Drilling unit

Abstract

A drilling unit is provided with a top drive which is mobile along a drilling axis in order to move drilling rods, with two telescopic drilling masts which are arranged facing each other, a cable device and a hydraulic device which co-operate with each other to move the top drive along a support guide which is parallel to the axis and is arranged in an intermediate position in relation to the two drilling masts for supporting and sliding the top drive along the axis. A hydraulic actuator for each drilling mast is suitable for modifying a longitudinal length of the relative drilling mast. A control station is suitable for controlling the actuation of each hydraulic actuator either in simultaneous or independent fashion.

1 . Drilling unit comprising a top drive which is mobile along a drilling axis to move drilling rods, and a movement group of the top drive comprising a cable device and a hydraulic device co-operating with the cable device to move the top drive along the drilling axis; the unit comprising two drilling masts arranged facing and parallel to each other and a support guide arranged side by side and in an intermediate position in relation to the two drilling masts to support and slide the top drive along the drilling axis; the hydraulic device being provided with a hydraulic actuator for each drilling mast suitable for modifying a longitudinal length of the drilling mast, and with a control station for the actuation of the hydraulic actuators either in simultaneous or independent fashion.  
   
   
       2 . Drilling unit according to  claim 1 , wherein each drilling mast comprises a telescopic mast having a fixed trellis and a sliding trellis inside the fixed trellis; the relative hydraulic actuator being interposed between the fixed trellis and the mobile trellis to modify the length of the telescopic mast in such a way as to move the top drive along the support guide.  
   
   
       3 . Drilling unit according to  claim 2 , wherein the cable device is provided with at least a pair of hanging sheaves for each drilling mast arranged at the head of the relative mobile trellis, and with at least an additional pair of hanging sheaves associated with the top drive.  
   
   
       4 . Drilling unit according to  claim 3 , comprising a trolley coupled in sliding fashion along the guide to support the top drive and the relative pair of hanging sheaves.  
   
   
       5 . Drilling unit according to  claim 4 , wherein the cable device comprises at least a double pull of cables, each of which is fixed at its own opposite ends to respective dead ends and which winds around a respective pair of hanging sheaves of each telescopic mast and around a respective pair of hanging sheaves of the top drive.  
   
   
       6 . Drilling unit according to  claim 5 , wherein the hydraulic actuators comprise relative hydraulic cylinders.  
   
   
       7 . Drilling unit according to  claim 6 , wherein the hydraulic cylinders present equal entities of engine power.  
   
   
       8 . Drilling unit according to  claim 1  comprising a support structure on which are mounted the drilling masts and the support guide.