An intelligent identification method of safety risk while drilling in gas drilling

HU Wanjun,XIA Wenhe,LI Yongjie,JIANG Jun,LI Gao,CHEN Yijian

Table 3. Schematic table of single sample

No. Formation gas production sample Normal drilling sample Pipeline A discharge pressure/ kPa Pipeline B discharge pressure/ kPa Standpipe discharge pressure/ MPa Methane volume fraction/ % Oxygen volume fraction/ % Pipeline A discharge pressure/ kPa Pipeline B discharge pressure/ kPa Standpipe discharge pressure/ MPa Methane volume fraction/ % Oxygen volume fraction/ % 1 35.98 30.50 2.08 75.63 1.27 12.43 10.48 2.44 0 3.29 2 36.23 30.55 2.32 84.30 0.93 12.48 10.55 2.45 0 3.29 … … … … … … … … … … … 19 37.10 31.63 2.64 94.24 0.12 12.28 10.33 2.44 0 3.29 20 37.53 31.70 2.83 93.39 0.11 12.28 10.38 2.44 0 3.29