This case study describes the deployment of logging tools on tractor in challenging wellbore conditions in a tight gas field in the Sultanate of Oman. Challenging conditions are defined by a high static temperature of 175°C; high static reservoir pressure of 72 MPa; a long, 5700-m wellbore; openhole configuration; and horizontal well profile. One of the conventional ways of deploying the caliper measurement in horizontal wells is through drillpipe conveyance. Deployment through coiled tubing conveyance is another option; however, this was not available owing to extensive logistical requirements and the operation's complexity. A newly developed openhole tractor designed for the well's extreme conditions was used to efficiently convey the logging tools. Features that enabled successful tool conveyance included the highest tractor force available in the industry, 6-drive tandem wheels, real-time adjustment of the radial force to the tractor arms, and active traction control for improved maneuverability. Calipers were successfully conveyed with the wireline tractor in the 800-m horizontal section of the 5000-m-deep well. The logging job took only 12 hours versus the traditional 60 hours required to convey the same tools on drillpipe. In addition, the tractor conveyance minimized the risks associated with operating at high temperature because it significantly reduced the time of exposure of tools to extreme high temperatures approaching their maximum temperature ratings, hence ensuring top performance and reliability. The fivefold time reduction also helped with the well economics and minimized the overall operational risks associated with the logging operation. The recorded caliper data enabled proper evaluation of the hole conditions for selecting the best location for setting the swellable packers.

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