Rotary drilling rig

The invention discloses a rotary drilling rig. The drilling rig comprises a chassis, an operating room arranged on the chassis, and a mast arranged on the operating room; a lifting platform is arranged on the mast, a rotary excavating power head is arranged on the lifting platform, a hollow drill rod is arranged on the rotary excavating power head, a rotary excavating drill barrel is fixedly connected to one end of the hollow drill rod, and an inner cavity of the rotary excavating drill barrel is communicated with an inner cavity of the hollow drill rod; the other end of the hollow drill rod is rotationally sleeved with a discharging barrel, and the discharging barrel is fixedly connected with the lifting platform, so the hollow drill rod can rotate in the axial direction of the discharging barrel; a first discharging pump is arranged in the rotary drilling barrel, a second discharging pump is arranged in the discharging barrel, and a conveying pipe is further arranged on the barrel wall of the end, away from