A wear-resistant pump body and its manufacturing method

Abstract

The present invention discloses a wear-resistant pump body and a manufacturing method thereof. The pump body includes a lining body and a housing. The material of the lining body is combined silicon carbide ceramic. The lining body is provided with a cavity at the tongue separator part of the pump body, and a first pre-fired wear-resistant plate is embedded in the cavity. The material of the first pre-fired wear-resistant plate is silicon carbide or silicon nitride; the contours of the cavity and the first pre-fired wear-resistant plate are adapted to each other. The steps of the manufacturing method include fixing the first pre-fired wear-resistant plate with an organic glue coated on its surface at a position corresponding to the tongue separator of the pump body in the mold; pouring the mixture into the mold, and after the mixture hardens, obtaining a blank of the lining body embedded with the first pre-fired wear-resistant plate, and drying it; heating until the organic glue is ablated; finally combining the lining body, the housing and the first pre-fired wear-resistant plate into an integral body. The wear-resistant pump body and the manufacturing method thereof provided by the present invention can extend the service life of the pump body, and have stable quality and are easy to produce and process.

Description

Technical Field

[0001] The present invention relates to the field of rotary power pump equipment, and particularly to a wear-resistant pump body and a manufacturing method thereof. Background Art

[0002] In industries such as ore dressing and smelting, centrifugal pumps are often used to transport some abrasive solid-liquid two-phase flows, and wear-resistant pumps are often selected at this time. Common wear-resistant pumps are made of wear-resistant alloys such as Cr26 and Cr15Mo3 or wear-resistant materials such as rubber. Pumps made of these wear-resistant materials are difficult to meet the use requirements under many working conditions.

[0003] As is well known, wear-resistant ceramics have much higher wear resistance than wear-resistant alloys. For example, silicon carbide ceramics, silicon nitride ceramics, alumina ceramics, duplex sintered ceramics, etc., and their wear resistance can be several times or even dozens of times higher than that of wear-resistant alloys. Documents such as CN108533501A disclose some technical solutions of wear-resistant pump bodies made of ceramic materials. From the current technical situation, the ceramic materials for manufacturing wear-resistant pump bodies are mainly several materials such as alumina (Al2O3), silicon nitride (Si3N4), silicon carbide (SiC), and duplex sintered ceramics. Among them, alumina ceramics have relatively poor wear resistance and are not easy to be made into large sizes, and are significantly limited in the fields where wear-resistant pumps have requirements for both wear resistance and large size; due to process reasons, the cost of silicon nitride is relatively high and it is also difficult to apply; silicon carbide ceramics have excellent wear resistance and relatively low cost, but due to process reasons, it is difficult to be made into large sizes, which also limits its application; combined silicon carbide ceramics are a kind of material composed of silicon carbide as the main phase and a bonding phase combined. Among them, the main phase silicon carbide has good wear resistance and low cost; the role of the bonding phase is to bond the particles of the main phase into one body. According to different bonding phases, there are various types of combined silicon carbide ceramics. The common ones are: silicon nitride-bonded silicon carbide, oxide-bonded silicon carbide, oxynitride-bonded silicon carbide, sialon-bonded silicon carbide, etc. The microstructures and manufacturing processes of the above several types of combined silicon carbide ceramics are similar. The microstructure is that the bonding phase wraps the main phase particles in a network shape, where the weight ratio of silicon carbide is about 70-90%, and the weight ratio of the bonding phase is about 10-30%. Since the above several types of combined silicon carbide ceramics hardly change in size during the sintering process, and the network-shaped bonding phase contains a certain number of tiny pores. These tiny pores not only help to avoid defects such as cracking during sintering, are beneficial to the large size of the pump body, but also help the pump body absorb the impact energy during operation and improve the impact resistance of the material. Therefore, combined silicon carbide ceramics have developed rapidly in the field of wear-resistant pumps in recent years. They not only have relatively low cost but also good wear resistance, and can currently be used to manufacture pump bodies of larger sizes.

[0004] The manufacturing process of silicon nitride bonded silicon carbide is as follows: Mix silicon carbide particles accounting for about 70 - 75% by weight, silicon powder and a binder. After molding and drying, place it in a nitriding furnace and heat it to 1410 - 1430°C. Then introduce high-purity nitrogen. The nitrogen reacts with the silicon powder to form silicon nitride. The formed silicon nitride is in a network shape to coat the silicon carbide particles and form a bonded body with a certain strength. Sometimes, to improve certain properties, a small amount (generally not exceeding 5%) of alumina, silica, mullite, etc. is added to the mixture.

[0005] The manufacturing process of oxide bonded silicon carbide is as follows: Mix silicon carbide particles accounting for about 70 - 75% by weight, silicon powder and a binder (sometimes a small amount of alumina, calcium oxide, mullite, etc. is added to improve certain properties). After molding and drying, place it in a sintering furnace and heat it to 1410 - 1430°C. Oxygen in the air reacts with the silicon powder to form silicon dioxide. The formed silicon dioxide is in a network shape to coat the silicon carbide particles and form a bonded body with a certain strength.

[0006] The manufacturing process of oxynitride bonded silicon carbide is as follows: Mix silicon carbide particles, silicon powder, silica, clay and a binder. After molding and drying, place it in a sintering furnace and heat it to 1410 - 1430°C. Then introduce nitrogen to react to form oxynitride which is in a network shape to coat the silicon carbide particles and form a bonded body with a certain strength.

[0007] The manufacturing process of sialon bonded silicon carbide is as follows: Mix silicon carbide particles, silicon powder, alumina and a binder. After molding and drying, place it in a sintering furnace and heat it to 1410 - 1430°C. Then introduce nitrogen to react to form sialon which is in a network shape to coat the silicon carbide particles and form a bonded body with a certain strength.

[0008] However, when the above several kinds of silicon carbide bonded pump bodies are applied to the working conditions where there are large particles in the medium, the effect is poor. Especially at the tongue of the pump body, the wear rate is more than three times that of other parts. This situation results in the service life of the pump body being much lower than expected. The reason is that the wear resistance of the binding phase in the silicon carbide bonded ceramic is much worse than that of the main phase. When the binding phase is worn, the main phase particles will fall off due to the lack of the holding of the binding phase. To solve this problem, CN208950968U discloses a wear-resistant silicon carbide ceramic volute, as Figure 19 shown, including a housing 1 and a wear-resistant inner lining layer 2 fixedly arranged on the inner wall of the housing 1. A wear-resistant block 4 is arranged at the tongue 3 of the wear-resistant inner lining layer 2. In a preferred solution, the wear-resistant inner lining layer is made of silicon carbide ceramic material, and the wear-resistant block is made of silicon carbide ceramic, silicon nitride bonded silicon carbide ceramic or silicon oxide bonded silicon carbide ceramic. This solution has the following problems:

[0009] 1) Fixing problem of wear-resistant block: The reason for setting the wear-resistant block 4 is that its wear resistance is significantly higher than that of the wear-resistant inner lining layer 2. In this solution, the wear-resistant block is set at the tongue of the wear-resistant inner lining layer 2, and the tongue 3 is a protruding part of the wear-resistant inner lining layer 2. Fixing the wear-resistant block 4 at this place is not only difficult but also unreliable; even if it can be reliably fixed during manufacturing, during use, since the wear resistance of the wear-resistant inner lining layer 2 is significantly lower than that of the wear-resistant block 4, when the wear-resistant inner lining layer around the wear-resistant block 4 is worn, the reliability of fixing the wear-resistant block 4 becomes a problem. Once the wear-resistant block 4 falls off, the service life of the pump body will be much lower than expected.

[0010] 2) Placement problem of wear-resistant block: The wear-resistant block 4 is placed after the wear-resistant inner lining layer 2 is sintered, which requires a suitable gap between the wear-resistant inner lining layer 2 and the wear-resistant block 4. If the gap is too small, it is difficult to place the wear-resistant block 4 in place; if the gap is too large, the resin in the gap is easily worn and the wear-resistant block will fall off. Since the shape of the tongue part where the wear-resistant block 4 is located is complex, it is difficult for both the wear-resistant block 4 and the inner lining layer 2 to be machined mechanically to ensure the fitting accuracy between the two to ensure a small fitting gap.

[0011] 3) The larger the size of the wear-resistant block 4, the more complex the shape of the groove for placing the wear-resistant block 4 on the inner lining 2, and the greater the manufacturing difficulty.

[0012] 4) The wear-resistant block 4 is placed in the groove after the inner lining 2 is sintered. Obviously, if it is not bonded with an adhesive, the wear-resistant block 4 will come out of the groove towards the flow-through surface direction, which makes the fixing reliability of the wear-resistant block 4 poor.

[0013] In summary, the existing ceramic pump body has problems of poor reliability, unstable quality, and great manufacturing process difficulty. Summary of the Invention

[0014] The purpose of the present invention is to provide a wear-resistant pump body and its manufacturing method, which can extend the service life of the pump body, and has stable quality and is easy to produce and process.

[0015] To achieve the above purpose, the present invention provides a wear-resistant pump body, including an inner lining body and a housing. The material of the inner lining body is combined silicon carbide ceramic. The inner lining body is provided with a cavity at the tongue part of the pump body, and a first pre-sintered wear-resistant plate is embedded in the cavity. The material of the first pre-sintered wear-resistant plate is silicon carbide or silicon nitride; the contours of the cavity and the first pre-sintered wear-resistant plate are adapted to each other.

[0016] As a further improvement of the present invention, a buffer layer is provided between the housing and the inner lining body, and the buffer layer contains a first adhesive; the first adhesive contains wear-resistant particles, and the wear-resistant particles include one or any combination of silicon carbide, corundum, garnet, silicon nitride, and quartz.

[0017] As a further improvement of the present invention, the axial dimension b1 of the first pre-fired wear-resistant plate along the pump body is greater than the width b of the outlet of the impeller supporting the pump body.

[0018] As a further improvement of the present invention, the contour dimension of the first pre-fired wear-resistant plate on a section farther from the flow-through surface is greater than its contour dimension on another parallel section closer to the flow-through surface.

[0019] As a further improvement of the present invention, part or all of the outer surface of the first pre-fired wear-resistant plate is adhesively bonded to the buffer layer as a whole.

[0020] As a further improvement of the present invention, part or all of the outer surface or inner surface of the first pre-fired wear-resistant plate is locally or entirely covered with a combined silicon carbide ceramic layer integrally formed with the inner lining body.

[0021] As a further improvement of the present invention, the first pre-fired wear-resistant plate is formed by splicing at least two ceramic plates.

[0022] As a further improvement of the present invention, an air gap is provided at the joint between the hole cavity and the first pre-fired wear-resistant plate, the average width of the air gap does not exceed 1 mm, and a second adhesive is filled in the air gap; the second adhesive contains wear-resistant particles.

[0023] As a further improvement of the present invention, the inner lining body is provided with a groove at the position of the radial projection of the outlet of the impeller supporting the pump body, the groove extends from the edge of the hole cavity along the rotation direction of the impeller to the diffuser pipe, and a second pre-fired wear-resistant plate is embedded in the groove.

[0024] As a further improvement of the present invention, the axial dimension b2 of the groove along the pump body is greater than the width b of the outlet of the impeller supporting the pump body; the second pre-fired wear-resistant plate is formed by splicing at least two ceramic plates made of silicon carbide or silicon nitride; the second pre-fired wear-resistant plate is adhesively bonded in the groove by a third adhesive; the third adhesive contains wear-resistant particles.

[0025] To achieve the above object, the present invention also provides a manufacturing method of a wear-resistant pump body, including the following steps:

[0026] 1) Manufacture the first pre-fired wear-resistant plate;

[0027] 2) Coat the surface of the first pre-fired wear-resistant plate with an organic glue and harden the organic glue;

[0028] 3) Fix the first pre-fired wear-resistant plate coated with the organic glue between the outer mold and the inner mold at the position corresponding to the pump body tongue;

[0029] 4) Mix silicon carbide particles, silicon metal powder, and binder in proportion to form a uniform mixture, and pour the mixture into the mold composed of the outer mold and the inner mold;

[0030] 5) After the mixture hardens, remove the mold to obtain a green body of the inner lining body embedded with the first pre-fired wear-resistant plate, and dry it;

[0031] 6) Place the green body of the inner lining body embedded with the first pre-fired wear-resistant plate into a sintering furnace, heat it to 300°C - 500°C, and ablate the organic glue;

[0032] 7) Introduce high-purity nitrogen and heat it to 1410 - 1450°C to obtain the inner lining body embedded with the first pre-fired wear-resistant plate; or introduce air and heat it to 1410 - 1450°C to obtain the inner lining body embedded with the first pre-fired wear-resistant plate;

[0033] 8) Place the inner lining body embedded with the first pre-fired wear-resistant plate into the outer shell for positioning, and inject the mixture forming the buffer layer between the two; after the mixture hardens, form the buffer layer, and integrate the inner lining body, the outer shell, and the first pre-fired wear-resistant plate into a whole.

[0034] Beneficial effects

[0035] Compared with the prior art, the advantages of the wear-resistant pump body and its manufacturing method of the present invention are as follows:

[0036] 1. Adopting the manufacturing method provided by this technical solution, placing the first pre-fired wear-resistant plate in the mold for casting the inner lining body can cast the inner lining body and the first pre-fired wear-resistant plate into a whole, so that the hole cavity on the inner lining body naturally forms a contour adapted to the first pre-fired wear-resistant plate. It is possible to ensure that the first pre-fired wear-resistant plate and the hole cavity are adapted to each other and have a small fit clearance without mechanical cutting of the first pre-fired wear-resistant plate and the hole cavity, thereby avoiding the phenomenon that the fit clearance is too large in the prior art, resulting in easy wear of the resin and falling off of the wear-resistant block.

[0037] 2. The material of the inner lining body is silicon carbide ceramic in combination. Due to the presence of an appropriate amount of tiny pores in this material, it is not only easy to make the pump body larger, but also has good impact resistance and low cost.

[0038] 3. The first pre-fired wear-resistant plate is silicon carbide or silicon nitride ceramic, such as reaction-sintered silicon carbide, pressureless-sintered silicon carbide, reaction-sintered silicon nitride, hot-pressed sintered silicon nitride, etc. Its wear resistance is more than 3 - 5 times higher than that of silicon carbide ceramic in combination. If it can be reliably set in severely worn parts such as the cut-off tongue, the overall life of the pump body will be greatly improved.

[0039] 4. Since the outer dimension of the first pre-sintered wear-resistant plate is much smaller than that of the inner lining body, it is not only easy to manufacture with silicon carbide ceramics or silicon nitride ceramics, but also the cost increase is less.

[0040] 5. When part or all of the outer surface of the first pre-sintered wear-resistant plate is bonded to the buffer layer to form an integral body, there is a large bonding area between the first pre-sintered wear-resistant plate and the buffer layer, and this bonding surface will not be subject to erosion wear, and its bonding is more reliable than the prior art.

[0041] 6. In the process of manufacturing the pump body according to the technical solution provided, if the thickness of the first pre-sintered wear-resistant plate is less than the thickness of the inner lining body, its outer surface or inner surface may be partially or completely covered by the casting material during the casting process. Obviously, this kind of covering will not have a great impact on the performance of the pump body. Therefore, it is allowed that part or all of the outer surface or inner surface of the first pre-sintered wear-resistant plate is covered and combined with the silicon carbide ceramic layer of the integral forming structure of the inner lining body, which is beneficial to reducing the process difficulty and manufacturing cost.

[0042] 7. The hole cavity is formed naturally during the casting process. The increase in the size of the first pre-sintered wear-resistant plate and the increase in the complexity of its shape will not increase the manufacturing difficulty of the hole cavity. Therefore, the first pre-sintered wear-resistant plate can be made larger, and it is easy to make its axial dimension b1 along the pump body larger than the width b of the outlet of the supporting impeller, so that the first pre-sintered wear-resistant plate has better wear resistance; while in the prior art, when the axial dimension of the wear-resistant plate 4 is larger, it is difficult to place the wear-resistant plate on the cut-off tongue, so the wear resistance is poor.

[0043] 8. Since the first pre-sintered wear-resistant plate is restricted in the hole cavity, it can only be disengaged from the flow-through surface direction; if a sectional structure is provided on the first pre-sintered wear-resistant plate to prevent it from disengaging from the hole cavity to the flow-through surface direction, for example, as long as the contour dimension of a section away from the flow-through surface is larger than the contour dimension of a parallel section close to the flow-through surface, the first pre-sintered wear-resistant plate is like a wedge with a large inner and small outer shape embedded in the hole cavity and is restricted by the hole cavity contour and cannot be disengaged from the flow-through surface direction. Therefore, the fixation of the first pre-sintered wear-resistant plate of the present invention has, in addition to the adhesive force of the adhesive, the wedge force at the joint of the inner lining body and the first pre-sintered wear-resistant plate, and the reliability is greatly improved.

[0044] 9. The pre-sintered wear-resistant plate refers to a ceramic plate that has been sintered and formed before being fixed in a predetermined position. These two materials, silicon carbide ceramics and silicon nitride ceramics, not only have much better wear resistance than the combined silicon carbide ceramics, but also their thermal expansion coefficients are relatively close to those of the combined silicon carbide ceramics. During the sintering process of the inner lining body, it is not easy to cause the inner lining body or the first pre-sintered wear-resistant plate to crack due to expansion or contraction reasons. Therefore, using these two materials to manufacture the first pre-sintered wear-resistant plate is also beneficial to improving the qualified rate of the pump body.

[0045] 10. Before pouring the inner liner body, there are two purposes for coating a certain thickness of organic glue on the surface of the first pre-sintered wear-resistant plate. One is that the organic glue is beneficial to bonding the first pre-sintered wear-resistant plate and the blank of the inner liner body into a whole, so that the blank of the inner liner body embedded with the first pre-sintered wear-resistant plate has better strength. The other is that the organic glue can be burned and vaporized before sintering, so that an air gap with a suitable width is formed at the joint of the first pre-sintered wear-resistant plate and the blank of the inner liner body due to the vaporization of the organic glue, avoiding cracking and damage of the blank of the inner liner body or the first pre-sintered wear-resistant plate during the sintering process due to the slight difference in the thermal expansion coefficients between the two.

[0046] 11. For the pump body manufactured by the method provided in this solution, without mechanically cutting the hole cavity and the first pre-sintered wear-resistant plate, it is easy to ensure that there is an air gap with an average width not exceeding 1 mm at the joint of the two. This small gap makes the second adhesive impregnated therein not easily worn, which is beneficial to improving the fixing reliability of the first pre-sintered wear-resistant plate.

[0047] 12. The radial part at the outlet of the impeller is the most severely worn part. In addition to the tongue part, the second pre-sintered wear-resistant plate made of silicon carbide or silicon nitride is extended along the rotation direction of the impeller to the diffuser pipe part. This can significantly improve the service life of the pump body. The groove provided on the inner liner body can provide an installation space for the second pre-sintered wear-resistant plate.

[0048] 13. The axial dimension b2 of the second pre-sintered wear-resistant plate along the pump body is greater than the width b of the outlet of the supporting impeller to ensure the service life of the pump body. Since the size of the second pre-sintered wear-resistant plate is large, the second pre-sintered wear-resistant plate is composed of multiple ceramic plates joined together, which can reduce its manufacturing difficulty and cost.

[0049] Through the following description and in combination with the accompanying drawings, the present invention will become clearer. These drawings are used to explain the embodiments of the present invention. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0051] Figure 1 It is a cross-sectional view of the wear-resistant pump body in Embodiment 1;

[0052] Figure 2 It is a three-dimensional view of the combination of the inner liner body and the first pre-sintered wear-resistant plate in Embodiment 1;

[0053] Figure 3Cross-sectional view of the combination of the inner liner body and the first pre-fired wear-resistant plate in Embodiment 1;

[0054] Figure 4 Stereoscopic cross-sectional view of the inner liner body after removing the first pre-fired wear-resistant plate in Embodiment 1;

[0055] Figure 5 Stereogram of the first pre-fired wear-resistant plate in Embodiment 1;

[0056] Figure 6 For Figure 5 A - A cross-sectional view;

[0057] Figure 7 For Figure 5 B - B cross-sectional view;

[0058] Figure 8 Relationship diagram of relevant dimensions when the impeller is installed in the pump body in Embodiment 1;

[0059] Figure 9 Schematic diagram of the casting and molding of the inner liner body in Embodiment 1;

[0060] Figure 10 Cross-sectional view of the wear-resistant pump body in Embodiment 2;

[0061] Figure 11 For Figure 10 C - C cross-sectional view;

[0062] Figure 12 Cross-sectional view of the inner liner body in Embodiment 2;

[0063] Figure 13 Stereogram of the first pre-fired wear-resistant plate in Embodiment 3;

[0064] Figure 14 Cross-sectional view of the wear-resistant pump body in Embodiment 4;

[0065] Figure 15 Schematic diagram of the molding of the inner liner body in Embodiment 4;

[0066] Figure 16 Cross-sectional view of the wear-resistant pump body in Embodiment 5;

[0067] Figure 17 Schematic diagram of the forming of the inner liner body in Embodiment 5;

[0068] Figure 18 Cross-sectional view of the wear-resistant pump body in Embodiment 6;

[0069] Figure 19 Cross-sectional view of the solution of CN208950968U. Detailed implementation manners

[0070] Reference is now made to the accompanying drawings to describe embodiments of the present invention.

[0071] Embodiment 1

[0072] The specific implementation manner of the present invention is as Figures 1 to 9 shown. A wear-resistant pump body includes a lining body 300 and a housing 100. The material of the lining body 300 is silicon carbide ceramic in combination. The lining body 300 is provided with a cavity 301 at the tongue part of the pump body. A first pre-fired wear-resistant plate 400 is embedded in the cavity 301. The material of the first pre-fired wear-resistant plate 400 is silicon carbide or silicon nitride. The contours of the cavity 301 and the first pre-fired wear-resistant plate 400 are adapted to each other. A buffer layer 200 is provided between the housing 100 and the lining body 300. The buffer layer 200 contains a first adhesive. The first adhesive contains wear-resistant particles, and the wear-resistant particles include one or any combination of silicon carbide, corundum, garnet, silicon nitride, and quartz. The housing 100 can be made of a metal material.

[0073] The silicon carbide ceramic in combination used for the above-mentioned lining body 300 is one of silicon nitride bonded silicon carbide ceramic, oxide bonded silicon carbide ceramic, oxynitride bonded silicon carbide ceramic, and sialon bonded silicon carbide ceramic.

[0074] In this embodiment, the material of the lining body 300 is silicon nitride bonded silicon carbide, and the material of the first pre-fired wear-resistant plate 400 is reaction-sintered silicon carbide. The main components of the buffer layer 200 are resin and wear-resistant particles. As Figure 4 shown, the cavity 301 is a through hole. The outer surface of the first pre-fired wear-resistant plate 400 is bonded to the buffer layer 200 by the adhesive in the buffer layer 200, and the contour of the cavity 301 is adapted to the contour of the first pre-fired wear-resistant plate 400.

[0075] The contour dimensions of the first pre-fired wear-resistant plate 400 on a cross-section farther from the flow-through surface are larger than its contour dimensions on another parallel cross-section closer to the flow-through surface. In this embodiment, as Figure 5 shown, the A-A plane and the B-B plane are parallel, and the A-A plane is farther from the flow-through surface than the B-B plane. As Figure 6 、 Figure 7 shown, the longitudinal contour dimension L1 of the first pre-fired wear-resistant plate 400 on the A-A plane is larger than the longitudinal contour dimension L2 on the B-B plane, and the transverse contour dimension L3 on the A-A plane is larger than the transverse contour dimension L4 on the B-B plane.

[0076] Since the contour of the hole cavity 301 on the inner lining body 300 is adapted to the contour of the first pre-fired wear-resistant plate 400, the contour dimension of the hole cavity 301 on the inner lining body 300 in the B-B plane must be smaller than the contour dimension of the first pre-fired wear-resistant plate 400 in the A-A plane. This constrains the first pre-fired wear-resistant plate 400 by the hole cavity 301 and prevents it from moving towards the flow-through surface direction. Therefore, even without the action of the adhesive in this embodiment, the first pre-fired wear-resistant plate 400 will not fall off from the hole cavity 300. During the subsequent fabrication of the pump body, the second adhesive infiltrated into the air gap will further fix the first pre-fired wear-resistant plate 400, making the fixation of the first pre-fired wear-resistant plate 400 much more reliable than in the prior art. In this embodiment, the first adhesive and the second adhesive are of the same material, both being epoxy resin. In addition to the second adhesive, the buffer layer 200 also contains wear-resistant particles, and the wear-resistant particles are silicon carbide.

[0077] Figure 8 It is a schematic diagram of the relative position relationship between the pump body and the supporting impeller after assembly. As can be seen from the figure, the axial dimension b1 of the first pre-fired wear-resistant plate 400 along the pump body is greater than the outlet width dimension b of the supporting impeller 500, so that the severely eroded part at the outlet of the impeller 500 at the tongue of the pump body can be completely covered by the first pre-fired wear-resistant plate 400. And the inner lining body 300 at the joint parts on both axial sides of the first pre-fired wear-resistant plate 400 is not directly scoured by the particles at the outlet of the impeller 500 because it is outside the outlet projection of the impeller 500, and its service life can be significantly improved. This is beneficial to preventing the first wear-resistant plate 400 from losing restraint and falling off due to the rapid wear at the joint of the inner lining body 300. Among them, the impeller outlet width refers to the axial distance between the impeller shroud and the impeller disc at the outlet position.

[0078] In this embodiment, the average size of the air gap between the first pre-fired wear-resistant plate 400 and the hole cavity 301 is 0.2 mm. This size can prevent the second adhesive infiltrated into it from being worn. To further improve the wear resistance of the second adhesive, wear-resistant particles with a particle size of about 0.05 mm can be added to it.

[0079] Figure 9 It is a schematic diagram of the casting of the inner lining body. In Figure 9 , the first pre-fired wear-resistant plate 400 is fixed at the corresponding positions of the outer mold 601 and the inner mold 602 for casting the inner lining. The mixed silicon nitride bonded silicon carbide mixture is injected into the mold from the pouring hole 6011 to fill the mold with the mixture. After the mixture hardens, the mold is removed, and the first pre-fired wear-resistant plate 400 is embedded in the blank of the inner lining body 300. The blank of the inner lining body 300 will naturally form a hole cavity 301 adapted to the contour of the first pre-fired wear-resistant plate 400 in this process.

[0080] The specific implementation steps of the manufacturing method of the wear-resistant pump body in this embodiment are as follows:

[0081] 1) Manufacture the blank of the first pre-sintered wear-resistant plate 400;

[0082] 2) Sinter the first pre-sintered wear-resistant plate 400 in a vacuum furnace;

[0083] 3) Coat the surface of the sintered first pre-sintered wear-resistant plate 400 with an organic glue of appropriate thickness (generally 0.2 - 1 mm), and harden the organic glue;

[0084] 4) Fix the first pre-sintered wear-resistant plate 400 coated with organic glue at the corresponding positions of the outer mold 601 and the inner mold 602;

[0085] 5) Mix silicon carbide particles, metallic silicon powder, and binder in proportion to form a uniform mixture, and pour the mixture into the mold;

[0086] 6) Demold after the mixture hardens;

[0087] 7) Dry the blank of the inner lining body 300 embedded with the first pre-sintered wear-resistant plate 400;

[0088] 8) Put the blank of the inner lining body 300 embedded with the first pre-sintered wear-resistant plate 400 into a sintering furnace, heat it to 300 - 500 °C, ablate the organic glue, and form an air gap of 0.2 - 1 mm between the first pre-sintered wear-resistant plate 400 and the inner lining body 300;

[0089] 9) Pass in high-purity nitrogen, heat it to 1410 - 1450 °C, and obtain the inner lining body 300 embedded with the first pre-sintered wear-resistant plate 400; in this embodiment, the high-purity nitrogen passed in is heated to about 1430 °C;

[0090] Or pass in air, heat it to 1410 - 1450 °C, and obtain the inner lining body 300 embedded with the first pre-sintered wear-resistant plate 400. In this embodiment, the air passed in is heated to about 1430 °C;

[0091] 10) Install the inner lining body 300 embedded with the first pre-sintered wear-resistant plate 400 in the outer shell 100 for positioning, inject the mixture of the buffer layer 200 between the two, form the buffer 200 after the mixture hardens, and combine the inner lining body 300, the outer shell 100, and the first pre-sintered wear-resistant plate 400 into a whole;

[0092] 11) Infiltrate a second adhesive into the air gap between the first pre-sintered wear-resistant plate 400 and the inner lining body 300; cure the second adhesive.

[0093] Example 2

[0094] As Figures 10 to 12As shown, the difference from Embodiment 1 is that the material of the first pre-fired wear-resistant plate 400 is hot-pressed sintered silicon nitride, and a second pre-fired wear-resistant plate 700 made of reaction-sintered silicon carbide is also provided on the inner lining body 300 made of oxide-bonded silicon carbide. From Figure 10 , 11 it can be seen that the second pre-fired wear-resistant plate 700 extends along the edge of the first pre-fired wear-resistant plate 400 in the rotation direction of the impeller ( Figure 10 shown as the counterclockwise direction) towards the diffuser tube. In this embodiment, the extending angle of the second pre-fired wear-resistant plate 700 is about 160 degrees. In some embodiments with light wear, the extending angle of the second pre-fired wear-resistant plate 700 can also be reduced to 10 - 30 degrees. The axial dimension b2 of the second pre-fired wear-resistant plate 400 is greater than the width dimension b of the outlet of the impeller 500. The second pre-fired wear-resistant plate 700 is composed of 7 ceramic plates joined together, and a groove 302 for accommodating the second pre-fired wear-resistant plate 700 is provided on the inner lining body 300. The second pre-fired wear-resistant plate 700 is bonded in the groove 302 through a third adhesive. In this embodiment, the first adhesive is vinyl resin, and the second and third adhesives are epoxy resins. The wear-resistant particles contained in the first, second, and third adhesives include one or any combination of silicon carbide, corundum, garnet, silicon nitride, and quartz.

[0095] Embodiment 3

[0096] As Figure 13 shown, the difference from Embodiment 1 is that the first pre-fired wear-resistant plate 400 is composed of two non-pressure sintered silicon carbide ceramic plates joined together, and the two ceramic plates are symmetrically arranged. The material of the inner lining body is silicon carbide ceramic bonded with oxynitride, or sialon-bonded silicon carbide ceramic can also be selected. Its processing process is basically the same as that of Embodiment 1, and the specific manufacturing process will not be described here.

[0097] Embodiment 4

[0098] As Figure 14 and Figure 15 shown, the difference from Embodiment 1 is that the outer surface of the first pre-fired wear-resistant plate 400 is partially or entirely bonded to the buffer layer 200. The inner surface of the first pre-fired wear-resistant plate 400 is partially or entirely covered with a silicon carbide ceramic layer integrally formed with the inner lining body 300, specifically a silicon nitride-bonded silicon carbide material layer. In Figure 15In the schematic diagram of the pouring in this embodiment, the thickness of the first pre-sintered wear-resistant plate 400 is less than that of the inner lining body 300. When the first pre-sintered wear-resistant plate 400 is fixed at the corresponding position of the outer mold 601 for pouring the inner lining, the pouring mixture will partially or completely cover the inner surface of the first pre-sintered wear-resistant plate 400, and a covering layer integrally formed with the inner lining body 300 will be formed after sintering. Obviously, this structure can reduce the dimensional accuracy requirements of the mold and the first pre-sintered wear-resistant plate 400 and reduce the manufacturing cost on the premise of not significantly affecting the performance.

[0099] Example 5

[0100] As Figure 16 and Figure 17 shown, the difference from Example 4 is that the inner surface of the first pre-sintered wear-resistant plate 400 is partially or completely covered with a silicon nitride-bonded silicon carbide material layer integrally formed with the inner lining body 300. In the schematic diagram of the pouring of the inner lining body in this embodiment shown in Figure 17 , the thickness of the first pre-sintered wear-resistant plate 400 is less than that of the inner lining body 300. During pouring, the first pre-sintered wear-resistant plate 400 is fixed on the inner mold 602 for pouring the inner lining. When pouring, the pouring mixture will partially or completely cover the outer surface of the first pre-sintered wear-resistant plate 400, and a covering layer integrally formed with the inner lining body 300 will be formed after sintering. This structure can also reduce the accuracy of the mold and the first pre-sintered wear-resistant plate 400 and reduce the manufacturing cost on the premise of not significantly reducing the performance.

[0101] Example 6

[0102] As Figure 18 shown, this example is substantially the same as Example 4 and Example 5, the difference being that the inner surface and the outer surface of the first pre-sintered wear-resistant plate 400 are partially or completely covered with a silicon nitride-bonded silicon carbide material layer integrally formed with the inner lining body 300. During the manufacturing process of Example 4 or Example 5, due to certain reasons, the first pre-sintered wear-resistant plate 400 may not be firmly fixed on the mold, resulting in the pouring material covering the inner surface and the outer surface of the first pre-sintered wear-resistant plate 400 during forming, and a covering layer integrally formed with the inner lining body 300 will be formed on the inner surface and the outer surface of the first pre-sintered wear-resistant plate 400 after sintering. This structure, like Example 4 and Example 5, can reduce the accuracy of the mold and the first pre-sintered wear-resistant plate 400 and reduce the manufacturing cost on the premise of not significantly reducing the performance.

[0103] Obviously, in the above examples, the hole cavity 301 can be a through hole, a blind hole, or a chamber completely enclosed on the outside under different manufacturing conditions. Therefore, regardless of the condition of the hole cavity 301, it is within the coverage of the present invention.

[0104] The present invention has been described in conjunction with the preferred embodiments, but the present invention is not limited to the disclosed embodiments above, and should cover various modifications and equivalent combinations made according to the essence of the present invention.

Claims

1. A wear-resistant pump body, comprising a lining body (300) and a housing (100), characterized in that, The material of the inner lining body (300) is bonded silicon carbide ceramic. The inner lining body (300) is provided with a hole cavity (301) at the tongue position of the pump body. A first pre-fired wear-resistant plate (400) is embedded in the hole cavity (301). The material of the first pre-fired wear-resistant plate (400) is silicon carbide or silicon nitride. The contours of the hole cavity (301) and the first pre-fired wear-resistant plate (400) are adapted to each other. The dimension b1 of the first pre-fired wear-resistant plate (400) along the axial direction of the pump body is greater than the width b of the outlet of the impeller supporting the pump body. The contour dimension of the first pre-fired wear-resistant plate (400) on a section farther from the flow-through surface is greater than its contour dimension on another parallel section closer to the flow-through surface. A buffer layer (200) is provided between the outer shell (100) and the inner lining body (300). The buffer layer (200) contains a first adhesive. The first adhesive contains wear-resistant particles, and the wear-resistant particles include one or any combination of silicon carbide, corundum, garnet, silicon nitride, and quartz.

2. The wear-resistant pump body according to claim 1, characterized in that, Part or all of the outer surface of the first pre-fired wear-resistant plate (400) is bonded to the buffer layer (200) integrally.

3. A wear-resistant pump body according to claim 1 or 2, characterized in that, Partially or entirely covering the outer surface or the inner surface of the first pre-fired wear-resistant plate (400) is a bonded silicon carbide ceramic layer integrally formed with the inner lining body (300).

4. A wear-resistant pump body according to claim 1 or 2, characterized in that, The first pre-fired wear-resistant plate (400) is formed by splicing at least two ceramic plates.

5. A wear-resistant pump body according to claim 1 or 2, characterized in that, An air gap is provided at the joint between the hole cavity (301) and the first pre-fired wear-resistant plate (400). The average width of the air gap does not exceed 1 mm, and a second adhesive is filled in the air gap.

6. A wear-resistant pump body according to claim 1 or 2, characterized in that, The inner lining body (300) is provided with a groove (302) at the position of the radial projection of the outlet of the impeller supporting the pump body. The groove (302) extends from the edge of the hole cavity (301) along the rotation direction of the impeller to the diffuser pipe. A second pre-fired wear-resistant plate (700) is embedded in the groove (302).

7. A wear-resistant pump body according to claim 6, characterized in that, The dimension b2 of the groove (302) along the axial direction of the pump body is greater than the width b of the outlet of the impeller supporting the pump body. The second pre-fired wear-resistant plate (700) is formed by splicing at least two ceramic plates made of silicon carbide or silicon nitride. The second pre-fired wear-resistant plate (700) is bonded in the groove (302) through a third adhesive. The third adhesive contains wear-resistant particles.

8. The manufacturing method of an abrasion-resistant pump body according to claim 1, characterized in that Including the following steps: 1) Manufacturing the first pre-fired wear-resistant plate (400); the contour dimension of the first pre-fired wear-resistant plate (400) on a section farther from the flow-through surface is greater than its contour dimension on another parallel section closer to the flow-through surface; 2) Coating the surface of the first pre-fired wear-resistant plate (400) with an organic glue and hardening the organic glue; 3) Fixing the first pre-fired wear-resistant plate (400) coated with the organic glue at the position corresponding to the tongue of the pump body between the outer mold (601) and the inner mold (602); 4) Mixing silicon carbide particles, metal silicon powder, and binder in proportion to form a uniform mixture, and pouring the mixture into the mold composed of the outer mold (601) and the inner mold (602); 5) After the mixture hardens, remove the mold to obtain a blank of the inner liner body (300) embedded with the first pre-fired wear-resistant plate (400), and dry it. 6) Heat the blank of the inner liner body (300) embedded with the first pre-fired wear-resistant plate (400) to 300°C - 500°C to ablate the organic glue. 7) Introduce high-purity nitrogen and heat to 1410 - 1450°C to obtain the inner liner body (300) embedded with the first pre-fired wear-resistant plate (400); or introduce air and heat to 1410 - 1450°C to obtain the inner liner body (300) embedded with the first pre-fired wear-resistant plate (400). 8) Place the inner liner body (300) embedded with the first pre-fired wear-resistant plate (400) into the outer shell (100) for positioning, and inject the mixture forming the buffer layer (200) between the two; after the mixture hardens to form the buffer layer (200), combine the inner liner body (300), the outer shell (100), and the first pre-fired wear-resistant plate (400) into an integral whole.

Images