System and method for measuring and controlling rotation of coiled tubing

A method for determining fatigue life of coiled tubing, the method comprising the steps of

• moving coiled tubing into a bore through an apparatus, the apparatus comprising a reel structure for said coiled tubing including a reel on which said coiled tubing is wound and a frame supporting the reel for rotation, an injector structure for running the coiled tubing from the reel structure into said bore and for withdrawing said coiled tubing from the bore, sensor means for continuously monitoring sensing and recording rotation of said coiled tubing and for measuring amount of said rotation, said sensor means including means for receiving and transmitting data relating to said characteristics of the coiled tubing, and a computer means for receiving data from said sensor means and processing said data to determine fatigue life of said coiled tubing,
• sensing with the sensor means rotation of a portion of the coiled tubing previously moved into the bore by the apparatus, and transmitting data related thereto to the computer means, and
• determining with the computer means the fatigue life of said portion of said coiled tubing.