Abstract
To validate the completion model, a computer simulation was performed in four scenarios to predict mechanical failure limits. Consequently, a completion design model was obtained using vacuum-insolated tubing (VIT) that enables a minimum of 75% of steam quality given an inlet steam quality of 80%. In addition, a seal bore is used at 50° to 60° of inclination, which enables the upper completion disconnection/connection through the seal stinger at that depth, without losing production capabilities for changes in the depth of top of connection of tie-back. This paper describes the type of completion development and challenges encountered during the design. The advantages and benefits of collecting the correct information in the process of thermal recovery in the joint venture are also discussed.
The investigation resulted in a completion model of thermal wells that will enable the monitoring of the conditions of the injection, tubing, casing, and injection effectiveness in the system in which the cyclic process is applied and adjusted to wells in the Orinoco Belt. A conclusion of this investigation is that, during the injection, the movement of production string and the monitoring component must be independent to avoid the transference of stress resulting from thermal expansion. Polished bore receptacles and seal assemblies should be used in the replacement of expansion joints; this will enable the upper completion to be used for recovery and changed for the injection system.
Although completion models have been developed in which the steam path can be monitored, they have not been developed previously for use in long horizontal section wells, as was performed in this case. The problem of thermal expansion of the tubing during steam injection is expected to be resolved with the implementation of the design based on this study. Feed-through packers have already been developed especially for this process, although with a mixed record of successful and unsuccessful deployments. The monitoring system must be mechanically independent of the injection system, such that movements associated with expansion and contraction do not have a significant effect.
