INSTALLATION CONSTRUCTION METHOD OF HEAT EXCHANGE INTO GROUND FOR RETRIEVING SHALLOW LAYER GEOTHERMAL ENERGY AND HOLE DRILLING DEVICE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide an installation construction method of a heat exchanger into the ground for retrieving shallow layer geothermal energy and a construction device used in the method capable of providing excellent hole drilling efficiency irrespective of type and property of soil, drilling a hole by about 2 meters per minute in a short time, and installing the heat exchanger such as a heat pump type air conditioning system up to a predetermined depth in the ground at low cost. SOLUTION: When installing the heat exchanger into the ground for retrieving shallow layer geothermal energy, a hollow pipe such as a steel pipe for drilling a hole provided with a vibrohammer in a head part and a water jet injection nozzle at a lower end is used, the hollow pipe is penetrated up to the predetermined depth in the ground using the vibration generated by the vibrohammer and water jet together. Next, bentonite slurry is poured and filled into the hollow pipe, then the hollow pipe is pulled out to hold a hole wall. Next, cement milk is poured into a hole, and the tubular heat exchanger whose lower end is folded back into U shape is inserted up to a lower end in the hole and is fixed.