Multi-joint stands 126, 127 of drill pipe are assembled and disassembled in a drilling rig 15 by use of a powered mousehole 11 concurrently with well drilling operations conducted by use of a drill string top drive system 23. The powered mousehole 11 has an upwardly open bowl 45 in a floor 17 of the...http://www.google.fr/patents/US5351767?utm_source=gb-gplus-shareBrevet US5351767 - Drill pipe handling
