Managing fatigue in tube used for drilling comprises using individual means of identification to record parameter giving cumulative fatigue for tube

摘要

The work done by the tube (8) is determined by identifying the start of its descent to operate a drill and the completion of its re-lifting; calculating a parameter which is a function of the fatigue damage to the tube after this work, and writing on the individual means of identification (20) the value of this parameter to obtain an indication of the cumulative fatigue for the tube : The fatigue arises from work done by the tube during drilling operations. The parameter is calculated taking into account at least the architecture of the drill, the characteristics of the tube and the stimuli applied to the pipe. A finite element calculation program is used to determine the loads imposed on the tube during the work done. The indicator of cumulative fatigue sets off an alarm when it reaches a threshold value. A central computer carries out the calculation and records the parameter and controls the updating of the tube fatigue indicator. The computer can be a long way away from the drilling operation and carries out the calculation, recording and updating by a transmission, for example via the Internet. Independent claims are also included for the following: (1) a system for managing fatigue in a tube as above, comprising at least one read/write mechanism (14) for the individual identifications (20); a central computer with databases giving the characteristics of the tube, operating data of the work generating the fatigue, means of collecting the stimuli applied to the tube, means of calculating the fatigue damage and means of controlling the writing on the means of identification, where the tube passes in front of the detector at the start and end of the drilling operation and a portable reading/writing tool (19) is designed to verify the fatigue damage on the tube; and (2) the application of the above process to drill strings and/or extension tubes for risers in offshore drilling.