Tunneling device and method

The invention provides a tunneling device. The device is applicable to a shield construction method and can achieve annular tunneling in a stratum. The tunneling device (1) capable of achieving annular tunneling in the stratum includes a tunneling device body (2) and a tunneling mechanism (4). The tunneling mechanism (4) is arranged at the front end of the tunneling device body (2), rotatably driven relative to the tunneling device body (2) and provided with a cylindrical external rack (24), a cylindrical internal rack (26), a radial rack (28) and tunneling heads (30). The cylindrical internalrack (26) is axially arranged with the external rack (24); the radial rack (28) is connected to the internal rack (26) and the external rack (24) and extends in a radial direction; the tunneling heads (30) are arranged on the front end faces of the external rack (24), internal rack (26) and radial rack (28). A brim part of the rear portion of the radial inner side of the radial rack (28) tilts backward to the radial oute