Well wall reinforcement condition determining method and system, and well wall reinforcement method and system

Abstract

The invention relates to the field of bored well exploration, and discloses a well wall reinforcement condition determining method and system, and a well wall reinforcement method and system. The wellwall reinforcement condition determining method comprises the steps that according to a well wall reinforcement model, preset bearing pressure of a well wall, and a fluid-solid-heat coupling equation, the target temperature, needing to be reached through cooling, of the well wall and fracture aperture distribution of fractures, extending towards the stratum, of the well wall are calculated; the temperature of drilling fluid is obtained according to the target temperature, needing to be reached through cooling, of the well wall; and particle size distribution of a reinforcement material is obtained according to the fracture aperture distribution and particle size matching criterion. According to the well wall reinforcement condition determining method, on the one hand, quantitative representation can be conducted on the required temperature of the drilling fluid in the well wall reinforcement process and particle size distribution of the reinforcement material, and accordingly, precisecontrol over the well wall reinforcement process is achieved; and on the other hand, through heat stress generated through temperature change, the influence of reinforcement material filling on the peripheral stress of a well is improved, and accordingly, the pressure bearing capacity of the well wall is improved.

Description

Technical field [0001] The present invention relates to the field of drilling and exploration, and in particular to a method and system for determining the conditions for strengthening the well wall, and a method and system for strengthening the well wall. Background technique [0002] Lost circulation refers to the phenomenon that drilling fluid leaks to the formation through fractures under the action of pressure difference. As one of the most serious downhole complications, lost circulation will not only cause the loss of drilling fluid and contaminate the reservoir, but also lead to a series of complex downhole accidents such as well collapse and blowout. These accidents cause up to economic losses to the global drilling industry every year Two to three billion US dollars. In order to prevent the occurrence of lost circulation accidents and reduce the damage caused by lost circulation, lost circulation processing technology has begun to develop from "late leak stoppage" to "...

AI Technical Summary

Problems solved by technology

Due to the difficulty of accurately predicting the opening of formation fractures, the filling efficiency of plugging materials added while drilling is low. Therefore, this method lacks quantitative construction parameters, and it is difficult to achieve fine control of the implementation process of borehole wall strengthening technology.

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