Abstract: A fracturing method, to cause a crack in bedrock, includes installing a depressurizing device in a well in the bedrock, and depressurizing the inside of the well with the installed depressurizing device. The installing step includes installing, in the well, a connecting pipe, which is connected to the depressurizing device, and a packer, which is attached to the connecting pipe, and the depressurizing step includes shutting off a gap between the well and the connecting pipe, with the packer, and depressurizing a region in the well below the packer, with the depressurizing device.
Type:
Grant
Filed:
January 31, 2019
Date of Patent:
May 10, 2022
Assignees:
NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, THE UNIVERSITY OF TOKYO, TOHOKU UNIVERSITY, JMC GEOTHERMAL ENGINEERING CO., LTD., INPEX DRILLING CO., LTD.
Abstract: A well drilling bit for drilling bedrocks includes a columnar bit body, and a drilling fluid flow path formed in the bit body to wash away drilled cuttings from a bottomhole and/or a periphery of the bit body. The flow path is provided with a venturi mechanism including a venturi tube having a reduced-diameter portion where a cross sectional area is reduced and capable of generating a decompression region around a tip of the bit body, the decompression region being more decompressed than a surrounding by the Venturi effect.
Type:
Grant
Filed:
December 12, 2017
Date of Patent:
January 25, 2022
Assignees:
THE UNIVERSITY OF TOKYO, TOHOKU UNIVERSITY, INPEX DRILLING CO., LTD.