Experiment on technical parameters of air drilling in floppy coal seam

The wind flow and pressure lose in the air drilling in floppy coal seam were analyzed and calculated by the two phase flow principle. The pressure lose in the pneumatic slag off was studied through the simulative experiment. Based on the industrial experiment, the empirical formula of the wind pressure needed in drilling was acquired. The result would supply reference for air drilling in floppy coal seam in coal mine.