Roller manufacturing process for calender, auxiliary roller and transition roller

Abstract

The invention discloses a roller manufacturing process for a calender, an auxiliary roller and a transition roller. The process comprises the steps of raw material pouring, round bar forging, machining, sand blasting texturing, priming coat spraying, surface layer spraying, grinding, polishing and the like. According to the process, a layer of specific metal material is sprayed on the surface of the roller blank to serve as a bottom layer, a layer of ceramic material surface layer is sprayed on the surface of the roller blank, the main component of the surface layer coating is an A < l > 2O3 and T O2 mixture prepared according to a certain proportion, the thickness of the surface layer coating is controlled to be about 400 microns, the coating has good bonding performance on the metal material, the bonding strength of the coating is larger than 30 MPa, and the service life of the coating is prolonged. The coating has the advantages that the coating does not fall off during use, the Vickers hardness of a roller coated with the coating can reach 700-1000 in the aspect of strength improvement and is about doubled compared with the original hardness, and meanwhile, the temperature resistance of the roller can be improved to 600-800 DEG C after the roller is coated with the coating.

Description

Technical Field

[0001] The invention relates to the technical field of equipment for glass production, and in particular to a manufacturing process of rollers for a calender, an auxiliary roller and a transition roller. Background Art

[0002] The calender is a key equipment for calendering glass. Its forming principle is to heat the glass to a molten state, so that the glass is in a colloidal state and has a certain plasticity. After the colloidal glass is pressed by the upper and lower calendering rollers into a glass ribbon with a certain width, the glass ribbon is further stretched by the auxiliary roller group and the transition roller group at gradually increased speed to make the thickness of the glass ribbon meet the requirements. During the forming process, the rollers of the auxiliary roller group and the transition roller group need to withstand a certain radial force, and the material of the rollers needs to have a certain rigidity. The thermal bending resistance requirements are high under high temperature conditions. The physical properties of the rollers mainly affect the following aspects:

[0003] If the rollers are not rigid enough, the rollers may bend, which may cause the glass ribbon to form transverse lines after cooling and forming, thus affecting the final quality of the glass sheet.

[0004] The heat conduction speed of the roller is too fast, the roller dissipates heat, and the temperature is too low, which will cause the glass ribbon to cool too quickly, forming cold cracks. The subsequent tempering will cause cracks and affect the yield rate.

[0005] The uneven thickness of the roller wall leads to uneven temperature of the entire roller surface, large thickness difference of the glass ribbon, and the force of the roller is concentrated on the thin wall, which aggravates the wear and even causes breakage.

[0006] The existing roller body is generally made of Cr-containing alloy materials such as 1Cr17Ni2, 2Cr13 and 1Cr13. This material belongs to martensitic stainless steel. The Cr element can improve the corrosion resistance, hardness and strength of the metal, but the characteristics of metal materials are poor thermal deformation resistance and high thermal conductivity. The metal begins to deform at 500℃, and the deformation will increase further as the temperature rises. The temperature of the glass ribbon in this area is generally above 650℃, followed by thermal conductivity. In order to control the temperature within a certain range, the rollers of the auxiliary roller group and the transition roller group are hollow cavities and circulate cooling water. The temperature in this area is dynamically stabilized by adjusting the cooling water volume. Due to the high thermal conductivity of the metal and fast heat dissipation, the cooling speed of the glass ribbon is still too fast and shows an uneven distribution trend even under low water volume. At the same time, metal rollers will also suffer from rust erosion and other phenomena when stored for a long time, which is not conducive to the storage of rollers. Summary of the invention

[0007] The purpose of the present invention is to provide a manufacturing process for rollers, auxiliary rollers and transition rollers for calenders, aiming to solve at least one of the technical problems existing in the above-mentioned prior art. To achieve the above-mentioned purpose, the technical solutions adopted by the present invention are as follows:

[0008] A calender roller manufacturing process comprises the following steps:

[0009] S1, raw material pouring: pour the metal slurry into a customized mold, vibrate and cool it to form a blank of the desired shape;

[0010] S2, round bar forging: Based on the cast blank, the blank is forged repeatedly and continuously through large-scale forging equipment to gradually deform it into a cylindrical roller blank;

[0011] S3, machining: Use precision machine tools to machine the outer dimensions and surface quality of the roller blank to within the sprayable range, preparing for the subsequent spraying process;

[0012] S4, sandblasting: sandblasting the surface of the roll blank to remove oxides and impurities on the surface of the roll blank, and at the same time make the surface of the roll blank have a certain degree of roughness to increase the bonding force between the spray layer and the roll blank;

[0013] S5, spraying primer: spraying a layer of specific metal material as primer on the surface of the roller blank after sandblasting;

[0014] S6, spraying surface layer: spraying ceramic surface coating on the base layer;

[0015] S7, grinding and polishing: grinding and polishing the roller surface after spraying to remove surface defects and uneven parts.

[0016] As a further solution of the present invention: step S6 comprises:

[0017] S61, fixing the workpiece processed in step S5 on the spraying equipment, setting the workpiece rotation speed, and adjusting the muzzle of the spraying gun to a suitable position;

[0018] S62, loading the preheated powder into the powder feeder;

[0019] S63, start the air compressor and exhaust dust removal system, start the water pump, adjust the Ar, H2, and N2 pressures, and turn on Ar, H2, and N2 to a stable flow rate;

[0020] S64, ignite the spray gun to spray, adjust the voltage and current values, and start the powder feeder;

[0021] S65, set the spray gun horizontal movement speed to 6mm / min, spray the workpiece back and forth, the number of back and forth times is determined by the thickness of the surface layer, and during the spraying process, confirm that there is no flame failure;

[0022] S66, after spraying, wait for the workpiece to cool to room temperature, measure the workpiece size, and confirm that the surface spray thickness meets the required requirements.

[0023] As a further solution of the present invention: in step S61 s, adjusting the muzzle of the spray gun to a suitable position includes: adjusting the muzzle of the spray gun and the center of the workpiece to be on the same horizontal plane, and adjusting the distance from the muzzle to the workpiece to be 90-125 mm.

[0024] As a further solution of the present invention: in step S65, during the spraying process, the gun needs to be stopped and checked once or twice to confirm that there are no unmelted particles or impurities on the coating surface. If there are any, they need to be removed with a small file before continuing spraying.

[0025] As a further solution of the present invention: in step S3, the outer dimensions and surface quality of the roller blank are processed to within the sprayable range: according to the size requirements of the drawing, the outer dimensions of the roller blank are the final finished product dimensions minus the undercut dimensions reserved for the coating, with a tolerance of ±5 wires.

[0026] As a further solution of the present invention: in step S4, the sandblasting pressure during the sandblasting process is 0.4 MPa, and the roughness of the roller surface after sandblasting is Ra9-Ra13.

[0027] As a further solution of the present invention: in step S5, the thickness of the base layer sprayed on the surface of the roller blank is 0.1-0.15 mm.

[0028] The present invention also provides an auxiliary roller for a calender, comprising a roller prepared according to any of the above-mentioned calender roller manufacturing processes, wherein the surface layer of the roller is a mixture of 3% TiO2 and 97% Al2O3, and the surface layer thickness is 400um.

[0029] And, a transition roller for a calender, comprising a roller prepared according to any of the above-mentioned calender roller manufacturing processes, wherein the surface layer composition of the roller is a mixture of 3% TiO2 and 97% Al2O3, and the surface layer thickness is 400um.

[0030] Beneficial effects of the present invention:

[0031] The present invention sprays a layer of specific metal material as a base layer and a layer of ceramic material as a surface layer on the surface of the roller blank. The main component of the surface layer coating is a mixture of Al2O3 and TiO2 in a certain proportion. The thickness of the surface layer coating is controlled to be about 400um. If the coating is too thin, it will cause wear failure, and if it is too thick, it will reduce the cooling performance and increase the cost. The coating has good bonding performance for the metal material, and its bonding strength is greater than 30MPa. It will not fall off during use. In terms of strength improvement, the Vickers hardness of the roller after coating can reach 700-1000, which is about twice the original hardness. At the same time, after coating, the temperature resistance of the roller can be improved to 600-800℃. Within this temperature, the deformation of the roller is small, which can meet the process production requirements. During long-term storage, there will be no rust erosion and other phenomena, which is beneficial to the storage of the roller. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be further described below in conjunction with the accompanying drawings.

[0033] Figure 1 It is a schematic diagram of a manufacturing process flow of a roller for a calender according to the present invention;

[0034] Figure 2 It is a schematic diagram of the process steps of spraying the surface layer of the present invention;

[0035] Figure 3 It is a partial cross-sectional schematic diagram of the roller structure of the present invention. DETAILED DESCRIPTION

[0036] 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.

[0037] See also Figure 1 As shown, the first embodiment of the present invention provides a process for manufacturing a roller for a calender, comprising the following steps:

[0038] Step 1: Pouring of raw materials

[0039] The metal slurry is poured into a custom mold, vibrated and cooled to form a blank of the desired shape.

[0040] Mold preparation: Mold making is a key step in the casting process, which determines the shape and size of the final blank. The mold is usually made of high-strength materials such as alloys or specially treated molding sand. When making the mold, it is necessary to ensure the accuracy and details of the mold to avoid shape deviations in the cast blank.

[0041] Metal slurry smelting: After the required elements (the main chemical components are Cr, C, Si, Mn, P, S) are mixed according to the proportion, they need to be heated to a molten state. This process is usually carried out in a furnace, and the temperature of the furnace needs to be precisely controlled to ensure that the metal can be completely melted and will not be burned due to excessive temperature. During the smelting process, alloy elements can also be added as needed to improve the properties of the metal. This process requires precise control of the chemical composition percentage of the material, and the performance of the metal material must be tested by penetrant testing and water pressure testing to ensure that the performance of the metal material meets the standards.

[0042] Pouring and cooling: After the molten metal slurry is poured into the mold, it needs to be vibrated to remove bubbles and evenly distribute the metal slurry. Then, the metal is cooled and solidified in the mold. The cooling process needs to control the cooling rate to avoid deformation or cracks caused by uneven cooling, forming a blank of the desired shape.

[0043] Step 2: Round bar forging

[0044] Based on the cast blank, the blank is forged repeatedly through large forging equipment to gradually deform it into a cylindrical roller blank. This process requires exquisite skills and rich experience to ensure the size and shape accuracy of the roller blank.

[0045] Before forging, the blank usually needs to be heated to reduce its deformation resistance and improve plasticity. The heating temperature needs to be controlled within a certain range to avoid overheating or overburning.

[0046] During the forging process, the forging force and frequency need to be controlled to ensure the size and shape accuracy of the roll blank.

[0047] Post-forging treatment: After forging, the roller blank needs to be subjected to heat treatment such as annealing or quenching to eliminate the internal stress generated during the forging process and optimize the microstructure.

[0048] Based on the cast blank, the blank is forged repeatedly and continuously by large-scale forging equipment, so that it is gradually deformed into a cylindrical roller blank;

[0049] Step 3: Machining

[0050] Use precision machine tools to process the outer dimensions and surface quality of the roller blank to within the sprayable range, preparing for the subsequent spraying process.

[0051] Design and planning: Before machining, it is necessary to design and plan the product according to the size and shape requirements of the roll blank, which includes determining the processing technology, drawing a processing flow chart, etc.

[0052] Processing preparation: Cut the roll blank into appropriate size and fix it with a clamp. The selection and use of the clamp must ensure the accuracy and safety of the processing.

[0053] Processing operation and inspection: According to the processing flow chart, turning, milling, grinding and other processing operations are carried out. During the processing, the processed products need to be constantly inspected and corrected to ensure that the product size and quality meet the requirements.

[0054] According to the size requirements of the drawing, the general size is the final finished product size requirement minus the undercut size reserved for coating, with a tolerance of ±5 wires.

[0055] Step 4: Sandblasting

[0056] In order to improve the adhesion and wear resistance of the spray layer, the surface of the roller blank needs to be sandblasted. During the sandblasting process, the high-speed sprayed sand particles can remove the oxides and impurities on the surface of the roller blank, and at the same time make the surface rough, thereby increasing the bonding force between the spray layer and the roller blank. The sandblasting pressure during the sandblasting process is 0.4MPa, and the roughness of the roller blank surface after sandblasting is Ra9-Ra13.

[0057] Pretreatment: Before sandblasting, the surface of the roller blank needs to be pretreated, such as removing oil stains, oxide layers, etc. This helps to improve the sandblasting effect and the bonding strength between the spray layer and the roller blank.

[0058] Sandblasting parameters: According to the material of the roller blank and the sandblasting requirements, adjust the parameters of the sandblasting machine such as the spraying pressure, sand type, and sandblasting time.

[0059] Post-blasting treatment: After sandblasting, the roller blank needs to be cleaned to remove residual sand and dust.

[0060] Step 5: Spray the base layer

[0061] After sandblasting, a layer of specific metal material is sprayed on the surface of the roller blank as a primer. This step is to improve the protective performance and stability of the spray layer and prevent oxidation and corrosion of the underlying metal. The material selection and thickness control of the primer are key, which will affect the life and performance of the entire spray layer. The primer material can be a high-temperature resistant metal alloy, such as nickel-chromium alloy. The thickness of the primer sprayed on the surface of the roller blank is 0.1-0.15mm.

[0062] Step 6: Spray the surface layer

[0063] On the basis of the base layer, spray the ceramic surface coating.

[0064] See also Figure 2 As shown, spraying the surface layer specifically includes the following steps:

[0065] Use atmospheric plasma spray equipment to:

[0066] Fix the workpiece processed in step S5 with three claws and a center, set the workpiece speed, adjust the muzzle and the center of the workpiece to be on the same level, and adjust the distance between the muzzle and the workpiece to 90-125mm.

[0067] The powder feeder is loaded with preheated powder.

[0068] Turn on the air compressor and exhaust dust removal system, turn on the water pump, adjust the Ar, H2, and N2 pressures, and turn on Ar, H2, and N2 to a stable flow rate.

[0069] Ignite the gun for spraying, adjust the voltage and current values, and start the powder feeder.

[0070] Ignite the spray gun and set the spray gun to move horizontally at a speed of 6mm / min. Spray the workpiece back and forth. The number of back and forth movements is determined by the coating thickness. The coating thickness plus the amount of grinding is generally between 0.3mm and 0.4mm. During the spraying process, make sure there is no flame failure.

[0071] During the spraying process, the gun needs to be stopped and checked once or twice to confirm that there are no unmelted particles or impurities on the coating surface. If there are any, they need to be removed with a small file before continuing spraying.

[0072] After spraying, wait for the workpiece to cool to room temperature, measure the workpiece size, and confirm that the coating thickness meets the required requirements.

[0073] Step 7: Grinding and Polishing

[0074] After spraying, the roller surface needs to be machined for the last time, mainly grinding and polishing. Through these processes, the roughness of the roller surface meets the requirements and the quality and performance of the sprayed layer are ensured.

[0075] It should be noted that in the entire process, the quality of each link needs to be strictly controlled to ensure that the performance and quality of the final product meet the requirements. Equipment and tools need to be regularly maintained and serviced to extend their service life and improve production efficiency. During the operation, safe operating procedures need to be followed to ensure the safety of operators.

[0076] See also Figure 3 As shown, the second embodiment of the present invention provides an auxiliary roller for a calender, including a roller prepared by a calender roller manufacturing process according to the first embodiment, the surface layer composition of the roller is a mixture of 3% TiO2 and 97% Al2O3, and the surface layer thickness is 400um.

[0077] See also Figure 3As shown, the third embodiment of the present invention provides a transition roller for a calender, comprising a roller prepared according to any of the above-mentioned calender roller manufacturing processes, wherein the surface layer composition of the roller is a mixture of 3% TiO2 and 97% Al2O3, and the surface layer thickness is 400um.

[0078] The present invention sprays a ceramic coating or other functional strengthening coating with similar effects on the surface of the roller body. The main component of the coating is a mixture of Al2O3 and TiO2 in a certain proportion. The coating thickness is controlled at about 400um. If the coating is too thin, it will cause wear failure, and if it is too thick, it will reduce the cooling performance and increase the cost. The coating has good bonding performance for metal materials, and its bonding strength is greater than 30MPa. It will not fall off during use. In terms of strength improvement, the Vickers hardness of the roller after coating can reach 700-1000, which is about twice the original hardness. At the same time, after coating, the temperature resistance of the roller can be improved to 600-800℃. Within this temperature, the deformation of the roller is small, which can meet the process production requirements.

[0079] The above is a detailed description of the preferred embodiments of the present invention, which cannot be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A process for manufacturing a roller for a calender, characterized in that: The following steps are involved: S1, raw material pouring: pour the metal slurry into a customized mold, vibrate and cool it to form a blank of the desired shape; S2, round bar forging: Based on the cast blank, the blank is forged repeatedly and continuously through large-scale forging equipment to gradually deform it into a cylindrical roller blank; S3, machining: Use precision machine tools to machine the outer dimensions and surface quality of the roller blank to within the sprayable range, preparing for the subsequent spraying process; S4, sandblasting: sandblasting the surface of the roll blank to remove oxides and impurities on the surface of the roll blank, and at the same time make the surface of the roll blank have a certain degree of roughness to increase the bonding force between the spray layer and the roll blank; S5, spraying primer: spraying a layer of specific metal material as primer on the surface of the roller blank after sandblasting; S6, spraying surface layer: spraying ceramic surface coating on the base layer; S7, grinding and polishing: grinding and polishing the roller surface after spraying to remove surface defects and uneven parts.

2. A process for manufacturing a roller for a calender according to claim 1, characterized in that: Step S6 includes: S61, fixing the workpiece processed in step S5 on the spraying equipment, setting the workpiece rotation speed, and adjusting the muzzle of the spraying gun to a suitable position; S62, loading the preheated powder into the powder feeder; S63, start the air compressor and exhaust dust removal system, start the water pump, adjust the Ar, H2, and N2 pressures, and turn on Ar, H2, and N2 to a stable flow rate; S64, ignite the spray gun to spray, adjust the voltage and current values, and start the powder feeder; S65, set the spray gun horizontal movement speed to 6mm / min, spray the workpiece back and forth, the number of back and forth times is determined by the thickness of the surface layer, and during the spraying process, confirm that there is no flame failure; S66, after spraying, wait for the workpiece to cool to room temperature, measure the workpiece size, and confirm that the surface spray thickness meets the required requirements.

3. A process for manufacturing a roller for a calender according to claim 2, characterized in that: In step S61, adjusting the muzzle of the spray gun to a suitable position includes: adjusting the muzzle of the spray gun and the center of the workpiece to be on the same horizontal plane, and adjusting the distance between the muzzle and the workpiece to be 90-125 mm.

4. A process for manufacturing a roller for a calender according to claim 3, characterized in that: In step S65, the spraying process needs to be stopped and checked once or twice to confirm that there are no unmelted particles or impurities on the coating surface. If there are any, they need to be removed with a small file before continuing spraying.

5. A process for manufacturing a roller for a calender according to claim 4, characterized in that: In step S66, the surface layer spraying thickness is 0.3mm-0.4mm.

6. The manufacturing process of a roller for a calender according to claim 1, characterized in that: In step S3, the outer dimensions and surface quality of the roller blank are processed to be within the sprayable range as follows: according to the size requirements of the drawing, the outer dimensions of the roller blank are the final finished product dimensions minus the undercut dimensions reserved for the coating, with a tolerance of ±5 wires.

7. The manufacturing process of a roller for a calender according to claim 1, characterized in that: In step S4, the sandblasting pressure during the sandblasting process is 0.4 MPa, and the roughness of the roller surface after sandblasting is Ra9-Ra13.

8. The manufacturing process of a roller for a calender according to claim 1, characterized in that: In step S5, the thickness of the base layer sprayed on the surface of the roller blank is 0.1 mm-0.15 mm.

9. An auxiliary roller for a calender, characterized in that: It comprises a roller prepared by a roller manufacturing process for a calender according to any one of claims 1 to 8, wherein the surface layer composition of the roller is a mixture of 3% TiO2 and 97% Al2O3, and the surface layer thickness is 400um.

10. A transition roller for a calender, characterized in that: A roller prepared by a roller manufacturing process for a calender according to any one of claims 1 to 8, wherein the surface layer of the roller is composed of 3% TiO 2和 A mixture of 97% Al2O3, the surface layer thickness is 400um.

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