Since horizontal openhole sections are now being drilled tornlengths that exceed 20,000 ft, placement of the completionrnstring (CS) to planned total depth (TD) may not be possiblernunder a proposed drilling plan. During the early years ofrnhorizontal-well construction, the hanging weight of therncompletion string was usually adequate to push it to TD. Withrnthe extreme lengths being attempted today, it is important tornmodel the well before attempts are made to run the plannedrncompletion to determine 1) whether the strength of the CS canrnstand the strains (tension, compression, and torque) ofrninstallation, and 2) whether there is enough weight in thernupper CS to push the lower CS to TD. A software model thatrnuses a wide range of well parameters to enable the operator tornpredict possible tension loading, compression loading, andrntorque limits on the CS during installation has long beenrnavailable. This paper discusses the software and how it can bernused in modeling well completion systems.rnTo calculate the applied forces on the completion stringrnrequires the use of a wide range of well parameters and arnspecialized software program that will allow the prediction ofrnloads and stresses that can be safely applied on the CS duringrninstallation. If the modeling process indicates that the CS willrnnot stand the stresses of installation without (1) failing fromrntensile loading, (2) buckling from the compression load, or (3)rnfailing from rotational torque, a different well plan can berndevised or other remedies employed. Charts developed fromrnactual case histories illustrate how the use of torque and dragrnmodeling can be advantageous in all phases of wellrncompletion.
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