JP5584839B1 - Hybrid spiral pile with integrated underground heat collection function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ground heat collection function integrated hybrid spiral pile capable of efficiently collecting ground heat without impairing the function as a spiral pile.
SOLUTION: A heat exchanging hollow tube 2 embedded in the ground and through which a heat exchanging liquid or ground water flows, the heat exchanging hollow tube 2 having a spiral shape with the same radius and the same pitch. The tip is formed with a sharp tip. In addition, an interior tube 3 that is spirally formed along the heat exchange hollow tube 2 to the vicinity of the tip is provided inside the heat exchange hollow tube 2. A circulation port 31 that can circulate with the inside of the heat exchange hollow tube 2 may be formed in the vicinity.
[Selection] Figure 1

Description

  The present invention relates to a ground pile for supporting a structure such as a greenhouse and a hybrid spiral pile with an integrated underground heat collection function having a collection function for underground heat.

  The structure is supported by foundation piles buried in the ground to protect it from collapse due to ground subsidence or storms.

  On the other hand, the temperature in the ground where foundation piles are buried is constant throughout the year. Therefore, in winter, it is kept at a temperature higher than the temperature, and in summer it is kept at a temperature lower than the temperature. Unlike the fossil fuel, this geothermal energy is infinite and will not be depleted. .

  Therefore, conventionally, proposals have been made to use a foundation pile buried in the ground not only as a foundation pile for supporting a structure but also as a heat collector for collecting underground heat.

  For example, in Japanese Patent Application Laid-Open No. 2013-124441, a hollow ready-made concrete pile having an annular metal end plate at an end portion, having an exchange pipe provided in a U shape in the pile body, Proposed ready-made concrete pile for use in underground heat, characterized in that it is provided with a heat conductor with better thermal conductivity than concrete extending along the pile axis direction and its end is joined to the end plate (Patent Document 1). According to the ready-made concrete pile described in Patent Document 1, the heat transfer to the exchange pipe is promoted by the heat conductor, so that the efficiency of heat exchange with the ground can be increased.

JP 2013-124441 A

  However, it is necessary to widen the foundation width or the foundation depth of the concrete foundation of the old construction method in order to cope with the heavy pressure of the superstructure. However, there is a problem that a large site area is required to widen the foundation width. Moreover, in order to deepen a foundation depth, it is necessary to cut a deep hole. Therefore, any method has technical and economic limitations.

  Moreover, in the invention described in Patent Document 1, since the heat exchange pipe and the ground are not in direct contact with each other, there is a problem that the heat exchange performance by the heat conductor has a limit in the heat exchange efficiency. Therefore, in order to perform sufficient heat exchange, the foundation depth must be deepened.

  Furthermore, when concrete foundations are buried in the ground, there is a problem that they cannot be taken out easily, which is not suitable as a foundation for a simple structure such as a plastic house.

  For these problems, a spiral pile formed in a spiral shape may be used instead of a concrete pile. Spiral piles are installed by screwing into the ground by the action of rotational force and compressive force, and can easily cope with the heavy pressure of structures depending on the thickness of the pile, the size of the spiral diameter, and the screwing depth. It is something that can be done. That is, the spiral pile has an advantage that the foundation depth can be easily increased without reducing the site area.

  However, the conventional spiral pile does not have a function capable of collecting underground heat. In particular, the thickness of the spiral pile cannot be made too thick considering the ease of screwing into the ground. Therefore, there is a problem that a space for installing a U-shaped heat exchange pipe in the pile body cannot be taken as in a conventional concrete pile.

  The present invention has been made in order to solve such problems, and it is possible to efficiently collect ground heat without impairing the function as a spiral pile. It aims to provide a body-type hybrid spiral pile.

  A ground heat collection function-integrated hybrid spiral pile according to the present invention is a heat exchange hollow tube that is buried in the ground and allows a heat exchange liquid or groundwater to flow therethrough. The tube is formed in a spiral shape having the same radius and the same pitch, and its tip is formed in a sharp shape.

  Further, as one aspect of the present invention, an interior tube formed in a spiral shape up to the vicinity of the tip along the heat exchange hollow tube is provided inside the heat exchange hollow tube. In the vicinity of the tip of the tube, a circulation port that can circulate with the inside of the heat exchange hollow tube may be formed.

  Furthermore, as one aspect of the present invention, the inner tube may be formed of a soft material in a tube having an outer diameter smaller than the inner diameter of the heat exchange hollow tube.

  In addition, as one aspect of the present invention, a base portion of the heat exchange hollow tube that is in communication with the heat exchange hollow tube and into which the interior tube is inserted, and the interior tube A perforated lid that is screwed into the base part while inserting and holding, and a water leakage preventing rubber that retains water tightness with the interior pipe by reducing the diameter by pressing when the perforated lid is screwed into the base part You may have a ring.

  Furthermore, as one aspect of the present invention, two hollow tubes for heat exchange are arranged in close contact with each other, and at each end, a circulation port is formed that enables the flow between each other. May be.

  Further, as one aspect of the present invention, a plurality of strainers that allow inflow or outflow of groundwater may be provided in the vicinity of the tip of the heat exchange hollow tube.

  According to the present invention, it is possible to efficiently collect underground heat without impairing the function as a spiral pile.

It is a figure which shows 1st embodiment of the underground heat collection function integrated hybrid spiral pile which concerns on this invention, and a heating system using the same. It is a partial sectional view showing the inside of the heat exchange hollow tube in the first embodiment. It is sectional drawing which shows a nozzle | cap | die part, a perforated lid, and a water leakage prevention rubber ring provided in the base end part of the hollow tube for heat exchange in this 1st embodiment. It is an exploded view which shows a nozzle | cap | die part in this 1st embodiment, a perforated lid, and a water leak prevention rubber ring. It is a figure which shows the circulation of the heat exchange liquid in this 1st embodiment. It is sectional drawing which shows the flow of the heat exchange liquid of the hollow tube for heat exchange in this 1st embodiment, and the image of underground heat. It is a figure which shows the flow of the heat exchange liquid according to the second embodiment of the underground heat collection function-integrated hybrid spiral pile and the heating system using the same according to the present invention. It is sectional drawing which shows the flow of the heat exchange liquid at the front-end | tip of the hollow tube for heat exchange in this 2nd embodiment, and the image of underground heat. It is a figure which shows the flow of groundwater and 3rd embodiment of the underground heat collection function integrated hybrid spiral pile and heating system using the same according to the present invention.

  Hereinafter, a first embodiment of the underground heat collection function-integrated hybrid spiral pile according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1 to FIG. 3, the underground heat collection function-integrated hybrid spiral pile 1a of the first embodiment includes a heat exchange hollow tube 2 formed in a spiral shape and the heat exchange hollow tube 1a. And an interior pipe 3 provided inside the empty pipe 2. Moreover, the underground heat collection function integrated hybrid spiral pile 1a of the first embodiment is connected to a heat exchange liquid circulation device 4 that circulates the heat exchange liquid, as shown in FIG. Hereinafter, each configuration will be described in detail.

  The heat exchange hollow tube 2 is a hollow tube buried in the ground, and a heat exchange liquid or groundwater can be circulated therein. That is, the heat exchanging hollow tube 2 heats the heat exchanging liquid by collecting heat from the underground or pumps up groundwater heated by the underground heat. The heat exchange hollow tube 2 in the first embodiment collects ground heat by circulating a heat exchange liquid.

  The shape of the heat exchange hollow tube 2 is formed in a spiral shape having the same radius and the same pitch. Thereby, when the hollow tube 2 for heat exchange is screwed into the ground or removed from the ground, friction with the ground is suppressed by passing through the same trajectory. Moreover, the front-end | tip of the hollow tube 2 for heat exchange is formed in the acute shape, and the resistance from the earth and sand etc. when screwed in in the ground is reduced. That is, the heat exchange hollow tube 2 is formed in a shape that can be easily embedded in the ground and easily removed.

  In addition, the material of the heat exchange hollow tube 2 has high heat conductivity and heat transfer coefficient between the ground and the circulating water to be circulated in order to easily collect the ground heat into the circulating heat exchange liquid. Higher one is desirable. Moreover, since the hollow tube 2 for heat exchange is used as a foundation, it requires strength to prevent damage or the like during and after embedding. Therefore, in the first embodiment, a metal such as cast iron is used as the material of the heat exchange hollow tube 2, but it is not particularly limited as long as the same effect is obtained.

  In addition, an interior tube 3 made of a soft material is provided inside the hollow tube 2 for heat exchange in the first embodiment, as will be described later. On the other hand, the hollow tube 2 for heat exchange needs to support the structure A on the upper part thereof, and thus cannot be configured to insert the inner tube 3 from the upper part. Therefore, on the base end side of the heat exchange hollow tube 2 in the first embodiment, as shown in FIGS. 3 and 4, a base part 21 for inserting the interior pipe 3 therein, and this base part A perforated lid 22 that closes 21 and a water leakage preventing rubber ring 23 that maintains water tightness between the interior pipe 3 and the base part 21 are provided.

  As shown in FIG. 4, the base portion 21 is a hole that communicates the inside and the outside of the heat exchange hollow tube 2, and is formed to have a dimension that allows the interior tube 3 to be inserted. Further, the base portion 21 protrudes to the outside of the heat exchange hollow tube 2, and a groove 24 into which the water leakage preventing rubber ring 23 is inserted is formed. Further, a male screw 25 is formed on the outer peripheral surface, and the perforated lid 22 is screwed.

  The perforated lid 22 is a lid of the base part 21, and has a hole through which the inner pipe 2 can be inserted in communication with a hole provided in the base part 21. On the base end side of the perforated lid 22, a groove 26 into which the water leakage preventing rubber ring 23 is inserted is formed in the same manner as the base portion 21. A female screw 27 that is screwed into the male screw 25 of the base 21 is formed on the inner peripheral surface of the groove 26.

  The water leakage preventing rubber ring 23 is for maintaining watertightness with the interior pipe 3, and is provided with a hole through which the interior pipe 3 is inserted. Further, the water leakage preventing rubber ring 23 is formed to have a size that allows a gap to be formed between the inner pipe 3 and between the groove 24 of the base part 21 and the groove 26 of the perforated lid 22. It is formed in a dimension longer than the depth of the groove 21 of 21. Thereby, as shown in FIG. 3, the water leakage preventing rubber ring 23 is reduced in diameter by pressing when the perforated lid 22 is screwed into the base part 21, and the water leakage prevention rubber ring 23 is formed between the base part 21 and the interior pipe 3. It is designed to maintain watertightness.

  Note that the structure in which the inner tube 3 is inserted into the heat exchange hollow tube 2 is not limited to the one using the cap 21 or the like, and may be appropriately changed as long as the same effect is obtained.

  As shown in FIG. 2 and FIG. 3, the inner tube 3 is provided inside the heat exchange hollow tube 2 to form a double tube structure together with the heat exchange hollow tube 2. That is, a continuous distribution path from the ground to the ground and from the ground to the ground is formed by making the inner tube 3 and the heat exchange hollow tube 2 have a double tube structure. Thereby, it is not necessary to form a U-shaped structure such as a heat exchange pipe inside the heat exchange hollow tube 2, and the heat exchange hollow tube 2 can be formed thin.

  The inner tube 3 is spirally formed along the heat exchanging hollow tube 2 to the vicinity of the tip, and in the vicinity of the tip of the inner tube 3, a circulation port 31 that can circulate with the inside of the heat exchanging hollow tube 2. Is formed. As a result, the heat exchange liquid can be circulated deeply into the ground that is not easily affected by the temperature of the ground.

  Further, the inner tube 3 in the first embodiment is formed of a soft material having an outer diameter smaller than the inner diameter of the heat exchange hollow tube 2. That is, the inner tube 3 can be easily formed into a double tube structure by being inserted from the base end side of the heat exchange hollow tube 2. The soft material used for the interior pipe 3 is not particularly limited and can be appropriately selected. Examples thereof include vinyl chloride, silicon, synthetic rubber, and natural rubber.

  Next, the heat exchange liquid circulation device 4 connected to the underground heat collection function-integrated hybrid spiral pile 1a will be described. As shown in FIG. 1, the heat exchange liquid circulation device 4 includes a pump 41 for circulating the heat exchange liquid and a heat exchange means 42 for performing heat exchange with the heat exchange liquid.

  The pump 41 is connected to the internal pipe 3 and supplies heat exchange liquid to the internal pipe 3. The type of the pump 41 is not particularly limited, and is appropriately selected from a turbo pump and a volumetric pump.

  The heat exchanging means 42 exchanges the heat of the heat exchange liquid with heat used for snow melting, heating, cooling, or the like. The heat exchanging means 42 in the first embodiment is a heating pump for heating the structure A. The heat exchanging means 42 efficiently extracts the heat of the heat exchange liquid that passes through the structure A and supplies it to the structure A.

  In addition, although the pump 41 and the heat exchange means 42 are separate bodies, they may be integrally formed. The heat exchanging means 42 is not limited to a heating heat pump, and may be for cooling or a radiator or the like.

  Next, the effect | action of each structure in the underground heat collection function integrated hybrid spiral pile 1a of this 1st embodiment is demonstrated.

  First, the pile function of the underground heat collection function-integrated hybrid spiral pile 1a will be described. As shown in FIG. 1, the underground heat collection function-integrated hybrid spiral pile 1 a is embedded in the ground to serve as the foundation of the structure A. In this first embodiment, it can be embedded in the ground by screwing into the ground from the tip side while applying rotation and pressure. The heat exchanging hollow tube 2 has a low resistance because it advances so as to push the earth and sand in the ground by the sharply formed tip.

  Further, since the heat exchange hollow tubes 2 are formed with the same radius and the same pitch, the resistance is low because the heat exchange hollow tubes 2 are embedded along the trajectory formed by the tip. Moreover, since sufficient proof stress for supporting a structure can be obtained according to the depth to embed, the installation area does not change with respect to the structure A, and the site area can be used effectively. it can.

  The underground heat collecting function-integrated hybrid spiral pile 1a is not limited to being embedded by screwing. For example, a ground hole is integrated into the underground heat collecting function-integrated hybrid spiral pile. You may make it embed by installing 1a and throwing in earth and sand.

  The buried underground heat collecting function-integrated hybrid spiral pile 1a can be taken out of the ground by rotating in the direction opposite to the screwed direction. Since the heat exchange hollow tubes 2 formed with the same radius and the same pitch rotate along the locus of the formed holes, they can be taken out with a small resistance. Thus, since the underground heat collecting function-integrated hybrid spiral pile 1a can be easily taken out from the ground, it can be easily transferred and reused, and the cost at that time can be reduced. Therefore, it is applicable also to the foundation of simple structures A, such as a greenhouse.

  Next, the function of collecting the underground heat of the underground heat collecting function-integrated hybrid spiral pile 1a will be described. In the buried underground heat collection function-integrated hybrid spiral pile 1a, the heat exchange liquid is circulated to heat the heat exchange liquid by the underground heat transmitted through the heat exchange hollow tube 2. ·Cooling.

  Specifically, as shown in FIG. 5, a heat exchange liquid is supplied to the interior pipe 3 by a pump 41. The supplied heat exchange liquid passes through the inside of the interior pipe 3, and is sent to the heat exchange hollow pipe 2 from a flow port 31 provided near the tip, as shown in FIG. The heat exchange liquid in the heat exchange hollow tube 2 rises from the distal end side to the proximal end side by the water pressure by the pump 41.

  The hollow tube for heat exchange 2 collects ground heat in the process of rising and warms the heat exchange liquid. Since the heat exchange hollow tube 2 and the underground are in direct contact with each other, the underground heat is easily transmitted. Moreover, since the hollow tube 2 for heat exchange is formed in a spiral shape, the contact area with the ground is large with respect to the depth and area embedded therein. Therefore, in the heat exchange hollow tube 2, the underground heat can be efficiently collected.

  The warmed heat exchange liquid rises and is sent to the heat exchange means 42. In the first embodiment, the heat is sent to the heat pump, and the heat pump extracts heat from the heat exchange liquid and is used for heating the structure A.

  In addition, at the base end portion of the heat exchange hollow tube 2, the water tightness of the water leakage preventing rubber ring 23, which has been reduced in diameter by the cap portion 21 and the perforated lid 22, and the interior tube 3 is maintained. That is, the heat exchange liquid can be circulated without decreasing. Therefore, in the underground heat collection function-integrated hybrid spiral pile 1a of the first embodiment, it is not necessary to replenish the heat exchange liquid and the running cost can be suppressed.

  The heat exchange liquid can be circulated in the reverse direction. That is, the heat exchange liquid is supplied from the proximal end side of the heat exchange hollow tube 2 and flows to the distal end side. The hollow tube for heat exchange 2 collects ground heat in this distribution process and warms the heat exchange liquid. The warmed heat exchange liquid is circulated from the distribution port 31 to the interior pipe 3 and pumped up. The pumped heat exchange liquid is sent to the heat exchanging means 41 to use the underground heat. Thus, the underground heat collecting function-integrated hybrid spiral pile 1a in the first embodiment can collect the underground heat even if the heat exchange liquid is circulated in the reverse direction.

According to the underground heat collection function-integrated hybrid spiral pile 1a of the first embodiment as described above, the following effects can be obtained.
1. It can function as a heat collecting tube that collects underground heat without impairing the original function of the spiral pile as the foundation of the structure A.
2. Since a heat exchange pipe is not required in the heat exchange hollow tube 2, it can be formed thin, and the force required for screwing can be reduced.
3. By forming a spiral with the same radius and the same pitch, not only embedding but also removal from the ground becomes easy, and it can be relocated and reused.
4). Since the contact area with the ground is larger than the installation area, heat can be collected efficiently.

  Next, a second embodiment of the underground heat collection function-integrated hybrid spiral pile according to the present invention will be described with reference to the drawings. In addition, about the structure which is equivalent to the structure of 1st embodiment mentioned above among the underground heat collection function integrated hybrid spiral pile 1b of this 2nd embodiment, description for the second time is abbreviate | omitted.

  The feature of the hybrid spiral pile 1b with an integrated underground heat collection function of the second embodiment is that, in the configuration of the first embodiment, two internal tubes 3 are not provided, and two heat exchange hollow tubes 2 are in close contact with each other. The point is that they are arranged side by side. Details will be described below.

  As shown in FIG. 7, the heat exchange hollow tube 2 according to the second embodiment includes a first heat exchange hollow tube 2a and a second heat exchange hollow tube 2b. The first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b are juxtaposed in close contact with each other and are formed so as not to become thick.

  Further, the tip is formed to be sharp with the first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b being in close contact with each other. Therefore, the first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b function as one spiral pile.

  Further, as shown in FIG. 8, a flow port 28 is formed at the tip of each of the first heat exchange hollow tube 2 a and the second heat exchange hollow tube 2 b so as to allow mutual flow between the insides. Has been. Thereby, one heat exchange hollow tube 2 functions as the interior tube 3 in the first embodiment, and the other heat exchange hollow tube 2 functions as the heat exchange hollow tube 2 in the first embodiment. . Hereinafter, the operation of the first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b in the second embodiment will be described.

  First, the pile function is the same as in the first embodiment. That is, as described above, the first heat exchanging hollow tube 2a and the second heat exchanging hollow tube 2b are integrated into one spiral pile. It can be buried in the ground by screwing it into the ground. Also, when moving, it can be removed from the ground if it rotates in the reverse direction.

  On the other hand, the heat collection function is different from the first embodiment. The first heat exchange hollow tube 2a in the second embodiment functions as the inner tube 3 in the first embodiment. Specifically, as shown in FIG. 7, the heat exchange liquid is supplied to the first heat exchange hollow tube 2a. As shown in FIG. 8, the supplied heat exchange liquid is circulated to the second heat exchange hollow tube 2 b via the circulation port 28. However, the first heat exchanging hollow tube 2a can heat or cool the heat exchanging liquid that collects and distributes the underground heat.

  The heat exchange liquid warmed by the first heat exchange hollow tube 2a flows into the second heat exchange hollow tube 2b. And like the hollow tube 2 for heat exchange of 1st embodiment, ground heat can be obtained even while it distribute | circulates from the front end side to the base end side.

  Further, since the first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b are in close contact with each other, heat exchange can also be performed through the boundary.

  From the above, according to the underground heat collection function-integrated hybrid spiral pile 1b of the second embodiment, the ground heat is generated in both the first heat exchange hollow tube 2a and the second heat exchange hollow tube 2b. The heat can be collected, and an efficient heat collection effect can be expected.

  Next, a third embodiment of the underground heat collection function-integrated hybrid spiral pile according to the present invention will be described with reference to the drawings. In addition, about the structure which is equivalent to the structure of 1st embodiment mentioned above and 2nd embodiment among the underground heat collection function integrated hybrid spiral pile 1c of this 3rd embodiment, description is abbreviate | omitted again. To do.

  The feature of the hybrid spiral pile 1c with an integrated underground heat collection function according to the third embodiment is that a plurality of strainers 29 are provided in the vicinity of the tip of the heat exchange hollow tube 2. Details will be described below.

  As shown in FIG. 9, the heat exchange hollow tube 2 in the third embodiment is provided with a plurality of strainers 29. The strainer 29 is a hole through which groundwater can be taken into the heat exchange hollow tube 2 from the ground, and has a filter or the like for preventing inflow of earth and sand. These strainers 29 are provided in the vicinity of the tip of the heat exchanging hollow tube 2 so that groundwater can be taken from a deep aquifer.

  The pump 41 is connected to the heat exchange hollow tube 2 and pumps up groundwater in the heat exchange hollow tube 2. The heat exchanging means 42 is connected to the pump 41 and discharges groundwater after being used to the ground and is returned to the ground. In addition, the means for reducing groundwater after use is not limited to the release to the ground, and for example, a means for reducing the groundwater may be provided separately by providing a well or the like.

  Next, the effect | action of the underground heat collection function integrated hybrid spiral pile 1c in this 3rd embodiment is demonstrated.

  Groundwater enters the heat exchange hollow tube 2 from the strainer 29. The strainer 29 prevents inflow of earth and sand and allows only groundwater to enter the heat exchange hollow tube 2. In addition, since the strainer 29 in the third embodiment is provided at the tip of the heat exchange hollow tube 2, high-temperature groundwater can be directly taken into the heat exchange hollow tube 2.

  In the pump 41, the groundwater taken into the heat exchange hollow tube 2 is pumped to the ground and supplied to the heat exchange means 42. The heat exchanging means 42 extracts heat from the groundwater and uses it for heating the structure A. The groundwater has a larger amount of heat than that collected by heat transfer from the heat exchange hollow tube 2. Therefore, the heat exchanging means 42 can extract a large amount of heat from the groundwater.

  The groundwater after being used in the heat exchange means 42 is discharged to the ground and reduced to the ground. As a result, it is possible to prevent groundwater depletion and land subsidence.

  From the above, since the underground heat collection function-integrated hybrid spiral pile 1c of the third embodiment can directly pump geothermal heat from the groundwater, it can perform efficient heat collection.

  The underground heat collection function-integrated hybrid spiral pile according to the present invention is not limited to the above-described embodiments, and can be appropriately changed.

  For example, the structure A is supported by one underground heat collection function-integrated hybrid spiral pile, but may be supported by a plurality of structures.

DESCRIPTION OF SYMBOLS 1 Geothermal heat collection function integrated hybrid spiral pile 2 Heat exchange hollow tube 3 Interior pipe 4 Heat exchange liquid circulation device 2a First heat exchange hollow tube 2b Second heat exchange hollow tube 21 Base part 22 Perforated lid 23 Water leakage prevention rubber ring 24 Groove 25 Male screw 26 Groove 27 Female screw 28 Flow port 29 Strainer 31 Flow port 41 Pump 42 Heat exchange means A Structure

Claims (6)

  A hollow tube for heat exchange that is buried in the ground and circulates heat exchange liquid or groundwater therein, the hollow tube for heat exchange being formed in a spiral with the same radius and the same pitch, and the tip thereof A hybrid spiral pile with an integrated underground heat collection function, formed in a sharp shape.   Inside the heat exchange hollow tube, an internal tube formed in a spiral shape along the heat exchange hollow tube to the vicinity of the tip is provided, and the heat exchange is provided near the tip of the internal tube. The underground heat collecting function-integrated hybrid spiral pile according to claim 1, wherein a circulation port that can circulate with the inside of the hollow tube for use is formed.   The underground heat collection function-integrated hybrid spiral pile according to claim 2, wherein the inner pipe is formed of a soft material and having a smaller outer diameter than an inner diameter of the heat exchange hollow pipe.   The base end side of the heat exchange hollow tube is connected to the heat exchange hollow tube and the base portion into which the internal tube is inserted, and the base portion is inserted and held in the base portion. A perforated lid to be screwed, and a water leakage preventing rubber ring that is reduced in diameter by pressing when the perforated lid is screwed to the base part and maintains watertightness with the interior pipe. The underground spiral heat collecting function-integrated hybrid spiral pile according to claim 3.   2. The ground according to claim 1, wherein the two heat exchange hollow tubes are arranged in close contact with each other, and at each end, a circulation port is formed to allow the flow between each other. A hybrid spiral pile with an integrated medium heat collection function. The underground heat collecting function-integrated hybrid spiral pile according to claim 1 , wherein a plurality of strainers that allow inflow or outflow of groundwater are provided in the vicinity of a tip of the heat exchange hollow tube.

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