Abstract: A twin-head beveling machine for high-precision machining on heads of pipes, comprising two mutually opposite pressers and machining heads with a rotating disk; the pressers are rigidly connected to each other by a central fixed shaft and the heads are mounted so that they can rotate and move axially individually on the central fixed shaft. The machining heads are subjected to the action of hydraulic or pneumatic motors and of axial movement elements, which are activated by a respective hydraulic or pneumatic actuator and produce the axial working advancement of the respective head.

Abstract: A twin-head beveling machine for high-precision machining on heads of pipes, comprising two mutually opposite pressers and machining heads with a rotating disk; the pressers are rigidly connected to each other by a central fixed shaft and the heads are mounted so that they can rotate and move axially individually on the central fixed shaft. The machining heads are subjected to the action of hydraulic or pneumatic motors and of axial movement elements, which are activated by a respective hydraulic or pneumatic actuator and produce the axial working advancement of the respective head.

Abstract: A method consisting in forming a preliminary excavation along the pipe and in then digging, starting from the bottom of the preliminary excavation, two lateral trenches that are adjacent to the sides of the pipe, converge downwardly, and go deeper than the level set for the final excavation bed that lies below the pipe, so as to form respective lateral collection channels; and in removing, by cutting, the wall that separates the trenches in the region below the pipe, dumping the corresponding residual material into the lateral collection channels. The invention also relates to an apparatus, of the integral type or composed of dedicated units, for digging the lateral trenches and/or for cutting away the wall that lies below the pipe.