Gas extraction drilling and blowing hole repairing device and method

The invention provides a gas extraction hole drilling and blowing repairing device and method. The gas extraction hole drilling and blowing repairing device comprises a hole sealing pipe and a drainage opening which is communicated with the hole sealing pipe and used for drainage of gas. The repairing device further comprises a pressure air inlet, a blowout prevention outlet and a drainage valve. And the pressure air inlet is communicated with the hole sealing pipe through a pressure air inlet valve so as to input high-pressure air flow into the hole sealing pipe. And the blowout prevention outlet is communicated with the hole sealing pipe through the blowout prevention valve, so that high-pressure airflow carrying coal cinder and gas is discharged from the blowout prevention outlet after the high-pressure airflow is input into the hole sealing pipe from the pressure air inlet. The drainage valve is arranged at the drainage opening so that the drainage opening can be closed when high-pressure air flow is inpu