CN113752093A - Silicon carbide grinding and polishing method - Google Patents
Silicon carbide grinding and polishing method Download PDFInfo
- Publication number
- CN113752093A CN113752093A CN202010503235.8A CN202010503235A CN113752093A CN 113752093 A CN113752093 A CN 113752093A CN 202010503235 A CN202010503235 A CN 202010503235A CN 113752093 A CN113752093 A CN 113752093A
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- grinding
- silicon carbide
- placing
- disc
- fine
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/11—Lapping tools
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/27—Work carriers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/34—Accessories
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B57/00—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents
- B24B57/02—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention discloses a silicon carbide grinding and polishing method which comprises the steps of rough grinding, fine grinding, polishing and the like of silicon carbide, wherein the grinding machine is a plane grinding machine, the tooth pitch of a rough grinding disc is 5mm, and the tooth pitch of a fine grinding disc is 3.2 mm. Each step of grinding and polishing is matched with a proper balancing weight, grinding speed, grinding time and grinding liquid, and finally a high-quality grinding end face can be obtained.
Description
Technical Field
The invention relates to a silicon carbide grinding and polishing method.
Background
The mechanical seal is a shaft seal device of rotary machinery, and is widely applied to equipment such as pumps, reaction kettles, compressors and the like. The schematic diagram of a typical mechanical sealing structure is shown in fig. 1, and the typical mechanical sealing structure mainly comprises a cavity 1, a spring seat 2, a spring 3, a moving ring sealing ring 4, a moving ring 5, a static ring sealing ring 6, a static ring 7, an anti-rotation pin 8, a gland 9, a gland sealing ring 10, a transmission pin 11 and the like. While mechanical seals typically have 4 leak points: the joint 101 of the gland 9 and the cavity 1, the joint 102 of the stationary ring 7 and the gland 9, the joint 104 of the movable ring 5 and the shaft and the gap 103 of the contact end surface between the sealing rings. The joints 101, 102 and 104 of the first 3 leakage points can effectively prevent the leakage of the medium by arranging a sealing ring or a sealing gasket; for the gap 103 at the sealing end face between the moving ring 5 and the static ring 7, because the moving ring 5 and the static ring 7 slide relatively, the sealing cannot be realized by a sealing ring or a sealing gasket, the leakage amount mainly depends on the grinding precision of the sealing end face, and the normal use requirement of mechanical sealing can be met only when the flatness tolerance of the sealing end face is not more than 0.9 μm and the surface roughness Ra is not more than 0.2 μm.
Silicon carbide is used as a common moving ring material or a common static ring material, the grinding process is complex, and the common grinding method cannot enable the end face of the silicon carbide to reach qualified grinding precision.
Disclosure of Invention
The invention provides a silicon carbide grinding and polishing method, aiming at solving the defect of insufficient grinding precision of a common silicon carbide grinding method.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a silicon carbide grinding and polishing method comprises the following steps:
(1) cleaning silicon carbide, a rough grinding disc and a planet ring, placing the planet ring on the rough grinding disc, and setting the rotating speed of the rough grinding disc to be 35-40 r/min;
(2) placing the silicon carbide in the planet ring lightly, and placing the grinding end face of the silicon carbide close to the rough grinding disc;
(3) placing a rough grinding balancing weight on the silicon carbide, and adding rough grinding liquid;
(4) starting a grinding machine to perform coarse grinding, wherein the grinding time is 15-20 min, and adding the coarse grinding fluid every 5min in the grinding process;
(5) stopping the grinding machine, and taking out the rough grinding balancing weight, the silicon carbide and the planet ring;
(6) cleaning silicon carbide, a fine grinding disc and a planet ring, placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 20-30 r/min;
(7) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(8) placing a fine grinding balancing weight on the silicon carbide, and adding fine grinding liquid;
(9) starting a grinding machine, carrying out fine grinding for 20-25 min, and adding fine grinding liquid every 5min in the grinding process;
(10) stopping the grinding machine, and taking out the fine grinding balancing weight, the silicon carbide and the planet ring;
(11) cleaning silicon carbide, a fine grinding disc and a planet ring, placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 15-25 r/min;
(12) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(13) placing a polishing balancing weight on the silicon carbide, and adding polishing liquid;
(14) starting a grinding machine to polish for 20-25 min, and adding the polishing solution every 5min in the grinding process;
(15) stopping the grinding machine, and taking out the polishing balancing weight and the silicon carbide;
(16) and carrying out ultrasonic cleaning on the surface of the silicon carbide.
Preferably, the grinder described in steps (4), (5), (9), (10), (14) and (15) is a flat grinder.
Preferably, the rough grinding disc in the steps (1) and (2) is made of nodular cast iron alloy containing copper and molybdenum, and the distance between teeth on the rough grinding disc is 5 mm.
Preferably, the material of the finish grinding disc in the steps (6), (7), (11) and (12) is nodular cast iron alloy containing copper and molybdenum, and the pitch of the teeth on the finish grinding disc is 3.2 mm.
Preferably, the weight of the rough grinding balancing weight in the steps (3) and (5) is that the contact pressure between the end face of the silicon carbide and the grinding disc reaches 10-20N/cm2。
Preferably, the coarse grinding fluid in the steps (3) and (4) is prepared by mixing 50L of distilled water and 220g of diamond grinding paste with the particle size of 5-7 μm.
Preferably, the weight of the fine grinding balancing weight in the steps (8) and (10) is that the contact pressure between the end face of the silicon carbide and the grinding disc reaches 1-5N/cm2。
Preferably, the fine grinding fluid in the steps (8) and (9) is prepared by mixing 50L of distilled water and 400g of diamond grinding paste with the particle size of 2.5-3.5 μm.
Preferably, the weight of the polishing balance weight block in the steps (13) and (15) is such that the contact pressure between the end face of the silicon carbide and the grinding disc is 1-3N/cm2。
Preferably, the polishing solution in steps (13) and (14) is prepared by mixing 1.5L of distilled water and 20g of diamond grinding paste with the particle size of 1.0-1.5 μm.
The invention achieves the following beneficial effects: the silicon carbide grinding method has low cost and simple operation, and can obtain high-quality ground end faces.
Drawings
Fig. 1 is a schematic view of a typical mechanical seal.
FIG. 2 is a schematic view of the structure of the polishing disk.
Detailed Description
The invention is further described below with reference to specific examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
A silicon carbide grinding and polishing method comprises the following steps:
(1) cleaning silicon carbide, a rough grinding disc and a planet ring by using ultrasonic waves, then placing the planet ring on the rough grinding disc, and setting the rotating speed of the rough grinding disc to be 40 r/min;
(2) placing the silicon carbide in the planet ring lightly, and placing the grinding end face of the silicon carbide close to the rough grinding disc;
(3) placing a rough grinding balancing weight on the silicon carbide, and adding 200ml of rough grinding liquid;
(4) starting a grinder to perform coarse grinding, wherein the grinding time is 20min, and 200ml of coarse grinding fluid is added once respectively at 5min, 10min and 15min after the grinding is started;
(5) stopping the grinding machine, and taking out the rough grinding balancing weight, the silicon carbide and the planet ring;
(6) cleaning silicon carbide, a fine grinding disc and a planet ring by using ultrasonic waves, then placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 25 r/min;
(7) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(8) placing a fine grinding balancing weight on the silicon carbide, and adding 200ml of fine grinding liquid;
(9) starting a grinder to perform fine grinding, wherein the grinding time is 25min, and 200ml of fine grinding fluid is added once respectively at 5min, 10min, 15min and 20min after the grinding is started;
(10) stopping the grinding machine, and taking out the fine grinding balancing weight, the silicon carbide and the planet ring;
(11) cleaning silicon carbide, a fine grinding disc and a planet ring by using ultrasonic waves, then placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 20 r/min;
(12) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(13) placing a polishing balancing weight on the silicon carbide, and adding 200ml of polishing solution;
(14) starting the grinding machine to polish for 25min, and adding 200ml of polishing solution once every 5min, 10min, 15min and 20min after the grinding is started;
(15) stopping the grinding machine, and taking out the polishing balancing weight and the silicon carbide;
(16) and (4) carrying out ultrasonic cleaning on the surface of the silicon carbide by using oxalic acid mixed liquor.
Specifically, the grinding machine described in steps (4), (5), (9), (10), (14) and (15) is a plane grinding machine, the structural schematic diagram of the grinding disc on the grinding machine is shown in fig. 2, the grinding disc 201 rotates counterclockwise, the grinding disc 201 and the clamp 203 on the grinding machine drive 202 the planet ring to rotate, and the silicon carbide and the counterweight 204 are placed in the planet ring 202.
Specifically, the rough grinding disc in the steps (1) and (2) is made of copper-molybdenum-containing alloy nodular cast iron, and the distance between teeth on the rough grinding disc is 5 mm.
Specifically, the material of the finish grinding disc in the steps (6), (7), (11) and (12) is copper-molybdenum-containing alloy nodular cast iron, and the pitch of the teeth on the finish grinding disc is 3.2 mm.
Specifically, the weight of the rough grinding balancing weight in the steps (3) and (5) enables the contact pressure between the end face of the silicon carbide and the grinding disc to reach 15N/cm2。
Specifically, the crude polishing slurry described in steps (3) and (4) was prepared by mixing 50L of distilled water and 220g of diamond paste having a particle size of 7 μm.
Specifically, the weight of the fine grinding balancing weight in the steps (8) and (10) is adjusted to ensure that the contact pressure between the end face of the silicon carbide and the grinding disc reaches 4N/cm2。
Specifically, the fine polishing slurry described in steps (8) and (9) was prepared by mixing 50L of distilled water and 400g of diamond paste having a particle size of 3.5 μm.
Specifically, the weight of the polishing balance weight block in the steps (13) and (15) is adjusted to make the contact pressure between the end face of the silicon carbide and the grinding disc reach 2N/cm2。
Specifically, the polishing slurry described in steps (13) and (14) was prepared by mixing 1.5L of distilled water and 20g of diamond paste having a particle size of 1.5 μm.
Claims (10)
1. A silicon carbide grinding and polishing method is characterized by comprising the following steps:
(1) cleaning silicon carbide, a rough grinding disc and a planet ring, placing the planet ring on the rough grinding disc, and setting the rotating speed of the rough grinding disc to be 35-40 r/min;
(2) placing the silicon carbide in the planet ring lightly, and placing the grinding end face of the silicon carbide close to the rough grinding disc;
(3) placing a rough grinding balancing weight on the silicon carbide, and adding rough grinding liquid;
(4) starting a grinding machine to perform coarse grinding, wherein the grinding time is 15-20 min, and adding the coarse grinding fluid every 5min in the grinding process;
(5) stopping the grinding machine, and taking out the rough grinding balancing weight, the silicon carbide and the planet ring;
(6) cleaning silicon carbide, a fine grinding disc and a planet ring, placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 20-30 r/min;
(7) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(8) placing a fine grinding balancing weight on the silicon carbide, and adding fine grinding liquid;
(9) starting a grinding machine, carrying out fine grinding for 20-25 min, and adding fine grinding liquid every 5min in the grinding process;
(10) stopping the grinding machine, and taking out the fine grinding balancing weight, the silicon carbide and the planet ring;
(11) cleaning silicon carbide, a fine grinding disc and a planet ring, placing the planet ring on the fine grinding disc, and setting the rotating speed of the fine grinding disc to be 15-25 r/min;
(12) lightly placing the silicon carbide in the planet ring, and placing the grinding end face of the silicon carbide close to the fine grinding disc;
(13) placing a polishing balancing weight on the silicon carbide, and adding polishing liquid;
(14) starting a grinding machine to polish for 20-25 min, and adding the polishing solution every 5min in the grinding process;
(15) stopping the grinding machine, and taking out the polishing balancing weight and the silicon carbide;
(16) and carrying out ultrasonic cleaning on the surface of the silicon carbide.
2. The silicon carbide grinding and polishing method according to claim 1, wherein the grinder in steps (4), (5), (9), (10), (14) and (15) is a flat grinder.
3. The silicon carbide grinding and polishing method as claimed in claim 1, wherein the rough grinding disc in steps (1) and (2) is made of nodular cast iron alloy containing copper and molybdenum, and the pitch of teeth on the rough grinding disc is 5 mm.
4. The silicon carbide grinding and polishing method according to claim 1, wherein the material of the finish grinding disc in steps (6), (7), (11) and (12) is nodular cast iron alloy containing copper and molybdenum, and the pitch of the teeth on the finish grinding disc is 3.2 mm.
5. The silicon carbide grinding and polishing method according to claim 1, wherein the weight of the rough grinding weight in steps (3) and (5) is such that the contact pressure between the end face of the silicon carbide and the grinding disc is 10 to 20N/cm2。
6. The method according to claim 1, wherein the coarse grinding liquid in steps (3) and (4) is prepared by mixing 50L of distilled water and 220g of diamond grinding paste with a particle size of 5-7 μm.
7. The method of claim 1, wherein the weight of the fine grinding weight in steps (8) and (10) is such that the contact pressure between the end face of the silicon carbide and the grinding plate is 1-5N/cm2。
8. The method according to claim 1, wherein the fine grinding fluid in steps (8) and (9) is a mixture of 50L of distilled water and 400g of diamond grinding paste having a particle size of 2.5 to 3.5 μm.
9. The silicon carbide grinding and polishing method as claimed in claim 1, wherein the step (1)3) The weight of the polishing weight member in (1) and (15) is such that the contact pressure between the end face of the silicon carbide and the abrasive disk is 1 to 3N/cm2。
10. The method according to claim 1, wherein the polishing solution in steps (13) and (14) is a mixture of 1.5L of distilled water and 20g of diamond paste having a particle size of 1.0 to 1.5 μm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010503235.8A CN113752093A (en) | 2020-06-05 | 2020-06-05 | Silicon carbide grinding and polishing method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010503235.8A CN113752093A (en) | 2020-06-05 | 2020-06-05 | Silicon carbide grinding and polishing method |
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| CN113752093A true CN113752093A (en) | 2021-12-07 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114932500B (en) * | 2022-06-24 | 2023-08-04 | 南京航空航天大学 | Grinding and polishing integrated device and operation method thereof |
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| CN114932500B (en) * | 2022-06-24 | 2023-08-04 | 南京航空航天大学 | Grinding and polishing integrated device and operation method thereof |
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