Pneumatic impact rotary drill steel well pipe device

The utility model discloses a pneumatic impact rotary drill steel well pipe device which comprises an octagonal drill rod, a power head, a transverse frame, supporting legs, a sliding clamping ring, a solid core steel well pipe, a round drill rod, a hole opening steel well pipe and a pneumatic combined drill bit. The pneumatic combined drill bit is adopted, impact energy and impact frequency are pneumatically generated and directly transmitted to the drill bit, the drill bit is driven by a drilling machine to do low-speed rotary motion, and then the impact crushing effect on fresh rocks of different sectors at the bottom of a hole is continuously achieved. And meanwhile, compressed air discharged by the impactor is used for cooling the drill bit and discharging crushed rock particles out of the body, so that hole bottom impact rotary drilling is realized. The steel well pipe is provided with the rectangular holes with the brim according to different stratum particle sizes, slurry wall protection and filler ar