Glue pouring and sealing method for electric heating tube

Abstract

The invention relates to the technical field of electric heating tube processing technologies, in particular to an electric heating tube glue pouring and sealing method which comprises the steps that an electric heating tube and a sample tube are prepared, a calibration lead-out rod and a calibration co-permeation layer are inserted into the sample tube, and a customized lead-out rod is manufactured; a customized lead-out rod is inserted into the electric heating tube; filling glue in batches; and solidifying and forming the glue. In order to solve the technical problem that an existing sealing process has defects, according to the glue pouring sealing method of the electric heating tube, by means of the first glue permeating hole formed in the customized lead-out rod, air extruded in the process that glue permeates towards insulating powder can be discharged from the first glue permeating hole, it is avoided that bubbles are formed when the glue flows into a glue sealing and pouring layer, and the sealing quality of the electric heating tube is improved. And the insulating and sealing effects of the sealing glue layer are further influenced.

Description

Technical Field

[0001] The invention relates to the technical field of electric heating tube processing technology, and in particular to a glue filling and sealing method for an electric heating tube. Background Art

[0002] When manufacturing electric heating tubes, the tube openings of the electric heating tubes need to be sealed. The main purpose of sealing is to prevent moisture in the air from entering the interior of the electric heating tubes, causing the insulating materials of the electric heating tubes to become damp, further reducing the insulating properties of the electric heating tubes, and causing product quality and safety issues.

[0003] In the current industrial electric heating tube production process, organic potting glue is often used to seal the tube mouth. The method is: mix the liquid organic glue with the corresponding curing agent and pour it into the tube mouth of the electric heating tube, then wait for a period of time, the glue will slowly solidify on the surface of the insulating powder layer, and finally form a hard, highly insulating solid substance to achieve the sealing of the tube mouth. However, in terms of the physical properties of the insulating material itself, it is essentially a granular material, and there are still air pores inside the insulating powder layer. Therefore, after the liquid glue is poured in, it will penetrate into the insulating powder layer, and then the air in the pores will float up to form bubbles, and finally cause pores to appear when the glue solidifies. Large and small pores mean the lack of insulation effect, and at the same time, it will cause moisture in the air to enter the inside of the electric heating tube, making the seal ineffective. Summary of the invention

[0004] In view of the technical problems of defects in the existing sealing process, the present invention provides a glue filling and sealing method for an electric heating tube, which utilizes a first glue seepage hole opened on a customized lead-out rod so that the air squeezed out during the glue seeping into the insulating powder can be discharged from the first glue seepage hole, thereby avoiding the air from flowing into the sealing glue layer to form bubbles, thereby affecting the insulation and sealing effects of the sealing glue layer.

[0005] The technical solution provided by the present invention is: a method for sealing an electric heating tube by filling glue, comprising: preparing an electric heating tube and a sample tube: preparing an electric heating tube and preparing a sample tube with the same structure as the electric heating tube, filling the electric heating tube and the sample tube with insulating powder to form an insulating powder layer; inserting a calibration lead-out rod into the sample tube: preparing a calibration lead-out rod, inserting the calibration lead-out rod into the insulating powder layer of the sample tube, and wrapping an insulating sheath at one end of the calibration lead-out rod by a heat shrinking process, and forming a gap D1 between the bottom end of the insulating sheath and the upper surface of the insulating powder layer after heat shrinking; calibrating the co-infiltration layer: filling the sample tube with no The glue passing through the gap D1 forms a calibration glue layer, and part of the glue in the calibration glue layer seeps down and mixes with the insulating powder to form a co-infiltration layer; when the glue in the sample tube is completely cured, the sample tube is cut open, and the distance between the bottom interface Q of the co-infiltration layer and its upper surface is measured and recorded as L; a customized lead-out rod is made: a first hollow section is opened on the top of the customized lead-out rod, a first glue infiltration hole is opened on the first hollow section, the lowest first glue infiltration hole is located above the bottom surface of the first hollow section, and the distance between the highest first glue infiltration hole and the lowest first glue infiltration hole is E, satisfying E>L, the first The area between the bottom surface of the hollow section and the lowest first glue seepage hole constitutes a first glue storage pit; insert a customized lead-out rod into the electric heating tube: mark the bottom interface Q in the insulating powder layer in the electric heating tube according to the distance L, insert the customized lead-out rod into the insulating powder layer of the electric heating tube, ensure that the highest first glue seepage hole is lower than the upper surface of the insulating powder layer, and at the same time, the lowest first glue seepage hole is lower than the marked bottom interface Q; and wrap the insulating sheath at one end of the customized lead-out rod through a heat shrink process, the bottom end of the heat-shrunk insulating sheath is higher than the highest first glue seepage hole, and the heat-shrunk insulating sheath is A gap D2 is formed between the bottom end of the sleeve and the upper surface of the insulating powder layer, and the gap D2 is equal to the gap D1; batch production glue pouring: glue covering the gap D2 is poured into the electric heating tube to form a sealing glue layer, the thickness of the sealing glue layer is consistent with the calibrated glue layer, and the glue in part of the sealing glue layer seeps into the insulating powder layer, and the glue squeezes out the air between the insulating powders. The air escapes into the atmosphere through the first glue seepage hole, or forms bubbles and flows into the first glue storage pit along with the glue passing through the first glue seepage hole; glue solidification and molding: wait for the glue in the electric heating tube to fully solidify and complete the sealing.

[0006] Optionally, after the glue is solidified and formed, a glue filling process is performed: glue is poured into the first hollow section until the glue covers the highest first glue penetration hole.

[0007] Optionally, after making the customized lead-out rod, the depth of the first glue pit is also measured and adjusted: insert the customized lead-out rod into the sample tube containing the insulating powder layer, pour glue with the same thickness as the calibrated glue layer into the sample tube, wait for the glue to seep in and solidify, and when the glue in the sample tube is completely solidified, cut the sample tube and the customized lead-out rod, measure and record the liquid level of the glue in the first glue pit, and adjust the depth of the first glue pit of the remaining customized lead-out rods according to the liquid level to ensure that the liquid level in the first glue pit is lower than the lowest first glue seepage hole; wherein, the depth of the first glue pit refers to the distance between the bottom surface of the first hollow section of the customized lead-out rod to the lowest first glue seepage hole.

[0008] Optionally, when making a customized lead-out rod, the distance between the first glue penetration hole located at the lowest position and the bottom surface of the first hollow section is greater than or equal to 2 mm.

[0009] Optionally, after inserting the customized lead-out rod into the electric heating tube, it also includes: making and inserting an air guide rod; making the air guide rod includes: opening a second hollow section at the top of the air guide rod, opening a second glue seepage hole on the second hollow section, the lowest second glue seepage hole is located above the bottom surface of the second hollow section, and the distance between the highest second glue seepage hole and the lowest second glue seepage hole is greater than L, and the area between the bottom surface of the second hollow section and the lowest second glue seepage hole constitutes a second glue storage pit; inserting the air guide rod includes: inserting the air guide rod into the insulating powder layer of the electric heating tube, ensuring that the highest second glue seepage hole is lower than the upper surface of the insulating powder layer, and at the same time the lowest second glue seepage hole is lower than the marked bottom interface Q.

[0010] Optionally, when inserting the customized lead-out rod into the electric heating tube, ensure that part of the first glue penetration hole is below the marked bottom interface Q.

[0011] Optionally, a distance E between the highest first glue seepage hole and the lowest first glue seepage hole on the first hollow segment satisfies E≥L+2 mm.

[0012] Optionally, the thickness of the calibration glue layer and the sealing glue layer is 8-10 mm.

[0013] The technical solution provided by the present invention has the following beneficial effects compared with the prior art: in response to the technical problem of defects in the existing sealing process, the present invention proposes a glue filling and sealing method for an electric heating tube, which utilizes a first glue seepage hole opened on a customized lead-out rod to allow the air squeezed out during the glue seepage into the insulating powder to be discharged from the first glue seepage hole, thereby avoiding the formation of bubbles in the sealing glue layer, which in turn affects the insulation and sealing effects of the sealing glue layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the implementation of the calibration co-diffusion layer proposed in an embodiment of the present invention.

[0015] Figure 2 This is a schematic structural diagram of a customized lead-out rod proposed in an embodiment of the present invention.

[0016] Figure 3 The present invention is a schematic diagram of an implementation of the glue filling and sealing method for an electric heating tube proposed in an embodiment of the present invention.

[0017] Figure 4 It is a partially enlarged schematic diagram of the batch production glue filling process proposed in an embodiment of the present invention.

[0018] Figure 5 This is a schematic diagram of an implementation of inserting a customized lead-out rod into an electric heating tube according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments.

[0020] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the invention. It should also be noted that, for the convenience of description, only the parts related to the invention are shown in the accompanying drawings. The words "first", "second", etc. described in the present invention are set for the convenience of describing the technical solution of the present invention, and have no specific limiting effect. They are all general references and do not constitute a limiting effect on the technical solution of the present invention. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention 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 therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" 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 a direct connection or an indirect connection through an intermediate medium, or it can be a connection between the insides of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Multiple technical solutions in the same embodiment, and multiple technical solutions in different embodiments, can be arranged and combined to form new technical solutions without contradictions or conflicts, all of which are within the scope of protection required by the present invention.

[0021] Example 1

[0022] Combined with Figure 1 To Attachment Figure 4 This embodiment proposes a method for sealing an electric heating tube with glue, including the preparation work first, that is, the electric heating tube 10 and the sample tube 11 need to be prepared, specifically: prepare the electric heating tube 10, and prepare the sample tube 11 with the same structure as the electric heating tube 10, fill the electric heating tube 10 and the sample tube 11 with insulating powder to form an insulating powder layer 12.

[0023] The insulating powder in the sample tube 11 is used for subsequent calibration of the co-infiltration layer 16, etc., and the insulating powder in the electric heating tube 10 is used for mass production. In practice, for the same model of electric heating tube 10, after the first use of the sample tube 11, the sample tube 11 can no longer be used in the subsequent glue filling and sealing process.

[0024] As attached Figure 1 As shown, after the sample tube 11 is prepared, a calibration lead rod 13 is inserted into the sample tube 11: the calibration lead rod 13 is prepared, inserted into the insulating powder layer 12 of the sample tube 11, and an insulating sheath 14 is wrapped at one end of the calibration lead rod 13 by a heat shrinking process, and a gap D1 is formed between the bottom end of the insulating sheath 14 and the upper surface of the insulating powder layer 12 after heat shrinking. Generally speaking, the distance between the bottom end of the insulating sheath 14 and the tube mouth of the sample tube 11 is set to about 20 mm, and the gap D1 formed is generally about 2 mm.

[0025] Then, the permeation layer 16 is calibrated: glue is poured into the sample tube 11 to cover the gap D1 to form a calibration glue layer 15, and the glue in the calibration glue layer 15 partially seeps down and mixes with the insulating powder to form the permeation layer 16. When the glue in the sample tube 11 is completely cured, the sample tube 11 is cut open, and the distance between the bottom interface Q of the permeation layer 16 and its upper surface is measured and recorded as L.

[0026] To simulate actual production, the temperature of the injected glue is set to 30-40°C. After the glue is injected into the sample tube 11, the thickness of the calibrated glue layer 15 should be controlled at 8-10 mm, generally controlled at about 8 mm. Since the glue has a strong viscosity and its fluidity is relatively weak, after the glue is injected into the sample tube 11, the process of the glue penetrating into the insulating powder layer 12 is relatively slow. Here, the thickness of the calibrated glue layer 15 generally refers to the thickness of the glue just injected into the sample tube 11. At this time, the thickness of the glue reduced due to penetration can be ignored.

[0027] As the glue slowly infiltrates and solidifies, the glue will mix with the insulating powder to form a co-infiltration layer 16. The fully solidified co-infiltration layer 16 is a hard glue-insulating powder mixture. The co-infiltration layer 16 will not loosen due to the cutting of the sample tube 11, so the cut co-infiltration layer 16 can be calibrated, and its bottom interface Q1 is calibrated. And mark the thickness of the co-infiltration layer 16, that is, the distance between the bottom interface Q and the upper surface of the co-infiltration layer 16 is L. Among them, after the insulating powder is mixed with glue, the change in the height of the upper surface can be ignored. Therefore, the upper surface of the co-infiltration layer 16 can be regarded as the upper surface of the insulating powder layer 12 when no glue is added. In this embodiment, an example is taken that the calibrated glue layer 15 with a thickness of 8 mm forms a co-infiltration layer 16 with a thickness of 6 mm, that is, L is taken as 6 mm.

[0028] In the above operation, the sample tube 11 completely simulates the actual electric heating tube 10 , so as to ensure that the subsequently calibrated co-infiltration layer 16 can be consistent with the co-infiltration layer 16 formed during the processing of the actual electric heating tube 10 .

[0029] After the co-infiltration layer 16 is calibrated, the customized lead-out rod 17 can be made: Figure 2 As shown, a first hollow section 170 is provided at the top of the customized lead-out rod 17, and a first glue seepage hole 171 is provided on the first hollow section 170. The lowest first glue seepage hole 171 is located above the bottom surface of the first hollow section 170, and the distance between the highest first glue seepage hole 171 and the lowest first glue seepage hole 171 is E, satisfying E>L, and the area between the bottom surface of the first hollow section 170 and the lowest first glue seepage hole 171 constitutes a first glue storage pit 172.

[0030] The customized lead-out rod 17 is improved on the basis of the lead-out rod of the common electric heating tube, and the improvement lies in that a hollow section is provided, and a plurality of first glue infiltration holes 171 are continuously provided in the height direction of the hollow section. Generally speaking, the first glue infiltration holes 171 are evenly arranged in the circumferential direction of the hollow section, but the aperture of the first glue infiltration holes 171 is generally small, and the density is relatively low, in order to avoid a large amount of glue from infiltrating into the first glue storage pit 172 at the same time as much as possible.

[0031] In this embodiment, E>L needs to be satisfied, that is, the length of the area including the first glue seepage holes 171 on the first hollow segment 170 must be greater than the thickness of the co-diffusion layer 16, that is, at least E>6 mm, preferably, E≥L+2 mm needs to be satisfied, that is, E≥8 mm at this time, so as to ensure that the first glue seepage holes 171 are set in a sufficient number of areas.

[0032] After the customized lead-out rod 17 is manufactured, it can be used for the processing and production of the electric heating tube 10. When the electric heating tube 10 is processed and produced, the customized lead-out rod 17 is first inserted into the electric heating tube 10: Figure 3As shown, in the electric heating tube 10, the bottom interface Q is marked in the insulating powder layer 12 according to the distance L. The customized lead-out rod 17 is inserted into the insulating powder layer 12 of the electric heating tube 10, ensuring that the highest first glue seepage hole 171 is lower than the upper surface of the insulating powder layer 12, and the lowest first glue seepage hole 171 is lower than the marked bottom interface Q. The insulating sheath 14 is wrapped by a heat shrinking process at one end of the customized lead-out rod 17, and the bottom end of the insulating sheath 14 after heat shrinkage is higher than the highest first glue seepage hole 171, and a gap D2 is formed between the bottom end of the insulating sheath 14 and the upper surface of the insulating powder layer 12 after heat shrinkage, and the gap D2 is equal to the gap D1.

[0033] In combination with the above steps, since the sample tube 11 completely simulates the actual electric heating tube 10, in the actual production of the electric heating tube 10, the bottom cross section Q of the permeation layer 16 in the electric heating tube 10 can be calibrated according to L on the electric heating tube 10 with reference to the sample tube 11. That is, in this step, the permeation layer 16 is calibrated for the electric heating tube 10 actually produced and processed with reference to the situation of calibrating the permeation layer 16 in the sample tube 11: the distance from the upper surface of the insulating powder layer 12 downward is L (L is taken as 6 mm in combination with the above text), which is marked as the bottom interface Q of the permeation layer 16 that can be formed in the electric heating tube 10.

[0034] It should be noted that the gap D2 and the gap D1 in this embodiment are not deliberately set, but are naturally formed due to the heat shrink process. In theory, for the electric heating tube 10 and the sample tube 11 of the same specification, when the insulating sheath 14 of the same specification is used, the gap D2 and the gap D1 are naturally equal, and in this embodiment, it can be 2 mm. For traditional electric heating tubes, one of the purposes of sealing the tube mouth is to ensure that the gap between the insulating sheath 14 and the insulating powder layer 12 is sealed in the glue, thereby ensuring the insulation effect.

[0035] Then you can start batch production of glue filling: Figure 3 As shown, glue is poured into the electric heating tube 10 to cover the gap D2 to form a sealing glue layer 18. The thickness of the sealing glue layer 18 is consistent with the calibrated glue layer 15. Part of the glue in the sealing glue layer 18 seeps into the insulating powder layer 12, and the glue expels the air between the insulating powders. The air can escape into the atmosphere through the first glue seepage hole 171, or form bubbles and then flow into the first glue storage pit 172 along with the glue passing through the first glue seepage hole 171.

[0036] In this step, the thickness of the sealing glue layer 18 is generally 8-10 mm, and in this embodiment, 8 mm is used. The temperature of the injected glue is also set to 30-40°C.

[0037] In this step, as the glue is poured in, the glue will slowly seep into the gaps between the insulating powder particles. As time goes by, the glue first seeps down to the height area where the highest first glue seepage hole 171 is located, and then gradually seeps down to a position not lower than the bottom interface Q.

[0038] From a microscopic perspective, as the glue seeps downward, the glue is actually displacing the air between the insulating powders. When the customized lead-out rod 17 is inserted into the insulating powder layer 12, the highest first glue seepage hole 171 is lower than the upper surface of the insulating powder layer 12, and the lowest first glue seepage hole 171 is lower than the marked bottom interface Q. Therefore, in the insulating powder layer 12 where the glue has not yet soaked, air can flow in the gaps between the insulating powders. Similarly, the displaced air can also easily flow out from the first glue seepage hole 171 on the customized lead-out rod 17.

[0039] At the same time, compared with the flow resistance, the liquid pressure in the area immersed in glue is strong, that is, the flow resistance of air drilling into the glue is greater, and the first glue seepage hole 171 is connected to the atmosphere and has smaller flow resistance. Therefore, during the glue infiltration process, the air can be discharged from the nearest first glue seepage hole 171 first.

[0040] For the part of the insulating powder layer 12 that has been immersed in glue, part of the glue will inevitably flow out from the first glue seepage hole 171 nearby and fall into the first glue storage pit 172 at the bottom of the first hollow section 170. This glue seepage process occurs simultaneously with the above-mentioned direct escape and discharge of air. Figure 4 As shown, when a small amount of air encounters a structural dead zone in the insulating powder layer 12, the glue will wrap the air, and the air will form small closed bubbles in the glue. As the glue overflows the glue seepage hole, part of the glue can flow out of the glue seepage hole together with part of the bubbles, thereby reducing the amount of bubbles retained in the glue. It should be understood that since the first glue storage pit 172 is inside the lead-out rod, the presence of bubbles in the first glue storage pit 172 will not affect the insulation performance of the product.

[0041] As the glue continues to seep downward, it will gradually approach the bottom interface Q marked previously, but the above-mentioned air expulsion process is also ongoing. The reason is that the lowest first glue seepage hole 171 is lower than the marked bottom interface Q. Even if the glue has penetrated deep enough at this time, the expelled air can still be discharged through the lowest first glue seepage hole 171, or the part of the first glue seepage hole 171 that is not higher than the bottom interface Q.

[0042] Preferably, when inserting the customized lead-out rod 17 into the electric heating tube 10, it is best to ensure that relatively more first glue seepage holes 171 are lower than the marked bottom interface Q, rather than only the lowest first glue seepage hole 171 being lower than the marked bottom interface Q, thereby ensuring the exhaust effect.

[0043] It should be noted that, although the amount of glue in the first glue storage pit 172 is increasing, it will not cover the lowest glue seepage hole, that is, it will not affect the exhaust process. The reason is that: since the first glue seepage hole 171 is arranged in the insulating powder layer 12, the glue needs to pass through the insulating powder and then flow through the first glue seepage hole 171, and the arrangement density of the first glue seepage hole 171 is not high, and the hole diameter is small, the glue can only flow into the first glue storage pit 172 in the form of "seepage", and the glue has a high viscosity and a low flow rate, and will be continuously intercepted and mixed by the insulating powder, and the rate of glue accumulation in the first glue storage pit 172 is very slow.

[0044] Also, since the insulating powder is in the form of particles and has a large specific surface area, the glue will adhere to its surface after seeping down, forming a stable "glue film", that is, the glue and the insulating powder will form a relatively stable mixed substance. According to the above content, the 8 mm sealing glue layer 18 can form about 6 mm of co-infiltration layer 16, and there is also a gap D2 of about 2 mm that needs to be sealed by some glue. Therefore, the glue that can seep out is only the "excess" glue, and the total amount of glue that can seep out of the glue seepage hole is very small.

[0045] In addition, although in the initial stage after the glue is poured in, the viscosity of the glue is relatively low and the fluidity is relatively good, and it can seep out of the first glue hole relatively easily, but as time goes by, the glue will gradually become more viscous due to the curing reaction, and its adhesion with the insulating powder will further increase, and the fluidity of the glue will continue to deteriorate, so the amount of glue seeping out through the first glue seepage hole 171 will gradually decrease.

[0046] Therefore, when making the customized lead-out rod 17, it is only necessary to appropriately deepen the depth of the first glue storage pit 172 and expand its storage capacity to ensure that before the glue is completely cured, the liquid level in the first glue storage pit 172 can be completely prevented from reaching the first glue seepage hole 171 at the lowest position. In a preferred embodiment, combined with practical experience, when making the customized lead-out rod 17, the distance between the first glue seepage hole 171 at the lowest position and the bottom surface of the first hollow section 170 is greater than or equal to 2 mm, that is, the highest liquid level in the first glue storage pit 172 is actually no greater than 2 mm.

[0047] After the above batch production glue pouring steps, as the glue gradually seeps and solidifies, the glue is completely solidified and formed, completing the sealing.

[0048] In contrast, the solid lead-out rod used in the conventional glue pouring method does not have the first glue seepage hole 171. The air squeezed out by the glue can only float up and drill into the glue because there is no first glue seepage hole 171 connected to the atmosphere. After the glue gradually solidifies, it remains in the glue to form pores, and its internal porosity is 80% to 90%.

[0049] However, through the method of this embodiment, the bubble rate inside the glue is greatly reduced after curing, to only about 20% to 30%. The remaining bubbles exist in the area close to the inner wall of the electric heating tube 10. Since these areas are far away from the customized lead-out rod 17, the gas discharge resistance is relatively large.

[0050] Furthermore, at the end of the above steps, that is, after the glue is solidified and formed, a glue filling process can be performed: that is, glue is poured into the first hollow section 170 until the glue submerges the highest first glue seepage hole 171. This step is to fill the first hollow section 170 with glue, that is, to raise the liquid level of the glue in the first glue storage pit 172 so that it submerges the area where the first glue seepage hole 171 is distributed, and further consolidate the sealing of the area where the first glue seepage hole 171 is located.

[0051] Example 2

[0052] Compared with the technical solution of Example 1, the glue filling and sealing method of an electric heating tube of the present embodiment can be improved as follows: after the customized lead-out rod 17 is made, it also includes the measurement and adjustment of the depth of the first glue storage pit 172: insert the customized lead-out rod 17 into the sample tube 11 containing the insulating powder layer 12, and pour glue with the same thickness as the calibrated glue layer 15 into the sample tube 11, waiting for the glue to seep in and solidify, and when the glue in the sample tube 11 is completely solidified, the sample tube 11 and the customized lead-out rod 17 are cut open, the liquid level of the glue in the first glue storage pit 172 is measured and recorded, and the depth of the first glue storage pit 172 of the remaining customized lead-out rods 17 is adjusted according to the liquid level to ensure that the liquid level in the first glue storage pit 172 is lower than the lowest first glue seepage hole 171; wherein, the depth of the first glue storage pit 172 refers to the distance between the bottom surface of the first hollow section 170 of the customized lead-out rod 17 to the lowest first glue seepage hole 171.

[0053] Combined with the description of the glue seeping into the first glue storage pit 172 through the first glue seepage hole 171 in Example 1, this embodiment proposes the measurement and adjustment of the depth of the first glue storage pit 172. The liquid level height that may be formed in the first glue storage pit 172 can be determined through a complete simulation experiment in the sample tube 11, and then the range value of the liquid level in the first glue storage pit 172 can be obtained accordingly, so that the bottom surface position of the first hollow section 170 in the customized lead-out rod 17 can be adjusted in a targeted manner to avoid the liquid level in the glue storage pit submerging the lowest first glue seepage hole 171 during actual production, which affects the exhaust.

[0054] Example 3

[0055] Combined with Figure 5 Compared with the technical solutions of Embodiment 1 or 2, the glue filling and sealing method of an electric heating tube in this embodiment can be improved as follows: after inserting the customized lead-out rod 17 into the electric heating tube 10, it also includes: making and inserting the gas guide rod 19.

[0056] The production of the gas guide rod 19 includes: opening a second hollow section 190 at the top of the gas guide rod 19, opening a second glue seepage hole 191 on the second hollow section 190, the lowest second glue seepage hole 191 is located above the bottom surface of the second hollow section 190, and the distance between the highest second glue seepage hole 191 and the lowest second glue seepage hole 191 is greater than L, and the area between the bottom surface of the second hollow section 190 and the lowest second glue seepage hole 191 constitutes a second glue storage pit 192.

[0057] Inserting the gas guide rod 19 includes: inserting the gas guide rod 19 into the insulating powder layer 12 of the electric heating tube 10, ensuring that the highest second glue penetration hole 191 is lower than the upper surface of the insulating powder layer 12, and the lowest second glue penetration hole 191 is lower than the marked bottom interface Q.

[0058] Consistent with the working principle of the customized lead-out rod 17 in Example 1, this embodiment can further utilize the second hollow section 190, the second glue seepage hole 191 and the second glue storage pit 192 opened on the air guide rod 19, so that the air squeezed out during the infiltration of glue into the insulating powder can be discharged from the second glue seepage hole 191, thereby avoiding rushing into the sealing glue layer 18 to form bubbles, thereby affecting the insulation and sealing effect of the sealing glue layer 18.

[0059] It is conceivable that the arrangement of the aperture, density, etc. of the second glue seepage holes 191 and the depth of the second glue storage pit 192 are preferably consistent with the arrangement of the first glue seepage holes 171 and the first glue storage pit 172 .

[0060] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A method for sealing an electric heating tube by filling with glue, characterized in that: include: Preparing an electric heating tube (10) and a sample tube (11): preparing an electric heating tube (10) and preparing a sample tube (11) having the same structure as the electric heating tube (10), and filling the electric heating tube (10) and the sample tube (11) with insulating powder to form an insulating powder layer (12); Inserting a calibration lead rod (13) into the sample tube (11): preparing the calibration lead rod (13), inserting the calibration lead rod (13) into the insulating powder layer (12) of the sample tube (11), and wrapping an insulating sheath (14) at one end of the calibration lead rod (13) by a heat shrinking process, so that a gap D1 is formed between the bottom end of the insulating sheath (14) and the upper surface of the insulating powder layer (12) after heat shrinking; Calibration of the co-infiltration layer (16): Glue is poured into the sample tube (11) to cover the gap D1 to form a calibration glue layer (15), and the glue in the calibration glue layer (15) partially infiltrates and mixes with the insulating powder to form a co-infiltration layer (16); when the glue in the sample tube (11) is completely cured, the sample tube (11) is cut open, and the distance between the bottom interface Q of the co-infiltration layer (16) and its upper surface is measured and recorded as L; Making a customized lead-out rod (17): a first hollow section (170) is provided on the top of the customized lead-out rod (17), a first glue seepage hole (171) is provided on the first hollow section (170), the lowest first glue seepage hole (171) is located above the bottom surface of the first hollow section (170), and the distance between the highest first glue seepage hole (171) and the lowest first glue seepage hole (171) is E, satisfying E>L, and the area between the bottom surface of the first hollow section (170) and the lowest first glue seepage hole (171) constitutes a first glue storage pit (172); Inserting a customized lead-out rod (17) into the electric heating tube (10): marking a bottom interface Q in the insulating powder layer (12) in the electric heating tube (10) according to a distance L, inserting the customized lead-out rod (17) into the insulating powder layer (12) of the electric heating tube (10), ensuring that the highest first glue seepage hole (171) is lower than the upper surface of the insulating powder layer (12), and at the same time, the lowest first glue seepage hole (171) is lower than the marked bottom interface Q; and wrapping the insulating sheath (14) at one end of the customized lead-out rod (17) through a heat shrinking process, the bottom end of the insulating sheath (14) after heat shrinking is higher than the highest first glue seepage hole (171), and a gap D2 is formed between the bottom end of the insulating sheath (14) and the upper surface of the insulating powder layer (12) after heat shrinking, and the gap D2 is equal to the gap D1; Batch production glue filling: Glue is poured into the electric heating tube (10) to cover the gap D2 to form a sealing glue layer (18), the thickness of the sealing glue layer (18) is consistent with the calibration glue layer (15), and the glue in the sealing glue layer (18) partially penetrates into the insulating powder layer (12), and the glue squeezes out the air between the insulating powders, and the air escapes into the atmosphere through the first glue penetration hole (171), or forms bubbles and flows into the first glue storage pit (172) along with the glue passing through the first glue penetration hole (171); Glue solidification and molding: wait for the glue in the electric heating tube (10) to fully solidify and complete the sealing.

2. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: After the glue is solidified and formed, a glue filling process is performed: glue is poured into the first hollow section (170) until the glue covers the highest first glue penetration hole (171).

3. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: After the customized lead-out rod (17) is manufactured, the method further includes measuring and adjusting the depth of the first glue storage pit (172): inserting the customized lead-out rod (17) into the sample tube (11) containing the insulating powder layer (12), pouring glue having the same thickness as the calibrated glue layer (15) into the sample tube (11), waiting for the glue to seep in and solidify, and when the glue in the sample tube (11) is completely solidified, cutting the sample tube (11) and the customized lead-out rod (17), measuring and recording the liquid level of the glue in the first glue storage pit (172), and adjusting the depth of the first glue storage pit (172) of the remaining customized lead-out rods (17) according to the liquid level, to ensure that the liquid level in the first glue storage pit (172) is lower than the lowest first glue seepage hole (171); wherein the depth of the first glue storage pit (172) refers to the distance between the bottom surface of the first hollow section (170) of the customized lead-out rod (17) and the lowest first glue seepage hole (171).

4. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: When the customized lead-out rod (17) is manufactured, the distance between the first glue penetration hole (171) located at the lowest position and the bottom surface of the first hollow section (170) is greater than or equal to 2 mm.

5. A method for sealing an electric heating tube by filling with glue according to claim 1, 3 or 4, characterized in that: After inserting the customized lead-out rod (17) into the electric heating tube (10), the method further includes: making and inserting a gas guide rod (19); The manufacturing of the gas guide rod (19) comprises: a second hollow section (190) is formed at the top of the gas guide rod (19), a second glue seepage hole (191) is formed on the second hollow section (190), the lowest second glue seepage hole (191) is located above the bottom surface of the second hollow section (190), and the distance between the highest second glue seepage hole (191) and the lowest second glue seepage hole (191) is greater than L, and the area between the bottom surface of the second hollow section (190) and the lowest second glue seepage hole (191) constitutes a second glue storage pit (192); Inserting the gas guide rod (19) comprises: inserting the gas guide rod (19) into the insulating powder layer (12) of the electric heating tube (10), ensuring that the highest second glue penetration hole (191) is lower than the upper surface of the insulating powder layer (12), and the lowest second glue penetration hole (191) is lower than the marked bottom interface Q.

6. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: When inserting the customized lead-out rod (17) into the electric heating tube (10), ensure that part of the first glue penetration hole (171) is lower than the marked bottom interface Q.

7. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: The distance E between the highest first glue seepage hole (171) and the lowest first glue seepage hole (171) on the first hollow section (170) satisfies E≥L+2 mm.

8. The method for sealing an electric heating tube by filling with glue according to claim 1, characterized in that: The thickness of the calibration glue layer (15) and the sealing glue layer (18) is 8-10 mm.

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