Adapting Extended-Reach, Float-in Tubular-Running Practices to SAGD Completions

Abstract

High torque-and-drag (T&D) values can increase the difficulty of installing tubing in extended reach steam-assisted gravity drainage (SAGD) wells. Extra surface applied compressional force (tubing jacks) is often needed to land the tubing, leading to increased completion operation time and costs, and increased hazard potential. In many cases the likelihood of sinusoidal and helical buckling of the production tubing is also significant. A method of running tubing in extended-reach horizontal wells is presented which uses pipe floatation to reduce sliding friction in the lateral section. For SAGD wells in the subject area, the operator was able to eliminate the use of tubing jacks to run production tubing to the toe of the well. Data was acquired that allowed the comparison of tubing load conditions, both with and without the floatation method. This data was also compared with torque-and-drag (T&D) modeling results to illustrate the reduction in friction that was achieved and quantify the benefit of the method.Typically, SAGD wells are completed with two strings of tubing: a long tubing string landed near the toe of the well, and a short tubing string landed near the heel of the well. This is to facilitate the circulation of steam in the early stages of well development. Landing tubing at the toe of the well can be challenging in high ratio extended-reach wells due to the combined effects of frictional forces in the lateral section and the relatively shallow vertical depth of the reservoir.The conventional method to land tubing in extended-reach or mega-reach SAGD wells utilizes tubing jacks, also known as Љpull-downsЉ, to apply force to the tubular after it stops moving under its own weight. This method can be used to successfully land tubing, but is inefficient due to additional rig up time for the jack equipment, and slow run-in-hole speeds when compared to running tubing into the well under its own weight. Additionally, tubing that encounters resistance when running in the hole, is more susceptible to helical and sinusoidal buckling which can result in early fatigue, plastic deformation and lock-up of the tubing during running (Wu and Juvkam-Wold 1993).