A method and apparatus for manufacturing a catalytic slurry pump body liner

Abstract

The application discloses a manufacturing method and device of a catalytic oil slurry pump body liner, and relates to the technical field of catalytic oil slurry pump manufacturing. The method comprises the following steps: pressure casting anti-wear white cast iron melt into an oil slurry pump body liner shell made of nano-alumina, and obtaining the pump body liner with a layer of corundum ceramic layer on the surface after cooling; the corundum ceramic layer is metallurgically combined with the anti-wear white cast iron. The method comprises the following steps: firstly, using nano-alumina to make a pump body liner shell; fixing a casting system formed by the pump body liner shell in the manufacturing device of the technical solution; and then, pressure casting anti-wear white cast iron into the pump body liner shell. The formed pump body liner has a dense corundum ceramic layer formed by nano-alumina on the surface, so that the pump body liner can be resistant to high temperature, high pressure, corrosion and abrasion, and has a long service life.

Description

Technical Field

[0001] This invention relates to the field of catalytic oil slurry pump manufacturing technology, specifically to a method and apparatus for manufacturing a catalytic oil slurry pump body lining. Background Technology

[0002] Catalytic slurry pumps are centrifugal pumps used in chemical processes to pump slurries. Due to the high content of metallic catalysts in the slurry and the harsh operating conditions of high temperature, high pressure, and corrosion, the pump body lining of these centrifugal pumps is typically made of wear-resistant white cast iron. However, during use, erosion damage and cracking are still prone to occur, resulting in a short service life, far exceeding the 20-year lifespan required by API 610. Furthermore, wear-resistant white cast iron has poor weldability; when erosion damage and cracking occur, the welding repair process is prone to stress concentration, causing the pump body lining to crack again. Therefore, once erosion and cracking occur in the pump body lining, replacement is the only option, leading to high maintenance costs. To improve the erosion resistance of the pump body lining, a thermal spraying process is used to apply a layer of wear-resistant material to the surface of the pump body lining. However, this process is prone to uneven heating and cracking of the wear-resistant white cast iron during high-temperature thermal spraying, resulting in a low yield rate and high costs. Summary of the Invention

[0003] The purpose of this invention is to provide a method and apparatus for manufacturing a liner for a catalytic oil slurry pump body, so as to solve the problems in the prior art.

[0004] To achieve the above objectives, the present invention creatively proposes the following technical solution: a method for manufacturing a liner for a catalytic oil slurry pump body, wherein molten anti-wear white cast iron is die-cast into an oil slurry pump body liner mold shell made of nano-alumina, and after cooling, a pump body liner with a corundum ceramic layer on the surface is obtained, wherein the corundum ceramic layer and the anti-wear white cast iron are metallurgically bonded.

[0005] Furthermore, the fabrication and casting of the pump body lining shell includes the following steps:

[0006] A. Perform three-dimensional parametric modeling of the pump body lining;

[0007] B. Prepare a wax model. Import the 3D model data obtained in step A into a 3D printer and print it.

[0008] Prepare the wax model;

[0009] C. Prepare a nano-alumina coating: Spray nano-alumina slurry onto the surface of the wax model obtained in step B to a set thickness, and after drying, form a nano-alumina coating on the surface of the wax model.

[0010] D. In step C, the set position of the wax mold sprayed with nano alumina slurry is removed to form a reserved casting connection port and a venting connection port for casting.

[0011] E. Dewaxing and sintering the wax mold coated with nano-alumina slurry obtained in step D to obtain a hollow corundum ceramic structure pump body lining shell.

[0012] F. Take the corundum ceramic structure pump body liner shell obtained in step E, and braze a casting pipe and a venting pipe of the same material as the pump body liner shell to the casting connection port and the venting connection port respectively, to obtain a pump body liner shell with a casting system.

[0013] H. The wear-resistant white cast iron molten liquid is pressure cast from the casting pipe into the pump body lining shell by pressure casting, and the pump body lining billet is obtained after cooling to room temperature.

[0014] I. Remove the casting pipe and vent pipe from the pump body lining billet obtained in step H, and braze the broken ends with titanium wire to make them flush, so as to obtain a pump body lining with a corundum ceramic layer on the surface that is metallurgically bonded to the wear-resistant white cast iron core.

[0015] Furthermore, the thickness of the nano-alumina coating is 0.3–0.5 mm.

[0016] Furthermore, the particle size of the nano-alumina is 3 nanometers.

[0017] Furthermore, in step E, dewaxing is completed during the sintering heating process.

[0018] Furthermore, the welding wire used for brazing in step F is titanium wire.

[0019] Furthermore, the lengths of the casting pipe and the venting pipe are determined as follows:

[0020] Determine the pressure value that matches the casting shrinkage of wear-resistant white cast iron based on the three-dimensional model data obtained in step A;

[0021] Determine the height of the gate opening from the top of the casting based on the pressure value;

[0022] The lengths of the casting pipe and the venting pipe are determined based on the height.

[0023] A manufacturing apparatus for a catalytic oil slurry pump body liner, used to fix the aforementioned casting system consisting of the pump body liner mold shell, the casting pipe, and the venting pipe brazed together, includes at least a sand box for accommodating the brazed pump body liner mold shell, the casting pipe, and the venting pipe; the inner wall of the sand box and the casting system are filled with quartz sand, the sand box is covered with a sand box cover and fasteners are used to connect the sand box cover and the sand box, and the upper openings of the casting pipe and the venting pipe protrude from the surface of the sand box cover.

[0024] The beneficial effects of this invention are as follows: The process involves first creating a corundum blank, followed by die casting. Specifically, a pump body lining shell is first made using nano-alumina as the corundum blank. Then, wear-resistant white cast iron is die-cast into the pump body lining shell. This results in a dense corundum ceramic layer formed by the transformation of nano-alumina onto the surface of the formed pump body lining. This enables the pump body lining to withstand high temperatures, high pressures, corrosion, and wear, resulting in a long service life. When the corundum ceramic layer is eroded, it can be brazed with titanium wire in a vacuum environment at the eroded location, providing good maintainability. Attached Figure Description

[0025] Figure 1 A top view of the pump body liner prepared according to the method of the present invention;

[0026] Figure 2 for Figure 1 MM section view;

[0027] Figure 3 A cross-sectional view of the pump body liner shell manufactured according to the method of the present invention;

[0028] Figure 4 This is a schematic diagram of the manufacturing apparatus for the catalytic slurry pump body liner of the present invention.

[0029] Figure 5 A partially enlarged view of the pump body lining produced by the method of the present invention.

[0030] In the diagram: 1. Casting gate; 2. Casting pipe; 3. Casting connection port; 4. Pump body lining shell; 5. Gas vent connection port; 6. Gas vent pipe; 7. Gas vent; 8. Sand box; 9. Sand box cover; 10. Stud; 11. Nut; 12. Quartz sand; 13. Casting system; 14. Pump body lining; 1401. Corundum ceramic layer; 1402. Wear-resistant white cast iron. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Please see Figure 1-5 A method for manufacturing a catalytic oil slurry pump body lining involves die-casting molten wear-resistant white cast iron into a pump body lining shell made of nano-alumina. After cooling, a pump body lining with a corundum ceramic layer on its surface is obtained, where the corundum ceramic layer and the wear-resistant white cast iron are metallurgically bonded. This technical solution adopts a process of first creating a corundum blank and then die-casting. Specifically, a pump body lining shell is first made using nano-alumina as the corundum blank, and then wear-resistant white cast iron is die-cast into the shell. This results in a dense corundum ceramic layer formed by the transformation of nano-alumina onto the surface of the formed pump body lining, enabling the pump body lining to withstand high temperatures, high pressures, corrosion, and wear, and providing a long service life. When the corundum ceramic layer is eroded, it can be brazed with titanium wire in a vacuum environment, providing good maintainability.

[0033] Specifically, the fabrication and casting of the pump body lining shell includes the following steps:

[0034] A. Perform three-dimensional parametric modeling of the pump body lining;

[0035] B. Prepare a wax model: Import the three-dimensional model data obtained in step A into a 3D printer and print to prepare a wax model.

[0036] C. Preparation of nano-alumina coating: Spray nano-alumina slurry onto the surface of the wax model obtained in step B to a set thickness. After drying, a nano-alumina coating is formed on the surface of the wax model. In a preferred embodiment, the thickness of the nano-alumina coating is 0.3 to 0.5 mm. In a further preferred embodiment, the thickness of the nano-alumina coating is controlled at 0.3 mm. At this time, due to the support of the wax model, the coating has good stability.

[0037] D. In step C, the set position of the wax mold sprayed with nano alumina slurry is removed to form the reserved casting connection port 3 and the venting connection port 5 for casting.

[0038] E. The wax mold coated with nano-alumina slurry obtained in step D is dewaxed and sintered to obtain a hollow corundum ceramic structure pump body lining shell. In a preferred embodiment, in this step, dewaxing is completed during the sintering heating process. Thus, during the sintering operation, as the temperature rises, the wax mold gradually melts and flows out from the casting connection port 3, and is transported out for recycling through the pipes in the sintering furnace. After the temperature rises to the set temperature, the nano-alumina coating is transformed into a corundum ceramic structure. During this process, the position of the pump body lining shell is fixed to avoid deformation of the coating structure, ensuring that the shape and dimensional accuracy of the pump body lining shell 4 after being transformed into a corundum ceramic structure are stable. After cooling, the corundum ceramic structure pump body lining shell 4 is obtained. Here, the atmospheric pressure sintering process is used, which has a high success rate, high strength of the pump body lining shell 4, smooth surface, and is convenient for subsequent pressure casting.

[0039] F. The pump body lining shell with corundum ceramic structure obtained in step E is brazed to casting pipe 2 and venting pipe 6 of the same material as the pump body lining shell at casting connection port 3 and venting connection port 5 respectively, to obtain pump body lining shell 4 with casting system 13.

[0040] H. The wear-resistant white cast iron molten liquid is pressure cast from the casting pipe 2 into the pump body lining shell 4 by pressure casting. After cooling to room temperature, the pump body lining billet is obtained. Here, the preferred grade of wear-resistant white cast iron is BTMCr15.

[0041] I. Remove the casting pipe 2 and the vent pipe 6 from the pump body lining billet obtained in step H, and braze the broken ends with titanium wire to make them flush, so as to obtain a pump body lining 14 with a corundum ceramic layer that is metallurgically bonded to the core of wear-resistant white cast iron 1402. That is, the pump body lining 14 obtained by this method has a core of wear-resistant white cast iron 1402 and a corundum ceramic layer 1401 that is wrapped around it and metallurgically bonded to the wear-resistant white cast iron 1402 material.

[0042] More preferably, the particle size of the nano-alumina is 3 nanometers.

[0043] More preferably, the welding wire used for brazing in step F is titanium wire.

[0044] Furthermore, the lengths of the casting pipe 2 and the venting pipe 6 are determined according to the following method:

[0045] Based on the three-dimensional model data obtained in step A, determine the pressure value p that matches the casting shrinkage of the wear-resistant white cast iron. Specifically, import the three-dimensional model data obtained in step A into the casting simulation software. Here, the casting simulation software is MAGMASOFT. The software calculates the pressure value p that matches the casting shrinkage of the wear-resistant white cast iron through simulation.

[0046] The height L from the gate surface to the top of the casting is determined based on the pressure value P, where L = P / (ρg), and ρ is the density of wear-resistant white cast iron (BTMCr15), ρ = 7800 kg / m³. 3 g is the acceleration due to gravity, g = 9.801 m / s² 2 ;

[0047] The lengths of the casting pipe 2 and the venting pipe 6 are determined according to the height L.

[0048] This embodiment also provides a manufacturing apparatus for a catalytic oil slurry pump body liner, used to fix the above-mentioned casting system consisting of a pump body liner shell, a casting pipe, and a venting pipe brazed together. It includes at least a sand box 8 for accommodating the brazed pump body liner shell 4, the casting pipe 2, and the venting pipe 6. The inner wall of the sand box 8 is filled with quartz sand 12 between itself and the casting system. The sand box 8 is covered with a sand box cover 9 and fasteners are used to connect the sand box cover 9 and the sand box 8. The upper openings of the casting pipe 2 and the venting pipe 6 are exposed on the surface of the sand box cover 9, that is, the casting port 1 of the casting pipe 2 and the venting port 7 of the venting pipe 6 are exposed on the surface of the sand box cover 9. Specifically, the casting system, including the pump body lining shell 4, the casting pipe 2, and the venting pipe 6, prepared by the above method, is placed in the sand box 8. Quartz sand 12 is then filled into the sand box 8 to fix the casting system in place. The sand box cover 9 is then placed on the upper surface of the sand box 8 and fastened to the upper surface of the sand box 8 with fastener studs 10 and nuts 11, so that the casting port 1 and the venting port 7 are exposed on the surface of the sand box cover 9. The sand box cover 9 compacts the quartz sand 12 and completes the stable positioning of the casting system, preventing the pump body lining shell 4 from floating and shifting during die casting and ensuring the quality of die casting. At the same time, the sand box 8 and the quartz sand 12 also provide support for the casting system, preventing the casting system from cracking and being damaged during die casting.

[0049] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing a liner for a catalytic oil slurry pump body, characterized in that: In a pump body lining shell made of nano-alumina, wear-resistant white cast iron molten material is die-cast into the pump body lining shell of the oil slurry pump. After cooling, a pump body lining with a corundum ceramic layer on the surface is obtained. The corundum ceramic layer and the wear-resistant white cast iron are metallurgically bonded. The fabrication and casting of the pump body lining shell includes the following steps: A. Perform three-dimensional parametric modeling of the pump body lining; B. Prepare a wax model: Import the three-dimensional model data obtained in step A into a 3D printer and print to prepare a wax model. C. Prepare a nano-alumina coating: Spray nano-alumina slurry onto the surface of the wax model obtained in step B to a set thickness, and after drying, form a nano-alumina coating on the surface of the wax model. The nano-alumina has a particle size of 3 nanometers, and the nano-alumina coating has a thickness of 0.3~0.5 mm. D. In step C, the set position of the wax mold sprayed with nano alumina slurry is removed to form a reserved casting connection port and a venting connection port for casting. E. The wax mold coated with nano-alumina slurry obtained in step D is dewaxed and sintered to obtain a hollow corundum ceramic structure pump body lining shell; dewaxing is completed during the sintering heating process; during the sintering operation, as the temperature rises, the wax mold gradually melts and flows out from the casting connection port, and is transported out and recycled through the pipe in the sintering furnace. After the temperature rises to the set temperature, the nano-alumina coating is transformed into a corundum ceramic structure. During this process, the position of the pump body lining shell remains fixed. F. Take the corundum ceramic structure pump body liner shell obtained in step E, and braze a casting pipe and a venting pipe of the same material as the pump body liner shell to the casting connection port and the venting connection port respectively, to obtain a pump body liner shell with a casting system. H. The wear-resistant white cast iron molten liquid is pressure cast from the casting pipe into the pump body lining shell by pressure casting, and the pump body lining billet is obtained after cooling to room temperature. I. Remove the casting pipe and vent pipe from the pump body lining billet obtained in step H, and braze the broken ends with titanium wire to make them flush, so as to obtain a pump body lining with a corundum ceramic layer on the surface that is metallurgically bonded to the wear-resistant white cast iron core.

2. The method for manufacturing a catalytic slurry pump body liner according to claim 1, characterized in that: The welding wire used for brazing in step F is titanium wire.

3. The method for manufacturing a catalytic slurry pump body liner according to claim 1, characterized in that, The lengths of the casting pipe and the venting pipe are determined as follows: Determine the pressure value that matches the casting shrinkage of wear-resistant white cast iron based on the three-dimensional model data obtained in step A; Determine the height of the gate opening from the top of the casting based on the pressure value; The lengths of the casting pipe and the venting pipe are determined based on the height.

4. A manufacturing apparatus for a catalytic oil slurry pump body liner, used to fix the casting system described in any one of claims 2 to 3, which is composed of the pump body liner shell, the casting pipe, and the venting pipe brazed together, characterized in that: It includes at least one sand box for containing a pump body lining shell, a casting pipe and a venting pipe that are brazed together; the inner wall of the sand box and the casting system are filled with quartz sand, the sand box is covered with a sand box cover and the sand box is connected to the sand box with fasteners, and the upper openings of the casting pipe and the venting pipe are exposed on the surface of the sand box cover.

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