Wear-resistant ceramic composite metal slurry pump for mineral processing, and forming process

Abstract

A wear-resistant ceramic composite metal slurry pump for mineral processing. The slurry pump comprises a bracket (1), a bearing assembly (2), a stuffing box (3), a pump casing (4), and wetted parts; the wetted parts include a front liner (5), a rear liner (6), a throat bushing (7), and an impeller (8); the front liner (5), the rear liner (6), the throat bushing (7), and the impeller (8) each adopt a composite structure in which ceramic blocks are bonded to metal, and the ceramic blocks are bonded to a metal framework in wear-prone areas of the wetted parts by means of an adhesive.

Description

A wear-resistant ceramic composite metal slurry pump for mineral processing and its forming process Technical Field

[0001] The invention belongs to the technical field of centrifugal slurry pumps and wear-resistant ceramics for mineral processing, and relates to a wear-resistant ceramic composite metal slurry pump for mineral processing and a molding process. Background Art

[0002] The flow parts of the existing all-ceramic slurry pumps in the prior art mainly use silicon nitride combined with silicon carbide ceramic materials and silicon carbide materials. Silicon nitride combined with silicon carbide ceramic materials have simple preparation processes, low investment costs, high impact resistance, and are suitable for large-scale and large-scale production. However, when conveying ore processing containing large particles of 4-18mm and high-concentration slurry, due to the high porosity and volume density of 2.65g / cm 3 The density is low, resulting in relatively poor wear resistance.

[0003] Silicon carbide ceramics offer excellent properties such as high temperature resistance, high strength, corrosion resistance, and wear resistance. They are superior to silicon nitride-bonded silicon carbide ceramics in terms of porosity, density, and wear resistance. However, when pure silicon carbide ceramics are used in the lining of large slurry pump flow components, the sintering difficulty and cost increase exponentially with the increase in the size of the flow components, and dimensional accuracy control is difficult. Furthermore, the assembly and sealing of all-ceramic guard plates and sheaths is difficult to ensure, and bonding and fixing ceramic blocks to metal is difficult, which can easily lead to structural damage to the ceramic blocks. Impact resistance is poor, especially when used in impellers, where blades can be easily crushed by slurry particles or steel balls, shortening their service life.

[0004] Compared with the guard plate, sleeve, impeller and other flow-through parts of the all-ceramic pump, the volume of the all-ceramic pump cannot be made too large. Although it is easy to form, it has poor wear resistance and is easy to break.

[0005] Summary of the Invention

[0006] In order to solve the shortcomings of the existing technology, the purpose of the present invention is to provide a wear-resistant ceramic composite metal slurry pump and molding process for mineral processing, aiming to solve the problems that the full silicon carbide material flow-through parts of the slurry pump are difficult to enlarge and easy to break, as well as the problem of bonding between the ceramic material and the metal shell. By firmly bonding the wear-resistant ceramic to the metal skeleton of the flow-through parts, the flow-through parts in the slurry pump are made wear-resistant, corrosion-resistant, have a long service life and low cost.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] The present invention provides a wear-resistant ceramic composite metal slurry pump for mineral processing, the slurry pump comprising: a bracket, a bearing assembly, a stuffing box, a pump casing and a flow-through part; the flow-through part comprises a front guard plate, a rear guard plate, a sleeve and an impeller, the front guard plate, the rear guard plate, the sleeve and the impeller all adopt a composite structure in which ceramic blocks are bonded to a metal skeleton, thereby improving the wear resistance and corrosion resistance of the wear-prone area of ​​the flow-through part; the ceramic blocks are directly bonded to the metal skeleton of the wear-prone area of ​​the flow-through part with an adhesive; the wear-prone area refers to an area near the flow-through part where the fluid linear velocity is greater than 20m / s and / or backflow occurs.

[0009] The bracket is the basic supporting structure of the slurry pump, which is used to fix and carry the bearing assembly, pump shaft and other important components, and ensure the stability and balance of the slurry pump during operation;

[0010] The bearing assembly is mounted on the bracket and includes an axial bearing and a radial bearing, which are used to support and guide the rotation of the pump shaft and bear the axial force and radial force transmitted by the impeller;

[0011] The stuffing box is located at one end or both ends of the pump shaft and has a built-in stuffing seal and / or other forms of shaft sealing devices, which are used to prevent the slurry in the slurry pump from leaking outward along the axial direction, thereby maintaining the working efficiency of the slurry pump and preventing environmental pollution;

[0012] The pump casing is the main structure of the slurry pump, usually composed of upper and lower halves, or front and rear halves, connected by bolts. Components including flow-through parts and / or other wear-resistant bushings are installed inside the pump casing, which is connected to the bracket to form a complete slurry conveying channel.

[0013] In the overflow parts,

[0014] The front guard plate is installed in front of the impeller and cooperates with the inner wall of the pump casing and the sleeve to form a transition flow channel before the slurry enters the impeller, thereby reducing the direct impact and wear of the slurry on the impeller inlet;

[0015] The rear guard plate is installed behind the impeller and cooperates with the inner wall of the pump casing and the sleeve to form a transition channel for the slurry to flow from the impeller to the outlet section of the pump casing, so that the slurry flowing out of the impeller smoothly transitions to the outlet section of the pump casing, playing a role in anti-wear and shock absorption;

[0016] The sheath is tightly attached to the inner wall of the pump casing, forming a spiral flow channel for the slurry to flow through, converting the energy generated by the impeller into the static pressure energy of the slurry. The sheath itself has high wear resistance and protects the pump casing from wear;

[0017] The impeller is mounted on the pump shaft and is driven to rotate by the motor to pressurize and transport the slurry. The impeller, the front guard plate, the rear guard plate and the jacket form a continuous slurry flow channel.

[0018] The various components of the slurry pump are nested and interconnected, forming an efficient and wear-resistant slurry delivery system. The pump shaft runs through the entire pump body, transmitting the motor's power through the bearing assembly to the impeller. The impeller operates within the flow channel formed by the jacket, while the guard plate protects and guides the slurry flow, ensuring that the slurry pump maintains good performance and a long service life under long-term, high-intensity operating conditions.

[0019] The present invention utilizes computational fluid dynamics and discrete element software Rocky coupling calculation method to simulate and calculate the worn area of ​​the flow-through parts, and determines the degree of wear by analyzing the wear amount of the flow-through parts and the distribution area and size of the volume fraction of solid particles in the slurry.

[0020] The adhesive is selected from one or more of epoxy resin structural adhesive, AB adhesive, etc.; the bonding strength of the adhesive is not less than 10MPa;

[0021] The ceramic block is made of wear-resistant ceramic material, including one or more of reaction-sintered silicon carbide ceramic, pressureless-sintered silicon carbide, silicon nitride ceramic or recrystallized ceramic; the density of the ceramic block is not less than 3.03 g / cm 3 , hardness not less than 90HRA; flexural strength not less than 350MPa;

[0022] The radial height of the ceramic block does not exceed 300 mm, the outer diameter width does not exceed 300 mm; the thickness ranges from 15 to 30 mm;

[0023] The gaps between the ceramic blocks are filled with adhesive at high pressure to ensure the integrity of the wear surface of the ceramic blocks and prevent the slurry from wearing through the skeleton through the gaps;

[0024] The metal skeleton is made of materials including high chromium alloy, Q235B carbon structural steel or QT500-7 ductile iron.

[0025] In the slurry pump, the front guard plate and the rear guard plate are respectively installed in front and behind the impeller;

[0026] The front guard plate and / or the rear guard plate both include a guard plate ceramic block and a guard plate metal frame, and the guard plate ceramic block is fixed to the guard plate metal frame by adhesive; the guard plate metal frame includes an integrated hollow metal cylinder and a flat metal ring fixed to one end of the hollow metal cylinder, the inner ring size of the flat metal ring matches the inner diameter of the hollow metal cylinder, the interior of the hollow metal cylinder corresponds to the flow channel inlet area of ​​the slurry pump, and the lower surface of the flat metal ring corresponds to the guard plate plane area; the guard plate ceramic block is attached to the flow channel inlet area and / or the guard plate plane area, that is, the guard plate ceramic block completely fits and covers the inner surface of the hollow metal cylinder and / or the lower surface of the flat metal ring;

[0027] The protective plate ceramic block covering the inner surface of the hollow metal cylinder is an integrated cylindrical ceramic block; and / or,

[0028] The guard plate ceramic blocks covering the lower surface of the planar metal ring are one or more layers, each layer including a ceramic block group consisting of one or more circles of ceramic blocks; the ceramic block group is divided into M circles according to the radial width of the ring on the lower surface of the guard plate; the ceramic block groups of each two adjacent circles are staggered and interlocked by setting a step-like structure; each circle of the ceramic block group is divided into N ceramic blocks in the circumferential direction, and the number of ceramic blocks in the inner and outer circles can be the same or different; the ceramic blocks in the inner and outer circles are mutually nested and fitted in the circumferential direction and the radial direction, and the adjacent two ceramic blocks in each circle are staggered and interlocked by setting a step-like structure; wherein,

[0029] Wherein, D2 is the outer diameter of the guard plate; D1 is the inner diameter of the guard plate; i - the outer diameter circumference of the i-th circle; L1- the radial height of the ceramic block; L2- the outer diameter width of the ceramic block;

[0030] In a specific embodiment, the protective plate ceramic blocks covering the lower surface of the metal ring are 1-2 layers in the axial direction; preventing the slurry from grinding through the metal skeleton from the joints, thereby affecting the service life;

[0031] The joints between the inner ring guard plate ceramic blocks and the outer ring guard plate ceramic blocks of the ceramic block group are staggered;

[0032] The guard plate ceramic blocks are mutually nested and fitted in the circumferential and radial directions;

[0033] The sharp corners of the ceramic blocks of the inner ring guard plate are matched with the impeller inlet, and the matching clearance is controlled at 1-5mm to prevent the slurry from flowing back to the inlet;

[0034] The metal plane of the guard plate and the outermost side of the ceramic block bonded and fixed on the metal plane are wrapped with a sealing ring, that is, the outer side of the entire guard plate is wrapped with a sealing ring, which can ensure a certain sealing performance when assembled with the sleeve.

[0035] The sheath is a detachable structure with front and rear halves or is directly made into an integrated structure, including a sheath ceramic block and a sheath metal shell. The sheath ceramic block is fixed inside the sheath metal shell by an adhesive; specifically, the sheath ceramic block is divided into N pieces along the circumferential direction of the sheath metal shell, covering the entire internal flow surface of the metal sheath or the local wear-prone area, such as the tongue area, and the sheath ceramic block is fixed to the sheath metal shell by an adhesive.

[0036] The impeller includes an impeller ceramic block and an impeller metal frame;

[0037] The impeller ceramic block is fixed to the wear-prone area of ​​the impeller by adhesive; the wear-prone area of ​​the impeller includes the impeller suction port, the outer diameter circumference of the front cover plate, the outer diameter circumference of the rear cover plate, and the blade working surface; the corresponding impeller ceramic blocks include the impeller suction port ceramic block, the front cover plate outer diameter circumference ceramic block, the rear cover plate outer diameter circumference ceramic block, and the blade working surface ceramic block;

[0038] The impeller metal frame is made of high chromium alloy material.

[0039] In the present invention, different ceramic blocks may have different compositions according to actual needs, or may have the same composition.

[0040] In a specific embodiment, the impeller includes a front cover plate, a rear cover plate and a plurality of blades, the front cover plate and the rear cover plate are arranged opposite to each other, the plurality of blades are arranged between the front cover plate and the rear cover plate, and the front cover plate and the rear cover plate are connected through the plurality of blades; in the impeller, each blade is in the shape of a circular arc.

[0041] In the specific implementation process, the ceramic blocks that need to be bonded to the guard plate, sleeve, and impeller can be provided with grooves of appropriate size and depth on the metal frame, and the ceramic blocks can be bonded and fixed in the grooves to enhance the connection strength between the ceramic blocks and the metal frame through the grooves.

[0042] In a specific implementation process, a plurality of the grooves are provided on the inner side surface of the front cover plate facing the rear cover plate, and are spaced apart along the circumferential direction of the inner side surface of the front cover plate; and / or,

[0043] The plurality of grooves are provided on the inner side surface of the rear cover plate facing the front cover plate, and are spaced apart along the circumferential direction of the inner side surface of the rear cover plate; and / or,

[0044] A plurality of grooves are provided on the inner surface of the impeller suction port; and / or,

[0045] A plurality of grooves are provided on the working surface of each blade.

[0046] Each of the wear-resistant ceramic blocks is fixedly connected to the impeller via an adhesive.

[0047] The present invention also provides a method for preparing a composite material of a ceramic block bonded to a metal. The preparation method includes: applying an adhesive on the surface of the ceramic block, placing it on the bonding position of the metal skeleton, placing the metal skeleton bonded with the ceramic block into an oven for curing, setting the temperature to 80-100°C and the drying time to 1-2 hours, thereby improving the surface bonding strength between the ceramic and the metal.

[0048] In the present invention, when the ceramic blocks are severely worn locally, they can be replaced individually, thereby extending the service life and reducing maintenance costs.

[0049] The beneficial effects of the present invention are: by utilizing CFD and ROCKY coupling calculation methods to simulate the wear areas of the flow-through parts such as the front guard plate, rear guard plate, sleeve and impeller, the idea of ​​bonding block ceramics on the corresponding metal skeleton wear surface is adopted, the wear resistance and corrosion resistance of silicon carbide ceramic materials are fully utilized, and the overall service life of the slurry pump is improved. The solution of bonding ceramics in blocks according to the wear areas solves the problems of silicon carbide ceramics being difficult to scale up and being brittle. The bonding molding process solves the problem of bonding ceramic blocks to metals. The ceramic blocks can be replaced individually and the maintenance cost is low, further improving production efficiency.

[0050] The ceramic composite metal slurry pump provided by the present invention takes advantage of the wear resistance and corrosion resistance of ceramics. The block design solves the problem that silicon carbide ceramics are difficult to scale up and are brittle. The ceramic blocks can be replaced individually and the maintenance cost is low. It is particularly suitable for conveying media containing solid particles and corrosive media in mineral processing, metallurgy, chemical industry, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0052] FIG1 is a schematic structural diagram of a wear-resistant ceramic composite metal slurry pump for mineral processing according to the present invention.

[0053] FIG2 is a schematic structural diagram of a ceramic composite metal front guard plate of the present invention.

[0054] FIG3 is a cross-sectional view of a front guard plate structure of a ceramic composite metal according to the present invention.

[0055] FIG4 is a schematic diagram of a ceramic composite metal sheath structure of the present invention.

[0056] FIG5 is a cross-sectional view of a ceramic composite metal sheath structure of the present invention.

[0057] FIG6 is a schematic diagram of the structure of a ceramic composite metal impeller of the present invention.

[0058] FIG7 is a cross-sectional view of a ceramic composite metal impeller structure of the present invention.

[0059] In the figure, 1. bracket; 2. bearing assembly; 3. stuffing box; 4. pump casing; 5. front guard plate; 6. rear guard plate; 7. sleeve; 8. impeller; 9. guard plate ceramic block; 9a. cylindrical ceramic block; 9b. inner ring guard plate ceramic block; 9c. outer ring guard plate ceramic block; 11. guard plate metal frame; 12. sleeve ceramic block; 13. sleeve metal shell; 14. impeller ceramic block; 14a. impeller suction port ceramic block; 14b. front cover plate outer diameter circumference ceramic block; 14c. rear cover plate outer diameter circumference; 14d. blade working surface ceramic block; 15. impeller metal frame. DETAILED DESCRIPTION

[0060] The present invention will be further described in detail with reference to the following specific examples and accompanying drawings. The processes, conditions, experimental methods, etc. for implementing the present invention, except for those specifically mentioned below, are common knowledge and common common sense in the art and are not particularly limited by the present invention.

[0061] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0062] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0063] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0064] In this application, the term "comprising" is an open expression, that is, including the contents specified in the present invention, but not excluding other aspects.

[0065] In this application, the term "about" when applied to a value means allowing some slight imprecision in the value in the calculation or measurement (approximately or reasonably close to the value by some means).

[0066] In this application, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0067] The disclosure below provides many different embodiments or examples for realizing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0068] The present invention provides a wear-resistant ceramic composite metal slurry pump for mineral processing, which includes: a bracket 1, a bearing assembly 2, a stuffing box 3, a pump casing 4, a front guard plate 5, a rear guard plate 6, a sleeve 7, and an impeller 8. The front guard plate 5, the rear guard plate 6, the sleeve 7, the impeller 8 and other flow-through parts all adopt a composite structure in which ceramic blocks are bonded to a metal frame.

[0069] Furthermore, the CFD and Rocky coupling calculation method is used to simulate the wear-prone areas of the flow-through parts such as the front guard plate 5, the rear guard plate 6, the jacket 7 and the impeller 8, and ceramic blocks are bonded to the corresponding wear areas;

[0070] Furthermore, the front guard plate 5 and the rear guard plate 6 each include a guard plate ceramic block 9 and a guard plate metal frame 11; the guard plate ceramic block 9 is fixed to the guard plate metal frame 11 with an adhesive; the guard plate ceramic block 9 is divided into two areas, an entrance and a plane area, and a cylindrical ceramic block 9a is bonded to the guard plate entrance; the ceramic blocks in the plane area are divided into M circles according to the diameter of the guard plate, and the inner circle guard plate ceramic block 9b and the outer circle guard plate ceramic block 9c are evenly divided into N pieces along the circumferential direction. The circumferential direction and the radial direction are nested and fitted with each other to prevent the slurry from wearing through the guard plate metal frame 11 from the joints, thereby affecting the service life;

[0071] The seams of the inner ring guard plate ceramic block 9b and the seams of the outer ring guard plate ceramic block 9c should be staggered;

[0072] The sharp corners of the inner ring guard plate ceramic block 9b cooperate with the inlet of the impeller 8 to prevent the slurry from flowing back to the inlet;

[0073] The outer diameter of the guard plate 8 is wrapped with a sealing ring, which ensures a certain degree of sealing when assembled with the sheath 7.

[0074] Furthermore, the sheath 7 is an integral structure, comprising a sheath ceramic block 12 and a sheath metal shell 13; the sheath ceramic block 12 is divided into N pieces along the circumferential direction of the sheath metal shell 13; based on the calculated easily worn area of ​​the sheath, the sheath ceramic block 12 is fixed to the sheath metal shell 13 by an adhesive, covering the entire metal sheath flow surface or a local location with severe wear, such as the tongue area;

[0075] Furthermore, the impeller 8 comprises an impeller ceramic block 14 and an impeller metal frame 15;

[0076] The impeller ceramic block 14 is bonded to the impeller 8's easily worn areas based on the calculated easily worn areas of the impeller 8, including the impeller suction port, the outer diameter circumference of the front cover plate, the outer diameter circumference of the rear cover plate, and the blade working surface. The impeller ceramic block 14 is bonded to the main surface of the impeller 8 with an adhesive and then cured at high temperature.

[0077] The impeller metal frame 15 is made of high chromium alloy material;

[0078] Furthermore, the adhesive may be one or more of epoxy resin structural adhesive, AB adhesive, etc.; the gaps between the ceramic blocks are filled with the adhesive under high pressure to ensure the integrity of the wear surface of the ceramic blocks and prevent the slurry from grinding through the skeleton through the gaps;

[0079] Furthermore, the ceramic blocks are made of wear-resistant ceramic materials, including the guard plate ceramic block 9, the sheath ceramic block 12 and the impeller ceramic block 14, which can be made of any one of reaction-sintered silicon carbide ceramics, pressureless-sintered silicon carbide, silicon nitride ceramics or recrystallized ceramics, either alone or in combination to form a wear-resistant ceramic layer; the density of the ceramic blocks is not less than 3.03 g / cm 3 , hardness not less than 90HRA; flexural strength not less than 350MPa;

[0080] Furthermore, when the ceramic blocks are severely worn locally, they can be replaced individually, thus extending their service life and reducing maintenance costs.

[0081] Furthermore, the material of the metal skeleton can be high chromium alloy, Q235B carbon structural steel or QT500-7 ductile iron and other grades of materials.

[0082] Example 1

[0083] As shown in FIG1 , the wear-resistant ceramic composite metal slurry pump for mineral processing in this embodiment includes a bracket 1, a bearing assembly 2, a stuffing box 3, a pump casing 4, a front guard plate 5, a rear guard plate 6, a sleeve 7, and an impeller 8;

[0084] As shown in FIG2 , the front guard plate 5 includes a guard plate ceramic block 9 and a guard plate metal frame 11.

[0085] The shield's ceramic blocks 9 are divided into two areas: the inlet and the flat surface. A cylindrical ceramic block 9a is bonded to the front shield's inlet. The flat surface area is divided into two rings, with the inner and outer rings evenly spaced circumferentially. These blocks comprise eight inner shield blocks 9b and 12 outer shield blocks 9c, nested and fitted together circumferentially and radially, as shown in Figure 3. This prevents slurry from wearing through the metal frame at the joints, which could affect its lifespan. The joints between the inner and outer shield blocks 9b and 9c are staggered. The sharp corners of the inner shield blocks mate with the impeller inlet to prevent slurry from flowing back into the inlet. A sealing ring 9d is wrapped around the outer diameter of the shield to ensure a tight seal when assembled with the sleeve. The shield's metal frame 11 is made of Q235B carbon structural steel. The metal bonding method for the rear shield 6 is the same as for the front shield 5.

[0086] As shown in Figures 4 and 5, the sheath 7 is an integral structure, including a sheath ceramic block 12 and a sheath metal shell 13; the sheath ceramic block 12 is divided into 17 parts along the circumferential direction of the sheath metal shell 13; the wear position is obtained by using CFD and Rocky coupling calculation methods, the sheath ceramic block 12 covers the entire metal sheath flow surface, and the sheath ceramic block 12 is fixed to the sheath metal shell 13 by adhesive; wherein, the sheath metal shell 13 is made of QT500-7 ductile iron material.

[0087] As shown in Figures 6 and 7, the impeller 8 includes an impeller ceramic block 14 and an impeller metal frame 15. The impeller ceramic block 14 is bonded to the impeller's wear-prone areas, including the impeller suction port, the front cover circumference, the rear cover circumference, and the blade working surface, based on the wear areas calculated by CFD and Rocky coupling. The impeller ceramic block 14 is bonded to the surface of the impeller 8 body with adhesive and then cured at high temperature. The impeller metal frame 15 is made of high-chromium alloy.

[0088] In this embodiment, the guard plate ceramic block 9, the jacket ceramic block 12 and the impeller ceramic block 14 are made of reaction-sintered silicon carbide material.

[0089] The adhesive can be epoxy resin structural adhesive, AB adhesive or a combination of resin and silicon carbide; the gaps between the ceramic blocks are filled with adhesive under high pressure to ensure the integrity of the wear surface of the ceramic blocks and prevent the slurry from grinding through the skeleton through the gaps;

[0090] Combined with the above steps, the front guard plate 5, rear guard plate 6, sleeve 7, impeller 8, pump casing 4, bearing assembly 2, stuffing box 3 and bracket 1 with ceramic bonding metal are finally assembled to form a complete slurry pump.

[0091] Example 2

[0092] The wear-resistant ceramic composite metal slurry pump for mineral processing in this embodiment includes a bracket 1, a bearing assembly 2, a stuffing box 3, a pump casing 4, a front guard plate 5, a rear guard plate 6, a sleeve 7, and an impeller 8;

[0093] The front guard plate 5 includes a guard plate ceramic block 9 and a guard plate metal frame 11.

[0094] The shield's ceramic blocks 9 are divided into two areas: the inlet and the flat surface. A cylindrical ceramic block 9a is bonded to the front shield's inlet. The flat surface area is divided into three rings, with the inner and outer rings evenly spaced circumferentially. These blocks comprise seven inner ring blocks 9b and ten outer ring blocks 9c, nesting and fitting together circumferentially and radially to prevent slurry from wearing through the metal frame at the joints, which could affect its lifespan. The joints between the inner and outer ring blocks 9b and 9c are staggered. The sharp corners of the inner ring blocks mate with the impeller inlet to prevent slurry from backflowing into the inlet. A sealing ring 9d is wrapped around the outer diameter of the shield to ensure a tight seal when assembled with the sleeve. The shield's metal frame 11 is made of Q235B carbon structural steel. The metal bonding method for the rear shield 6 is the same as for the front shield 5.

[0095] The sheath 7 is an integral structure, comprising a sheath ceramic block 12 and a sheath metal shell 13; the sheath ceramic block 12 is divided into 15 parts along the circumferential direction of the sheath metal shell 13; the sheath flow surface is covered with local areas of severe wear, and the severe wear areas of the tongue area are separated by CFD and Rocky coupling calculation methods, and the sheath ceramic block 12 is fixed to the sheath metal shell 13 by adhesive; wherein, the sheath metal shell 13 is made of QT500-7 ductile iron material.

[0096] The impeller 8 comprises an impeller ceramic block 14 and an impeller metal frame 15. The impeller ceramic block 14 is bonded to the impeller's wear-prone areas, including the impeller suction port, the front cover circumference, the rear cover circumference, and the blade working surface, based on the wear areas calculated by CFD and Rocky coupling. The impeller ceramic block 14 is bonded to the main surface of the impeller 8 with an adhesive and then cured at high temperature. The impeller metal frame 15 is made of high-chromium alloy material.

[0097] In this embodiment, the guard plate ceramic block 9, the jacket ceramic block 12 and the impeller ceramic block 14 are made of pressureless sintered silicon carbide material.

[0098] The adhesive can be AB glue; the gaps between the ceramic blocks are filled with the adhesive under high pressure to ensure the integrity of the wear surface of the ceramic blocks and prevent the slurry from grinding through the skeleton from the gaps;

[0099] Combined with the above steps, the front guard plate 5, rear guard plate 6, sleeve 7, impeller 8, pump casing 4, bearing assembly 2, stuffing box 3 and bracket 1 with ceramic bonding metal are finally assembled to form a complete slurry pump.

[0100] Example 3

[0101] This embodiment provides a method for preparing a composite material of ceramic blocks bonded to metal, the preparation method comprising: applying an adhesive to the surface of the ceramic block, placing the adhesive on the bonding position of the metal skeleton, placing the metal skeleton bonded with the ceramic block into an oven for curing, setting the temperature to 80°C and the drying time to 2 hours.

[0102] Example 4

[0103] This embodiment provides a slurry pump, wherein the impeller includes an impeller body and a plurality of wear-resistant ceramic blocks bonded thereto, wherein the material of the impeller is cemented carbide.

[0104] Among them, the impeller is made of cemented carbide, which can improve the stability of the mechanical properties of the slurry pump impeller.

[0105] The number of wear-resistant ceramic blocks can be set according to actual conditions and is not specifically limited here.

[0106] The impeller comprises a front cover plate, a rear cover plate and a plurality of blades. The front cover plate and the rear cover plate are arranged opposite to each other. The plurality of blades are arranged between the front cover plate and the rear cover plate. The front cover plate and the rear cover plate are connected through the plurality of blades.

[0107] A plurality of grooves are provided in the wear-prone area of ​​the impeller, and the wear-resistant ceramic blocks are arranged in the grooves and fixedly connected to the impeller.

[0108] In a specific embodiment, multiple grooves can be set in the wear-prone area of ​​the impeller, and a wear-resistant ceramic block can be set in each groove. The high hardness, wear resistance and corrosion resistance of the wear-resistant ceramic can be utilized to improve the local wear resistance of the slurry pump impeller, thereby increasing the life of the slurry pump impeller and solving the problem of short life of the slurry pump impeller.

[0109] The use of multiple small wear-resistant ceramic blocks placed in the wear-prone areas of the impeller can solve the process difficulty of large-scale wear-resistant ceramics and reduce the cost of the slurry pump impeller. The size of the wear-resistant ceramic blocks can be determined according to the diameter of the impeller and the ceramic molding process.

[0110] An impeller suction port is provided in the middle of the impeller front cover plate, wherein the fluid enters the slurry pump impeller through the impeller suction port.

[0111] The plurality of grooves are arranged on the inner side surface of the front cover plate facing the rear cover plate and are spaced apart along the circumferential direction of the inner side surface of the front cover plate. That is, the inner side surface of the front cover plate facing the rear cover plate is a position prone to wear of the impeller.

[0112] The plurality of grooves are arranged on the inner side of the rear cover plate facing the front cover plate and are spaced apart along the circumferential direction of the inner side of the rear cover plate. That is, the inner side of the rear cover plate facing the front cover plate is a position prone to wear of the impeller.

[0113] The plurality of grooves are arranged on the inner surface of the impeller suction port, that is, the inner surface of the impeller suction port is a position prone to wear of the impeller.

[0114] The working surface of each blade is provided with a plurality of grooves, that is, the working surface of each blade is a part of the impeller that is prone to wear.

[0115] Each wear-resistant ceramic block is fixedly connected to the impeller through an adhesive.

[0116] The plurality of wear-resistant ceramic blocks include at least one of silicon carbide ceramics, silicon nitride-bonded silicon carbide ceramics, silicon oxide ceramics-bonded silicon carbide ceramics and recrystallized ceramics.

[0117] For example, multiple wear-resistant ceramic blocks are all silicon carbide ceramics, or a portion of the multiple wear-resistant ceramic inserts are silicon carbide ceramics, and the remaining portions are silicon nitride-bonded silicon carbide ceramics. In other words, the wear-resistant ceramic blocks can be composed of any one of silicon carbide ceramics, silicon nitride-bonded silicon carbide ceramics, silicon oxide ceramics-bonded silicon carbide ceramics, and recrystallized ceramics, either alone or in combination.

[0118] Among them, the impeller is cast in one piece.

[0119] A raised portion is provided in the middle of the rear cover plate, and a threaded hole for matching and connecting with the pump shaft of the slurry pump is provided at the center of the raised portion.

[0120] Wherein, each blade is in the shape of an arc.

[0121] The slurry pump impeller provided in the present invention improves the local wear resistance of the slurry pump impeller by providing multiple grooves in the wear-prone areas of the impeller, with a wear-resistant ceramic block placed in each groove. The high hardness, wear resistance, and corrosion resistance of the wear-resistant ceramic are utilized to improve the local wear resistance of the slurry pump impeller, thereby increasing the lifespan of the slurry pump impeller and resolving the problem of short lifespan of the slurry pump impeller. Furthermore, because the impeller is made of cemented carbide, the mechanical properties of the slurry pump impeller are stable. Finally, the use of multiple small wear-resistant ceramic blocks in the wear-prone areas of the impeller can solve the process difficulties of large-scale wear-resistant ceramics and reduce the cost of the slurry pump impeller.

[0122] The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the present invention, changes and advantages that can be thought of by those skilled in the art are included in the present invention and are protected by the appended claims.

Claims

1. A wear-resistant ceramic composite metal slurry pump for mineral processing, characterized in that: The slurry pump comprises: a bracket (1), a bearing assembly (2), a stuffing box (3), a pump casing (4) and a flow-through part; wherein the flow-through part comprises a front guard plate (5), a rear guard plate (6), a sleeve (7) and an impeller (8); the front guard plate (5), the rear guard plate (6), the sleeve (7) and the impeller (8) all adopt a composite structure in which a ceramic block is bonded to a metal frame; the ceramic block is bonded to the metal frame of the wear-prone area of ​​the flow-through part with an adhesive; the wear-prone area refers to an area near the flow-through part where the fluid linear velocity is greater than 20 m / s and / or backflow occurs.

2. The slurry pump according to claim 1, characterized in that: The wear-prone area is obtained by simulation calculation using computational fluid dynamics and discrete element software Rocky coupling calculation method, and the degree of wear is determined by analyzing the wear amount of the flow-through parts and the distribution area and size of the volume fraction of solid particles in the slurry.

3. The slurry pump according to claim 1, characterized in that: The adhesive is selected from epoxy resin structural adhesive and / or AB adhesive; the bonding strength of the adhesive is not less than 10MPa; The ceramic block is made of wear-resistant ceramic material, including one or more of reaction-sintered silicon carbide ceramic, pressureless-sintered silicon carbide, silicon nitride ceramic or recrystallized ceramic; the density of the ceramic block is not less than 3.03 g / cm 3 , hardness not less than 90HRA; flexural strength not less than 350MPa; The radial height of the ceramic block does not exceed 300 mm, the outer diameter width does not exceed 300 mm; the thickness ranges from 15 to 30 mm; The gaps between the ceramic blocks are filled with adhesive; The metal skeleton is made of high chromium alloy, Q235B carbon structural steel or QT500-7 ductile iron.

4. The slurry pump according to claim 1, characterized in that: The front guard plate (5) and / or the rear guard plate (6) both include: a guard plate ceramic block (9) and a guard plate metal frame (11); the guard plate ceramic block (9) is fixed to the guard plate metal frame (11) by adhesive; the guard plate metal frame (11) includes an integrated hollow metal cylinder and a flat metal ring fixed to one end of the hollow metal cylinder, and the inner ring size of the flat metal ring matches the inner diameter of the hollow metal cylinder; the guard plate ceramic block (9) completely fits and covers the inner surface of the hollow metal cylinder and / or the lower surface of the flat metal ring.

5. The slurry pump according to claim 4, characterized in that: The portion of the guard plate ceramic block (9) covering the inner surface of the hollow metal cylinder is an integrated cylindrical ceramic block (9a); and / or, The portion of the guard plate ceramic block (9) covering the lower surface of the planar metal ring is one or more layers, each layer comprising a ceramic block group consisting of one or more circles of ceramic blocks; the ceramic block group is divided into M circles according to the radial width of the circle on the lower surface of the guard plate; the ceramic block groups of each two adjacent circles are staggered and interlocked by setting a step-like structure; each circle of the ceramic block group is equally divided into N ceramic blocks along the circumferential direction, and the adjacent ceramic blocks in each circle are staggered and interlocked by setting a step-like structure; wherein, Among them, D2 is the outer diameter of the guard plate; D1 is the inner diameter of the guard plate; D i is the outer diameter circumference of the i-th circle; L1 is the radial height of the ceramic block; L2 is the outer diameter width of the ceramic block; The joints between the inner ring guard plate ceramic blocks (9b) and the outer ring guard plate ceramic blocks (9c) of the ceramic block group are staggered; The sharp corner of the inner ring guard plate ceramic block (9b) is matched with the impeller inlet, and the matching clearance is controlled within 1-5 mm.

6. The slurry pump according to claim 5, characterized in that: The outer side of the guard plate is wrapped with a sealing ring (9d).

7. The slurry pump according to claim 1, characterized in that: The sheath (7) comprises: a sheath ceramic block (12) and a sheath metal shell (13); the sheath ceramic block (12) is fixed inside the sheath metal shell (13) by means of an adhesive; the sheath ceramic block (12) is divided into N pieces along the circumferential direction of the sheath metal shell (13), covering the entire internal flow surface or easily-worn area of ​​the sheath.

8. The slurry pump according to claim 1, wherein: The impeller (8) comprises: an impeller ceramic block (14) and an impeller metal frame (15); The impeller ceramic block (14) is fixed to the easily worn area of ​​the impeller (8) by means of an adhesive; the easily worn area of ​​the impeller (8) includes the impeller suction port, the outer diameter circumference of the front cover plate, the outer diameter circumference of the rear cover plate, and the blade working surface; the corresponding impeller ceramic block (14) includes the impeller suction port ceramic block (14a), the front cover plate outer diameter circumference ceramic block (14b), the rear cover plate outer diameter circumference ceramic block (14c), and the blade working surface ceramic block (14d); The impeller metal skeleton (15) is made of high chromium alloy.

9. A method for preparing a composite material of ceramic blocks bonded to metals, characterized in that: The preparation method comprises: applying an adhesive on the surface of a ceramic block, placing the adhesive on the bonding position of a metal skeleton, placing the metal skeleton bonded with the ceramic block in an oven for curing, setting the temperature to 80-100° C. and drying for 1-2 hours.

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