be easily and quickly handled in this new type rig the mast derrick defines a vertical shaft arrangement with a static hook load capability or pulling power up to 1000 tons and a useful vertical driving head stroke from the top to the bottom of 30 meters or more and the mast derrick 3 can comprise either a telescopic or a fixed construction for vertically driving said head 4 by one two or more worms screws which are rotatively driven by a pinion gear wheel system controlled either by high power dc or ac electric motors or by hydraulic motors as stated and with reference to fig1 a the tubular element loader lay up and down machine l 1 mounted in front of said substructure or platform include gripping arm clamps c for gripping the tubular elements or pipes p from a pipe container pc or oscillating pipe rack said loader means l 1 after having gripped each tubular element p performing a 90 u00b0 turning movement advancing toward the center of the well whereas a telescopic hydraulic cylinder not shown raises the tubular elements p engaged therein to bring said tubular elements on the axis of the top drive to screw on them and then as required to screw off them and bring them again to their containers pc which can be oscillated from a horizontal position to a vertical position to facilitate the loading therein of the tubular elements p a further advantage if the inventive rig is that it can be automatically controlled by a single operator operating a plc in turn.