阅读说明：本技术 一种注塑机料桶金属保护层结构及生产方法 (Metal protective layer structure of injection molding machine charging basket and production method ) 是由 王家琦 杨庆松 张凯 于 2019-11-18 设计创作，主要内容包括：本发明公开了一种注塑机料桶金属保护层结构及生产方法,主要先取一金属内管进行清洁及打砂处理,以在金属内管内壁黏结合金粉末,并以适当温度重熔烧结形成合金层,再取一金属外管使其加热膨胀后套入金属内管紧密连接,接着从金属外管外壁车削部分壁厚以修正偏心合乎标准口径,最后对合金层内壁打磨抛光,而制备成耐磨、耐腐蚀、高光洁度的注塑机金属料桶。本发明与现有技术相比的优点在于：解决目前市埸氮化、镀铬产品存在氮化层偏薄,及离心铸造料桶产品容易出现裂纹及麻坑,导致产品色度的问题,大幅提高料桶使用周期、节约制作成本及提高性价比。(The invention discloses a metal protective layer structure of a charging basket of an injection molding machine and a production method thereof, wherein a metal inner tube is cleaned and sanded firstly, so that gold powder is bonded on the inner wall of the metal inner tube, and is remelted and sintered at a proper temperature to form an alloy layer, a metal outer tube is taken to be sleeved into the metal inner tube for tight connection after being heated and expanded, then partial wall thickness is turned from the outer wall of the metal outer tube to correct eccentricity to meet standard caliber, and finally the inner wall of the alloy layer is sanded and polished, so that the metal charging basket of the injection molding machine with wear resistance, corrosion resistance and high smoothness is prepared. Compared with the prior art, the invention has the advantages that: the problems that nitriding layers of existing nitriding and chromium plating products in the market are thin, cracks and pits easily occur in centrifugally cast charging basket products, and the product chromaticity is caused are solved, the service cycle of the charging basket is greatly prolonged, the manufacturing cost is saved, and the cost performance is improved.)

1. The utility model provides an injection molding machine storage bucket metal protection layer structure, includes pushing away material (4) of injection molding machine, its characterized in that: the outside of the material pushing part (4) of injection molding machine is cup jointed and is equipped with metal inner tube (1), be equipped with alloy-layer (2) on the inner wall of metal inner tube (1), be equipped with one bonding portion (21) in alloy-layer (2) at least, bonding portion (21) are established to combine to form through a plurality of alloy powder (22), alloy powder (22) include a plurality of high rigidity metal powder (221) and with corrosion-resistant metal powder (222) that high rigidity metal powder mixes the formation, the outside of metal inner tube (1) is cup jointed and is equipped with metal outer tube (3).

2. The metal protective layer structure of the charging basket of the injection molding machine according to claim 1, wherein: the high-hardness metal powder (221) is set to 30 to 60% by weight, and the corrosion-resistant metal powder (222) is set to 40 to 70% by weight.

3. The metal protective layer structure of the charging basket of the injection molding machine according to claim 2, wherein: the high-hardness metal powder (221) is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion-resistant metal powder (222) is one of nickel, cobalt, or a combination thereof.

4. The metal protective layer structure of the charging basket of the injection molding machine according to claim 1, wherein: the inner diameter of the metal inner pipe (1) is set to be 12mm to 127 mm.

5. The metal protective layer structure of the charging basket of the injection molding machine according to claim 1, wherein: the thickness of the alloy layer (2) is set to be 0.1mm to 2 mm.

6. The metal protective layer structure of the charging basket of the injection molding machine according to claim 1, wherein: the grain size of the alloy layer (2) is set to 9-12 levels.

7. A metal protective layer structure of a charging basket of an injection molding machine and a production method are characterized in that: the method comprises the following steps:

(a) purifying the inner wall surface of the metal inner pipe (1);

(b) uniformly spraying an annular air nozzle (62) on the inner wall of the metal inner tube (1) to form a bonding part (21);

(c) uniformly spraying a plurality of alloy powders (22) containing a plurality of high-hardness metal powders (221) and a plurality of corrosion-resistant metal powders (222) mixed with the high-hardness metal powders (221) on the bonding part (21) by using an annular powder spraying nozzle (72);

(d) heating the metal inner tube (1) to remelt the bonding part (21) and the alloy powder (22) to form an alloy layer (2);

(e) taking and heating the metal outer pipe (3), sleeving the metal outer pipe (3) outside the metal inner pipe (1) when the metal outer pipe (3) is thermally expanded, and tightly connecting the metal outer pipe (3) with the metal inner pipe (1) after the metal outer pipe (3) is cooled and contracted;

(f) modifying the outer wall of the metal outer pipe (3) to enable the section of the metal inner pipe (1) and the section of the metal outer pipe (3) to form a concentric circle;

(g) and grinding and polishing the inner wall of the alloy layer (2).

8. The injection molding machine charging basket metal protection layer structure and the production method thereof according to claim 7, wherein: and (e) reserving a turning layer outside the metal outer pipe (3).

9. The injection molding machine charging basket metal protection layer structure and the production method thereof according to claim 7, wherein: the high-hardness metal powder (221) is 30 to 60 wt%, the corrosion-resistant metal powder (222) is 40 to 70 wt%, the high-hardness metal powder (221) is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion-resistant metal powder (222) is one of nickel, cobalt, or a combination thereof.

10. The injection molding machine charging basket metal protection layer structure and the production method thereof according to claim 7, wherein: the roughness of the inner wall of the alloy layer (2) after grinding and polishing is less than or equal to 0.4 mu m, and the thickness of the alloy layer (2) is 0.1mm to 2 mm.

Technical Field

The invention relates to the technical field of industrial metal manufacturing equipment, in particular to a charging basket metal protective layer structure of an injection molding machine and a production method.

Background

Injection molding is a process for producing parts made of thermoplastic or thermosetting plastic, wherein when plastic is heated and melted into fluid in a charging basket of an injection molding machine, the molten plastic is compressed and moved forward under the pressure of a plunger or a screw, and then injected into a closed mold with a low temperature at a fast speed through a nozzle at the front end of the charging basket, and after a certain period of cooling and shaping, the mold is opened to obtain a product, the existing injection molding machine produces a large amount of living goods, electronic, automobile and medical parts, the application range is wide, in order to improve the production quality and durability, additives containing fire retardants, glass fibers, stone powder or modifiers are commonly used, and the raw materials with abrasion and corrosion properties are heated and melted in the charging basket and then are subjected to high-pressure injection molding, but the raw materials containing hard particles of the additives can generate high abrasion between the screw and the charging basket, the conventional common method for manufacturing the charging basket of the injection molding machine has a nitriding (ion nitriding) treatment method or a centrifugal casting method, wherein the nitriding treatment method mostly uses cross-red or cross-black steel as a base material, an effective nitriding diffusion layer is only about 0.2 mm-0.5 mm, a hardness layer is thin, and the service life is short, while the thickness of an alloy layer of the centrifugal casting method can reach 4 mm-5 mm, but the thickness of the alloy layer cannot be accurately controlled in the casting process, so that the thickness is not uniform, about 50% of the alloy layer needs to be processed and ground, the material cost is high, and because the alloy powder has different specific gravity and is influenced by centrifugal force, components with large specific gravity are concentrated on the periphery, and metals, gases, impurities and the like with light specific gravity are concentrated on the inner side, so that the quality of the alloy layer is deteriorated, therefore, a manufacturing method for manufacturing the charging basket of the injection molding machine with high cost performance is lacked at present, these problems remain to be solved, so improvement is required.

Disclosure of Invention

The invention aims to overcome the technical defects and provide a metal protective layer structure of a charging basket of an injection molding machine and a production method thereof, wherein the metal protective layer structure has the advantages of high hardness, corrosion resistance, reusability, lower manufacturing cost, better material pipe quality and the like.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: the utility model provides an injection molding machine storage bucket metal protection layer structure, pushes away the material piece including the injection molding machine, the outside that pushes away the material piece of injection molding machine is cup jointed and is equipped with the metal inner tube, be equipped with the alloy-layer on the inner wall of metal inner tube, be equipped with a bonding portion in the alloy-layer at least, bonding portion establishes to combine to form through a plurality of alloy powder, the alloy powder includes a plurality of high rigidity metal powder and mixes the corrosion-resistant metal powder who forms with high rigidity metal powder, the outside of metal inner tube is cup jointed and is equipped with the metal outer tube.

As a refinement, the weight percentage of the high-hardness metal powder is set to 30% to 60%, and the weight percentage of the corrosion-resistant metal powder is set to 40% to 70%.

In an improvement, the high-hardness metal powder is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion-resistant metal powder is one of nickel, cobalt, or a combination thereof.

As a modification, the inner diameter of the metal inner pipe is set to 12mm to 127 mm.

As a refinement, the thickness of the alloy layer is set to 0.1mm to 2 mm.

As a refinement, the grain size of the alloy layer is set to grade 9 to 12.

A metal protective layer structure of a charging basket of an injection molding machine and a production method thereof comprise the following steps:

(a) purifying the inner wall surface of the metal inner pipe;

(b) uniformly spraying an adhesive part on the inner wall of the metal inner tube by using an annular air nozzle;

(c) uniformly spraying a plurality of alloy powders containing a plurality of high-hardness metal powders and a plurality of corrosion-resistant metal powders mixed with the high-hardness metal powders on the bonding part by using an annular powder spraying nozzle;

(d) heating the metal inner pipe to remelt the bonding part and the alloy powder to form an alloy layer;

(e) taking and heating the metal outer pipe, sleeving the metal outer pipe outside the metal inner pipe when the metal outer pipe is thermally expanded, and tightly connecting the metal outer pipe with the metal inner pipe after the metal outer pipe is cooled and contracted;

(f) modifying the outer wall of the metal outer pipe to enable the section of the metal inner pipe and the section of the metal outer pipe to form a concentric circle;

(g) and grinding and polishing the inner wall of the alloy layer.

As a modification, a turning layer is reserved outside the metal outer pipe in the step (e).

In an improvement, the high hardness metal powder is 30 to 60 weight percent, the corrosion resistant metal powder is 40 to 70 weight percent, the high hardness metal powder is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion resistant metal powder is one of nickel, cobalt, or a combination thereof.

As an improvement, the roughness of the inner wall of the alloy layer after grinding and polishing is less than or equal to 0.4 μm, and the thickness of the alloy layer is 0.1mm to 2 mm.

Compared with the prior art, the invention has the advantages that: the problems that the service life of a nitrided steel material barrel of a traditional common injection molding machine is short, holes and cracks are easy to generate on a double-alloy coating on the inner wall of the barrel by a centrifugal casting method, and more materials are consumed are solved, and the alloy layer with high strength, high density, high finish degree, wear resistance and corrosion resistance is generated, so that the product performance is improved, and the production cost is reduced.

Drawings

FIG. 1 is a perspective view of a metal protection layer structure of a charging basket of an injection molding machine and a production method thereof.

FIG. 2 is a sectional view taken along line A-A of FIG. 1 of a metal protection layer structure of a charging basket of an injection molding machine and a production method thereof according to the present invention.

FIG. 3 is a structural block diagram of a metal protection layer structure of a charging basket of an injection molding machine and a production method thereof.

FIG. 4 is a flow chart of a method for manufacturing the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 5 is a schematic view of the inner tube cleaning of the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 6 is a schematic diagram of inner tube spraying of the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 7 is a schematic diagram of the metal protective layer structure of the charging basket of the injection molding machine and the alloy powder spraying of the production method.

FIG. 8 is a schematic diagram of alloy layer hot melting of the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 9 is a schematic diagram of the connection of the inner pipe and the outer pipe of the metal protective layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 10 is a view showing the completion of the connection of the inner and outer pipes in the structure of the metal protection layer of the charging basket of the injection molding machine and the production method of the invention.

FIG. 11 is a schematic view of a modified eccentricity of a metal protection layer structure of a charging basket of an injection molding machine and a production method thereof.

FIG. 12 is a schematic diagram of the polishing and burnishing of the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

FIG. 13 is a diagram of the usage status of the metal protection layer structure of the charging basket of the injection molding machine and the production method thereof.

As shown in the figure: 1. the metal inner tube, 2, an alloy layer, 21, a bonding part, 22, alloy powder, 221, high-hardness metal powder, 222, corrosion-resistant metal powder, 3, a metal outer tube, 4, a pushing piece, 5, a workbench, 6, a miniature soldering flux spraying device, 61, a soldering flux conveying tube, 62, an annular air nozzle, 63, a first air nozzle, 7, a miniature alloy powder spraying device, 71, a powder conveying tube, 72, an annular powder spraying nozzle, 73, a second air nozzle, 8, a workbench, 81, an induction coil, 91, a lathe, 92 and a tube grinding machine.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The invention provides a metal protection layer structure of a charging basket of an injection molding machine, which comprises a pushing part 4 of the injection molding machine, wherein a metal inner tube 1 is sleeved on the outer side of the pushing part 4 of the injection molding machine, an alloy layer 2 is arranged on the inner wall of the metal inner tube 1, at least one bonding part 21 is arranged in the alloy layer 2, the bonding part 21 is formed by combining a plurality of alloy powders 22, the alloy powders 22 comprise a plurality of high-hardness metal powders 221 and corrosion-resistant metal powders 222 formed by mixing with the high-hardness metal powders, and a metal outer tube 3 is sleeved on the outer side of the metal inner tube 1.

The high-hardness metal powder 221 is set to 30 to 60% by weight, and the corrosion-resistant metal powder 222 is set to 40 to 70% by weight.

The high-hardness metal powder 221 is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion-resistant metal powder 222 is one of nickel, cobalt, or a combination thereof.

The inner diameter of the metal inner pipe 1 is set to 12mm to 127 mm.

The alloy layer 2 is set to a thickness of 0.1mm to 2 mm.

The grain size of the alloy layer 2 is set to 9 to 12 grades.

A metal protective layer structure of a charging basket of an injection molding machine and a production method thereof comprise the following steps:

a, purifying the inner wall surface of the metal inner pipe 1;

b, uniformly spraying an adhesive part 21 on the inner wall of the metal inner tube 1 by using an annular air nozzle 62;

c, uniformly spraying a plurality of alloy powders 22 containing a plurality of high-hardness metal powders 221 and a plurality of corrosion-resistant metal powders 222 mixed with the high-hardness metal powders 221 on the bonding part 21 by using an annular powder spraying nozzle 72;

d heating the metal inner tube 1 to remelt the bonding portion 21 and the alloy powder 22 to form an alloy layer 2;

e, taking and heating the metal outer pipe 3, sleeving the metal outer pipe 3 outside the metal inner pipe 1 when the metal outer pipe 3 is thermally expanded, and tightly connecting the metal outer pipe 3 with the metal inner pipe 1 after the metal outer pipe 3 is cooled and contracted;

f, correcting the outer wall of the metal outer pipe 3 to enable the section of the metal inner pipe 1 and the section of the metal outer pipe 3 to form a concentric circle;

g, grinding and polishing the inner wall of the alloy layer 2.

And e, reserving a turning layer outside the metal outer pipe 3.

The high-hardness metal powder 221 is 30 to 60 wt%, the corrosion-resistant metal powder 222 is 40 to 70 wt%, the high-hardness metal powder 221 is one of tungsten carbide, chromium, iron, or a combination thereof, and the corrosion-resistant metal powder 222 is one of nickel, cobalt, or a combination thereof.

The roughness of the inner wall of the alloy layer 2 after grinding and polishing is less than or equal to 0.4 mu m, and the thickness of the alloy layer 2 is 0.1mm to 2 mm.

The working principle of the invention is as follows: referring to fig. 1 to 4 and 13, a perspective view to a block flow diagram and a use state diagram of an embodiment of the present invention are shown, and it can be clearly seen from the drawings and understood that the structure of the present invention can achieve the advantages of high hardness, corrosion resistance, reusability, low manufacturing cost, good quality of the barrel according to the corresponding cooperation of the structure, and the following detailed description will be given to the following description, and referring to fig. 1 to 13, the perspective view to the use state diagram of the embodiment of the present invention, in order to provide the barrel of the injection molding machine with the above advantages, the key point is how to form the barrel, so the steps of the production method are specifically as follows: step (a), referring to fig. 5, firstly, using a steel pipe made of alloy steel as the metal inner pipe 1 (for example, black cross steel (SACM645) with the length of not more than 10m and the inner diameter of 12 mm-127 mm as the metal inner pipe 1), cleaning the inner wall of the metal inner pipe 1 with an organic solvent (for example, ethanol acetone), then removing the oxide on the inner wall of the metal inner pipe 1 by adopting a sand blasting mode to ensure that the inner wall of the metal inner pipe 1 has no impurities, and step (b), referring to fig. 6, fixing the metal inner pipe 1 on a worktable 5 to rotate at a constant speed, and spraying by using a miniature soldering flux spraying device 6, wherein the miniature soldering flux spraying device 6 inputs soldering flux by using a soldering flux conveying pipe 61 and temporarily stores the soldering flux in an annular air nozzle 62, then introducing high-pressure gas by using a first air nozzle 63 to ensure that the soldering flux is uniformly sprayed in a radial shape by the annular air nozzle 62, and the miniature soldering flux spraying device 6(, the invention can form the bonding part 21 on the inner wall of the metal inner tube 1, thereby improving the defect that the prior spraying method causes the condensation of the soldering flux and the alloy powder 22 to generate holes, and also solving the problem that the direct soldering flux coating method causes the large dosage and the uneven thickness, and the invention uses the annular air nozzle 62 to blow out stable airflow, can effectively control the thickness of the bonding part 21, can increase the spraying amount of the soldering flux under the condition of ensuring the constant working quality of the components and the concentration of the soldering flux, further increases the forming thickness (can be increased to 2mm) of the subsequent alloy layer 2, and the step (c) is as shown in figure 7, the miniature alloy powder spraying device 7 is deeply inserted into the metal inner tube 1, and similarly, the alloy powder 22 is input by the powder conveying pipe 71 and temporarily stored in the annular powder spraying nozzle 72, and then the second air nozzle 73 is used to introduce high-pressure gas, so that the annular powder spraying nozzle 72 uniformly and radially sprays the alloy powder, the micro-alloy powder spraying device 7 (or the ring-shaped powder nozzle 72) is advanced at a fixed speed to control the spraying amount of the alloy powder 22 to reach a predetermined thickness (1mm to 2mm), wherein the alloy powder 22 comprises a certain amount of high-hardness metal powder 221 and corrosion-resistant metal powder 222 mixed with the high-hardness metal powder 221, the high-hardness metal powder 221 can be tungsten carbide, chromium or iron, and is 30 to 60 weight percent, and the corrosion-resistant metal powder 222 can be nickel or cobalt, and is 40 to 70 weight percent (the proportion can be adjusted to strengthen the wear-resistant or corrosion-resistant performance), so that the combination of the alloy powder 22 can be nickel-based tungsten carbide, iron-based chromium and the like, for example, the nickel-based tungsten carbide is selected from superfine powder with the particle size of about 60 μm, and has high purity and uniform particle size, The dispersion is good, the alloy powder can be uniformly mixed with high-hardness metal powder 221 (nickel), the alloy layer 2 has higher hardness due to higher tungsten carbide content, but the possibility of crack formation during subsequent remelting is increased due to excessive tungsten carbide, so the tungsten carbide content is not more than 60%, therefore, the hardness of the alloy layer 2 containing tungsten carbide after molding can reach more than HRC62, and if the tungsten carbide proportion is properly increased, the HRC70 standard can be further reached, step (d), referring to the graph shown in FIG. 8, the metal inner tube 1 completing the bonding action of the alloy powder 22 is placed on a working base 8, the advancing speed, the rotating speed and the output power of the metal inner tube 1 passing through an induction coil 81 are set according to the tube wall thickness and the preset thickness of the alloy layer 2, the remelting temperature is controlled to be 1020 ℃ to 1200 ℃, and the high-temperature resistance characteristic meets the condition of the working temperature (not less than 450 ℃) of an injection molding machine, for example, if the wall thickness of the inner metal tube 1 is less than or equal to 10mm and the predetermined thickness of the alloy layer 2 is 0.2mm to 2mm, the advancing speed is based on 17cm/min, the rotating speed is based on 210rpm, and the output power is based on 150kw, so that the adhesive part 21 and the alloy powder 22 are remelted to form the alloy layer 2, and the alloy layer 2 has the wear-resisting property of the high-hardness metal powder 221 and the corrosion-resisting property of the corrosion-resisting metal powder 222, and the steps (e) and (e1), as shown in fig. 9 and 10, another carbon steel tube with any carbon content is taken as the outer metal tube 3 (for example, aluminum-chromium-molybdenum alloy steel), and the outer metal tube 3 is heated at 600 degrees centigrade to deform due to the effect of thermal expansion and cold contraction until the inner diameter of the outer metal tube 3 is slightly larger than the outer diameter of the inner metal tube 1 (larger than 0.01mm to 0.05mm), the outer metal pipe 3 is quickly sleeved into the inner metal pipe 1, and when the outer metal pipe 3 is cooled, the outer metal pipe 3 can be tightly combined with the outer wall of the inner metal pipe 1 due to the effect of expansion with heat and contraction with cold, so that the outer metal pipe cannot relatively rotate, and the thickness of the outer metal pipe 3 is reserved to be 2mm, so that the outer metal pipe 3 can be used as a turning layer for subsequently correcting the eccentric action, wherein before the outer metal pipe 3 is heated, if the outer diameter of the inner metal pipe 1 is larger than the inner diameter of the outer metal pipe 3, the outer wall of the inner metal pipe 1 is firstly polished, for example, the outer diameter of the inner metal pipe 1 after polishing is only 0.05mm larger than the inner diameter of the outer metal pipe 3, so as to keep the interference value within 0.05mm, (interference fit refers to a means for generating elastic pressure between the surfaces of parts after assembly depending on the interference value of a shaft and a hole, thereby obtaining fastening connection, turning the outer wall turning layer part of the metal outer pipe 3 which completes the combination action, so that the metal inner pipe 1 and the metal outer pipe 3 keep higher concentricity, namely the section of the metal inner pipe 1 and the section of the metal outer pipe 3 form a concentric circle, and the outer wall of the metal outer pipe 3 reaches the required size, step (g), as shown in figure 12, arranging the metal outer pipe 3 which completes the combination action on a pipe grinding machine 92, grinding off the reserved thickness of an alloy layer 2, polishing the inner wall roughness (to be less than or equal to 0.4 μm) by fine sand, although the design of the alloy layer 2 can reduce the inner diameter of a charging basket, the alloy layer 2 expands in the remelting and sintering manufacturing process, and extrudes the inner wall of the metal inner pipe 1, so that the inner diameter can be expanded again while the density of the metal inner pipe 1 is increased, the thickness of the alloy layer 2 can be compensated, and finally, the processing and polishing are carried out the thickness, the double-alloy-layer inner wall structure of the charging basket of the injection molding machine can be operated within the range of less than or equal to 0.1mm, materials are saved, and finally an instrument is used for detecting the inner wall to ensure that no pore or crack exists, so that the manufacturing of the inner wall of the double-alloy-layer 2 of the charging basket of the injection molding machine is completed, the charging basket of the injection molding machine disclosed by the invention is combined with the state of the material pushing piece 4, as shown in a figure 13, in addition, the grinding action can control the grain size to be 9-12-grade ultra-fine grain size, the compactness of the charging basket is improved and the mechanical property is improved by reducing the grain size, the pipe wall is smoother and cannot be blocked with powder after being polished, and the above is only an embodiment of the invention, so that the double-alloy-layer inner wall structure of the: firstly, the thickness of the alloy layer 2 can reach 0.2 mm-2 mm, the alloy layer 2 with the thickness of 0.1 mm-1.5 mm can be obtained after processing, grinding and polishing, the grinding amount is less, and the production cost can be saved; secondly, by uniformly spraying the alloy powder 22 and the alloy layer 2 with properly controlled temperature and sintering time, holes and cracks are not easy to generate, and a high-quality injection molding machine charging basket with good finish, wear resistance and corrosion resistance can be formed; and thirdly, during maintenance, the inner pipe can be taken out in a mode of heating the metal outer pipe 3 (based on the principle that the expansion coefficient of the metal inner pipe 1 is smaller than that of the metal outer pipe 3), or the metal inner pipe 1 is taken out in a linear cutting mode and sleeved into the metal outer pipe 1 again after maintenance, so that the metal inner pipe can be recycled, the whole charging basket does not need to be replaced when the charging basket is worn, and the purpose of greatly saving the cost is achieved.

The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the drawings are only one embodiment of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.