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CN-224214974-U - Small-caliber central heat preservation pipe for middle-deep geothermal well

CN224214974UCN 224214974 UCN224214974 UCN 224214974UCN-224214974-U

Abstract

The utility model discloses a small-caliber central heat-insulating pipe for a middle-deep geothermal well, which comprises an inner pipe and an outer pipe, wherein two ends of the inner pipe and two ends of the outer pipe are connected in an annular mode to form a sealed cavity, a heat-insulating layer wrapping the inner pipe is arranged in the sealed cavity, the heat-insulating layer is of a layered structure, a BOPET film is used as a base material, and an aluminum film is electroplated on the BOPET film. The BOPET film substrate and the electroplated aluminum film are combined, so that the reflection performance of the heat preservation layer is enhanced, the outward heat transfer of internal heat is effectively prevented, the light weight and high strength of the heat preservation layer are ensured, the structure is compact and smooth, and the coating is convenient. The strip-shaped rib design not only increases the strength of the cladding, prevents deformation or breakage of the heat insulation layer in long-time use, but also can be used as a datum line of cladding, ensures alignment of axes during cladding, reduces dislocation of the heat insulation layer at the interface, ensures flatness, improves heat reflectivity and heat insulation effect, facilitates accurate positioning of constructors, and improves construction efficiency.

Inventors

  • XU FANGJUN
  • CHEN QIANLONG
  • MA ZHI

Assignees

  • 西安润威恒泰地热管技术有限公司

Dates

Publication Date
20260508
Application Date
20250625

Claims (6)

  1. 1. The utility model provides a well deep geothermal well is with small-bore central insulating tube, its characterized in that includes inner tube (1) and outer tube (2), sealed cavity is formed at inner tube (1) and outer tube (2) both ends annular connection, set up heat preservation (3) of parcel inner tube in the sealed cavity, heat preservation (3) are layered structure, adopt BOPET film (3-1) to do the substrate, electroplate one deck aluminium film (3-2) on the BOPET film.
  2. 2. The small-caliber central heat preservation pipe for the middle-deep geothermal well according to claim 1 is characterized in that the heat preservation layer (3) is of a cuboid structure, and strip-shaped ribs (4) are respectively arranged on two long sides of the heat preservation layer (3).
  3. 3. The small-caliber central heat preservation pipe for the middle-deep geothermal well according to claim 2, wherein the strip-shaped ribs (4) are sewn on two long sides of the heat preservation layer (3) respectively by fine wires, and the fine wires are made of inorganic materials.
  4. 4. The small-caliber central heat preservation pipe for the middle-deep geothermal well according to claim 1 is characterized in that a plurality of binding bands (5) are arranged on an aluminum film (3-2) of the heat preservation layer (3).
  5. 5. The small-caliber central heat preservation pipe for the middle-deep geothermal well according to claim 4, wherein the axis of the binding bands (5) is perpendicular to the axis of the heat preservation layer (3), and the interval between the binding bands (5) is 0.8-1.2 m.
  6. 6. The small-caliber central heat preservation pipe for the middle-deep geothermal well is characterized in that the inner pipe (1) and the outer pipe (2) are concentric carbon steel pipes, the length of the outer pipe (2) is larger than that of the inner pipe (1), the outer diameter of the inner pipe (1) is smaller than that of the outer pipe (2), two ends of the inner pipe (1) and two ends of the outer pipe (2) are welded in an annular mode to form a sealed cavity, and the sealed cavity is vacuumized.

Description

Small-caliber central heat preservation pipe for middle-deep geothermal well Technical Field The utility model belongs to the field of central heat preservation pipes, and particularly relates to a small-caliber central heat preservation pipe for a middle-deep geothermal well. Background The small-caliber geothermal central heat-insulating pipe is a central pipe for geothermal wells, the outer diameter of which is less than or equal to 100mm, is used for underground pipe columns of geothermal wells, and is used for conveying underground green heat sources deep in stratum to the ground and is generally applied to the fields of geothermal resource development, petroleum exploitation and the like. The traditional small-caliber heat-insulating pipe is produced by adopting a one-step method, the steel pipe and the outer protective pipe are coaxially fixed, the polyurethane foaming material is injected into the middle of the pipe for one-step molding, and the production efficiency of the process is high. However, the small-caliber pipeline has small outer diameter, the thickness of the heat preservation layer is usually thinner (for example, the thickness of the heat preservation layer of the DN100 pipeline is 30-50 mm), so that the thermal resistance is smaller, and polyurethane foam (the temperature resistance is less than or equal to 120 ℃) is adopted, if the polyurethane foam is used for conveying geothermal fluid or steam with the temperature of more than 120 ℃, the foam can be gradually carbonized and contracted, so that the heat preservation layer is separated from the inner pipe, and an air layer is formed, so that the heat loss is suddenly increased. Meanwhile, the small-caliber pipeline is dense in interface, the heat insulation layers are required to be processed section by section during welding or hot melting connection, the labor cost is high, and the tightness is not easy to guarantee. Disclosure of utility model In order to overcome the defects of the prior art, the utility model aims to provide the small-caliber central heat preservation pipe for the middle-deep geothermal well, and solve the problems of high heat loss, limited applicable temperature, difficult manufacture and unchanged installation of the traditional small-caliber central heat preservation pipe. The utility model is realized by the following technical scheme: The utility model provides a well deep geothermal well is with small-bore center insulating tube, includes inner tube and outer tube, inner tube and outer tube both ends annular connect and form sealed cavity, set up the heat preservation of parcel inner tube in the sealed cavity, the heat preservation is the lamellar structure, adopts BOPET film to take the substrate, electroplate one deck aluminium film on the BOPET film. Further, the heat preservation is the cuboid structure, and two long limits of heat preservation set up the strip muscle respectively. Further, the strip-shaped ribs are respectively sewn on two long sides of the heat preservation layer by thin lines, and the thin lines are made of inorganic materials. Further, a plurality of binding belts are arranged on the aluminum film of the heat preservation layer. Further, the axis of the binding belts is perpendicular to the axis of the heat insulation layer, and the interval between the binding belts is 0.8-1.2 meters. Further, the inner tube and the outer tube are concentric carbon steel tubes, the length of the outer tube is larger than that of the inner tube, the outer diameter of the inner tube is smaller than that of the outer tube, two ends of the inner tube and two ends of the outer tube are welded in an annular mode to form a sealed cavity, and the sealed cavity is vacuumized. Compared with the prior art, the utility model has the following beneficial effects: The BOPET film substrate and the electroplated aluminum film are combined, so that the reflection performance of the heat preservation layer is enhanced, the outward heat transfer of internal heat is effectively prevented, the light weight and high strength of the heat preservation layer are ensured, the structure is compact and smooth, and the coating is convenient. The design of the strip-shaped ribs not only increases the strength of the coating and prevents the thermal insulation layer from deforming or being damaged in long-time use, but also can be used as a datum line of the coating, ensures the alignment of axes in the coating process, reduces the dislocation of the thermal insulation layer at the interface, ensures flatness, improves the heat reflectivity and the thermal insulation effect, is convenient for constructors to accurately position, and improves the construction efficiency. The band disclosed by the utility model is convenient to construct and bind, and the working efficiency is improved. Drawings Fig. 1 is a schematic cross-sectional view of the present utility model. FIG. 2 is a schematic view of the heat insulation layer stru