Temperature measuring and heat leakage preventing structure for heating chamber of vacuum furnace

Abstract

The utility model discloses a temperature measurement and heat leakage prevention structure for a heating chamber of a vacuum furnace, which particularly relates to the field of vacuum furnace structures and comprises a thermocouple, a first hole and a second hole which are respectively arranged on the heating chamber and a furnace pipe, a temperature measurement rod of the thermocouple penetrates through the first hole and the second hole and then extends into the furnace pipe, and a leakage prevention piece which forms a flexible bendable tubular object. A temperature measuring rod of the thermocouple is arranged in the tubular object in a penetrating mode, the two ends of the tubular object are connected with the inner wall of the heating chamber and the outer wall of the furnace pipe in a sealed mode respectively, the pipe diameter of the corrugated pipe is larger than that of the second hole, the pipe diameter of the second hole is larger than that of the first hole, and the two ends of the corrugated pipe are connected with the inner wall of the heating chamber and the outer wall of the furnace pipe in a sealed mode respectively. And the interference probability of the thermocouple can be reduced on the basis of expanding the hole II, the heat leakage can be reduced, the temperature measurement accuracy of the thermocouple is ensured, and the whole device can ensure the thermal expansion and cold contraction gap and prevent the heat leakage.

Description

Technical Field

[0001] This utility model relates to the field of vacuum furnace structure, and more specifically, to a temperature measurement and heat leakage prevention structure for the heating chamber of a vacuum furnace. Background Technology

[0002] During the operation of heat treatment equipment, due to the thermal expansion effect of metallic materials, the heating chamber and furnace structure will experience significant thermal displacement under the influence of the temperature field. According to thermodynamic simulation analysis, when the operating temperature reaches 800℃, the linear expansion of a typical industrial heating chamber can reach 12-18 mm / m, and its dynamic displacement is positively correlated with the temperature gradient. If the structural clearance is insufficient, mechanical interference between moving parts will induce continuous compressive stress, leading to plastic deformation or even fracture failure of the thermocouple protective sheath.

[0003] However, while excessively increasing the gap size can alleviate mechanical interference, it also creates heat conduction channels, causing local temperature field distortion (with a maximum deviation of ±45℃), making it difficult for the temperature readings at the measuring points to accurately reflect the thermodynamic state inside the furnace. This contradiction between mechanical reliability and thermal efficiency has become a key technical bottleneck restricting the improvement of measurement accuracy in high-temperature heat treatment equipment. Utility Model Content

[0004] In order to overcome the above-mentioned defects of the prior art, the embodiments of this utility model provide a temperature measurement and heat leakage prevention structure for the heating chamber of a vacuum furnace. The technical problem to be solved by this utility model is: how to balance the significant dynamic displacement between the heating chamber and the furnace shell caused by the thermal expansion effect of the metal material and the problem of controlling the size of the reserved heat insulation gap.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber, comprising a thermocouple, a hole one and a hole two respectively opened on the heating chamber and the furnace shell, the temperature measuring rod of the thermocouple passing through the hole one and the hole two and extending into the interior of the furnace shell, and also including a leak-proof component, the leak-proof component forming a flexible and bendable tubular object, the temperature measuring rod of the thermocouple passing through the tubular object, and the two ends of the tubular object being sealed and connected to the inner wall of the heating chamber and the outer wall of the furnace shell respectively.

[0006] In a preferred embodiment, the leak-proof component includes stacked blocks, specifically including blocks, guides, and clearance holes. The two end faces of adjacent blocks are fitted together and movable. The blocks at both ends are connected to the heating chamber and the furnace liner, respectively. Each block is provided with clearance holes. The clearance holes closer to the furnace liner have a larger diameter than the clearance holes farther from the furnace liner. Several clearance holes form a tubular structure. The guides are used to guide the movement of two adjacent blocks.

[0007] In a preferred embodiment, the guide includes a sliding member and a groove that make sliding contact. Between the contact end faces of two adjacent blocks, a sliding member is provided on one end face and a groove is provided on the other end face. The sliding member is a sliding ridge.

[0008] In a preferred embodiment, the guide includes a sliding member and a groove that are slidably connected. Between the contact end faces of two adjacent blocks, a sliding member is provided on one end face and a groove is provided on the other end face. The sliding member includes a flexible segment and a protrusion. The protrusion is fitted into the groove and slides in contact with it. The protrusion is connected to the corresponding position of the block through the flexible segment.

[0009] In a preferred embodiment, the flexible segment is made of a material with elastic or shape memory properties.

[0010] In a preferred embodiment, the leak-proof component includes a corrugated pipe with a diameter larger than that of the second hole, which in turn is larger than that of the first hole. Both ends of the corrugated pipe are respectively sealed to the inner wall of the heating chamber and the outer wall of the furnace liner.

[0011] In a preferred embodiment, the device includes a thermocouple, two holes (a first hole and a second hole) respectively opened on the heating chamber and the furnace shell, the temperature measuring rod of the thermocouple passing through the first hole and the second hole and extending into the interior of the furnace shell, and also includes an opening and closing component, specifically including an opening and closing plate and a semi-arc groove. The two opening and closing plates are symmetrically rotated and placed in the gap between the heating chamber and the furnace shell. The opening and closing plates are provided with semi-arc grooves. The diameter of the second hole is larger than the diameter of the circle enclosed by the two semi-arc grooves. The diameter of the circle enclosed by the two semi-arc grooves is larger than or equal to the diameter of the first hole.

[0012] The technical effects and advantages of this utility model are as follows:

[0013] By setting up leak-proof components, the probability of thermocouple interference can be reduced on the basis of enlarging the second hole, and heat leakage can also be reduced, ensuring the accuracy of thermocouple temperature measurement. This ensures that the entire device can both guarantee the thermal expansion and contraction gap and prevent heat leakage. Attached Figure Description

[0014] The accompanying drawings are provided to further understand the technical solution of this utility model and constitute a part of this utility model. The embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0015] Figure 1 This is an assembly drawing of the thermocouple and leak-proof component in this utility model.

[0016] Figure 2 This is a structural diagram of one form of the leak-proof component in this utility model.

[0017] Figure 3 This is a structural diagram of the clearance hole in this utility model.

[0018] Figure 4 This is a structural diagram of the sliding component with a flexible section in this utility model.

[0019] Figure 5 This is a structural diagram of the corrugated pipe in this utility model.

[0020] Figure 6 This is a structural diagram of the hinged plate in this utility model.

[0021] The attached figures are labeled as follows: 10, thermocouple; 20, leak-proof component; 21, stacking block; 211, block; 212, guide component; 2121, sliding component; 2122, slide groove; 213, clearance hole; 22, bellows; 23, opening and closing component; 231, opening and closing plate; 232, semi-circular groove. Detailed Implementation

[0022] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely illustrative of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0023] A temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber includes a thermocouple 10 and a leak-proof component 20. The thermocouple 10 is externally connected to the outer wall of the heating chamber via a flange structure. The temperature measuring rod of the thermocouple 10 passes through the side wall of the heating chamber and the furnace shell and extends into the furnace shell to measure the real-time temperature inside the furnace shell.

[0024] When thermal expansion occurs, because the thermal expansion coefficients of the heating chamber and the furnace are different, the holes 1 and 2 opened on the heating chamber and the furnace will move relative to each other as thermal expansion occurs, causing the positions of the originally aligned holes 1 and 2 to shift. At the same time, the temperature measuring rod of the thermocouple 10 passing through holes 1 and 2 will be subjected to the side wall stress of holes 1 and 2, resulting in bending or even breakage.

[0025] To solve the above problems, this utility model is designed with the following structure:

[0026] Example 1

[0027] like Figures 1-3 The leak-proof component 20 includes a stacking block 21, which includes several blocks 211. Each block 211 is movably connected to the others by a guide 212. Each block 211 has a clearance hole 213 for accommodating the temperature measuring rod of the thermocouple 10.

[0028] Taking three blocks 211 as an example, blocks 211 are divided into blocks 211a, 211b, and 211c. Block 211a is detachably connected to the heating chamber via threaded fasteners, block 211c is detachably connected to the outer wall of the furnace liner via threaded fasteners, and the two end faces of block 211b are movably connected to blocks 211a and c via guide members 212, respectively.

[0029] The guide member 212 includes a sliding member 2121 and a sliding groove 2122. The sliding contact between the sliding member 2121 and the sliding groove 2122 restricts the positional relationship between the three blocks 211. For example, the sliding groove 2122 is opened on both blocks 211a and 211c, and the sliding member 2121 is provided on both end faces of block 211b.

[0030] The sliding component 2121 is a sliding edge, which can slide within the sliding groove 2122 to allow the two blocks 211 to move along the edge of the sliding groove 2122.

[0031] A clearance hole 213a is provided on block 211a, a clearance hole 213b is provided on block 211b, and a clearance hole 213c is provided on block 211c. The diameter of the clearance holes 213a, b, and c increases sequentially. In this way, when the furnace liner, which is sensitive to thermal expansion, moves the corresponding block 211, the clearance hole 213c can reserve enough space to prevent interference with the temperature measuring rod of the thermocouple 10, thereby protecting the thermocouple 10. Furthermore, the mutual shielding between multiple blocks 211 can reduce heat leakage.

[0032] Example 2

[0033] like Figures 1-4 Another leak-proof component 20 has the following design structure: it includes a stacking block 21, which includes several blocks 211. Each block 211 is movably connected to the others by a guide 212. Each block 211 has a clearance hole 213 for accommodating the temperature measuring rod of the thermocouple 10.

[0034] Taking three blocks 211 as an example, blocks 211 are divided into blocks 211a, 211b, and 211c. Block 211a is detachably connected to the heating chamber via threaded fasteners, block 211c is detachably connected to the outer wall of the furnace liner via threaded fasteners, and the two end faces of block 211b are movably connected to block 211 via guide members 212.

[0035] The guide member 212 includes a sliding member 2121 and a sliding groove 2122. The sliding connection between the sliding member 2121 and the sliding groove 2122 restricts the positional relationship between the three blocks 211. For example, the sliding groove 2122 is opened on both blocks 211a and 211c, and the sliding member 2121 is provided on both end faces of block 211b.

[0036] The sliding component 2121 includes a flexible section and a protrusion. The protrusion is connected to the corresponding block 211 through the flexible section. The protrusion is used for extrusion and sliding contact with the slide groove 2122.

[0037] In this embodiment, the width of the groove 2122 is greater than the diameter of the protrusion so that it does not interfere with the edge of the groove 2122 when the flexible section is bent.

[0038] The flexible section is made of a material that can still allow a certain degree of deformation at a high temperature of 1000℃ and can be restored after cooling, that is, a material with elastic or shape memory properties.

[0039] Specifically, these could be nickel-based high-temperature shape memory alloys (NiTiHf-Pd system), silicon carbide fiber-reinforced yttrium aluminum garnet ceramic matrix composites (SiC / YAG CMC), etc.

[0040] Because of the presence of the flexible section, Embodiment 2, in addition to allowing sliding parallel to the edge of the slide groove 2122 in Embodiment 1, also has a movement basis that can intersect the movement direction of the slide groove 2122, enabling 360° free sliding between adjacent blocks 211. This greatly improves the protection capability for thermocouples.

[0041] Example 3

[0042] like Figure 5 A bellows 22 is installed between the inner wall of the heating chamber and the outer wall of the furnace shell. The bellows 22 is detachably connected to the corresponding end face via threaded fasteners. The diameter of the bellows 22 is larger than the diameter of the holes one and two opened on the side walls of the heating chamber and the furnace shell. This allows the temperature measuring rod of the thermocouple 10 to move without interference when the heating chamber and the furnace shell undergo thermal expansion. Furthermore, the bellows 22 itself has excellent thermal insulation capabilities, thus preventing excessive heat leakage.

[0043] The advantage of the bellows 22 is that it can move freely in both the axial and radial directions.

[0044] For corrugated pipe 22, Master-Clip HT 1100 high-temperature flexible hose is the preferred choice, which is clearly marked as having a temperature resistance of up to 1100℃ and is suitable for high-temperature industrial environments. If the temperature occasionally peaks close to 1000℃, a multi-layer composite structure corrugated pipe can also be considered, such as an inner layer of high-temperature resistant alloy + an outer layer of heat-insulating ceramic fiber.

[0045] Example 4

[0046] like Figure 6 An opening and closing component 23 is provided between the heating chamber and the furnace shell, including an opening and closing plate 231 and a semi-arc groove 232. The two opening and closing plates 231 are symmetrically rotated and connected or suspended in the inner wall of the heating chamber and connected to the inner wall of the heating chamber. The two opening and closing plates 231 are symmetrically provided with semi-arc grooves 232 for clamping the temperature measuring rods of the thermocouple 10 on both sides. The diameter of the second hole opened on the furnace shell is larger than that of the first hole opened on the heating chamber. The diameter of the circular hole formed by the two semi-arc grooves 232 is smaller than that of the second hole. Therefore, when the two opening and closing plates 231 are in a natural hanging state, they can block the heat leaking out from the second hole, which can both protect the thermocouple 10 and reduce heat leakage.

[0047] Meanwhile, if the thermal expansion is too great, causing the temperature measuring rod to come into contact with the opening and closing plate 231 on one side and deflect it, the exposed space will only leak less heat, which can be corrected later by calculating the correction coefficient of thermal compensation.

[0048] Working principle of this utility model:

[0049] By setting the leak-proof component 20, the probability of interference to the thermocouple 10 can be reduced on the basis of enlarging the second hole, and the heat leakage can also be reduced to ensure the temperature measurement accuracy of the thermocouple 10.

[0050] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber, comprising a thermocouple (10), a hole one and a hole two respectively opened on the heating chamber and the furnace shell, wherein the temperature measuring rod of the thermocouple (10) extends into the furnace shell after passing through the hole one and the hole two, characterized in that: It also includes a leak-proof component (20), which forms a flexible and bendable tubular structure. The temperature measuring rod of the thermocouple (10) is inserted into the tubular structure, and the two ends of the tubular structure are respectively sealed to the inner wall of the heating chamber and the outer wall of the furnace.

2. The vacuum furnace heating chamber temperature measurement and heat leakage prevention structure according to claim 1, characterized in that: The leak-proof component (20) includes stacked blocks (21), specifically including blocks (211), guides (212), and clearance holes (213). The two end faces of adjacent blocks (211) are fitted together and movable. The blocks (211) at both ends are connected to the heating chamber and the furnace liner, respectively. Each block (211) is provided with clearance holes (213). The clearance holes (213) closer to the furnace liner have a larger diameter than the clearance holes (213) farther away from the furnace liner. Several clearance holes (213) form a tubular structure. The guides (212) are used to guide the movement of two adjacent blocks (211).

3. The temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber according to claim 2, characterized in that: The guide (212) includes a sliding member (2121) and a sliding groove (2122) that have slidable contact. Between the contact end faces of two adjacent blocks (211), a sliding member (2121) is provided on one end face and a sliding groove (2122) is provided on the other end face. The sliding member (2121) is a sliding edge.

4. The temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber according to claim 2, characterized in that: The guide member (212) includes a sliding member (2121) and a sliding groove (2122) that are slidably connected. Between the contact end faces of two adjacent blocks (211), the sliding member (2121) is provided on one end face and the sliding groove (2122) is provided on the other end face. The sliding member (2121) includes a flexible segment and a protrusion. The protrusion is fitted into the sliding groove (2122) and slides in contact with it. The protrusion is connected to the corresponding position of the block (211) through the flexible segment.

5. The temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber according to claim 4, characterized in that: The flexible segment is made of a material with elastic or shape memory properties.

6. The temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber according to claim 1, characterized in that: The leak-proof component (20) includes a corrugated pipe (22), the diameter of which is larger than the diameter of the second hole, and the diameter of the second hole is larger than the diameter of the first hole. The two ends of the corrugated pipe (22) are respectively sealed to the inner wall of the heating chamber and the outer wall of the furnace.

7. A temperature measurement and heat leakage prevention structure for a vacuum furnace heating chamber, comprising a thermocouple (10), a hole one and a hole two respectively opened on the heating chamber and the furnace shell, wherein the temperature measuring rod of the thermocouple (10) extends into the furnace shell after passing through the hole one and the hole two, characterized in that: It also includes an opening and closing component (23), specifically including an opening and closing plate (231) and a semi-arc groove (232). The two opening and closing plates (231) are symmetrically rotated and placed in the gap between the heating chamber and the furnace shell. The opening and closing plate (231) is provided with a semi-arc groove (232). The diameter of the second hole is larger than the diameter of the circle formed by the two semi-arc grooves (232). The diameter of the circle formed is larger than or equal to the diameter of the first hole.

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