Molten salt energy storage system heating cable

Abstract

The utility model discloses a molten salt energy storage system heating cable, which comprises a heating cable and power leads, two ends of the heating cable are respectively connected with one power lead, the heating cable comprises a central heating wire core, an outer armor layer and a mineral insulating material layer between the heating wire core and the armor layer, and the power leads comprise middle conductive wire cores. The heating cable comprises a heating wire core and an insulating plastic layer wrapping the conductive wire core, the heating cable further comprises heat insulation wire cores, the heat insulation wire cores are arranged at the two ends of the heating wire core respectively, an armor layer and a mineral insulating material layer wrap the heat insulation wire cores, one end of each heat insulation wire core is connected with the heating wire core, and the other end of each heat insulation wire core is connected with the conductive wire core. The fused salt energy storage system heating cable further comprises a sealing sleeve, and the sealing sleeve is arranged at the joint of the heating cable and the power lead. The heating cable can isolate the heat of the heating wire core, thereby guaranteeing the safety of the power lead. The sealing of the mineral insulating material outside the heating wire core can be ensured, and the safety of the cable is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of pipeline heating, in particular to a heating cable for a molten salt energy storage system. Background Art

[0002] Molten salt energy storage technology is one of the most mainstream high-temperature heat storage technologies in the world. It has the advantages of no pollution, large capacity, small footprint, high waste heat utilization efficiency, and high power generation efficiency. There are many pipelines for molten salt flow in the molten salt energy storage system. In order to prevent the molten salt from solidifying when it encounters cold and causing pipeline blockage during the flow, the pipeline needs to be heated and insulated. The commonly used hot salt is a eutectic mixture of 60% sodium nitrate and 40% potassium nitrate, which can be used as a liquid between 260-550℃, which requires a heating cable to provide a heating temperature of 260-550℃.

[0003] In response to the high-temperature heating demand, in the prior art, the invention patent with the authorization announcement number CN 115474300 B discloses an oil-in-tube heating cable structure, device and heating method. The oil-in-tube heating cable structure includes: a heating wire core, whose head end is used to introduce an external power supply; a metal pipe sheath completely covers the heating wire core; a powdered mineral insulating material is filled inside the metal pipe sheath; wherein the extension direction of the heating wire core is roughly parallel to the axial direction of the metal pipe sheath, and the heating wire core, the metal pipe sheath and the mineral insulating material form a dense integrated structure; the mineral insulating material includes high-purity magnesium oxide powder, and at least one of high-crystallization aluminum oxide powder and silicon dioxide powder; the heating wire core is a metal alloy with small plastic deformation wrapped with a metal alloy with large surface load. The oil-in-tube heating cable structure has insulation and thermal conductivity properties, and also improves the reliability of the heating cable.

[0004] In the process of realizing the utility model, the inventors found that there are at least the following problems in the prior art: 1. The temperature of the heating core of the molten salt heating cable is much higher than that of the conventional heating cable, and the outer skin of the power lead is a plastic insulation layer. How to avoid the influence of the heating core on the insulation layer is a problem to be solved; 2. The mineral insulation material between the heating core and the metal pipe sheath needs to ensure good sealing to avoid the risk of leakage. Summary of the invention

[0005] In view of the deficiencies in the prior art, the utility model develops a molten salt energy storage system heating cable, which can isolate the heat of the heating wire core and ensure the safety of the power lead; it can ensure the sealing of the mineral insulating material outside the heating wire core and improve the safety of the cable.

[0006] The technical solution to the technical problem solved by the utility model is as follows: an embodiment of the utility model provides a molten salt energy storage system heating cable, comprising a heating cable and a power lead, wherein both ends of the heating cable are respectively connected to a power lead, the heating cable comprises a central heating core, an outer armor layer, and a mineral insulating material layer between the heating core and the armor layer, the power lead comprises a middle conductive core, and an insulating plastic layer wrapping the conductive core, the heating cable also comprises an insulating core, one insulating core is arranged at each end of the heating core, the armor layer and the mineral insulating material layer wrap the insulating core, one end of the insulating core is connected to the heating core, and the other end is connected to the conductive core; the molten salt energy storage system heating cable also comprises a sealing sleeve, the sealing sleeve is filled with sealant, and the sealing sleeve is arranged at the connection between the heating cable and the power lead.

[0007] As an optimization, the sealing sleeve and the armor layer are welded into one body.

[0008] As an optimization, the sealant is epoxy resin.

[0009] As an optimization, the interface between the heat-insulating core and the conductive core is located in the sealant.

[0010] As an optimization, the molten salt energy storage system heating cable also includes a heat dissipation sleeve, which is a round tube with openings at both ends. The heat dissipation sleeve is provided with at least one heat insulation core segment at both ends of the heating cable, and the heat dissipation sleeve wraps the armor layer, and the two ends of the heat dissipation sleeve are welded to the armor layer as a whole. The heat dissipation sleeve, the sealing sleeve, and the armor layer are all made of stainless steel.

[0011] As an optimization, the outer edges of the two end surfaces of the heat dissipation sleeve are chamfered.

[0012] As an optimization, a heat shrink tube is further provided at the interface between the heating cable and the power lead, and both ends of the heat shrink tube are located in the sealant.

[0013] As an optimization, the heating cable also includes auxiliary parts a and auxiliary parts b. Both auxiliary parts a and auxiliary parts b are round tubes with openings at both ends. Auxiliary parts a and auxiliary parts b are sleeved on the heating cable between the sealing sleeve and the heat dissipation sleeve. The outer sides of auxiliary parts a and auxiliary parts b are both provided with a regular hexagonal tightening section. The inner hole of auxiliary part a includes two parts. The end away from auxiliary part b is in contact with the armor layer, and the end close to auxiliary part b is provided with a threaded hole. The side of auxiliary part b close to auxiliary part a is provided with a corresponding external thread. Auxiliary parts a and auxiliary parts b can be used to fix the heating cable. After the heating cable passes through the fixing plate, auxiliary parts a and auxiliary parts b are respectively located on the upper and lower surfaces of the fixing plate. After the two are tightened, they can clamp the fixing plate to fix the heating cable.

[0014] As an optimization, a cap is further provided at one end of the auxiliary component b away from the auxiliary component a, and the cap is connected to the auxiliary component b by threads; or the end of the auxiliary component b away from the auxiliary component a is sealed with glue.

[0015] The effects provided in the summary of the invention are only the effects of the embodiments, not all the effects of the utility model. The above technical solution has the following advantages or beneficial effects:

[0016] 1. By setting up a heat-insulating core, the heat released and transferred from both ends of the heating core can be evacuated and isolated. The heating cable can isolate the heat of the heating core and ensure the safety of the power lead; by setting up a sealing sleeve, the sealing of the mineral insulating material outside the heating core can be guaranteed, thereby improving the safety of the cable.

[0017] 2. The heating wire core adopts iron-chromium-aluminum heating wire or nickel-chromium heating wire, the armor layer adopts stainless steel material, and the mineral insulation material layer adopts one or more of quartz, talc, and alumina. The heating temperature of the heating cable can reach thousands of degrees, and it has high mechanical protection strength.

[0018] 3. The heat dissipation efficiency of the heat-insulating core is improved by providing a heat dissipation sleeve. By chamfering the outer edges of the two end surfaces of the heat dissipation sleeve, the two ends of the heat dissipation sleeve become pointed, which facilitates the installation of the heating cable in the hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional diagram of an embodiment of the utility model.

[0020] Figure 2 This is a front view of an embodiment of the utility model.

[0021] Figure 3 for Figure 2 Cross-sectional view along CC direction.

[0022] Figure 4 for Figure 3 A partial enlarged view of the D area in the middle.

[0023] Figure 5 for Figure 3 A partial enlarged view of the E area.

[0024] Figure 6 It is a stereogram of the second embodiment of the utility model.

[0025] Figure 7 This is a front view of the second embodiment of the utility model.

[0026] Figure 8 for Figure 7 Cross-sectional view along the FF direction.

[0027] Among them: 1. Heating cable, 2. Power lead, 3. Heat dissipation sleeve, 4. Sealing sleeve, 5. Sealant, 6. Accessory a, 7. Accessory b, 8. Cover cap, 11. Heating core, 12. Mineral insulation material layer, 13. Armor layer on the outside, 14. Insulation core, 21. Conductive core, 22. Insulating plastic layer. DETAILED DESCRIPTION

[0028] In order to clearly illustrate the technical features of the present invention, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0029] Embodiment 1: Figures 1 to 5 An embodiment of the present utility model is as follows: Figure 1 As shown, a molten salt energy storage system heating cable comprises a heating cable 1 and a power lead 2. The two ends of the heating cable 1 are respectively connected to a power lead 2. Figure 4 , Figure 5 As shown, the heating cable 1 includes a central heating core 11, an outer armor layer 13, and a mineral insulating material layer 12 between the heating core 11 and the armor layer 13. The power lead 2 includes a middle conductive core 21 and an insulating plastic layer 22 wrapping the conductive core 21. The heating cable 1 also includes an insulating core 14, which is arranged at each end of the heating core 11. The armor layer 13 and the mineral insulating material layer 12 wrap the insulating core 14. One end of the insulating core 14 is connected to the heating core 11, and the other end is connected to the conductive core 21. Figure 3 As shown, the molten salt energy storage system heating cable also includes a sealing sleeve 4, which is filled with a sealant 5, and the sealing sleeve 4 is arranged at the connection between the heating cable 1 and the power lead 2. The sealing sleeve 4 is welded to the armor layer 13 as a whole. The sealant 5 is epoxy resin. The interface between the heat-insulating core 14 and the conductive core 21 is located in the sealant 5. The heating core 11 adopts iron-chromium-aluminum heating wire or nickel-chromium heating wire, the armor layer 13 adopts stainless steel material, and the mineral insulating material layer 12 adopts one or more of quartz, talc, and alumina. The heating cable 1 can reach a maximum temperature of 1000 degrees and has a high mechanical protection strength.

[0030] like Figure 3As shown, the molten salt energy storage system heating cable also includes a heat dissipation sleeve 3, which is a round tube with openings at both ends. At least one heat dissipation sleeve 3 is respectively provided on the heat insulation core 14 sections at both ends of the heating cable 1. The heat dissipation sleeve 3 wraps the armor layer 13, and the two ends of the heat dissipation sleeve 3 are welded to the armor layer 13 as a whole. The heat dissipation sleeve 3, the sealing sleeve 4, and the armor layer 13 are all made of stainless steel. By providing the heat dissipation sleeve 3, the heat dissipation efficiency of the heat insulation core 14 is improved. The outer edges of the two end faces of the heat dissipation sleeve 3 are chamfered. By chamfering the outer edges of the two end faces of the heat dissipation sleeve 3, the two ends of the heat dissipation sleeve 3 become pointed, which facilitates the installation of the heating cable in the hole during installation.

[0031] The heat-insulating core 14 and the conductive core 21 are solid copper wires, and the heating core 11 is made of iron-chromium-aluminum heating wire or nickel-chromium heating wire. The heat-insulating core 14 and the heating core 11 are heterogeneous materials and can be welded by laser welding. By setting the heat-insulating core 14, the heat released and transferred from both ends of the heating core 11 is evacuated and isolated. The heating cable can isolate the heat of the heating core and ensure the safety of the power lead; by setting the sealing sleeve 4, the sealing of the mineral insulating material outside the heating core can be ensured, thereby improving the safety of the cable.

[0032] Embodiment 2: Figures 6 to 8 This is the second embodiment of the utility model, which is different from the first embodiment in that: the heating cable also includes auxiliary parts a6 and b7, which are both round tubes with openings at both ends. Auxiliary parts a6 and b7 are sleeved on the heating cable 1 between the sealing sleeve 4 and the heat dissipation sleeve 3, and the outer sides of auxiliary parts a6 and b7 are both provided with a regular hexagonal tightening section; the inner hole of auxiliary part a6 includes two parts, one end away from auxiliary part b7 is in contact with the armor layer 13, and the end close to auxiliary part b7 is provided with a threaded hole, and the side of auxiliary part b7 close to auxiliary part a6 is provided with a corresponding external thread. Auxiliary parts a6 and b7 can be used to fix the heating cable. After the heating cable passes through the fixing plate, auxiliary parts a6 and b7 are respectively located on the upper and lower surfaces of the fixing plate. After the two are tightened, the fixing plate can be clamped to fix the heating cable.

[0033] A cover cap 8 is further provided at one end of the auxiliary component b7 away from the auxiliary component a6, and the cover cap 8 is connected to the auxiliary component b7 by threads.

[0034] Embodiment 3: The difference between Embodiment 3 and the first embodiment is that a heat shrink tube is further provided at the interface between the heating cable 1 and the power lead 2 , and both ends of the heat shrink tube are located in the sealant 5 .

[0035] Although the specific implementation methods of the utility model are described above in conjunction with the accompanying drawings, this does not limit the scope of protection of the utility model. On the basis of the technical solution of the utility model, various modifications or deformations that can be made by technical personnel in this field without creative work are still within the scope of protection of the utility model.

Claims

1. A molten salt energy storage system heating cable, comprising a heating cable (1) and a power lead (2), wherein both ends of the heating cable (1) are respectively connected to a power lead (2), the heating cable (1) comprises a central heating core (11), an outer armor layer (13), and a mineral insulating material layer (12) between the heating core (11) and the armor layer (13), the power lead (2) comprises a middle conductive core (21), and an insulating plastic layer (22) wrapping the conductive core (21), wherein: The heating cable (1) further comprises a heat-insulating core (14), one heat-insulating core (14) being arranged at each end of the heating core (11), the armor layer (13) and the mineral insulating material layer (12) wrapping the heat-insulating core (14), one end of the heat-insulating core (14) being connected to the heating core (11), and the other end being connected to the conductive core (21); the molten salt energy storage system heating cable further comprises a sealing sleeve (4), the sealing sleeve (4) being filled with a sealant (5), and the sealing sleeve (4) being arranged at the connection between the heating cable (1) and the power lead (2).

2. A molten salt energy storage system heating cable according to claim 1, characterized in that: The sealing sleeve (4) and the armor layer (13) are welded into one body.

3. The molten salt energy storage system heating cable according to claim 1, characterized in that: The sealant (5) is epoxy resin.

4. The molten salt energy storage system heating cable according to claim 1, characterized in that: The interface between the heat-insulating wire core (14) and the conductive wire core (21) is located in the sealant (5).

5. The molten salt energy storage system heating cable according to claim 1, characterized in that: The molten salt energy storage system heating cable further comprises a heat dissipation sleeve (3), the heat dissipation sleeve (3) being in the shape of a circular tube with openings at both ends, the heat dissipation sleeve (3) being provided with at least one heat insulation core (14) section at each end of the heating cable (1), the heat dissipation sleeve (3) wrapping the armor layer (13), and the two ends of the heat dissipation sleeve (3) being welded to the armor layer (13) as a whole.

6. A molten salt energy storage system heating cable according to claim 5, characterized in that: The outer sides of the two end surfaces of the heat dissipation sleeve (3) are chamfered.

7. The molten salt energy storage system heating cable according to claim 1, characterized in that: A heat shrink tube is also provided at the interface between the heating cable (1) and the power lead (2), and both ends of the heat shrink tube are located in the sealant (5).

8. The molten salt energy storage system heating cable according to claim 5, characterized in that: The heating cable further comprises an auxiliary component a (6) and an auxiliary component b (7), both of which are in the shape of a circular tube with openings at both ends. The auxiliary component a (6) and the auxiliary component b (7) are sleeved on the heating cable (1) between the sealing sleeve (4) and the heat dissipation sleeve (3), and the outer sides of the auxiliary component a (6) and the auxiliary component b (7) are both provided with a regular hexagonal tightening section; the inner hole of the auxiliary component a (6) comprises two parts, one end away from the auxiliary component b (7) is in contact with the armor layer (13), and the other end close to the auxiliary component b (7) is provided with a threaded hole, and the side of the auxiliary component b (7) close to the auxiliary component a (6) is provided with a corresponding external thread.

9. A molten salt energy storage system heating cable according to claim 8, characterized in that: The end of the auxiliary component b (7) away from the auxiliary component a (6) is also provided with a cap (8), and the cap (8) is connected to the auxiliary component b (7) by threads; or the end of the auxiliary component b (7) away from the auxiliary component a (6) is sealed with glue.

Images