Coal rock stratum hydraulic fracturing pressure monitoring device and effect evaluation and fault analysis method

Abstract

According to the coal rock stratum hydraulic fracturing pressure monitoring device and the effect evaluation and fault analysis method, an annular limiting groove A is formed in the outer portion of the middle section of a rod body at the front end of the device, and a front rubber hole sealing capsule sleeve is sleeved with the annular limiting groove A; a front hole sealing male joint is arranged at the rear end of the front end rod body; the rear end of the probe mounting rod is fixedly inserted into a first axial through hole in the left end of the front end rod body, and a visual camera is arranged in the center of the front end of the probe mounting rod; a fracturing section front end female joint and a fracturing section rear end female joint are respectively arranged at the front end and the rear end of the middle section rod body; an annular limiting groove B is formed in the outer portion of the middle section of the rear end rod body and sleeved with a rear rubber hole sealing capsule. And a rear hole sealing front end male joint is arranged at the front end of the rear end rod body. The method comprises the following steps: assembling the hole packer; observing the image to determine a fracturing point; water is injected for hole sealing, and then fracturing is conducted; stopping water injection; and carrying out effect evaluation and fault analysis according to the collected data. According to the device and the method, whether the fracturing position is reasonable or not can be judged conveniently, fault reasons can be analyzed easily, and the crack initiation pressure can be quantified easily.

Description

technical field [0001] The invention belongs to the technical field of hydraulic fracturing, and in particular relates to a coal rock formation hydraulic fracturing pressure monitoring device, effect evaluation and failure analysis method. Background technique [0002] Hydraulic fracturing technology is a reservoir stimulation technology widely used in the field of oil and gas development, and has been popularized and applied in the fields of pressure relief and permeability enhancement in coal mines, and in-situ stress measurement in deep original rocks. At this stage, the introduction of hydraulic fracturing technology into the field of coal mining has been relatively mature, and there have been many successful cases and practical experience in aspects such as ground subsidence, coal seam permeability enhancement, and hard rock roof cutting with controlled pressure relief. Its main working principle is to use the hydraulic fracturing hole sealer to seal a section in the bo...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, the hydraulic fracturing hole sealers used in coal mines mainly have the following deficiencies: (1) the location of the fracturing rock formation can only be determined by the drilling histogram of the previous geological survey, and the rationality of the location of the fracturing Unable to judge in the early stage; (2) Problems with equipment cannot be checked, for example: in the process of hydraulic fracturing, visual phenomena cannot determine whether there is a problem with the equipment or the specific location of the problem, and it still takes a lot of time to check after the withdrawal The reason for the problem; (3) The currently used sealer that integrates fracturing and sealing, the design error of the outlet pressure control of the fracturing water is too large, and it is impossible to quantify the crack initiation pressure of the sealing section, and there is uncertainty , cannot give a clear data standard

Images