Method for segmentally isolating drill hole for water pressurizing, pressure measuring and water pumping

Abstract

The invention discloses a method for segmentally isolating a drill hole for water pressurizing, pressure measuring and water pumping. The method comprises the following steps of constructing the drillhole of a test section 1 into an inverted circular truncated cone shape, installing an upper separation device and a lower separation device which correspond to the test section in shape and have certain elasticity in the test section, and applying pressure through a drill rod to compress the upper separation device and the lower separation device so as to realize segmental isolation of the drillhole. According to the method, isolation between any test section and other sections can be achieved, after isolation is formed, a pressurized-water test, a fluid pressure test and a water pumping test of a stratum corresponding to the isolation section can be conducted, and after the test is finished, the upper separation device and the lower separation device can be pulled out to realize recovery.

Description

technical field [0001] The invention relates to the field of geology, in particular to a method for segmentally isolating water pressure, pressure measurement and pumping boreholes. Background technique [0002] In the prior art, drilling is used to expose the formation, and then corresponding water pressure tests, fluid pressure tests, pumping tests, etc. are carried out for a certain section of the formation, so as to obtain the corresponding parameters of the test section of the formation. The strata are distributed in layers, and there are differences in permeability, pore pressure, and pore and fracture structure between each layer. If you want to accurately obtain the corresponding parameters of the preset layer, you must try to separate this layer from other layers to prevent the interference and influence of other layers when carrying out corresponding experiments and tests. [0003] At present, conventional boreholes are cylindrical with equal diameters. If you wan...

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Problems solved by technology

At present, there are mainly three methods commonly used: the first method is to use airbags for isolation. First, the uninflated airbags are lowered to the preset position, and then the airbags are inflated with specially installed pipelines. After the airbags are inflated, the holes in the isolation section are blocked. Generally, a test and test section in the middle of the two airbags is isolated by the upper and lower or front and rear airbags. After the test and test are completed, the airbags can be recovered after deflation. This method requires a special installation of a high-pressure pipeline for inflating the airbags. When it is lowered at the same time as the drill pipe, the space of the drilling itself is limited, and it is extremely inconvenient to lower the pipeline. For deep-hole pipelines, it is easy to be torn off. In this method, a special rope needs to be installed, and the diameter of the separation device becomes larger through the pulling effect of the rope, so as to play the role of isolation. This method also has the inconvenience of lowering the rope, and when deep holes The rope is easy to be entangled and torn off; the third is to use expansion material to prepare the partition device, such as Chinese patent 202010250896.4. This method uses the expansion effect of the material installed at a fixed position to separate different sections of the borehole, but once the partition is formed , separated material cannot be recycled and is difficult to remove

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