinal cross-sectional view of a mold assembly for radially centering a sliding bearing rotating ring according to a first embodiment of the present disclosure;

FIG. 2B is a schematic longitudinal sectional view of the movable ring base in FIG. 2A;

FIG. 2C is a schematic longitudinal sectional view of the shell mold shown in FIG. 2A;

FIG. 2D is a schematic view of the second inner cylindrical surface of the die of FIG. 2C after being expanded in the circumferential direction;

FIG. 2E is a schematic cross-sectional view of the second inner cylindrical surface of the sleeve mold shown in FIG. 2C with the wear-resistant member adhered thereto;

FIG. 2F is the second inner cylindrical surface of the sleeve die shown in FIG. 2E after the wear-resistant member is adhered and expanded along the circumferential direction;

FIG. 2G is a schematic longitudinal cross-sectional view of the compensating ring of FIG. 2A;

FIG. 3 is a schematic cross-sectional view of another radial-righting plain bearing rotating ring constructed in accordance with the teachings of the present application;

FIG. 4A is a schematic longitudinal cross-sectional view of a mold assembly for radially centering a sliding bearing rotating ring according to a second embodiment of the present disclosure;

FIG. 4B is a schematic longitudinal sectional view of the substrate of FIG. 4A;

FIG. 5A is a schematic longitudinal cross-sectional view of a mold assembly for radially centering a sliding bearing rotating ring according to a third embodiment of the present application;

FIG. 5B is a schematic longitudinal sectional view of the substrate of FIG. 5A;

FIG. 6 is a schematic cross-sectional view of yet another radial-righting plain bearing rotating ring constructed in accordance with the teachings of the present application;

FIG. 7A is a schematic longitudinal cross-sectional view of a mold assembly for radially centering a sliding bearing rotating ring according to a fourth embodiment of the present application;

FIG. 7B is a schematic longitudinal sectional view of the substrate of FIG. 7A;

FIG. 7C is a schematic longitudinal sectional view of the shell mold of FIG. 7A;

fig. 8 is a schematic flow chart of a manufacturing mold for radially centering a sliding bearing rotating ring according to an embodiment of the present disclosure.

Description of reference numerals:

1. a substrate; 11. a first outer cylindrical surface; 12. a second outer cylindrical surface; 13. a third outer cylindrical surface; 14. a groove; 15. a second lower limit portion; 16. a cylinder cover; 18. a second upper limit portion; 19. a fifth outer cylindrical surface; 20. a sixth outer cylindrical surface;

2. casting tungsten carbide;

3. a wear part;

4. sleeving a mold; 41. a first inner cylindrical surface; 42. a second inner cylindrical surface; 43. an annular conical surface; 44. a positioning part; 45. a first lower limit part; 46. a third inner cylindrical surface; 47. designing a height position;

5. a binder alloy;

6. a positioning layer;

7. a compensation ring; 71. a fourth inner cylindrical surface; 72. a fifth inner cylindrical surface; 73. a lower end face; 74. a fourth outer cylindrical surface; 75. a first upper limiting portion;

8. fluxing agent;

9. a cover plate; 91. and (4) air holes.

Detailed Description

In order to make the technical solutions in the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall fall within the protection scope of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

To the above-mentioned problem that exists among the prior art, utility model people propose a radial righting slide bearing that is provided with carbide and/or polycrystalline diamond wearing parts according to nearly thirty years's relevant scientific research experience and replace current TC bearing. The radial-righting sliding bearing comprises a static ring and a dynamic ring which are matched. In the present application, the manufacturing technique of a radial-righting plain bearing rotating ring is mainly described.

In the embodiment of the application, the radial-centering sliding bearing moving ring to be manufactured can be adaptively designed according to the requirements of specific assembly environments.

Specifically, as shown in fig. 1 or fig. 3, a schematic cross-sectional structure diagram of a radial-centering sliding bearing rotating ring is shown, where the rotating ring includes: the wear-resistant material comprises a hollow base body 1, wherein cast tungsten carbide 2 and a compensating ring 7 are arranged on the outer surface of the base body 1, and a plurality of wear-resistant pieces 3 are arranged in the cast tungsten carbide 2. The moving ring structure provided in fig. 1 or fig. 3 has a height of the matrix 1 greater than that of the cast tungsten carbide 2, i.e., both ends of the matrix 1 are coated with the cast tungsten carbide 2. Wherein the moving ring structure provided in fig. 1 is suitable for most radially-centered scenes. The rotating ring structure provided in fig. 3 is suitable for some type of push-against rotary steerable system or downhole motor.

Fig. 6 is a schematic cross-sectional view of a radial-centering sliding bearing moving ring. The height of the tungsten carbide 2 cast in the movable ring is the same as that of the matrix 1, and the movable ring is suitable for partial drilling downhole tools, such as a turbine drilling tool turbine section radial centering sliding bearing, a screw drilling tool transmission shaft radial centering sliding bearing and the like.

Preliminary practice proves that the service life of the novel radial centralizing sliding bearing moving ring can reach more than 300-600 h, the hardness of the matrix 1 is HRC 32-36, the bonding strength among the wear-resistant part 3, the cast tungsten carbide 2, the compensating ring 7 and the matrix 1 is not less than 60MPa, and the requirements of drilling downhole tools can be met.

In order to manufacture the radial centralizing sliding bearing meeting the requirements of the actual drilling downhole tool, the application provides a corresponding manufacturing mold of the radial centralizing sliding bearing moving ring.

As shown in fig. 2A or fig. 4A or fig. 5A or fig. 7A, the mold for manufacturing a radial-centering sliding bearing rotating ring provided in the embodiment of the present application mainly includes: the base body 1 used as the base of the rotating ring and the cover die 4 used as the main body of the die.

As shown in fig. 2A-2G, a mold 001 for radially centering a sliding bearing rotating ring (shown in fig. 1) provided in an embodiment of the present application is provided. As shown in fig. 2B, the substrate 1 is a hollow cylinder. As shown in fig. 2C, the cover die 4 has a ring shape with a central hole. The inner wall of the cover die 4 and the outer wall of the base body 1 form an annular gap for arranging the wear-resistant part 3. The material of the substrate 1 can be alloy steel containing manganese element. Specifically, it may be 40CrMnMo or 40 CrMnMoA. The applicant found that: the 40CrMnMo and 40CrMnMoA have good mechanical properties after air cooling, particularly the hardness which can reach HRC 32-36, and the hardness is improved by avoiding using the traditional heat treatment process of high-temperature quenching and low-temperature tempering, so that the manufacturing process is effectively simplified, and the manufacturing cost is greatly reduced.

The wear-resistant part 3 is made of the following materials: cemented carbide and/or polycrystalline diamond. The two materials are wear-resistant materials with extremely high hardness, in particular polycrystalline diamond materials which can be used as blades of metal cutting pieces or drill bits and teeth and the like. After the wear-resistant part 3 is made of the materials, the service life of the wear-resistant part 3 can be greatly prolonged. Since the service life of the radial centralizing slide bearing mainly depends on the degree of wear of the wear-resistant part 3, after the service life of the wear-resistant part 3 is prolonged, the service life of the bearing is ensured to be longer. However, it is a technical difficulty in the art how to reliably fix the above-mentioned wear-resistant material with extremely high hardness, particularly polycrystalline diamond material, on the substrate 1. That is, at present, no process method with high efficiency, reliability, low cost and market popularization prospect exists.

In the axial direction of the die 4, the die 4 has a first end and a second end opposite to each other, and the first end has a height higher than that of the base 1. A cover plate 9 is arranged at the first end of the cover die 4, and a containing space for placing the positioning layer 6, the bonding alloy 5 and the fluxing agent 8 is formed among the cover plate 9, the cover die 4 and the base body 1. The bonding alloy 5 may be one or a mixture of any of copper-based alloy, nickel-based alloy, cobalt-based alloy and zinc-based alloy.

The material of the positioning layer 6 comprises any one or combination of the following materials: tungsten powder and iron powder. On the whole, the material of this locating layer 6 can choose for use melting point and density all to be higher than tungsten trioxide, and the material of easy machine tooling.

During subsequent fabrication, the assembly height of the cast tungsten carbide 2 is difficult to control accurately, i.e., the amount of cast tungsten carbide 2 used prior to sintering is difficult to determine accurately. Specifically, if the cast tungsten carbide 2 is added in an amount up to the design height, the applicant found that: the upper end surface of the cast tungsten carbide 2 is often deposited with some impurities (most of the impurities are oxides, such as yellow tungsten trioxide). The impurities form a yellow structure with holes at the upper end of the cast tungsten carbide 2, which not only affects the performance of the product, but also affects the appearance of the product and is difficult to meet the requirements of actual products.

To address the situation where impurities are present at the top, one theoretically possible way is: the dosage of the cast tungsten carbide 2 is increased in the early stage, namely the height of the added cast tungsten carbide 2 is higher than the design height, and then impurities and redundant cast tungsten carbide are removed. However, when the cast tungsten carbide 2 is added and then machined, the hardness and wear ratio of the sintered cast tungsten carbide alloy are particularly high, the turning removal is very difficult, and the cost is high.

In order to reasonably control the amount of the cast tungsten carbide 2 to achieve an ideal height (i.e. a designed height) without excess, and simultaneously achieve impurity isolation, an ingenious mode is adopted in the embodiment of the application. The method comprises the following steps: during the filling of the material, cast tungsten carbide 2 is first added to a designed height, and then a positioning layer 6 of a predetermined height is added above the cast tungsten carbide 2.

In one embodiment, the positioning layer 6 may be formed by iron powder. In the case of high-temperature sintering, the cast tungsten carbide 2, which contains tungsten as a main component (about 95.58%), is easily oxidized to form yellow tungsten trioxide and forms impurities in excess tungsten that is not carbonized under high-temperature aerobic conditions. The specific gravity of the tungsten trioxide is 7.16g/cm³The specific gravity of the iron powder is 7.8g/cm³And impurities floating from the gaps of the cast tungsten carbide 2 powder are not accumulated on the upper end surface of the cast tungsten carbide 2 but accumulated above the iron powder because the density of the impurities is less than that of the iron, so that the subsequent machining is facilitated. And removing all or part of the iron powder in the annular gap during machining. In order to prevent the liquid loss of the molten bonding alloy 5 during the subsequent sintering, the periphery of the lower end of the substrate 1 and the second end of the cover die 4 can be welded, sealed and fixed in a welding mode after the powdered cast tungsten carbide 2 is compacted or the powdered cast tungsten carbide is put into the iron powder.

The iron powder can ensure that the height of the cast tungsten carbide 2 reaches the design height, and impurities are isolated, the iron powder is low in price and easy to purchase, and after sintering, the iron powder gaps are filled with the bonding alloy 5, so that the iron powder can be well bonded with the matrix 1, has certain tensile strength and shearing strength, and is easy to machine.

In another embodiment, the positioning layer 6 may also be selected from tungsten powder, which not only has a high melting point, but also does not introduce new impurities.

In particular, the height h of the positioning layer 6 may be at least 3 mm. The applicant proves that: when the thickness h of the positioning layer is equal to or greater than 3 mm, it can satisfy the above-described performance requirements. The alignment layer 6 may be partially or completely removed in subsequent machining. The thickness can reliably ensure that impurities floating from gaps of the cast tungsten carbide 2 (powder, namely powder) during high-temperature sintering are not accumulated on the upper end surface of the cast tungsten carbide 2 but accumulated above the positioning layer 6, so that the impurities can be conveniently removed by a machining method in the subsequent process.

In this embodiment, a cover plate 9 is provided at the first end of the die 4 to prevent excessive oxidation of the binder alloy 5 during high temperature sintering. Specifically, the cover plate 9 may be a circular steel plate having a certain thickness. For example, the cover plate 9 can be made of a 15# or 20# steel plate with a thickness of 4-6 mm, which is convenient for material selection and easy for machining.

The cover plate 9 may be in non-sealing fit with the first end of the cover die 4, so as to leave a certain gap for exhausting the internal air during high-temperature sintering. In addition, in order to ensure that the internal air can be reliably discharged during high-temperature sintering, and avoid safety accidents caused by gas expansion due to high-temperature heating, the cover plate 9 can be further provided with air holes 91.

In this embodiment, the second inner cylindrical surface 42 of the shell mold 4 is used for positioning the wear part 3. The inner wall of the cover die 4 is provided with an annular conical surface 43, and when the annular conical surface 43 is in a conical surface shape with a low middle part and a high periphery, on one hand, the consumption of the bonding alloy 5 can be saved, and on the other hand, the melted bonding alloy 5 can be uniformly guided into the annular gap along the circumferential direction. Specifically, the taper angle of the annular tapered surface 43 may be between 90 ° and 150 °.

In this embodiment, at least a first inner cylindrical surface 41, a second inner cylindrical surface 42, and a third inner cylindrical surface 46 are disposed on the inner wall of the sleeve mold 4 from the second end to the first end, the diameter of the first inner cylindrical surface 41 is greater than the diameter of the second inner cylindrical surface 42, and a first lower limit portion 45 is formed between the first inner cylindrical surface 41 and the second inner cylindrical surface 42. In particular, the first lower limiting portion 45 may be in the form of a limiting shoulder.

In this embodiment, the outer wall of the base body 1 includes at least a first outer cylindrical surface 11 abutting against the first inner cylindrical surface 41 and a second outer cylindrical surface 12 cooperating with the second inner cylindrical surface 42. The annular gap is formed between the second inner cylindrical surface 42 and the second outer cylindrical surface 12. The diameter of the first outer cylindrical surface 11 is greater than the diameter of the second outer cylindrical surface 12. A second lower limit portion 15 is formed between the first outer cylindrical surface 11 and the second outer cylindrical surface 12. The first lower stopper 45 and the second lower stopper 15 cooperate to form a stopper mechanism. The second lower limit portion 15 may also be in the form of a limit shoulder. When the first lower limit portion 45 and the second lower limit portion 15 are engaged, the sleeve 4 and the base 1 are positioned in a radial direction and can be axially limited, and cannot move any further in the opposite direction.

In the present embodiment, the base body 1 is a hollow cylinder body having opposite upper and lower ends; the upper end of the base body 1 is a sealing end, and the lower end of the base body is an opening end; a cylinder cover 16 is arranged at the upper end of the base body 1, and the cylinder cover 16 is welded, sealed and fixed with the upper end of the base body 1; the periphery of the lower end of the base body 1 is welded, sealed and fixed with the second end of the cover die 4.

In the present embodiment, a third outer cylindrical surface 13 is further disposed on the outer wall of the base body 1, and the diameter of the third outer cylindrical surface 13 is smaller than the diameter of the second outer cylindrical surface 12. And a compensating ring 7 is coaxially arranged on the outer side of the third outer cylindrical surface 13 and the outer side of the second outer cylindrical surface 12. The separate installation of the compensation ring 7 and the base body 1 ensures that the parts of the mold are assembled without interference before sintering, and efficient filling is possible. The compensating ring 7 can subsequently be welded firmly to the base body 1 in one piece during sintering.

As shown in fig. 2G, the compensating ring 7 may be a hollow variable inner diameter solid of revolution, and a fourth outer cylindrical surface 74 is disposed on the outer wall thereof, and a fourth inner cylindrical surface 71 and a fifth inner cylindrical surface 72 are disposed on the inner wall thereof. A first upper limit portion 75 is formed at the boundary position between the fourth inner cylindrical surface 71 and the fifth inner cylindrical surface 72. Specifically, the inner diameter of the fourth inner cylindrical surface 71 may be smaller than the inner diameter of the fifth inner cylindrical surface 72, so as to form the first upper stopper 75, and the first upper stopper 75 may be formed in the form of a stopper step. The fourth inner cylindrical surface 71 is in clearance fit with the third outer cylindrical surface 13, and the fifth inner cylindrical surface 72 is in clearance fit with the second outer cylindrical surface 12; the annular gap portion formed between the fourth outer cylindrical surface 74 and the annular tapered surface 43 and the third inner cylindrical surface 46 is used for accommodating the positioning layer 6; the compensation ring 7 is welded and fixed with the upper end of the base body 1. The material of the compensation ring 7 may be the same as that of the substrate 1. Specifically, the material of the compensation ring 7 may be 40CrMnMo or 40 CrMnMoA.

In the present embodiment, the cover plate 9 is provided with air holes 91.

As shown in fig. 2D, in the present embodiment, a positioning portion 44 for positioning the wear-resistant member 3 is further provided on the second inner cylindrical surface 42. The positioning portions 44 may be reference lines provided on the second inner cylindrical surface 42 by coating, pasting, or the like in a predetermined arrangement. The maximum distance between the wear-resistant pieces 3 is usually 2-5 mm, and must be smaller than the width of the wear-resistant pieces 3, and the coverage area of the wear-resistant pieces 3 on the friction surface is usually 70% -80%. Specifically, as shown in fig. 2E and 2F, the wear-resistant member 3 may be rectangular as a whole, and the shape of the wear-resistant member 3 is not limited to the above shape, and may be other shapes.

Further, a second upper stopper 18 is formed at a boundary position between the second outer cylindrical surface 12 and the third outer cylindrical surface 13. The second upper limit portion 18 may be in the form of a limit step. When the second upper stopper 18 is engaged with the first upper stopper 75, an upper stopper mechanism is formed to position and fix the cast tungsten carbide 2 and the binder alloy 5.

Furthermore, the second outer cylindrical surface 12 may be provided with a groove 14 to increase the bonding surface area of the bonding alloy 5, so as to greatly improve the bonding strength between the sintered cast tungsten carbide 2, the cemented carbide or/and the polycrystalline diamond wear-resistant part 3 and the substrate 1. In particular, the form of the recess 14 may comprise a helical or annular groove. Of course, the form of the groove 14 may be other forms, and the present application is not limited thereto.

In the present embodiment, the second end of the cover die 4 is in transition fit with the periphery of the lower end of the base body 1 to form a sealing end. Wherein the sealing fixed fit may be secured by direct welding.

As shown in fig. 4A to 4B and fig. 2C to 2G, a mold 002 for radially centering a sliding bearing rotating ring (shown in fig. 3) provided in another embodiment of the present application is provided.

As shown in fig. 5A, 5B, and 2C to 2G, a mold 003 for radially centering a plain bearing rotating ring (shown in fig. 3) provided in yet another embodiment of the present application is provided.

As shown in fig. 7A, 7B and 7C, a mold 004 for radially centering a sliding bearing moving ring is proposed for the moving ring structure of fig. 6. Specifically, as shown in fig. 7B and 7C, the mold 004 is mainly different from the above embodiment in structure in that: the second inner cylindrical surface 42 is the same cylindrical surface as the third inner cylindrical surface 46. The second inner cylindrical surface 42 and the third inner cylindrical surface 46 are the same cylindrical surface, and the boundary position thereof is the designed height position 47. The design height position 47 is the highest position after filling the cast tungsten carbide 2 powder and compacting. Other structures of the mold 004 can refer to the specific description of the above embodiments, and the detailed description of the present application is omitted.

For several embodiments of the above-mentioned mold for the radially-centering sliding bearing moving ring, the overall steps of the manufacturing method for the radially-centering sliding bearing moving ring are substantially the same, and there are only some differences in details. The following description will be made of a mold 001 for radially centering a plain bearing rotating ring (shown in fig. 1) according to a first embodiment of the present invention.

As shown in fig. 8, the method for manufacturing a radial-centering sliding bearing rotating ring (shown in fig. 1) provided in the first embodiment of the present application may include the following steps:

step S10: obtaining a manufacturing mold, wherein the manufacturing mold comprises a base body 1, a sleeve mold 4 coaxially placed outside the base body 1, and a cover plate 9 arranged at the upper end of the sleeve mold 4, an annular space is formed between the sleeve mold 4 and the base body 1, and an accommodating space is formed among the sleeve mold 4, the base body 1 and the cover plate 9;

step S12: setting a positioning reference, including setting a reference line on the second inner cylindrical surface 42 of the cover die 4 according to a preset arrangement mode, for positioning the wear-resistant part 3; the wear-resistant part 3 is made of the following materials: cemented carbide or/and polycrystalline diamond;

step S14: cleaning the part to be bonded, including cleaning the inner cylindrical surface of the cover die 4, the outer cylindrical surface of the base body 1 and the surface of the wear-resistant part 3;

step S16: pasting the wear-resistant pieces 3, including pasting the wear-resistant pieces 3 on the second inner cylindrical surface 42 of the sleeve die 4 based on the set reference line according to the preset arrangement mode;

step S18: assembling the filler, firstly, coaxially sleeving the sleeve mold 4 adhered with the wear-resistant part 3 on the outer side of the base body 1, wherein at the moment, the first outer cylindrical surface 11 of the base body 1 abuts against the first inner cylindrical surface 41 of the sleeve mold 4, and the second lower limit part 15 of the base body 1 abuts against the first lower limit part 45 of the sleeve mold 4; next, the compensation ring 7 is coaxially sleeved outside the base body 1 (which may be fixed by welding to prevent displacement during subsequent vibration or sintering), and at this time, the third outer cylindrical surface 13 of the base body 1 abuts against the fourth inner cylindrical surface 71 of the compensation ring 7, and the second upper limit portion 18 of the base body 1 abuts against the first upper limit portion 75 of the compensation ring 7, so as to form an upper limit mechanism in a matching manner. In addition, after the compensation ring 7 is assembled on the base body 1, the inner wall of the compensation ring 7 is matched with the second upper limiting part 18 of the base body 1, and the lower end surface 73 of the compensation ring 7 is used as the highest position of the cast tungsten carbide powder, so that the cast tungsten carbide 2 and the bonding alloy 5 can be positioned during sintering.

Secondly, pouring the powdery casting tungsten carbide 2 into the residual gap of the annular space between the cover die 4 and the substrate 1, placing positioning powder above the casting tungsten carbide 2 after compaction to form a positioning layer 6, then placing a certain amount of bonding alloy 5 in proportion, and uniformly spraying a certain amount of fluxing agent 8 on the bonding alloy 5 in proportion; finally, cover the cover plate 9;

step S20: sintering, namely placing the assembled and filled mold into a high-temperature sintering furnace to be sintered by adopting a pressureless dipping process, and obtaining a moving ring blank after sintering;

step S22: and machining, namely taking the moving ring blank out of the sintering furnace, performing air cooling, and machining the moving ring blank after the temperature is reduced to room temperature, so that the size of the moving ring meets the design technical requirement.

Specifically, before the method for manufacturing the radial-centering sliding bearing moving ring provided by the application is carried out, some preparation work needs to be firstly carried out. These preparation works include:

obtaining a required specification and quantity of a die set 4 (for example, the material can be low carbon steel), a base body 1 (for example, the material can be 40CrMnMo or 40CrMnMoA), a cylinder cover 16 (for example, the material can be 15# or 20# steel, the cylinder cover 16 and the base body 1 can be sealed and fixed by welding), a cover plate 9 (for example, the material can be 15# or 20# steel), a bonding alloy 5 (for example, the material can be copper-based alloy), a fluxing agent 8 (for example, the material can be anhydrous sodium tetraborate Na₂B₄O₇) Wear-resistant part 3 (cemented carbide), adhesive (for example, the material may be 502 glue), etc. On the inner wall of the cover die 4, specifically, on the second inner cylindrical surface 42 of the cover die 4, a sticking reference line is drawn according to the arrangement scheme of the wear-resistant members 3.

Then formally entering a preparation stage. During the preparation process, a cleaning step is first performed, specifically, the cover die 4, the base body 1 and the wear-resistant part 3 are cleaned to ensure the cleanliness of the bonding positions. Specifically, the positions to be bonded include: the second inner cylindrical surface 42 of the cover die 4, the second outer cylindrical surface 12 of the base body 1 and the surface of the wear-resistant part 3, so that the positions are free from dirt and impurities which influence the bonding performance.

After the cleaning is finished, executing a pasting step: according to the arrangement scheme of the wear-resistant pieces 3, referring to the marked pasting reference line on the second inner cylindrical surface 42 of the sleeve die 4, the cleaned hard alloy wear-resistant pieces 3 are pasted on the second inner cylindrical surface 42 of the sleeve die 4 one by using an adhesive, the wear-resistant pieces 3 are lightly compacted and flattened by fingers, and whether the wear-resistant pieces 3 are pasted firmly or not is checked.

After the above-described attaching step is completed, the mold may be assembled as shown in fig. 2A. Specifically, the cover die 4 is first placed coaxially outside the base body 1. On the basis, the corresponding filling step is carried out.

When the filling step is executed, pouring a proper amount of powdered cast tungsten carbide 2 into a residual gap of an annular space between the cover die 4 and the substrate 1, compacting on a vibration machine, and calculating the actual using amount of the cast tungsten carbide 2; and coaxially sleeving the compensation ring 7 on the outer side of the matrix 1 and welding and fixing the compensation ring, and placing a small amount of iron powder above the cast tungsten carbide 2. The height h of the iron powder in the annular gap between the cover die 4 and the matrix 1 is 3-5 mm. In the high-temperature sintering, the cast tungsten carbide 2 (e.g., recovered cast tungsten carbide powder for secondary use) whose main component is tungsten (about 95.58%) is easily oxidized at a high temperature under an aerobic condition to form yellow tungsten trioxide, which is an impurity. The specific gravity of the tungsten trioxide is 7.16g/cm³The specific gravity of the iron powder is 7.8g/cm³Since the density of impurities floating from the gaps of the cast tungsten carbide 2 powder is less than that of iron, the impurities are not accumulated on the upper end surface of the cast tungsten carbide 2 but accumulated above the iron powder, so that the subsequent machining is facilitated. And removing all iron powder in the annular gap during machining. In order to prevent the liquid loss of the molten bonding alloy 5 during the subsequent sintering, the first outer cylindrical surface 11 part at the lower end of the substrate 1 and the second end of the cover die 4 are welded, sealed and fixed in a welding mode.

After the iron powder is put, a certain amount of bonding alloy 5 is put in proportion, and a certain amount of fluxing agent 8 is uniformly sprayed on the bonding alloy 5 in proportion. The fluxing agent 8 is a substance capable of reducing the melting point of the substance, and the fluxing agent 8 is most commonly applied to metallurgical technology, so that the metal can be smelted, welded and the like at a lower temperature. In metallurgy, its main role is to combine with impurities in minerals to form slag and separate from metals for smelting or refining purposes. In the present application, the flux 8 lowers the melting point of the binder alloy 5 to sufficiently melt the entire binder alloy, and the molten metal liquid decreases in viscosity with an increase in temperature and flows more easily, so that the molten metal liquid is more likely to enter the gap between the cast tungsten carbide 2, the wear-resistant material 3, and the base 1.

Specifically, the fluxing agent 8 may be anhydrous sodium tetraborate (chemical formula of Na)₂B₄O₇). The anhydrous sodium tetraborate is also called as a metal cleaning agent, and can clean the cast tungsten carbide 2, the wear-resistant part 3 and the matrix 1 and improve the bonding strength between the molten bonding alloy 5 liquid and the materials to be welded.

Specifically, the cast tungsten carbide 2, the bonding alloy 5 and the fluxing agent 8 are in percentage by weight: 1000:1200:1. Since the weight of the cast tungsten carbide 2 is the basis for the calculation of the amounts of the binder alloy 5 and the flux 8, the weight of the cast tungsten carbide 2 must be recorded clearly before and after the filling of the cast tungsten carbide 2 in order to calculate the actual use weight of the cast tungsten carbide 2.

Specifically, the binder alloy 5 is one or a mixture of any of copper-based alloy, nickel-based alloy, cobalt-based alloy and zinc-based alloy. For example, the formula (Ni-Mn-Cu-Zn) of a certain columnar small block bonding alloy 5 and the weight percentage content thereof are as follows: 8.0%, 5.0%, 52.0%, 35.0%.

In the sintering step, the sintering temperature is 960-1100 ℃, the bonding alloy 5 to be melted is soaked into the pores among the cast tungsten carbide 2, the wear-resistant part 3 and the matrix 1 in the annular gap from the cover die 4 and the positioning layer 6 in sequence, then the temperature is kept for 40-120 minutes, and then air cooling is carried out to prepare a moving ring blank; after sintering, the bonding strength among the cast tungsten carbide 2, the wear-resistant part 3 and the matrix 1 is more than or equal to 60 MPa.

Of course, the time for the heat preservation is not limited to the above example, and is mainly determined by the number of the workpieces in the furnace and the volume of the workpieces. Generally, the larger the number of workpieces and the larger the volume of the workpieces, the longer the heat preservation time is. And after the heat preservation is finished, taking out the moving ring blank for air cooling to obtain the moving ring blank.

After the sintering step is completed, a machining step may be performed. Specifically, when the machining step is executed, after the sintered moving ring blank is taken out of the sintering furnace and air-cooled to normal temperature, the moving ring blank is machined, so that the actual size of the moving ring reaches the design technical requirement.

Specifically, the machining comprises the following steps: rough turning (commonly called as a raking block) is carried out, rough machining is carried out on a moving ring blank, and certain machining allowance is reserved for each subsequent machining step; grinding, namely grinding the outer surface of the movable ring by using a diamond grinding wheel or a grinding head to ensure that the surfaces of the wear-resistant pieces 3 are in the same cylindrical surface and the surface roughness is reduced; and thirdly, finish turning, namely machining all dimensions of the movable ring to the design requirements according to the technical requirements by taking the surface of the wear-resistant part 3 as the reference.

In the second embodiment, a different base 1 is used from the first embodiment. In particular, in the second embodiment, the fifth 19 and sixth 20 outer cylindrical surfaces of the matrix 1 have a diameter much greater than the diameter of the first 11 or second 42 inner cylindrical surface of the die 4; in addition, the coverage area of the wear-resistant part 3 on the outer cylindrical surface of the moving ring finished product (shown in figure 3) only occupies a small part of the total area of the outer cylindrical surface of the moving ring, and the wear-resistant part 3 is positioned in the middle of the moving ring; whereas in the first embodiment the base body 1 is free of the fifth 19 and sixth 20 outer cylindrical surfaces; the coverage area of the wear-resistant part 3 on the outer cylindrical surface of the finished movable ring accounts for most of the total area of the outer cylindrical surface of the movable ring.

The first embodiment provides a mould 001 for producing a radially centred plain bearing ring as shown in figure 1, whereas the second embodiment provides a mould 002 or the third embodiment provides a mould 003 for producing both a radially centred plain bearing ring as shown in figure 1 and a radially centred plain bearing ring as shown in figure 3 (of the push-on rotary steerable system or downhole power drill type). The die 002 provided in the second embodiment is safer to manufacture the radial-righting sliding bearing moving ring shown in fig. 3 than the die 003 provided in the third embodiment, and the influence of thermal stress is less because the weld crater is farther away from the finished moving ring substrate 1. The fourth embodiment provides a mould 004 which is mainly used for manufacturing a radially-righting sliding bearing moving ring as shown in fig. 6.

Because the movable ring blank prepared by pressureless dipping and sintering can not be subjected to quenching and tempering heat treatment. The applicant found that: the hardness of the base body 1 after high-temperature sintering and air cooling is related to the time for reducing the temperature of the mould to normal temperature (10-30 ℃) after the mould is taken out of the high-temperature (960-1100 ℃) electric furnace, and the time influences the final hardness of the material of the moving ring base body 1.

For specific steps of the manufacturing method of the radial-centering sliding bearing moving ring provided by the present embodiment, reference may be made to the detailed description of the above embodiments, and details of the present application are not repeated herein.

Through verification, the brand-new manufacturing method for the radial centralizing sliding bearing moving ring is provided in the embodiment of the application, the hardness of the finished product matrix material and the service life of the radial centralizing sliding bearing can be improved, the machining difficulty and the manufacturing cost are reduced, the use requirement of a modern drilling downhole tool can be better met, and the popularization and the application are facilitated.

It should be noted that, in the description of the present application, the terms "first", "second", and the like are used for descriptive purposes only and for distinguishing similar objects, and no precedence between the two is intended or should be construed to indicate or imply relative importance. In addition, in the description of the present application, "a plurality" means two or more unless otherwise specified.

The above description is only a few embodiments of the present application, and those skilled in the art can make various changes or modifications to the embodiments of the present application without departing from the spirit and scope of the present application, based on the disclosure of the application document.

Claims

1. A mould for manufacturing a radial centralizing sliding bearing moving ring is characterized by comprising: a basal body, a cover die, a wear-resistant part and a cover plate,

the substrate is a hollow revolving body and is made of manganese-containing alloy steel;

the cover die is a hollow revolving body, the cover die is coaxially sleeved on the periphery of the base body, an annular space is formed between the inner wall of the cover die and the outer wall of the base body,

wear-resisting piece sets up on the inner wall of cover mould, wear-resisting piece's material includes: cemented carbide or/and polycrystalline diamond;

the upper end of the cover die is higher than the preset height of the base body, the cover plate is arranged at the upper end of the cover die, a preset containing space is formed among the cover die, the base body and the cover plate, and the containing space is used for placing a positioning layer, bonding alloy and fluxing agent.

2. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 1, wherein: the inner wall of the sleeve die is at least provided with a first inner cylindrical surface, a second inner cylindrical surface and a third inner cylindrical surface from bottom to top, the diameter of the first inner cylindrical surface is larger than that of the second inner cylindrical surface, and a first lower limiting part is formed between the first inner cylindrical surface and the second inner cylindrical surface; the diameter of the third inner cylindrical surface is larger than that of the second inner cylindrical surface, and an annular conical surface with a low middle part and a high periphery is formed between the third inner cylindrical surface and the second inner cylindrical surface.

3. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 2, wherein: the outer wall of the base body at least comprises a first outer cylindrical surface abutting against the first inner cylindrical surface and a second outer cylindrical surface matched with the second inner cylindrical surface; an annular gap is formed between the second inner cylindrical surface and the second outer cylindrical surface; the diameter of the first outer cylindrical surface is larger than that of the second outer cylindrical surface, a second lower limiting part is formed between the first outer cylindrical surface and the second outer cylindrical surface, and the first lower limiting part and the second lower limiting part are matched to form a limiting mechanism.

4. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 2, wherein: the diameter of the third inner cylindrical surface is equal to the diameter of the second inner cylindrical surface.

5. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 2, wherein: the upper end of the base body is a sealing end, and the lower end of the base body is an opening end; the upper end of the base body is provided with a cylinder cover, and the cylinder cover and the upper end of the base body are welded, sealed and fixed; and the periphery of the lower end of the base body is welded, sealed and fixed with the second end of the cover die.

6. A mold for manufacturing a radially-centered plain bearing rotating ring according to claim 3, wherein: the outer wall of the base body is also provided with a third outer cylindrical surface, the diameter of the third outer cylindrical surface is smaller than that of the second outer cylindrical surface, and a compensation ring is coaxially arranged on the outer sides of the third outer cylindrical surface and the second outer cylindrical surface.

7. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 6, wherein: a fourth outer cylindrical surface is arranged on the outer wall of the compensation ring, and a fourth inner cylindrical surface and a fifth inner cylindrical surface are arranged on the inner wall of the compensation ring; the fourth inner cylindrical surface is in clearance fit with the third outer cylindrical surface, and the fifth inner cylindrical surface is in clearance fit with the second outer cylindrical surface; a second upper limit part is formed between the fourth outer cylindrical surface and the second outer cylindrical surface; an annular gap is formed between the fourth outer cylindrical surface and the annular conical surface and between the fourth outer cylindrical surface and the third inner cylindrical surface and is used for accommodating the positioning layer; the compensation ring is welded and fixed with the upper end of the base body.

8. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 2, wherein: and the second inner cylindrical surface is provided with a groove.

9. The mold for manufacturing a radially-centered plain bearing rotating ring according to claim 1, wherein: the lower end of the cover die is fixedly, transitionally and fittingly welded with the periphery of the lower end of the base body to form a sealing end.

10. The mold for manufacturing a radially centering sliding bearing dynamic ring according to claim 1, wherein said cover plate is provided with ventilation holes.

11. The mold for manufacturing a radially-centered plain bearing dynamic ring according to claim 2, wherein a positioning portion for positioning the wear-resistant member is further provided on the second inner cylindrical surface.