Thermal-bridge-free thermal insulation pipe for first open area of geothermal well

Abstract

The utility model discloses a geothermal well first open area heat-bridge-free thermal insulation pipe which comprises a plurality of heat insulation pipes connected end to end, and every two adjacent heat insulation pipes are connected through a heat-bridge-free thermal insulation coupling. The heat insulation pipe comprises an outer sleeve and an inner sleeve, a heat insulation material is filled between the inner sleeve and the outer sleeve, the end of the inner sleeve and the end of the outer sleeve are connected in a sealed mode through a double-layer sealing rubber part, the heat-bridge-free heat preservation coupling comprises a coupling outer pipe, and a broken bridge rubber layer is arranged on the inner surface of the coupling outer pipe. The top end of the broken bridge rubber layer abuts against and makes contact with the double-layer sealing rubber part located on the upper portion, the bottom end of the broken bridge rubber layer abuts against and makes contact with the double-layer sealing rubber part located on the lower portion, the top end of the coupling outer pipe is in threaded connection with the outer sleeve located on the upper portion, and the bottom end of the coupling outer pipe is in threaded connection with the outer sleeve located on the lower portion. According to the thermal-bridge-free thermal insulation pipe, the interior and the exterior are completely isolated, it is guaranteed that no thermal bridge exists on the whole structure, and the heat conductivity coefficient and the heat loss are reduced.

Description

Technical Field

[0001] The utility model relates to the field of geothermal wells, in particular to a heat-bridge-free insulation pipe in an opening area of a geothermal well. Background Art

[0002] As a renewable energy source, geothermal energy has the advantages of wide distribution, low cost, easy mining, cleanliness and direct utilization. Vigorously promoting the use of geothermal energy is an effective measure for resource conservation and environmental protection, and is a way to achieve sustainable development of human society. At present, geothermal energy utilization technology is constantly developing and has become the best choice for building heating and cooling. The current geothermal technology is to drill holes into the rock and soil layer at a depth of 2000m to 4500m underground, insert an inner casing into the wall of the geothermal well pipe, and under the action of the heat exchanger, cold water enters deep into the geothermal well pipe wall, absorbs the underground high-temperature heat, and then flows upward from the bottom of the inner casing with thermal insulation, guiding the underground high-temperature heat to the heat exchanger, and heating the building through the heat exchanger, see Figure 5 .

[0003] At present, the inner casing used for geothermal well heat exchange mainly adopts insulated pipes, such as PE (polyethylene) pipes, PE-RT (heat-resistant polyethylene) pipes, PPH (homopolymer polypropylene) pipes and other non-metallic pipes. Although such pipes have a certain thermal insulation effect, their thermal insulation effect is poor. For the thermal insulation pipes in the low-temperature zone, better thermal insulation effect is required. At the same time, metal couplings are mainly used to connect the pipes. There are thermal bridges at the couplings, and the thermal conductivity coefficient at local positions is large, resulting in heat loss. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a heat-bridge-free thermal insulation pipe in an opening area of a geothermal well which has a low thermal conductivity and can significantly reduce heat loss.

[0005] In order to solve the above technical problems, the technical solution of the utility model is as follows: a heat-bridge-free insulation pipe in an opening area of a geothermal well is arranged in an opening wall pipe of the geothermal well, and the heat-bridge-free insulation pipe includes a plurality of heat-insulating pipes connected end to end, and adjacent two heat-insulating pipes are connected by a heat-bridge-free insulation coupling;

[0006] The thermal insulation pipe includes an outer sleeve and an inner sleeve concentrically arranged inside the outer sleeve, a thermal insulation cavity is formed between the inner sleeve and the outer sleeve, the thermal insulation cavity is filled with thermal insulation material, the inner sleeve and the ends of the outer sleeve are sealed by a double-layer sealing rubber member, and the inner surface of the inner sleeve and the outer surface of the outer sleeve are also coated with an epoxy powder anti-corrosion layer;

[0007] The thermal bridge-free insulation coupling includes a coupling outer tube, the inner surface of the coupling outer tube is provided with a thermal break rubber layer, the top end of the thermal break rubber layer is in contact with the double-layer sealing rubber part located above, and the bottom end of the thermal break rubber layer is in contact with the double-layer sealing rubber part located below, the top end of the coupling outer tube is threadedly connected to the outer sleeve above, and the bottom end of the coupling outer tube is threadedly connected to the outer sleeve below; the outer surface of the coupling outer tube is sleeved with an outer wall tube, and a coupling insulation cavity is formed between the coupling outer tube and the outer wall tube, and the coupling insulation cavity is filled with insulation material.

[0008] As a preferred technical solution, the double-layer sealing rubber part includes an inner annular sealing plate and an outer annular rubber plug. The inner annular sealing plate is sealed between the inner sleeve and the outer sleeve to seal the thermal insulation material. The outer annular rubber plug is squeezed and sealed between the inner sleeve and the outer sleeve. The inner end of the outer annular rubber plug contacts the inner annular sealing plate, and the outer end of the outer annular rubber plug is flush with the outer surface of the outer sleeve and contacts the end of the thermal break rubber layer.

[0009] As a preferred technical solution, the thermal break rubber layer is glued and fixed to the inner surface of the coupling outer tube, and the inner surface of the thermal break rubber layer is provided with an inner limiting shoulder that cooperates with the end of the inner sleeve.

[0010] As a preferred technical solution, the inner surface of the outer tube of the coupling is provided with an outer limiting shoulder that cooperates with the end of the outer sleeve, and the end of the thermal break rubber layer is flush with the end of the outer limiting shoulder.

[0011] Due to the adoption of the above-mentioned technical scheme, the beneficial effect of the utility model is that the thermal insulation pipe has a good thermal insulation effect, and is connected by a thermal bridge-free thermal insulation coupling. This thermal insulation pipe and the thermal bridge-free thermal insulation coupling are combined to form a thermal bridge-free thermal insulation pipe, which can significantly improve the thermal insulation and heat preservation effect, completely isolate the inside from the outside, ensure the existence of no thermal bridges in the overall structure, avoid heat short-circuit transfer between the external structure and the internal structure, and reduce thermal conductivity and heat loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0013] Figure 1 This is a diagram of the use state of an embodiment of the utility model;

[0014] Figure 2 It is a partial structural diagram of an embodiment of the utility model;

[0015] Figure 3This is a schematic structural diagram of a heat-insulating pipe according to an embodiment of the present invention;

[0016] Figure 4 This is a schematic structural diagram of a heat-insulating coupling without a thermal bridge according to an embodiment of the present invention;

[0017] Figure 5 is a schematic diagram of background technology;

[0018] In the figure: 100-geothermal well; 200-opening well wall pipe; 300-thermal insulation cementing layer; 400-thermal insulation pipe; 401-outer casing; 402-inner casing; 403-thermal insulation material; 404-inner annular sealing plate; 405-outer annular rubber plug; 500-thermal bridge-free insulation coupling; 501-coupling outer pipe; 502-broken bridge rubber layer; 503-outer wall pipe; 504-thermal insulation material; 505-inner limit shoulder; 506-outer limit shoulder; 507-protrusion. DETAILED DESCRIPTION

[0019] The present invention is further described below with reference to the accompanying drawings and examples. In the detailed description that follows, certain exemplary embodiments of the present invention are described by way of illustration only. It goes without saying that those skilled in the art will recognize that the described embodiments may be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the drawings and description are illustrative in nature and are not intended to limit the scope of the claims.

[0020] In a low-temperature zone of a geothermal well, the temperature of the geothermal well wall is relatively low, which can be as low as 15°C. When the high-temperature water after heat exchange flows upward through the insulation pipe, the low temperature from the geothermal well wall will exchange heat through the insulation pipe, resulting in heat loss inside the insulation pipe. Therefore, the utility model designs an insulation pipe for a low-temperature zone and provides a thermal bridge-free insulation pipe.

[0021] like Figure 1 and Figure 2 As shown, a thermal bridge-free insulated pipe in an open area of a geothermal well is arranged in an open well wall pipe 200 of a geothermal well 100. The thermal bridge-free insulated pipe comprises a plurality of end-to-end insulated pipes 400, and adjacent two thermal bridge-free insulated pipes 400 are connected by a thermal bridge-free insulated coupling 500. The thermal bridge-free insulated pipes 400 have good thermal insulation effects and are connected by the thermal bridge-free insulated coupling 500. The thermal bridge-free insulated pipes 400 and the thermal bridge-free insulated coupling 500 are combined to form a thermal bridge-free insulated pipe, which can significantly improve the thermal insulation and heat preservation effects, completely isolate the interior from the exterior, ensure the existence of thermal bridges in the overall structure, avoid the short-circuit transfer of heat between the external structure and the internal structure, and reduce the thermal conductivity and heat loss.

[0022] See also Figure 2 and Figure 3 The thermal insulation pipe 400 includes an outer sleeve 401 and an inner sleeve 402 concentrically arranged in the outer sleeve 401. A thermal insulation cavity is formed between the inner sleeve 402 and the outer sleeve 401. The thermal insulation cavity is filled with thermal insulation material 403. The inner sleeve 402 and the end of the outer sleeve 401 are sealed by a double-layer sealing rubber part. The double-layer sealing rubber part serves as a key component for sealing the thermal insulation cavity and is also a key component for achieving no thermal bridge.

[0023] In this embodiment, the outer casing 401 and the inner casing 402 can be made of stainless steel, N80 steel, or J55 steel. A thermal insulation material 403 is used between them to achieve good thermal insulation and heat preservation. The thermal insulation material 403 can be ultra-low thermal conductivity nano-lacquer gel, ceramic fiber thermal insulation material 403, vacuum, inert gas, etc. This stainless steel pipe used as the inner casing 402 of the geothermal well 100 has good strength, better bending load resistance, and is relatively low in price.

[0024] The double-layer sealing rubber component includes an inner annular sealing plate 404 and an outer annular rubber plug 405. The inner annular sealing plate 404 is sealed between the inner sleeve 402 and the outer sleeve 401 to seal the thermal insulation material 403. The outer annular rubber plug 405 is squeezed and sealed between the inner sleeve 402 and the outer sleeve 401. The inner end of the outer annular rubber plug 405 contacts the inner annular sealing plate 404, and the outer end of the outer annular rubber plug 405 is flush with the outer surface of the outer sleeve 401 and contacts the end of the thermal break rubber layer. The inner annular sealing plate 404 can be made of a hard rubber plate, which has a good sealing effect and is used to ensure the stable sealing of the internal thermal insulation material 403. The sealing plate can first be installed between the inner sleeve 402 and the outer sleeve 401 by gluing, and the sealing is achieved by the glue layer. In order to further ensure the installation stability, an outer annular rubber plug 405 is added to the outer annular sealing plate 404. The outer annular rubber plug 405 can be squeezed and inserted between the outer sleeve 401 and the inner sleeve 402 by gluing or heat processing. On the one hand, it serves as a second sealing layer to ensure the stable sealing of the thermal insulation material 403. On the other hand, it serves as a key structure for no thermal bridge. The outer end of the outer annular rubber plug 405 is connected to the thermal bridge rubber layer of the thermal bridge-free insulation coupling 500, which can completely isolate the internal structure from the external structure and ensure the existence of no thermal bridge in the overall structure. The outer annular rubber plug 405 is made of a rubber material with a low thermal conductivity coefficient.

[0025] See also Figure 2 and Figure 4The thermal bridge-free insulation coupling 500 includes a coupling outer tube 501, and the inner surface of the coupling outer tube 501 is provided with a thermal break rubber layer 502. The top end of the thermal break rubber layer 502 is in contact with the outer annular rubber plug 405 located above, and the bottom end of the thermal break rubber layer 502 is in contact with the outer annular rubber plug 405 located below. The top end of the coupling outer tube 501 is threadedly connected to the outer sleeve 401 above, and the bottom end of the coupling outer tube 501 is threadedly connected to the outer sleeve 401 below. By adding a thermal break rubber layer 502 to the inner surface of the coupling outer tube 501, the top and bottom ends of the thermal break rubber layer 502 are used to dock with the corresponding outer annular rubber plug 405, so that the thermal insulation material 403, the inner annular sealing plate 404, the outer annular rubber plug 405, the thermal break rubber layer 502, the outer annular rubber plug 405, the inner annular sealing plate 404, and the thermal insulation material 403 cooperate to form a contact-type thermal bridge-free structure for completely isolating the interior from the exterior. The thermal break rubber layer 502 is made of a rubber material with a low thermal conductivity coefficient.

[0026] The coupling outer tube 501 can be a metal tube, which is connected to the outer sleeve 401 by a thread, but the heat is isolated inside by a broken bridge rubber layer 502. In order to further improve the thermal insulation effect of the coupling outer tube 501, an outer wall tube 503 is provided on the outer surface of the coupling outer tube 501, and a coupling insulation cavity is formed between the coupling outer tube 501 and the outer wall tube 503. The coupling insulation cavity is filled with insulation material 504. The insulation material 504 can be nano-paint gel with ultra-low thermal conductivity or ceramic fiber insulation material. The coupling insulation cavity can be sealed by a rubber plug or a metal plate.

[0027] The thermal break rubber layer 502 is glued and fixed to the inner surface of the outer tube 501 of the coupling. The inner surface of the thermal break rubber layer 502 is provided with an inner limit shoulder 505 that cooperates with the end of the inner sleeve 402. The inner limit shoulder 505 serves as a limiting structure. The end of the inner sleeve 402 exceeds the outer sleeve 401 by a certain distance, so that the bottom end of the inner sleeve 402 can just rest on the inner limit shoulder 505. On the one hand, it serves as a limiting structure of the thermal insulation pipe 400. On the other hand, the upper and lower inner sleeves 402 squeeze the inner limit shoulder 505 at the same time, which can limit the position of the inner limit shoulder 505 to prevent it from loosening and displacement.

[0028] The inner surface of the coupling outer tube 501 is provided with an outer limiting shoulder 506 that cooperates with the end of the outer sleeve 401, and the end of the thermal break rubber layer 502 is flush with the end of the outer limiting shoulder 506, that is, when the end of the thermal break rubber layer 502 contacts the outer annular rubber plug 405, the end of the outer sleeve 401 also just contacts the outer limiting shoulder 506 and the outer annular rubber plug 405.

[0029] The top and bottom surfaces of the thermal break rubber layer 502 that are in contact with the outer annular rubber plug 405 are both provided with protrusions 507. Since the rubber material has a certain elasticity, when it is fully installed in place, the corresponding outer annular rubber plug 405 will squeeze the protrusion 507 and deform it, thereby ensuring stable contact between the outer annular rubber plug 405 and the thermal break rubber layer 502.

[0030] The inner surface of the inner sleeve 402 and the outer surface of the outer sleeve 401 are both coated with an epoxy powder anti-corrosion layer to improve corrosion resistance.

[0031] A thermal insulation cementing layer 300 is provided between the outer wall of the well wall pipe 200 and the inner wall of the geothermal well 100. The thermal insulation cementing layer 300 is a rubber powder foam particle slurry layer. The rubber powder foam particle slurry layer is composed of a mixture of mud and rubber powder polystyrene particles, so that the cementing layer not only has a good solidification effect, but also has a good thermal insulation effect, which can effectively block the low temperature of the geothermal well 100, serving as another effective measure to improve the thermal insulation effect of the insulation pipe.

[0032] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements are intended to fall within the scope of the present invention. The scope of protection claimed in this invention is defined by the appended claims and their equivalents.

Claims

1. A heat-bridge-free insulation pipe in an opening area of a geothermal well is installed in a wall pipe of an opening of a geothermal well, and is characterized by: The thermal bridge-free insulation pipe comprises a plurality of thermal insulation pipes connected end to end, and two adjacent thermal insulation pipes are connected via a thermal bridge-free insulation coupling; The thermal insulation pipe includes an outer sleeve and an inner sleeve concentrically arranged inside the outer sleeve, a thermal insulation cavity is formed between the inner sleeve and the outer sleeve, the thermal insulation cavity is filled with thermal insulation material, the inner sleeve and the ends of the outer sleeve are sealed by a double-layer sealing rubber member, and the inner surface of the inner sleeve and the outer surface of the outer sleeve are also coated with an epoxy powder anti-corrosion layer; The thermal bridge-free insulation coupling includes a coupling outer tube, the inner surface of the coupling outer tube is provided with a thermal break rubber layer, the top end of the thermal break rubber layer is in contact with the double-layer sealing rubber part located above, and the bottom end of the thermal break rubber layer is in contact with the double-layer sealing rubber part located below, the top end of the coupling outer tube is threadedly connected to the outer sleeve above, and the bottom end of the coupling outer tube is threadedly connected to the outer sleeve below; the outer surface of the coupling outer tube is sleeved with an outer wall tube, and a coupling insulation cavity is formed between the coupling outer tube and the outer wall tube, and the coupling insulation cavity is filled with insulation material.

2. The geothermal well opening zone heat bridge-free insulation pipe according to claim 1, characterized in that: The double-layer sealing rubber component includes an inner annular sealing plate and an outer annular rubber plug. The inner annular sealing plate is sealed between the inner sleeve and the outer sleeve to seal the thermal insulation material. The outer annular rubber plug is squeezed and sealed between the inner sleeve and the outer sleeve. The inner end of the outer annular rubber plug contacts the inner annular sealing plate, and the outer end of the outer annular rubber plug is flush with the outer surface of the outer sleeve and contacts the end of the thermal break rubber layer.

3. The geothermal well opening zone heat bridge-free insulation pipe according to claim 1, characterized in that: The thermal break rubber layer is glued and fixed to the inner surface of the outer tube of the coupling, and the inner surface of the thermal break rubber layer is provided with an inner limiting shoulder matched with the end of the inner sleeve.

4. The geothermal well opening zone heat-bridge-free insulation pipe according to claim 1, characterized in that: The inner surface of the outer tube of the coupling is provided with an outer limiting shoulder matched with the end of the outer sleeve, and the end of the thermal break rubber layer is flush with the end of the outer limiting shoulder.

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