Vacuum-pumping sealing device for rotary drying of high-purity quartz and vacuum drying machine

Abstract

The vacuum-pumping sealing device comprises an inner barrel, a driving shaft and a vacuum tube, the inner barrel and the driving shaft are fixedly connected and are both in running fit with the vacuum tube, a third sealing piece is arranged between running fit surfaces of the driving shaft and the vacuum tube, and the third sealing piece is fixedly connected with the driving shaft. The third sealing piece comprises a filling groove formed in the matching face and a sealing gland, the filling groove is filled with padding, the sealing gland and the driving shaft are detachably fixed, and the filling groove can form a closed cavity structure through the sealing gland. According to the utility model, the third sealing element is arranged between the driving shaft and the running fit surface of the vacuum tube, so that when the filler is abraded within a certain range in a filler sealing manner, the sealing device can be continuously used by adjusting the compression amount of the sealing gland. The replacement period of the sealing piece is shortened, the sealing effect is guaranteed, and meanwhile the service life of the sealing piece is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum drying equipment, and more specifically to a vacuum sealing device and a vacuum dryer for rotary drying of high-purity quartz. Background Art

[0002] In the production and processing of high-purity quartz sand, after undergoing processes such as crushing, screening, flotation, purification, and dehydration, the sand still requires a further drying step before packaging. A commonly used drying equipment for granular or powdered materials is the double-cone rotary vacuum dryer. This works by evacuating the material cavity within the cone. Heat energy is then transferred through the double-cone jacket, and the rotating double-cone rotates the material, drying it. Simultaneously, moisture in the material is converted to water vapor through the vacuum line and removed from the double-cone cavity. The vacuum line seals typically utilize O-rings or lip seals. However, due to the high purity requirements and the abrasive nature of the particles, existing vacuum seals for high-purity quartz sand drying processes have a short service life, are prone to material spillage on the sealing surface, and, when the seal wears, can easily draw rust into the cavity, contaminating the material. Utility Model Content

[0003] The technical problem to be solved by the present invention is how to reduce the replacement cost of the sealing element.

[0004] The utility model solves the above-mentioned technical problems through the following technical means: a vacuum sealing device for rotary drying of high-purity quartz, comprising an inner cylinder, a driving shaft, and a vacuum tube, wherein the inner cylinder is fixedly connected to the driving shaft and both are rotatably matched with the vacuum tube, a third sealing member is provided between the rotating matching surfaces of the driving shaft and the vacuum tube, the third sealing member comprises a filling groove and a sealing gland opened in the matching surface, the filling groove is filled with filler, the sealing gland is detachably fixed to the driving shaft, and can cause the filling groove to form a closed cavity structure.

[0005] By providing a third seal between the driving shaft and the rotating mating surface of the vacuum tube, when the packing is worn within a certain range through the packing seal, the packing can be continued to be used by adjusting the compression amount of the sealing cover, thereby reducing the replacement cycle of the seal, ensuring the sealing effect and improving the service life of the seal.

[0006] As a preferred technical solution, a first seal is provided between the rotating mating surface of the inner cylinder and the vacuum tube. The first seal includes a sealing shell, a support bearing, and a lip-shaped sealing ring. The sealing shell is provided with a closed first cavity structure. The support bearing and the lip-shaped sealing ring are both arranged in the first cavity structure. The outer ring of the support bearing is fixed to the inner cylinder through the sealing shell, and the inner ring of the support bearing is fixed to the vacuum tube.

[0007] As a preferred technical solution, the inner cylinder is fixedly connected to the driving shaft, and an O-ring is provided at the connecting surface between the inner cylinder and the driving shaft.

[0008] As a preferred technical solution, the sealing shell includes a left connecting part and a right connecting part, and the left connecting part and the right connecting part respectively include a pressure cover and a sealing ring. The pressure cover and the sealing ring are fastened by bolts, and the center hole of the lip sealing ring is connected to the vacuum tube.

[0009] As a preferred technical solution, an annular shaft head is fixedly connected to the outer side of the inner cylinder, and a positioning step is provided at one end of the annular shaft head connected to the driving shaft.

[0010] As a preferred technical solution, the annular shaft head, the inner cylinder, the driving shaft, and the vacuum tube form a second cavity structure, and the inner wall of the second cavity structure is coated with a polytetrafluoroethylene coating.

[0011] As an optimal technical solution, a gap is left between the driving shaft and the vacuum tube, a hollow step is provided in the driving shaft, and a steam suction hole is provided at one end of the vacuum tube extending into the inner cylinder, and the steam suction hole is covered with polytetrafluoroethylene filter cloth.

[0012] As an optimal technical solution, it also includes a seat bearing, a driving wheel, and a support platform. The seat bearing is rotatably matched with the driving shaft, the driving wheel is fixedly connected to the driving shaft, and the driving wheel is transmission-connected to the output end of the external driving device, and can drive the driving shaft to drive the inner cylinder to rotate with its axis as the rotating axis.

[0013] As a preferred technical solution, a fixing plate is fixedly connected to the support platform, and the fixing plate is fixedly connected to the vacuum tube through a connecting plate. The connecting plate and the fixing plate are fixedly connected by bolts, and a mounting hole is opened on the connecting plate, and a rubber connecting ring is provided in the mounting hole, and the bolt passes through the rubber connecting ring.

[0014] A vacuum dryer comprises any one of the above-mentioned vacuum sealing devices for rotary drying of high-purity quartz.

[0015] The beneficial effects of the present invention are:

[0016] (1) In the present invention, a third seal is provided between the rotating mating surface of the driving shaft and the vacuum tube. When the packing wears within a certain range through the packing seal, the packing can be continued to be used by adjusting the compression of the sealing cover. This reduces the replacement cycle of the seal, ensures the sealing effect, and increases the service life of the seal.

[0017] (2) In the present invention, the connection surfaces of the inner cylinder, the vacuum tube and the driving shaft are sealed by setting the first sealing member, the second sealing member and the third sealing member, thereby improving the sealing effect, effectively preventing the overflow of high-purity quartz sand materials, and significantly improving the sealing effect of the rotary drying vacuum pumping structure.

[0018] (3) In the present invention, the flexible rubber connecting ring is provided to limit the rotation of the vacuum tube along with the inner cylinder, and to compensate for the radial displacement caused by the rotation of the driving shaft when there is a radial assembly error between the driving shaft and the annular shaft head, thereby protecting the lip sealing surface of the first sealing member and the packing sealing surface of the third sealing member on the vacuum tube, effectively preventing leakage caused by damage to the sealing surface due to radial displacement, ensuring the normal wear of the sealing surface, and significantly improving the service life of the seal.

[0019] (4) In the present invention, in places where rust may be generated during production, polytetrafluoroethylene is sprayed on the inner surface of the cavity between the lip sealing surface of the first seal and the packing sealing surface of the third seal as an anti-corrosion treatment to prevent rust from forming. This ensures that even if the gap between the lip sealing surface worn by high-purity quartz sand during use is larger than the particle size of the quartz sand, since the inner cylinder is in a negative pressure state, when a small amount of condensed air sucked from the O-ring sealing surface or the packing sealing surface is adsorbed on the inner surface of the cavity between the first lip sealing surface and the third packing sealing surface, rust will not form. This effectively ensures the cleanliness of the drying environment required for the dried high-purity quartz sand material and significantly reduces the risk of iron ions from the carbon steel parts outside the equipment being mixed into the contaminated material. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a cross-sectional structure of a device provided in an embodiment of the present utility model;

[0021] Figure 2 The embodiment of the present invention provides Figure 1 A local enlarged structural diagram;

[0022] Figure 3 The embodiment of the present invention provides Figure 1 B is a schematic diagram of a local enlarged structure;

[0023] Figure numbers: 1. Inner cylinder; 11. Annular shaft head; 12. Sealing ring; 121. Support bearing; 122. Lip seal; 123. Gland; 2. Driving shaft; 21. Bearing with seat; 22. Support platform; 221. Fixing plate; 23. Sealing groove; 24. O-ring; 25. Driving wheel; 26. Hollow step; 261. Left section; 262. Middle section; 263. Oblique cone section; 264. Cylindrical section; 3. Vacuum cover; 31. Left front section; 311. Trapezoidal structure; 312. Steam suction hole; 32. Horizontal section; 33. Polytetrafluoroethylene filter cloth; 34. Fastening hole; 4. Vacuum tube; 41. Left section; 42. Left middle section; 43. Right middle section; 44. Connecting plate; 45. Vacuum gauge; 46. Connecting flange; 5. Packing; 6. Sealing gland; 61. Oblique cone surface; 7. Rubber connecting ring. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the embodiments described are 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 making creative efforts shall fall within the scope of protection of the present invention.

[0025] See Figure 1 A vacuum sealing device for rotary drying of high-purity quartz comprises an inner cylinder 1, a driving shaft 2, and a vacuum tube 4. The inner cylinder 1 is fixedly connected to the driving shaft 2, and both are rotatably matched with the vacuum tube 4. A third sealing member is provided between the rotating matching surfaces of the driving shaft 2 and the vacuum tube 4. The third sealing member comprises a filling groove opened in the matching surface and a sealing gland 6. A second sealing member is provided between the matching surfaces of the inner cylinder 1 and the driving shaft 2, and a first sealing member is provided between the matching surfaces of the inner cylinder 1 and the vacuum tube 4. The filling groove is filled with filler 5. The sealing gland 6 is detachably fixedly connected to the driving shaft 2, and can cause the filling groove to form a closed cavity structure.

[0026] See Figure 1 and Figure 2, the inner cylinder 1 is made of stainless steel, and an annular shaft head 11 and a sealing ring 12 are provided on it. A first sealing member is provided between the rotating mating surface of the inner cylinder 1 and the vacuum tube 4, and the first sealing member includes a sealing shell, a support bearing 121, and a lip sealing ring 122. The sealing shell has a closed first cavity structure, and the sealing shell includes a left connecting part and a right connecting part. In this embodiment, the left connecting part and the right connecting part respectively include a pressure cover 123 and a sealing ring 12, and the sealing ring 12 is fixedly connected to the inner cylinder 1. The sealing ring 12 is fixedly connected to the support bearing 121. The outer ring of the support bearing 121 is fixedly connected to the inner cylinder 1, and the inner ring is fixedly connected to the vacuum tube 4. A lip sealing ring 122 is provided between the support bearing 121 and the pressure cover 123, and the lip sealing ring 122 is provided with a through hole adapted to the vacuum tube 4. The through hole is tightly attached to the vacuum tube 4 to seal it. After the pressure cover 123 is fixedly connected to the sealing ring 12, the lip sealing ring 122 is also compressed in the axial direction;

[0027] It should be noted that the sealing ring 12 is made of stainless steel, the support bearing 121 and the pressure cover 123 are made of stainless steel, the lip sealing ring 122 is a stainless steel skeleton type with an auxiliary lip, and the outer material is fluorine-based rubber.

[0028] See Figure 1 A positioning step is provided at the right end of the annular shaft head 11, and a positioning boss is formed on the end of the driving shaft 2 connected to the annular shaft head 11 that is adapted to the positioning step. The annular shaft head 11 is fixedly connected to the driving shaft 2 by bolts, and a sealing groove 23 is provided on the connecting surface of the inner cylinder 1 and the driving shaft 2. In this embodiment, the sealing groove 23 is opened on the connecting surface of the left end of the driving shaft 2, and an O-ring 24 is provided in the sealing groove 23. The O-ring 24 forms a second sealing component. The material of the O-ring 24 is polytetrafluoroethylene rubber, and the material of the driving shaft 2 is carbon steel.

[0029] See Figure 1 、 Figure 3 , a gap is left between the driving shaft 2 and the vacuum tube 4, and a hollow step 26 is provided in the driving shaft 2, and the hollow step 26 includes a left section 261, a middle section 262, an oblique cone section 263, and a cylindrical section 264 arranged in sequence along the axial direction of the driving shaft 2. The inner diameter of the left section 261 of the hollow step 26 is larger than the outer diameter of the vacuum tube 4, which is a large gap fit, and the inner diameter of the middle section 262 of the hollow step 26 is slightly larger than the outer diameter of the vacuum tube 4, which is a micro gap fit. The diameter of the left section 261 is larger than the diameter of the middle section 262, and the right side of the hollow step 26 is the oblique cone section 263 and the cylindrical section 264. The advantage of this arrangement is that it facilitates the installation and disassembly of the vacuum tube 4 and reduces the risk of dynamic and static interference between the vacuum tube 4 and the hollow section in the driving shaft 2. The oblique cone section 263, the cylindrical section 264 and the oblique cone surface 61 form a compacted trapezoidal cavity required for the packing 5, which improves the fit of the packing 5 to the inner and outer sealing surfaces of the third sealing cavity, thereby improving the sealing effect;

[0030] The area enclosed by the oblique cone section 263, the cylindrical surface section 264, the oblique cone surface 61, and the right middle section 43 forms a third sealing cavity. The packing 5 is made of asbestos polytetrafluoroethylene and is arranged in the third sealing cavity formed between the right side of the hollow step 26 on the driving shaft 2 and the right middle section 43 of the vacuum tube 4; the packing 5 has a specification of 10×10mm and is wound in the third sealing cavity for no less than 7 turns; the right side pressing surface of the sealing cover 6 is an oblique cone surface 61. The advantage of this design is that it is conducive to the compaction of the packing 5 and its close fit with the inside and outside of the third sealing cavity, thereby improving the sealing effect. After the sealing cover 6 compresses the packing 5, the remaining compressible space is no less than 20mm to ensure the range in which the packing 5 can continue to be compressed after wear, thereby improving the service life of the packing seal.

[0031] See Figure 1 The vacuum tube 4 includes a left front section 31, a horizontal section 32, a left section 41, a left middle section 42, and a right middle section 43 which are fixed and connected in sequence. The left front section 31 and the left section 41 are both located in the inner cylinder 1, the left middle section 42 is located in the annular shaft head 11 and the driving shaft 2, and part of the right middle section 43 is located in the driving shaft 2 and partly extends out of the driving shaft 2; the left front section 31 is arranged at an oblique upward angle to the center line of the driving shaft 2 to prevent the material in the inner cylinder 1 from rolling and causing the steam suction hole 312 to be blocked. The left front section 31 is Honeycomb structure, horizontal section 32 is a steel tube, left front section 31 and horizontal section 32 are covered with polytetrafluoroethylene filter cloth 33, and the outer side of polytetrafluoroethylene filter cloth 33 is wrapped with a vacuum cover 3, and the specification of polytetrafluoroethylene filter cloth 33 is 200 mesh or above; the highest end of the left front section 31 is a trapezoidal structure 311, which is also arranged with steam suction holes 312; fastening holes 34 are opened in the horizontal section 32 for connecting and fixing the vacuum cover 3 and the vacuum tube 4; the end of polytetrafluoroethylene filter cloth 33 is fixed to the vacuum tube 4 with a stainless steel clamp;

[0032] The vacuum tube 4 is made of stainless steel, and its left section 41 is finely machined and used to be fixedly connected to the horizontal section 32 in the vacuum cover 3 and the inner ring of the support bearing 121; its right middle section 43 is finely machined and serves as a packing sealing mating surface; the end of the right middle section 43 is also fixedly connected to a connecting flange 46, and a vacuum gauge 45 is fixedly connected to the right middle section 43.

[0033] See Figure 1The annular shaft head 11, the inner cylinder 1, the driving shaft 2, and the vacuum tube 4 are enclosed to form a second cavity structure. The inner wall of the second cavity structure is coated with a polytetrafluoroethylene coating, that is, a section of the inner cylinder 1 located in the second cavity structure, the inner wall of the annular shaft head 11, the positioning boss surface of the vacuum tube 4, the inner wall of the left section 261, the middle section 262, the left positioning boss surface of the driving shaft 2, and the outer peripheral surface of the left middle section 42 of the vacuum tube 4 are all sprayed with a polytetrafluoroethylene coating on the cavity surface, which is used for corrosion protection of the outer carbon steel part of the vacuum tube 4 to prevent condensed water from generating rust and being sucked into the inner cylinder 1 to contaminate the high-purity quartz sand material. The sprayed polytetrafluoroethylene coating is not less than 300um.

[0034] See Figure 1 , also includes a bearing with a seat 21, a driving wheel 25, and a support platform 22. The bearing with a seat 21 rotates with the driving shaft 2, the driving wheel 25 is fixedly connected to the driving shaft 2, and the driving wheel 25 is transmission-connected to the output end of the external driving device, and can drive the driving shaft 2 to drive the inner cylinder 1 to rotate with its axis as the rotating axis. The external driving device can be a driving motor, and the output end of the driving motor can be transmission-connected to the driving wheel 25 through a chain. The bearing with a seat 21 is fixedly connected to the support platform 22, its inner ring is fixedly connected to the driving shaft 2, and its outer ring is fixedly connected to the support platform 22.

[0035] A fixing plate 221 is fixedly connected to the support platform 22, and the fixing plate 221 is fixedly connected to the vacuum tube 4 through a connecting plate 44. The connecting plate 44 and the fixing plate 221 are fixedly connected by bolts, and a mounting hole is opened on the connecting plate 44. A rubber connecting ring 7 is provided in the mounting hole. The bolt passes through the rubber connecting ring 7. The rubber connecting ring 7 is set to be flexible so as to limit the rotation of the vacuum tube 4 with the inner cylinder 1, and to compensate for the radial displacement caused by the rotation of the driving shaft 2 when there is a radial assembly error between the driving shaft 2 and the annular shaft head 11, thereby protecting the sealing surface of the vacuum tube 4 and preventing leakage of the sealing surface due to radial displacement.

[0036] A vacuum dryer comprises the above-mentioned vacuum sealing device for rotary drying of high-purity quartz.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A vacuum sealing device for rotary drying of high-purity quartz, comprising an inner cylinder (1), a driving shaft (2), and a vacuum tube (4), wherein the inner cylinder (1) and the driving shaft (2) are fixedly connected and both are rotatably matched with the vacuum tube (4), characterized in that: A third sealing member is provided between the rotating mating surface of the driving shaft (2) and the vacuum tube (4), and the third sealing member comprises a filling groove and a sealing gland (6) provided in the mating surface. The filling groove is filled with a filler (5). The sealing gland (6) is detachably fixedly connected to the driving shaft (2), and is capable of forming a sealed cavity structure in the filling groove.

2. A vacuum sealing device for rotary drying of high-purity quartz according to claim 1, characterized in that: A first sealing member is provided between the rotating mating surfaces of the inner cylinder (1) and the vacuum tube (4), and the first sealing member comprises a sealing shell, a support bearing (121), and a lip-shaped sealing ring (122). The sealing shell is provided with a sealed first cavity structure, and the support bearing (121) and the lip-shaped sealing ring (122) are both provided in the first cavity structure. The outer ring of the support bearing (121) is fixed to the inner cylinder (1) through the sealing shell, and the inner ring of the support bearing (121) is fixed to the vacuum tube (4).

3. A vacuum sealing device for rotary drying of high-purity quartz according to claim 2, characterized in that: The inner cylinder (1) is fixedly connected to the driving shaft (2), and an O-type sealing ring (24) is provided at the connection surface between the inner cylinder (1) and the driving shaft (2).

4. The vacuum sealing device for rotary drying of high-purity quartz according to claim 2, characterized in that: The sealing shell comprises a left connecting portion and a right connecting portion, wherein the left connecting portion and the right connecting portion respectively comprise a gland (123) and a sealing ring (12), wherein the gland (123) and the sealing ring (12) are fastened by bolt connection, and the center hole of the lip sealing ring (122) is connected to the vacuum tube (4).

5. The vacuum sealing device for rotary drying of high-purity quartz according to claim 3, characterized in that: An annular shaft head (11) is fixedly connected to the outer side of the inner cylinder (1), and a positioning step is provided at one end of the annular shaft head (11) connected to the driving shaft (2).

6. A vacuum sealing device for rotary drying of high-purity quartz according to claim 5, characterized in that: The annular shaft head (11), the inner cylinder (1), the driving shaft (2), and the vacuum tube (4) enclose a second cavity structure, and the inner wall of the second cavity structure is coated with a polytetrafluoroethylene coating.

7. The vacuum sealing device for rotary drying of high-purity quartz according to claim 1, characterized in that: A gap is left between the driving shaft (2) and the vacuum tube (4); a hollow step (26) is provided in the driving shaft (2); one end of the vacuum tube (4) extending into the inner cylinder (1) is provided with a steam suction hole (312), and the steam suction hole (312) is coated with a polytetrafluoroethylene filter cloth (33).

8. The vacuum sealing device for rotary drying of high-purity quartz according to claim 1, characterized in that: The invention also includes a seat bearing (21), a driving wheel (25), and a support platform (22). The seat bearing (21) is rotatably matched with the driving shaft (2), the driving wheel (25) is fixedly connected to the driving shaft (2), and the driving wheel (25) is transmission-connected to the output end of an external driving device and can drive the driving shaft (2) to drive the inner cylinder (1) to rotate with its axis as the rotation axis.

9. A vacuum sealing device for rotary drying of high-purity quartz according to claim 8, characterized in that: A fixing plate (221) is fixedly connected to the support platform (22), and the fixing plate (221) is fixedly connected to the vacuum tube (4) via a connecting plate (44). The connecting plate (44) and the fixing plate (221) are fixedly connected via bolts, and a mounting hole is provided on the connecting plate (44). A rubber connecting ring (7) is provided in the mounting hole, and the bolt passes through the rubber connecting ring (7).

10. A vacuum dryer, characterized in that: The invention comprises a vacuum sealing device for rotary drying of high-purity quartz as described in any one of claims 1 to 9.

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