High-efficiency thermal insulation cylinder for single crystal furnace and single crystal furnace

Abstract

The utility model provides an efficient thermal insulation cylinder for a single crystal furnace and the single crystal furnace, the efficient thermal insulation cylinder comprises an upper thermal insulation cylinder, a middle thermal insulation cylinder and a lower thermal insulation cylinder which are sequentially and coaxially arranged from top to bottom, and the outer diameter of the upper thermal insulation cylinder is smaller than that of the middle thermal insulation cylinder; the upper heat preservation cylinder and the middle heat preservation cylinder are connected through a horizontal connecting piece, the upper heat preservation cylinder and the middle heat preservation cylinder are sleeved with a first soft felt and a second soft felt respectively, the outer side of the first soft felt and the inner side of the second soft felt are located on the same vertical plane, and the bottom of the first soft felt is connected with the horizontal connecting piece. The first soft felt is sleeved with a third soft felt, the bottom of the third soft felt is connected with the top of the second soft felt, and the horizontal height of the bottom of the third soft felt is lower than the horizontal height of the horizontal connecting piece.

Description

Technical Field

[0001] The utility model relates to the technical field of single-crystal silicon production, and particularly relates to an efficient heat preservation cylinder for a single-crystal furnace and a single-crystal furnace. Background Art

[0002] The production process of single-crystal silicon needs to be carried out in a high-temperature environment, and the thermal field in the single-crystal furnace needs to maintain a stable high-temperature state to ensure the melting and crystal growth of silicon materials. However, this process consumes a large amount of energy, and the performance of the heat preservation structure of the single-crystal furnace directly affects energy consumption and product quality.

[0003] In the existing heat preservation structure of the single-crystal furnace, the heat preservation cylinder usually adopts a laminated structure, so that the upper heat preservation cylinder, the middle heat preservation cylinder and the lower heat preservation cylinder are connected in sequence from top to bottom, and then corresponding heat preservation materials are sleeved outside the upper heat preservation cylinder, the middle heat preservation cylinder and the lower heat preservation cylinder respectively, so that the heat preservation materials also present a laminated structure. At present, under the laminated structure, the gaps between the upper and lower heat preservation cylinders are arranged opposite to the gaps between the upper and lower heat preservation materials, which is easy to leak heat. Moreover, in a high-temperature environment, it will cause the heat preservation materials to age, shrink and deform in structure, etc., thereby greatly affecting the heat preservation effect and resulting in large heat loss. Summary of the Utility Model

[0004] The purpose of the utility model is to provide an efficient heat preservation cylinder for a single-crystal furnace and a single-crystal furnace. The efficient heat preservation cylinder mainly adopts a dislocation structure, and the gaps between the upper and lower heat preservation cylinders and the gaps between the upper and lower soft felts are arranged in a dislocation manner, so as to reduce the heat leakage from the gaps between the two heat preservation cylinders, thereby improving the overall heat preservation performance of the single-crystal thermal field.

[0005] To solve the above technical problems, the utility model adopts the following solutions:

[0006] An efficient heat preservation cylinder for a single-crystal furnace, comprising an upper heat preservation cylinder, a middle heat preservation cylinder and a lower heat preservation cylinder which are coaxially arranged in sequence from top to bottom. The outer diameter of the upper heat preservation cylinder is smaller than that of the middle heat preservation cylinder. The upper heat preservation cylinder and the middle heat preservation cylinder are connected by a horizontal connecting piece. The outer sides of the upper heat preservation cylinder and the middle heat preservation cylinder are respectively sleeved with a first soft felt and a second soft felt. The outer side of the first soft felt and the inner side of the second soft felt are located in the same vertical plane, and the bottom of the first soft felt is connected to the horizontal connecting piece.

[0007] The first soft felt is sleeved with a third soft felt. The bottom of the third soft felt is connected to the top of the second soft felt, and the horizontal height of the bottom of the third soft felt is lower than the horizontal height of the horizontal connecting piece.

[0008] Further, the outer diameter of the middle heat preservation cylinder is equal to that of the lower heat preservation cylinder. The lower heat preservation cylinder is sleeved with a fourth soft felt. The bottom of the second soft felt is connected to the top of the fourth soft felt, and the horizontal height of the bottom of the second soft felt is lower than the horizontal height of the top of the lower heat preservation cylinder.

[0009] Furthermore, the inner diameter of the middle heat preservation cylinder is equal to that of the lower heat preservation cylinder, and the bottom of the middle heat preservation cylinder is engaged with the top of the lower heat preservation cylinder in an up-and-down manner.

[0010] Furthermore, the horizontal height of the outer side of the bottom of the middle heat preservation cylinder is higher than that of the inner side of the bottom, forming a groove; the horizontal height of the outer side of the top of the lower heat preservation cylinder is higher than that of the inner side of the bottom, forming a convex part, and the convex part is embedded in the groove, so that the bottom of the middle heat preservation cylinder is engaged with the top of the lower heat preservation cylinder in an up-and-down manner.

[0011] Furthermore, the inner diameter of the upper heat preservation cylinder is smaller than that of the middle heat preservation cylinder, and the outer diameter of the upper heat preservation cylinder is smaller than the inner diameter of the middle heat preservation cylinder, so that the upper heat preservation cylinder is connected to the inner side of the horizontal connecting member, and the middle heat preservation cylinder is connected to the outer side of the horizontal connecting member.

[0012] Furthermore, a carbon-carbon heat preservation cover is further arranged on the top of the upper heat preservation cylinder, a fixing felt is lapped at the carbon-carbon heat preservation cover, the fixing felt is located above the first soft felt and the second soft felt, and is hermetically connected to the first soft felt and the second soft felt.

[0013] A single crystal furnace includes a diversion cylinder and the high-efficiency heat preservation cylinder for a single crystal furnace as described above. The high-efficiency heat preservation cylinder is sleeved outside the diversion cylinder. A heat shield ring felt is arranged on the outer edge of the top of the diversion cylinder, and the outer edge of the top of the diversion cylinder is connected to the carbon-carbon heat preservation cover.

[0014] Furthermore, there is a gap between the outer edge of the top of the diversion cylinder and the carbon-carbon heat preservation cover. A blocking layer is arranged inside the fixing felt of the high-efficiency heat preservation cylinder, and the blocking layer is embedded in the gap for heat insulation.

[0015] The beneficial effects of the present utility model:

[0016] The purpose of the present utility model is to provide a high-efficiency heat preservation cylinder for a single crystal furnace and a single crystal furnace. The high-efficiency heat preservation cylinder mainly adopts a dislocation structure, and the gaps between the upper and lower heat preservation cylinders and the gaps between the upper and lower soft felts are arranged in a dislocation manner, reducing the heat leakage through the gaps between the two heat preservation cylinders. Thus, the overall heat preservation performance of the single crystal thermal field is improved.

[0017] Moreover, the original horizontal connection between the middle heat preservation cylinder and the lower heat preservation cylinder is changed to an up-and-down engagement connection. Through the up-and-down engagement connection, the gap between the middle heat preservation cylinder and the lower heat preservation cylinder forms a Z shape. By increasing the air flow stroke through the Z shape and increasing the contact area, the heat leakage through the gap is reduced. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the dislocation structure of the high-efficiency heat preservation cylinder in Embodiment 1 of the present utility model;

[0019] Figure 2 Schematic diagram of the structure where the middle heat preservation cylinder and the lower heat preservation cylinder in Embodiment 1 of the present utility model are connected by upper and lower clamping

[0020] Figure 3 Schematic diagram of the structure of the single crystal furnace in Embodiment 2 of the present utility model

[0021] Explanation of reference numerals: 1 - upper heat preservation cylinder, 2 - middle heat preservation cylinder, 3 - lower heat preservation cylinder, 4 - horizontal connecting piece, 5 - first soft felt, 6 - second soft felt, 7 - fourth soft felt, 8 - third soft felt, 9 - carbon - carbon heat preservation cover, 10 - felt fixing piece, 101 - barrier layer, 11 - flow guide cylinder, 12 - heat shield ring felt, 13 - groove, 14 - convex part Detailed implementation manners

[0022] To enable those skilled in the art to better understand the technical solution of the present utility model, the present utility model will be further described in detail below with reference to the drawings and specific implementation manners, but the implementation manners of the present utility model are not limited thereto

[0023] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inner", "outer", "front", "rear", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this utility model is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model

[0024] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "provided with", "installed", "connected", "connected to" should be understood in a broad sense. For example, it 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations

[0025] The present utility model will be described in detail below by referring to the drawings and in combination with embodiments

[0026] Embodiment 1

[0027] With the rapid development of the new energy industry, the demand for single-crystalline silicon is increasing day by day. Improving production efficiency and reducing costs have become important issues in the industry. Therefore, reducing the thermal field power of the single-crystal furnace, that is, reducing heat loss while ensuring production quality, has become the focus of research. However, the existing technologies have the following problems:

[0028] 1. Heat loss: The existing thermal insulation structure of the single-crystal furnace usually consists of multiple layers of materials. However, in a high-temperature environment, the thermal conductivity of the thermal insulation materials may increase, resulting in relatively large heat loss.

[0029] 2. Thermal insulation structure design: The existing thermal insulation structure design may not be optimized enough to fully meet the requirement of reducing heat loss. For example, there may be a thermal bridge effect at the joints of the thermal insulation layer, increasing heat conduction.

[0030] 3. Material properties: When working at high temperatures for a long time, the thermal insulation materials may age, shrink, and deform in structure, which will affect the thermal insulation effect and increase heat loss.

[0031] 4. Maintenance and replacement: Due to the degradation of materials in a high-temperature environment, the thermal insulation structure may need to be maintained and replaced frequently, which not only increases costs but also affects production efficiency.

[0032] 5. Uniformity: The existing thermal insulation structure may not provide uniform thermal insulation effect throughout the thermal field, resulting in local overheating or overcooling, which affects the quality of single-crystalline silicon.

[0033] In summary, the present utility model considers redesigning a new thermal insulation cylinder structure for a single-crystal furnace, and focuses on the technical problem that the gaps between the upper and lower thermal insulation cylinders 3 in the existing thermal insulation structure of the single-crystal furnace are arranged opposite to the gaps between the upper and lower thermal insulation materials, which is prone to heat leakage. An efficient thermal insulation cylinder for a single-crystal furnace is proposed. The efficient thermal insulation cylinder mainly adopts a dislocation structure, and the gaps between the upper and lower thermal insulation cylinders 3 and the gaps between the upper and lower soft felts are arranged in a dislocation manner to reduce heat leakage through the gaps between the two thermal insulation cylinders, thereby improving the overall thermal insulation performance of the single-crystal thermal field.

[0034] In this embodiment, as Figure 1As shown in the figure, an efficient heat preservation cylinder for a single crystal furnace includes an upper heat preservation cylinder 1, a middle heat preservation cylinder 2, and a lower heat preservation cylinder 3 that are coaxially arranged from top to bottom in sequence. The outer diameter of the upper heat preservation cylinder 1 is smaller than that of the middle heat preservation cylinder 2. The upper heat preservation cylinder 1 and the middle heat preservation cylinder 2 are connected by a horizontal connecting member 4. A first soft felt 5 and a second soft felt 6 are respectively sleeved outside the upper heat preservation cylinder 1 and the middle heat preservation cylinder 2. The outer side of the first soft felt 5 and the inner side of the second soft felt 6 are located in the same vertical plane, and the bottom of the first soft felt 5 is connected to the horizontal connecting member 4. A third soft felt 8 is sleeved outside the first soft felt 5. The bottom of the third soft felt 8 is connected to the top of the second soft felt 6, and the horizontal height where the bottom of the third soft felt 8 is located is lower than the horizontal height where the horizontal connecting member 4 is located.

[0035] Specifically, the upper heat preservation cylinder 1, the middle heat preservation cylinder 2, and the lower heat preservation cylinder 3 are selected to adopt a laminated structure, that is, they are coaxially arranged from top to bottom in sequence. Among them, compared with the inner diameter of the middle heat preservation cylinder 2, the inner diameter of the upper heat preservation cylinder 1 is smaller. Then, the upper heat preservation cylinder 1 and the middle heat preservation cylinder 2 are connected by a horizontal connecting member 4. In order to reduce the heat leakage through the gap between the upper heat preservation cylinder 1 and the middle heat preservation cylinder 2, that is, to reduce the heat leakage through the gap between the upper heat preservation cylinder 1 and the horizontal connecting member 4 and the heat leakage through the gap between the middle heat preservation cylinder 2 and the horizontal connecting member 4. In this embodiment, a first soft felt 5 and a second soft felt 6 are sleeved outside the upper heat preservation cylinder 1 and the middle heat preservation cylinder 2. The purpose of the first soft felt 5 is to insulate the upper heat preservation cylinder 1, and the purpose of the second soft felt 6 is to insulate the middle heat preservation cylinder 2. And, a third soft felt 8 is sleeved outside the first soft felt 5. The horizontal height where the bottom of the third soft felt 8 is located is lower than the horizontal height where the horizontal connecting member 4 is located. At this time, the bottom of the third soft felt 8 is connected to the top of the second soft felt 6. Then, the gap between the third soft felt 8 and the second soft felt 6 is misaligned with the gap between the upper heat preservation cylinder 1 and the middle heat preservation cylinder 2, so that the third soft felt 8 can block the gap between the upper heat preservation cylinder 1 and the horizontal connecting member 4 and the gap between the middle heat preservation cylinder 2 and the horizontal connecting member 4 in the horizontal direction, and heat leakage through the gap can be avoided.

[0036] Moreover, the outer side of the first soft felt 5 and the inner side of the second soft felt 6 are located in the same vertical plane. When the horizontal height where the bottom of the third soft felt 8 is located is lower than the horizontal height where the horizontal connecting member 4 is located, the inner side of the third soft felt 8 fits with the outer side of the middle heat preservation cylinder 2, and there will be no gap between the third soft felt 8 and the middle heat preservation cylinder 2, and the heat preservation performance is better.

[0037] For the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3, since the heater is located between the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3 during actual use, and the insulation distance cannot be varied in diameter for safety, the outer diameter of the middle heat preservation cylinder 2 is equal to the outer diameter of the lower heat preservation cylinder 3. A fourth soft felt 7 is sleeved outside the lower heat preservation cylinder 3. The bottom of the second soft felt 6 is connected to the top of the fourth soft felt 7, and the horizontal height where the bottom of the second soft felt 6 is located is lower than the horizontal height where the top of the lower heat preservation cylinder 3 is located, so that the gap between the second soft felt 6 and the fourth soft felt 7 is misaligned with the gap between the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3, which can avoid heat leakage through the gap.

[0038] Moreover, in order to improve the heat preservation performance of the heat preservation cylinder, in this embodiment, the original horizontal connection between the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3 is changed to an up-and-down clamping connection. Through the up-and-down clamping connection, the gap between the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3 forms a Z shape. By increasing the air flow path with the Z shape and increasing the contact area, heat leakage through the gap can be reduced.

[0039] Specifically, as Figure 2 shown, the horizontal height of the outer side of the bottom of the middle heat preservation cylinder 2 is higher than the horizontal height of the inner side of the bottom, forming a groove 13; the horizontal height of the outer side of the top of the lower heat preservation cylinder 3 is higher than the horizontal height of the inner side of the bottom, forming a convex part 14. The convex part 14 is embedded in the groove 13, so that the bottom of the middle heat preservation cylinder 2 and the top of the lower heat preservation cylinder 3 are connected by up-and-down clamping.

[0040] Through the up-and-down clamping connection, the matching relationship between the middle heat preservation cylinder 2 and the lower heat preservation cylinder 3 can be changed to a self-weight closed matching. Thus, the problem of heat leakage through the thermal field gap can be further solved. Based on the principle of the up-and-down clamping connection, the matching relationship between the horizontal connecting piece 4 and the upper heat preservation cylinder 1 and the matching relationship between the horizontal connecting piece 4 and the middle heat preservation cylinder 2 can also be changed to make them all rely on self-weight closed matching.

[0041] Embodiment 2

[0042] Based on the efficient heat preservation cylinder for a single crystal furnace provided in Embodiment 1, in this embodiment, a single crystal furnace is provided, including a guiding cylinder 11 and an efficient heat preservation cylinder for a single crystal furnace. The efficient heat preservation cylinder is sleeved outside the guiding cylinder 11, which can reduce heat leakage through the gap between the heat preservation cylinders, thereby improving the overall heat preservation performance of the single crystal thermal field.

[0043] Specifically, as Figure 3As shown, a carbon-carbon heat insulation cover 9 is further provided at the top of the upper heat insulation cylinder 1. A fixing felt 10 is lapped at the carbon-carbon heat insulation cover 9. The fixing felt 10 is located above the first soft felt 5 and the second soft felt 6 and is hermetically connected to the first soft felt 5 and the second soft felt 6. A heat shield ring felt 12 is provided at the outer edge of the top of the draft tube 11, and the outer edge of the top of the draft tube 11 is connected to the carbon-carbon heat insulation cover 9.

[0044] There is a gap between the outer edge of the top of the draft tube 11 and the carbon-carbon heat insulation cover 9. Then, a baffle layer 101 is provided inside the fixing felt 10 of the high-efficiency heat insulation cylinder, and an additional 20-mm fixing felt 10 is added. The baffle layer 101 is embedded in the gap for heat insulation, which can reduce heat loss.

[0045] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principle of the present invention. However, the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. An efficient heat preservation cylinder for a single crystal furnace, characterized in that It includes an upper heat preservation cylinder (1), a middle heat preservation cylinder (2) and a lower heat preservation cylinder (3) which are coaxially arranged from top to bottom in sequence. The outer diameter of the upper heat preservation cylinder (1) is smaller than that of the middle heat preservation cylinder (2). The upper heat preservation cylinder (1) and the middle heat preservation cylinder (2) are connected by a horizontal connecting piece (4). First soft felts (5) and second soft felts (6) are sleeved outside the upper heat preservation cylinder (1) and the middle heat preservation cylinder (2) respectively. The outer side of the first soft felt (5) and the inner side of the second soft felt (6) are located in the same vertical plane, and the bottom of the first soft felt (5) is connected to the horizontal connecting piece (4). A third soft felt (8) is sleeved outside the first soft felt (5). The bottom of the third soft felt (8) is connected to the top of the second soft felt (6), and the horizontal height where the bottom of the third soft felt (8) is located is lower than the horizontal height where the horizontal connecting piece (4) is located.

2. The high-efficiency heat preservation cylinder for a single crystal furnace according to claim 1, wherein The outer diameter of the middle heat preservation cylinder (2) is equal to that of the lower heat preservation cylinder (3). A fourth soft felt (7) is sleeved outside the lower heat preservation cylinder (3). The bottom of the second soft felt (6) is connected to the top of the fourth soft felt (7), and the horizontal height where the bottom of the second soft felt (6) is located is lower than the horizontal height where the top of the lower heat preservation cylinder (3) is located.

3. The high-efficiency heat preservation cylinder for a single crystal furnace according to claim 1, wherein The inner diameter of the middle heat preservation cylinder (2) is equal to that of the lower heat preservation cylinder (3). The bottom of the middle heat preservation cylinder (2) and the top of the lower heat preservation cylinder (3) are connected by upper and lower snap connections.

4. The high-efficiency heat preservation cylinder for a single crystal furnace according to claim 3, wherein The horizontal height of the outer side at the bottom of the middle heat preservation cylinder (2) is higher than the horizontal height of the inner side at the bottom, forming a groove (13); the horizontal height of the outer side at the top of the lower heat preservation cylinder (3) is higher than the horizontal height of the inner side at the bottom, forming a convex part (14). The convex part (14) is embedded in the groove (13) so that the bottom of the middle heat preservation cylinder (2) and the top of the lower heat preservation cylinder (3) are connected by upper and lower snap connections.

5. The high-efficiency heat preservation cylinder for a single crystal furnace according to claim 1, characterized in that The inner diameter of the upper heat preservation cylinder (1) is smaller than that of the middle heat preservation cylinder (2), and the outer diameter of the upper heat preservation cylinder (1) is smaller than the inner diameter of the middle heat preservation cylinder (2), so that the upper heat preservation cylinder (1) is connected to the inner side of the horizontal connecting piece (4), and the middle heat preservation cylinder (2) is connected to the outer side of the horizontal connecting piece (4).

6. The high-efficiency heat preservation cylinder for a single crystal furnace according to claim 1, wherein A carbon-carbon heat preservation cover (9) is further arranged at the top of the upper heat preservation cylinder (1). A fixing felt (10) is lapped at the carbon-carbon heat preservation cover (9). The fixing felt (10) is located above the first soft felt (5) and the second soft felt (6) and is hermetically connected to the first soft felt (5) and the second soft felt (6).

7. A single crystal furnace, characterized in that, It includes a flow guiding cylinder (11) and a high-efficiency heat preservation cylinder for a single crystal furnace as described in any one of claims 1-6. The high-efficiency heat preservation cylinder is sleeved outside the flow guiding cylinder (11). A heat shield ring felt (12) is arranged on the outer edge of the top of the flow guiding cylinder (11). The outer edge of the top of the flow guiding cylinder (11) is connected to the carbon-carbon heat preservation cover (9).

8. A single crystal furnace according to claim 7, characterized in that, There is a gap between the outer edge of the top of the flow guiding cylinder (11) and the carbon-carbon heat preservation cover (9). A baffle layer (101) is arranged inside the fixing felt (10) of the high-efficiency heat preservation cylinder. The baffle layer (101) is embedded in the gap for heat insulation.

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