Grinding cylinder, grinding machine and manufacturing method of grinding cylinder

Abstract

The invention provides a grinding cylinder, a grinding machine and a manufacturing method of the grinding cylinder. The grinding cylinder comprises a shell, and the shell comprises a liquid inlet which is a through hole penetrating through the inner surface and the outer surface of the shell; the liquid outlet is a through hole penetrating through the inner surface and the outer surface of the shell; the liquid inlet and the liquid outlet are arranged at an interval; the outer surface of the middle shell is provided with convex edges, and the convex edges protrude outwards from the outer surface of the middle shell; a gap is formed between the rib and the inner surface of the shell; the middle shell is fixedly connected with the inner shell; the outer shell, the middle shell and the inner shell are sequentially arranged from outside to inside. The grinding cylinder is good in heat dissipation effect and convenient to machine.

Description

[Technical field]

[0001] The present invention relates to the field of grinding technology, and in particular to a grinding cylinder, a grinding machine and a method for manufacturing the grinding cylinder. [Background technology]

[0002] The grinding machine usually drives the grinding medium to move at high speed in a fixed space (generally designed as a "grinding cylinder" with a relatively independent space) through the grinding rotor, so that the grinding medium continuously squeezes or collides with the material to be ground during the high-speed movement, causing the material to be broken and then smaller and smaller. When the ground material is squeezed and broken, if it reaches a certain size requirement, the grinding is stopped; then the ground material and the grinding medium are separated by some means.

[0003] In this process, due to the high-speed collision between the grinding media and the material to be ground, and the grinding cylinder is a relatively closed space, the grinding cylinder is prone to generate a large amount of heat energy during the grinding process.

[0004] In the prior art, oil cooling or water cooling is generally used to cool the grinding cylinder. For example:

[0005] The patent document with patent number CN201720077703.3 discloses a cooling device for a sand mill, including a horizontal inner cylinder and an outer cylinder sleeved outside the inner cylinder, the inner cylinder and the outer cylinder together form a cylindrical cooling chamber, a partition spirally wrapped around the outside of the inner cylinder is arranged between the inner cylinder and the outer cylinder, the partition divides the cooling chamber into a cooling water channel spirally wrapped around the outside of the inner cylinder from front to back, the front end of the outer cylinder is provided with a water inlet connected to the cooling water channel, and the rear end is provided with a water outlet connected to the cooling water channel.

[0006] This technical solution has been tested in practice. Although it can partially solve the technical problem of grinding cylinder cooling, the following technical problems still exist: for example, since the cooling water channel is set up by the partition, the grinding cylinder in contact with the partition is not effectively cooled; in addition, the design of the partition also squeezes the space between the outer cylinder and the inner cylinder, resulting in a reduction in the volume of liquid actually flowing between the inner cylinder and the outer cylinder, which in turn leads to an insufficient cooling effect.

[0007] The patent document with patent number CN201821891990.2 discloses a heat dissipation type horizontal sand mill, including a sand mill frame, a material storage box is arranged at the upper end of the sand mill frame, a material discharge port is arranged at the upper end of the material storage box, a sand mill cylinder is arranged at the side end of the material storage box, a steam pressure type thermostat is arranged at the upper end of the sand mill cylinder, a compressor is arranged at one side of the steam pressure type thermostat, a feed port is arranged at one side of the compressor, a stirring motor support is arranged at one side of the sand mill cylinder, and a stirring motor is arranged at the upper end of the stirring motor support. A battery is arranged on one side of the stirring motor, a base is arranged on the lower end surface of the sand mill frame, a stirring shaft is arranged inside the sand mill cylinder, a stirring wheel is arranged on the surface of the stirring shaft, a protective net is arranged above the stirring shaft, a condenser is arranged above the protective net, an evaporator is arranged on one side of the condenser, the compressor, the condenser and the evaporator are all connected through a return air pipe, and the stirring motor, the compressor, the condenser, the evaporator, the steam pressure thermostat and the battery are all connected through wires.

[0008] This technical solution is to design a condenser separately, which not only occupies the space of other devices, but also the cooling effect of the condenser cannot evenly cover the entire grinding cylinder. Not only is the structural design complicated, but the cooling effect is also uneven. [Summary of the invention]

[0009] In view of the above technical problems in the prior art, the present invention provides a grinding cylinder, including a grinding cylinder, including: a shell, the shell including:

[0010] a liquid inlet, which is a through hole penetrating the inner surface and the outer surface of the shell;

[0011] The liquid outlet is a through hole penetrating the inner and outer surfaces of the shell; the liquid inlet and the liquid outlet are spaced apart;

[0012] A middle shell; an inner shell, wherein the middle shell and the inner shell are fixedly connected;

[0013] The outer shell, the middle shell and the inner shell are arranged in sequence from the outside to the inside;

[0014] A convex ridge is arranged between the middle shell and the outer shell, and a height of the convex ridge is smaller than a distance between an outer surface of the middle shell and an inner surface of the outer shell.

[0015] It should be noted that the outer shell, the middle shell and the inner shell are in the shape of hollow rings, which are shell structures with a hollow interior, and the cross-sections are all circular or approximately circular.

[0016] It should be noted that a ridge is provided between the middle shell and the outer shell, and the ridge can be provided on the outer surface of the middle shell or on the inner surface of the outer shell. During the setting process, whether the ridge is provided on the outer surface of the middle shell or on the inner surface of the outer shell, it is equivalent to providing the ridge between the outer shell and the middle shell.

[0017] It should be noted that the ridge is arranged on the inner surface of the shell, and the ridge and the shell may be of an integrated design. During the processing, the two are processed into an integral body by a lathe or a milling machine.

[0018] Of course, the convex ridge can also be fixedly connected to the inner surface of the shell by welding, gluing, riveting, interference fit and other connection methods.

[0019] Similarly, the ridge is arranged on the outer surface of the middle shell, and the ridge and the middle shell can be of integrated design. During the processing, the two are processed into one piece by a lathe or a milling machine.

[0020] Of course, the convex ridge may also be fixedly connected to the outer surface of the middle shell by welding, gluing, riveting, interference fit or the like.

[0021] Furthermore, when the ridges are arranged on the outer surface of the middle shell, the ridges protrude outward from the outer surface of the middle shell; and there is a gap between the ridges and the inner surface of the outer shell.

[0022] The gap is the height of the ridge and the height difference between the inner surface of the outer shell and the outer surface of the middle shell.

[0023] It should be noted that the convex ridge is fixedly connected to the outer surface of the middle shell, and the height of the convex ridge protruding from the outer surface of the middle shell is the height of the convex ridge.

[0024] The height difference between the inner surface of the outer shell and the outer surface of the middle shell is the minimum straight-line distance between the inner surface of the outer shell and the outer surface of the middle shell.

[0025] Furthermore, the inner surface of the outer shell is provided with a ridge, and the ridge extends from the inner surface of the outer shell; and there is a gap between the ridge and the outer surface of the middle shell.

[0026] It should be noted that the ridge is fixedly connected to the inner surface of the shell, and the height of the ridge protruding from the inner surface of the shell is the height of the ridge. At this time, since the ridge is arranged on the inner surface of the shell, it extends from the inner surface of the shell to the inside of the cavity formed by the shell.

[0027] Furthermore, the convex ridge is spirally wound around the outer surface of the middle shell.

[0028] It should be noted that, in this case, the ridges extend on the outer surface of the middle shell, and the overall shape is a spiral shape, for example: based on the axial center line of the entire middle shell, the outer surface of the middle shell rises or falls in a spiral shape.

[0029] Furthermore, the convex ridge is spirally wound around the inner surface of the shell.

[0030] It should be noted that, in this case, the ridge extends on the inner surface of the shell, and the overall shape is a spiral shape, for example: based on the axial center line of the entire shell, the inner surface of the shell rises or falls in a spiral shape.

[0031] It should be further explained that when the ridge is spiral, the ridge forms a complete flow channel, which can regulate the coolant flowing into it into a spiral flow state.

[0032] Furthermore, the number of the ridges may be greater than or equal to 2, and different ridges are arranged at intervals on the outer surface of the middle shell to form a plurality of independent flow channels. A guide plate is arranged between the independent flow channels, and the guide is also arranged on the outer surface of the middle shell. The guide plate plays a role of guiding flow, and the guide plate is connected between different ridges. The independent ridges are connected to form a flow channel that flows with each other.

[0033] The shape and position of the guide plate are not specifically limited or agreed upon herein and can be adjusted according to specific actual conditions.

[0034] The cross section of the convex ridge is triangular or quadrilateral.

[0035] It should be noted that the cross section of the ridge refers to the cross section of the portion of the ridge that protrudes outward from the inner surface of the outer shell or protrudes outward from the outer surface of the middle shell.

[0036] It should be noted that the cross-section of the ridge is a triangle or a quadrilateral, which can be appropriately expanded in the present application. In the actual processing process, it can be a shape roughly close to a triangle, or roughly close to a quadrilateral, or it can be a triangle or quadrilateral with chamfers set at the connection of each side of the triangle or quadrilateral; or the sides of the triangle or quadrilateral may not be straight lines, but lines with a certain curvature.

[0037] It should be noted that the height of the ridge is defined as the first length, the distance between the outer surface of the middle shell and the inner surface of the outer shell is defined as the second length, and the difference between the second length and the first length ranges from 0.1 mm to 1.8 mm.

[0038] It should be noted that the present application also includes: a front sealing ring, which is arranged on the front end surfaces of the outer shell and the middle shell; a rear sealing ring, which is arranged on the rear end surfaces of the outer shell and the middle shell; the front sealing ring, the rear sealing ring, the outer shell and the middle shell form a accommodating space.

[0039] It should be noted that the middle shell is also provided with a plurality of sealing grooves, and the sealing grooves cooperate with the front sealing ring and the rear sealing ring.

[0040] It should be noted that this application also includes:

[0041] A front end cover, which is arranged on the front end surfaces of the outer shell and the middle shell;

[0042] A rear end cover, which is arranged on the rear end surfaces of the outer shell and the middle shell;

[0043] The front end cover, the front sealing ring and the housing are connected in sequence;

[0044] The rear end cover, the rear sealing ring and the housing are connected in sequence.

[0045] The present application also provides a grinding machine, which includes a frame and a transmission device, wherein the transmission device is installed on the frame; and also includes any one of the above-mentioned grinding cylinders.

[0046] The present application also provides a method for manufacturing a grinding cylinder, comprising:

[0047] The middle shell is subjected to a heating treatment;

[0048] The heating temperature is greater than or equal to 200 degrees Celsius, and the heating time is greater than or equal to 30 minutes;

[0049] placing an inner shell into the middle shell;

[0050] Air-cooling the inner shell and the middle shell for at least 90 minutes;

[0051] Sleeve the outer shell onto the outer surface of the middle shell;

[0052] forming the grinding cylinder;

[0053] Wherein, the housing comprises:

[0054] a liquid inlet, which is a through hole penetrating the inner surface and the outer surface of the shell;

[0055] The liquid outlet is a through hole penetrating the inner and outer surfaces of the shell; the liquid inlet and the liquid outlet are spaced apart;

[0056] The middle shell and the inner shell are fixedly connected;

[0057] The outer shell, the middle shell and the inner shell are arranged in sequence from the outside to the inside;

[0058] A convex ridge is arranged between the middle shell and the outer shell, and a height of the convex ridge is smaller than a distance between an outer surface of the middle shell and an inner surface of the outer shell.

[0059] Optionally, the outer surface of the middle shell is provided with ridges, and the ridges protrude outward from the outer surface of the middle shell; and there is a gap between the ridges and the inner surface of the outer shell.

[0060] Optionally, the inner surface of the outer shell is provided with a ridge, and the ridge extends from the inner surface of the outer shell; and there is a gap between the ridge and the outer surface of the middle shell.

[0061] Optionally, the ridges are spirally wound around the outer surface of the middle shell.

[0062] Optionally, the number of the ridges is greater than or equal to 2, and different ridges are arranged at intervals on the outer surface of the middle shell; a guide plate is also provided on the outer surface of the middle shell, and the guide plate is connected between different ridges.

[0063] Optionally, the cross section of the ridge is triangular or quadrilateral.

[0064] Optionally, the height of the ridge is defined as a first length, the distance between the outer surface of the middle shell and the inner surface of the outer shell is defined as a second length, and the difference between the second length and the first length ranges from 0.1 mm to 1.8 mm.

[0065] Optionally, it also includes:

[0066] A front sealing ring, which is arranged on the front end surfaces of the outer shell and the middle shell;

[0067] A rear sealing ring, which is arranged on the rear end surfaces of the outer shell and the middle shell;

[0068] The front sealing ring, the rear sealing ring, the outer shell and the middle shell form a containing space.

[0069] Optionally, the middle shell is further provided with a plurality of sealing grooves, and the sealing grooves cooperate with the front sealing ring and the rear sealing ring.

[0070] Optionally, the grinding cylinder further comprises:

[0071] A front end cover, which is arranged on the front end surfaces of the outer shell and the middle shell;

[0072] A rear end cover, which is arranged on the rear end surfaces of the outer shell and the middle shell;

[0073] The front end cover, the front sealing ring and the housing are connected in sequence;

[0074] The rear end cover, the rear sealing ring and the housing are connected in sequence.

Brief Description of the Drawings

[0075] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 creative work, among which:

[0076] Figure 1 What is revealed is a structural diagram of a grinding cylinder;

[0077] Figure 2 What is revealed is Figure 1 The disassembled structure diagram of the grinding cylinder shown;

[0078] Figure 3 What is revealed is Figure 1 The cross-sectional structure diagram of the grinding cylinder shown;

[0079] Figure 4 What is revealed is Figure 1 A schematic diagram of the structure of the middle shell shown;

[0080] Figure 5 Disclosed is a schematic flow chart of a method for manufacturing a grinding cylinder. [Specific implementation method]

[0081] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0083] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0084] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0085] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0086] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 as well as Figure 5 , Figure 1 What is revealed is a structural diagram of a grinding cylinder; Figure 2 What is revealed is Figure 1 The disassembled structure diagram of the grinding cylinder shown; Figure 3 What is revealed is Figure 1 The cross-sectional structure diagram of the grinding cylinder shown; Figure 4 What is revealed is Figure 3 A schematic diagram of the structure of the enlarged view of the A region shown; Figure 5 Disclosed is a schematic flow chart of a method for manufacturing a grinding cylinder.

[0087] exist Figure 1In the embodiment, the grinding cylinder 01 includes an outer shell 03, a middle shell 05 and an inner shell 07. The outer shell 03, the middle shell 05 and the inner shell 07 are arranged in sequence from the outside to the inside. The outer shell 03 is a hollow ring-shaped shell, which is annular as a whole and has a certain height and extends in the longitudinal direction. There is a certain thickness between the inner ring 031 and the outer ring 033 of the outer shell 03. The outer shell 03 includes a liquid inlet 035 and a liquid outlet 037, which are through holes that penetrate the inner surface and the outer surface of the outer shell 01.

[0088] There is a certain interval between the liquid inlet 035 and the liquid outlet 037, that is, there is a certain distance between the two. For example, the liquid inlet 035 is arranged at the upper part of the shell 03, and the liquid outlet 037 is arranged at the lower part of the shell 03. The larger the position interval between the two, the longer the distance the cooling liquid flows in the subsequent cooling process, and the more sufficient the cooling effect.

[0089] It should be noted that the shapes of the liquid inlet 035 and the liquid outlet 037 are not limited, and the shapes can be circular, square, or other shapes.

[0090] The liquid inlet 035 or the liquid outlet 037 can be a straight hole structure that directly passes through the outer surface and the inner surface of the shell 03; or it can be a bent channel structure, but the outer surface and the inner surface of the shell 03 appear to have a hole structure.

[0091] The outer surface 051 of the middle shell 05 is provided with a ridge 053 , and the ridge 053 protrudes outward from the outer surface 051 ; there is a gap between the ridge 053 and the inner surface of the outer shell 03 .

[0092] The existence of the gap means that the highest point of the ridge 053 is not in contact with the inner surface of the housing 03. The ridge 053 may have various shapes, such as a square, a triangle, a polygon, etc., in cross section.

[0093] The ridges 053 may be integrally formed with the outer surface 051 of the middle shell 05, or may be connected together by screw connection, welding, or other connection methods. The ridges 053 may be arranged as channels on the outer surface 051 to facilitate the subsequent flow of coolant in the channels. There is no definite shape or method for setting the direction of the channels, as long as a complete channel for the flow of coolant can be formed.

[0094] and Figure 1Corresponding to the technical solution in, there is another embodiment, in which the ridge 053 is provided on the inner surface of the shell 03, and the ridge 053 extends inward from the inner surface of the shell 03 and extends along the cavity inward toward the shell 03. There is a gap between the ridge 053 and the outer surface of the middle shell 03.

[0095] The existence of the gap means that the highest point of the ridge 053 is not in contact with the outer surface of the middle shell 05. The ridge 053 may have various shapes, such as a square, a triangle, a polygon, etc., in cross section.

[0096] In one embodiment of the present application, the ridge 053 is spirally shaped on the outer surface of the middle shell 05 .

[0097] The front end surface of the outer shell 03 and the middle shell 05 is approximately

[0120] Step 5: Sleeve the outer shell onto the outer surface of the middle shell.

[0121] It should be noted that the heating temperature is greater than or equal to 220 degrees Celsius. In the actual selection process, it can be 220 degrees Celsius, 230 degrees Celsius, 240 degrees Celsius, 250 degrees Celsius, 260 degrees Celsius, 270 degrees Celsius, 300 degrees Celsius, 340 degrees Celsius, 380 degrees Celsius, 400 degrees Celsius, 5000 degrees Celsius and other parameters. The above parameters can be adjusted according to the actual situation, and can be freely selected under the premise of satisfying the heating temperature and operating efficiency.

[0122] It should be noted that the heating time can be 30 minutes, 35 minutes, 40 minutes, 4 minutes, 50 minutes, 70 minutes, 80 minutes, 120 minutes, 180 minutes, 200 minutes. The above parameters can be adjusted according to actual conditions and can be freely selected under the premise of satisfying the heating temperature and operating efficiency.

[0123] It should be noted that the air cooling time of the inner shell and the middle shell can be 90 minutes, 120 minutes, 150 minutes, 180 minutes, 210 minutes, 240 minutes, 260 minutes, 300 minutes, 350 minutes, 180 minutes, 210 minutes and 240 minutes. The above parameters can be adjusted according to actual conditions and can be freely selected under the premise of satisfying air cooling effect and operation efficiency.

[0124] It should be noted that, in a preferred embodiment, the middle shell 05 is made of aluminum metal, which has the characteristics of thermal expansion and contraction. The method adopted in this application is to first heat the middle shell 05 to expand it, then put the inner shell 07 into it, and then air cool it for a period of time. Through the above-mentioned principle of thermal expansion and contraction, the inner shell 07 and the middle shell 05 are finally installed. In this installation process, the process of assembling unnecessary connecting devices is avoided. The installation method is simple and efficient, and it is not easy to cause unnecessary destructive assembly and damage to the middle shell 05 and the inner shell 07.

[0125] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A grinding cylinder, characterized in that: include: A housing, the housing comprising: a liquid inlet, which is a through hole penetrating the inner surface and the outer surface of the shell; The liquid outlet is a through hole penetrating the inner and outer surfaces of the shell; the liquid inlet and the liquid outlet are spaced apart; Middle shell; An inner shell, the middle shell and the inner shell are fixedly connected; The outer shell, the middle shell and the inner shell are arranged in sequence from the outside to the inside; A convex ridge is arranged between the middle shell and the outer shell, and a height of the convex ridge is smaller than a distance between an outer surface of the middle shell and an inner surface of the outer shell.

2. The grinding cylinder according to claim 1, characterized in that The outer surface of the middle shell is provided with ridges, and the ridges protrude outward from the outer surface of the middle shell; there is a gap between the ridges and the inner surface of the outer shell.

3. The grinding cylinder according to claim 1, characterized in that The inner surface of the outer shell is provided with a ridge, and the ridge extends from the inner surface of the outer shell; and there is a gap between the ridge and the outer surface of the middle shell.

4. The grinding cylinder according to claim 2, characterized in that The convex ridge is spirally wound around the outer surface of the middle shell.

5. The grinding cylinder according to claim 2, characterized in that: The number of the ridges is greater than or equal to 2, and different ridges are arranged at intervals on the outer surface of the middle shell; a guide plate is also arranged on the outer surface of the middle shell, and the guide plate is connected between different ridges.

6. The grinding cylinder according to claim 1, characterized in that The cross section of the convex ridge is a triangle or a quadrilateral.

7. The grinding cylinder according to claim 1, characterized in that The height of the ridge is defined as a first length, the distance between the outer surface of the middle shell and the inner surface of the outer shell is defined as a second length, and the difference between the second length and the first length ranges from 0.1 mm to 1.8 mm.

8. The grinding cylinder according to claim 1, characterized in that Also includes: A front sealing ring, which is arranged on the front end surfaces of the outer shell and the middle shell; A rear sealing ring, which is arranged on the rear end surfaces of the outer shell and the middle shell; The front sealing ring, the rear sealing ring, the outer shell and the middle shell form a containing space.

9. The grinding cylinder according to claim 1, characterized in that: The middle shell is also provided with a plurality of sealing grooves, and the sealing grooves cooperate with the front sealing ring and the rear sealing ring.

10. The grinding cylinder according to claim 9, characterized in that Also includes: A front end cover, which is arranged on the front end surfaces of the outer shell and the middle shell; A rear end cover, which is arranged on the rear end surfaces of the outer shell and the middle shell; The front end cover, the front sealing ring and the housing are connected in sequence; The rear end cover, the rear sealing ring and the housing are connected in sequence.

11. A grinding machine, comprising a frame and a transmission device, wherein the transmission device is mounted on the frame; characterized in that: Also includes: A grinding cylinder, wherein the grinding cylinder and the transmission device are directly or indirectly mounted on the frame; The grinding cylinder comprises: A housing, the housing comprising: a liquid inlet, which is a through hole penetrating the inner surface and the outer surface of the shell; The liquid outlet is a through hole penetrating the inner and outer surfaces of the shell; the liquid inlet and the liquid outlet are spaced apart; Middle shell; An inner shell, the middle shell and the inner shell are fixedly connected; The outer shell, the middle shell and the inner shell are arranged in sequence from the outside to the inside; A convex ridge is arranged between the middle shell and the outer shell, and a height of the convex ridge is smaller than a distance between an outer surface of the middle shell and an inner surface of the outer shell.

12. A method for manufacturing a grinding cylinder, characterized in that: include: The middle shell is subjected to a heating treatment; The heating temperature is greater than or equal to 200 degrees Celsius, and the heating time is greater than or equal to 30 minutes; placing an inner shell into the middle shell; Air-cooling the inner shell and the middle shell for at least 90 minutes; Sleeve the outer shell onto the outer surface of the middle shell; The middle shell and the outer shell are tightly matched to form the grinding cylinder; Wherein, the housing comprises: a liquid inlet, which is a through hole penetrating the inner surface and the outer surface of the shell; The liquid outlet is a through hole penetrating the inner and outer surfaces of the shell; the liquid inlet and the liquid outlet are spaced apart; The middle shell and the inner shell are fixedly connected; The outer shell, the middle shell and the inner shell are arranged in sequence from the outside to the inside; A convex ridge is arranged between the middle shell and the outer shell, and a height of the convex ridge is smaller than a distance between an outer surface of the middle shell and an inner surface of the outer shell.

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