Methods and devices for controlling a mechanical joining or forming process, in particular friction drilling in thin-walled materials, apply several reverse pulses acting on a process parameter to bring the course of an actual curve of the parameter more into line with the course of a predetermined nominal curve of the process parameter. The number and length of the reverse pulses and the length of the intervals between the pulses are determined as a function of at least one immediately detectable variable associated with the process parameter.

A pipe facing machine (PFM) system includes a PFM and a hydraulic power source having a single hydraulic pump arranged to provide a hydraulic oil flow to the PFM via single hydraulic circuit. The PFM includes a body defining an axis and a cutting head arranged to rotate and translate relative to the axis. Drive systems are arranged to drive clamping of the PFM on a workpiece, rotation of the cutting head about the axis, and translation of the cutting head along the axis. A hydraulic controller includes a plurality of control elements and hydraulically connects the drive systems. The hydraulic controller is arranged to direct and regulate hydraulic oil flow between the drive systems and the hydraulic controller based on signals from the control elements and a computer control system.

According to one implementation, a tool feeding mechanism for a handheld tool rotating device, having a holder and a first air motor, includes a coupler, a fixing member, a moving mechanism and a second air motor. The holder chucks and holds a rotating tool. The first air motor rotates the holder. The tool feeding mechanism is attached to the tool rotating device. The coupler is attached to the tool rotating device. The fixing member is attached directly or indirectly to a workpiece of hole processing using the rotating tool. The moving mechanism moves the coupler relatively to the fixing member in a tool axis direction. The second air motor powers the moving mechanism.

Methods and devices for controlling a mechanical joining or forming process, in particular friction drilling in thin-walled materials, apply several reverse pulses acting on a process parameter to bring the course of an actual curve of the parameter more into line with the course of a predetermined nominal curve of the process parameter. The number and length of the reverse pulses and the length of the intervals between the pulses are determined as a function of at least one immediately detectable variable associated with the process parameter.

According to one implementation, a tool feeding mechanism for a handheld tool rotating device, having a holder and a first air motor, includes a coupler, a fixing member, a moving mechanism and a second air motor. The holder chucks and holds a rotating tool. The first air motor rotates the holder. The tool feeding mechanism is attached to the tool rotating device. The coupler is attached to the tool rotating device. The fixing member is attached directly or indirectly to a workpiece of hole processing using the rotating tool. The moving mechanism moves the coupler relatively to the fixing member in a tool axis direction. The second air motor powers the moving mechanism.

A pipe facing machine (PFM) system includes a PFM and a hydraulic power source having a single hydraulic pump arranged to provide a hydraulic oil flow to the PFM via single hydraulic circuit. The PFM includes a body defining an axis and a cutting head arranged to rotate and translate relative to the axis. Drive systems are arranged to drive clamping of the PFM on a workpiece, rotation of the cutting head about the axis, and translation of the cutting head along the axis. A hydraulic controller includes a plurality of control elements and hydraulically connects the drive systems. The hydraulic controller is arranged to direct and regulate hydraulic oil flow between the drive systems and the hydraulic controller based on signals from the control elements and a computer control system.