Oil-Based Drilling Fluid Plugging Method for Strengthening Wellbore Stability of Shale Gas

Table 12

Fracture sealing evaluation results of strong plugging drilling fluid.

System	Leaking bed	Pressure bearing time (min)	Leakage stoppage		Description of plugging of leakage bed
			Pressure (MPa)	Accumulated leakage (mL)
Formula CN-5	400 μm crack block	3	0	0	There was no drilling fluid leakage during the experiment
		3	0.5	0
		3	1.0	0
		3	2.0	0
		3	3.0	0
		3	4.0	0
		3	5.0	0