Developmental Research on Cutting a Notch in Deep Borehole for Hydraulic Fracturing with High Speed Waterjets

高速水射流深孔水力压裂切槽开发研究

基本信息

批准号：
62850111
负责人：
MATSUKI Koji
金额：
$ 2.18万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62850111/
关键词：
Rock Hydraulic fracturing Artificial slit High speed waterjets High water pressure 溝切削

项目摘要

In order to clarify the applicability of high speed waterjets technology to making a slit in deep borehole for hydraulic fracturing, the testing apparatus was manufactured first to simulate the slot cutting of rock in deep water up to 2000m and then, the effects of various cutting parameters such as driving pressure, standoff distance, nozzle diameter and traverse rate on the depth of cut, the slot width and the specific energy were investigated for Shirakawa welded tuff using the driving pressure up to 100 MPa and flow rate of 80 1/min.The main results obtained in this study are summarized as follows;1) Although the depth of cut rapidly decreases with circumferential water pressure, if finally becomes almost constant at about 10 MPa of water pressure. Maximum depth of cut was 32.2 mm under water pressure of 20 MPa for Shirakawa welded tuff.2) Main cutting mechanism is cavitation errosion for the smaller cavitation number less than 0.05, and for larger cavitation number other mechamisms predominate.3) Empirical formulae on the depth of cut were proposed for both regions where the depth of cut depends on circumferential water pressure and where it is independent of water pressure.4) It is found that there exists an optimum water pressure and optimum standoff distance from the view point of energy consumption.5) The width of slot rapidly increases with water pressure until it reaches almost constant value.6) High speed waterjets can be applied to making a slit in deep borehole for hydraulic fracturing.

In order to clarify the applicability of high speed waterjets technology to making a slit in deep borehole for hydraulic fracturing, the testing apparatus was manufactured first to simulate the slot cutting of rock in deep water up to 2000m and then, the effects of various cutting parameters such as driving pressure, standoff distance, nozzle diameter and traverse rate on the depth of cut, the slot width and the specific energy were investigated for Shirakawa使用高达100 MPa的驱动压力和80 1/min的流量。本研究中获得的主要结果总结如下：1）尽管最终在10 MPA的水压下几乎变为恒定，但切割的深度随着圆周水压的速度迅速降低。 Shirakawa焊接凝灰岩的水压在20 MPa的水压下的最大最大切割深度为32.2毫米。2）主要切割机制是较小的空中数小于0.05的较小的空置数字，而对于较大的空化数量，其他机电症却遭受了偏爱。3）较大的距离较高的距离，该区域的距离是较高的，该区域均依赖于较高的距离，该区域的水平是依赖于水的独立性。发现从能量消耗的角度来看，存在最佳的水压和最佳的隔离距离。5）插槽的宽度随水压迅速增加，直到达到几乎恒定的值。6）高速水夹可以应用于在深井中制造液压分裂的高钻孔。