JP2009041894A - Underground heat exchange method by pulling out rotary leading steel pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce cost by pulling out a leading steel pipe of an underground heat exchanger while reversely rotating it when installing the underground heat utilizing heat exchanger in the ground. <P>SOLUTION: An underground heat exchanging method comprises mounting a blade plate 6 of spiral structure to the outside of the tip of the leading steel pipe, installing the leading steel pipe 5 opened at the bottom part, while rotating it, removing sediment in the pipe, arranging the underground heat exchanger 1 in the pipe, then pulling out of leading steel pipe while rotating it reversely, and back-filling gravelly soil, sandy soil and field soil into a void in the hole after removing the steel pipe. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a method for utilizing a part or all of air-conditioning heat by a ground heat exchanger.

Conventionally, underground heat exchangers cannot be buried directly in the ground because of their depth (more than 7.0m from the ground surface) and shape (with a 180 ° elbow at the tip of the underground heat exchanger). Heat exchange is performed by installing underground heat exchangers in the air and water inside the pipes using concrete piles. (For example, refer nonpatent literature 1.).

There is a method of obtaining a pile support force by welding a spiral structure blade plate to the tip of a steel pipe pile and rotating it to a predetermined position (somewhat solid ground), but in each case, the vertical force is increased by expanding the blade plate area. To increase. (For example, refer nonpatent literature 2.).

A steel pipe pile with a spiral structure blade is welded with a steel plate at the tip of the pile to prevent intrusion of earth and sand into the steel pipe. (For example, refer nonpatent literature 3.).

Geotechnical Society of Japan Technical Data Introduction of Panel on Geothermal Use Rotating penetrating steel pipe pile with tip wing Asahi Kasei EAZET Product Basic Information

Leading steel pipes for installing underground heat exchangers are the purpose of rotating buried in the ground and reducing the frictional force on the outer periphery of the steel pipes, the shape of the blades at the tip of the steel pipes, and the method of steel pipe joints by extending the leading steel pipes.

Removal of the blocking plate that prevents intrusion of earth and sand into the steel pipe when the steel pipe pile tip is opened.

The leading steel pipe (5) for installing the underground heat exchanger (1) in the ground is a structural carbon steel pipe or stainless steel pipe, and one or more steel pipes at the tip end of the pipe are provided for half or two rounds of the outer circumference of the pipe. Four helical structure blades (6) are welded to the outer periphery of the leading steel pipe at an elevation angle of 5 ° to 20 °, the other end is added, and a circular or polygonal receiving port for fitting with the leading steel pipe, and this The upper steel pipe side that corresponds to the above is an insertion port, and a fitting socket fitting (7) is attached to the receptacle for connecting the pipe, and a fitting receptacle fitting (7A) is attached to the insertion port, and the bolt and washer (8) are attached to the fitting Rotating push-in and pull-out are performed by rotating the insertion hole of the upper steel pipe, and then installing the underground heat exchanger to the bottom of the pipe, and rotating the lead steel pipe in the reverse direction to remove the gap in the hole after removing the drawn steel pipe Backfill with dry soil, sandy soil or local soil, re-use the leading steel pipe, and how to exchange underground heat A heat exchange method characterized in that the underground heat after drawing the leading steel pipe is transmitted to the heat conduction liquid inside the underground heat exchanger, the tube of the heat exchanger having a diameter of 10 mm to 60 mm. Steel pipes, stainless steel pipes, aluminum steel pipes or cross-linked polyethylene pipes are used, and the arrangement of the tubes is U-shaped or multiple U-shaped, and the bottom of the U-shaped rotation resistance plate (3 ), A tube spacing device (4) is installed every 2.0 m to 5.0 m above this, and the inside of the tube is made into a liquid for heat conduction, and the method of exchanging underground heat is the heat conduction liquid inside the heat exchanger. The heat exchange method for ground heat according to claim 1, wherein the ground heat after drawing the leading steel pipe is transferred to a circulating type by a pump.

Unlike the vane plate aiming at increasing the supporting force of Non-Patent Document 1, the present invention is a spiral vane plate (6) aimed at unloading earth and sand and rotating steel pipes to reduce the frictional force on the outer circumference of the steel pipe. The outer peripheral friction reduction protrusion (6A) is welded.

Intrusion of earth and sand due to the opening of the leading end of the leading steel pipe is performed by a spiral drilling machine (earth auger) after the leading steel pipe is installed.

At the tip of the tube, there is a rotation resistance plate (3) for preventing co-rotation of the steel plate at the time of reverse rotation of the leading steel pipe, and a tube interval holding device (4) at intervals of 2.0 m to 5.0 m in the tube extending direction. Install.

After pulling out the leading steel pipe, the gap in the hole after steel pipe removal is backfilled to the ground surface with gravelly soil, sandy soil, or local soil.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.

In FIG. 1, (1) shows an underground heat exchanger (tube), (1A) shows a threaded socket for connecting the underground heat exchanger, and (2) shows a 180 ° elbow of the bent portion of the tube tip.

A leading steel pipe (5) is a steel pipe for installing an underground heat exchanger, and a helical structure blade (6) is welded to the outer periphery of the leading steel pipe at an elevation angle of 5 ° to 20 °.

The other end shows a joint receiving fitting (7) of a leading steel pipe, and the corresponding upper steel pipe side shows a fitting insertion fitting (7A), which is joined by fitting and joining bolts and washers (7A) for upper and lower steel pipes. To do.

The operation of the above configuration will be described below. Rotate and embed the leading steel pipe (5), place it at a predetermined position in the ground, remove the earth and sand in the pipe, and then connect the underground heat exchanger (1) with the screw socket (1A) to the bottom of the leading steel pipe Then, backfill with gravel soil or sandy soil from 1.0m to 3.0m from the ground surface, pull out the lead steel pipe on the ground while rotating backward, and fill the gap in the hole after removing the steel pipe with local earth and sand return.

Leading steel pipe for installing underground heat exchanger is spiral blade (C) (width 30mm-100mm, thickness) with diameter (K) (φ100mm-φ500mm) and elevation angle (D) (15 ° -20 °) 4 mm or more) is welded to the outer periphery of the tip, and this leading steel pipe is screwed into the ground by a rotary machine of a press pile driver combined with a spiral drilling machine (earth auger). The depth of geothermal heat utilization is 6.0 m or more from the ground surface, and it is rotationally press-fitted to the permeable layer (11) below the impermeable layer (10) deeper than this (H) (7.0 m to 30.0 m), and then The intrusion earth and sand in the leading steel pipe is removed by a spiral drilling machine, and a rotation resistance plate (E) is inserted into the U-shaped or plural U-shaped tip curved portion of the underground heat exchanger (G) (φ10 mm to φ60 mm) in the leading steel pipe. ) (Height 100mm to 400mm) is suspended in the installation leading steel pipe, the underground heat exchanger is connected to the bottom of the pipe while being connected with a threaded socket, then 1.0m to 3.0m from the ground surface Backfill with gravelly or sandy soil, pull out the lead steel pipe on the ground while rotating backward, and fill the gap in the hole after removing the steel pipe with local earth and sand.

  As described above, it is possible to reduce the cost by pulling out the leading steel pipe of the underground heat exchanger according to the present invention, and thus there is a possibility that the use of underground heat is widespread in any region.

  Sectional direction sectional drawing of the underground heat exchanger which shows embodiment of this invention   AA line sectional view of the leading steel pipe in FIG.   Side view of the leading steel pipe in Fig. 2   BB sectional view of the leading steel pipe in FIG.   Side view of the leading steel pipe in FIG.   Cross-sectional view in the longitudinal direction of the underground heat exchanger showing the completion of the embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ground heat exchanger 1A Threaded socket 2 Ground heat exchanger tip 180 ° elbow 3 Rotation resistance plate 4 Spacing device 5 Leading steel pipe 6 Spiral structure rotating plate 6A Outer friction reduction protrusion 7 Joint receiving fitting 7A Joint insertion Metal fittings 7B Bolts, washers 8 Pump 9 Radiator 10 Impervious layer 11 Permeable layer 12 Groundwater level 13 Stratum boundary line 14 Ground line

Claims (2)

The leading steel pipe (5) for installing the underground heat exchanger (1) in the ground is a structural carbon steel pipe or stainless steel pipe, and one or more steel pipes at the tip end of the pipe are provided for half or two rounds of the outer circumference of the pipe. Four helical structure blades (6) are welded to the outer periphery of the leading steel pipe at an elevation angle of 5 ° to 20 °, the other end is added, and a circular or polygonal receiving port for fitting with the leading steel pipe, and this The upper steel pipe side that corresponds to the above is an insertion port, and a fitting socket fitting (7) is attached to the receptacle for connecting the pipe, and a fitting receptacle fitting (7A) is attached to the insertion port, and the bolt and washer (8) are attached to the fitting Rotating push-in and pulling are performed by rotating the insertion hole of the upper steel pipe, and then installing the underground heat exchanger to the bottom of the pipe, and rotating the lead steel pipe in the reverse direction to remove the gap in the hole after removing the drawn steel pipe. Backfill with dry soil, sandy soil or local soil, re-use the leading steel pipe, and how to exchange underground heat A heat exchange method characterized in that the underground heat after drawing the leading steel pipe is transmitted to the heat conduction liquid inside the underground heat exchanger. The underground heat exchanger according to claim 1, wherein the tube of the heat exchanger is a carbon steel pipe for mechanical structure having a diameter of 10 mm to 60 mm, a stainless steel pipe, an aluminum steel pipe or a crosslinked polyethylene pipe, and the arrangement of the tubes is U-shaped or The U-shaped bottom is attached to the U-shaped bottom with a rotation resistance plate (3) to prevent co-rotation when the lead steel pipe rotates backward, and a tube spacing device (4) is installed every 2.0m to 5.0m above this The inside of the tube is a liquid for heat conduction, and the method of exchanging the ground heat is a circulation type by a pump in which the ground heat after drawing the leading steel pipe is transferred to the heat conduction liquid inside the heat exchanger. A heat exchange method for geothermal heat.

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