Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Environmental Sciences

Coal Geology & Exploration

2023

Drilling fluid

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Prediction Of Crack Width Of Drilling Fluid Leakage Based On Neural Network, Wang Jian, Xu Jiafang, Zhao Mifu, Wang Bowen, Wang Yahua, Chen Jie, Wang Xiaohui, Yang Gang, Ma Tengfei Sep 2023

Prediction Of Crack Width Of Drilling Fluid Leakage Based On Neural Network, Wang Jian, Xu Jiafang, Zhao Mifu, Wang Bowen, Wang Yahua, Chen Jie, Wang Xiaohui, Yang Gang, Ma Tengfei

Coal Geology & Exploration

During the drilling, it is difficult to select the appropriate leakage prevention and plugging methods and materials as the development of reservoir fractures is unknown. Herein, a reservoir crack width prediction method based on neural network was proposed with reference to the actual history data of wells. Firstly, the main influencing factors of reservoir fracture width were explored and ranked by correlation analysis, and seven main influencing factors, including pump pressure, drilling fluid displacement and drilling speed, were selected as the input parameters. The rate of convergence of the model was improved using the additional momentum algorithm and the variable …


Closure Trajectory Model Of Pressure-Preserved Controller For Coring In Coal Seam Surface Well, Guo Da, Zhang Yiwei, Wang Dingming, Fang Xin, Yang Bengao, Guo Lihua, Hou Lele, Zhao Xiang Aug 2023

Closure Trajectory Model Of Pressure-Preserved Controller For Coring In Coal Seam Surface Well, Guo Da, Zhang Yiwei, Wang Dingming, Fang Xin, Yang Bengao, Guo Lihua, Hou Lele, Zhao Xiang

Coal Geology & Exploration

The traditional method of coal exploration is to obtain coal samples using an open coring tool and estimate the gas loss through theoretical calculations. However, the measured gas content of these coal samples is generally low, significantly impeding the development and utilization of coalbed methane and compromising the safety of coal mining operations. To meet the demands of deep coal exploration, an innovative pressure-preserved coring tool was specifically designed for the coal seam surface wells. This tool has a total length of 6.7 m and can extract a 3 m long pressure-preserved coal core sample at a single time. In …