Abstract

This paper presents the experience gained by Total Indonesie and their future plans for the application of the Navigation Drilling System in the development of the Handil field.

The Handil oil field is located in the Mahakam Delta, East Kalimantan. The field is developed by grouping wells in cluster locations alongside existing rivers, hence the majority of the wells are deviated.

Experience showed that a conventional directional drilling system (i.e. using a straight motor, a bentsub and steering tools) was no longer suitable for drilling in Handil due to the following reasons:

• increased well kick-off depths

• increased number of targets, which are drilled through different production zones

• decreased size of target oil columns as the field matured (i.e. due to water rise and gas cap expansion)

• increase risk of collision with existing wells.

Since mid 1987, the "conventional" drilling system is being gradually replaced by a so-called Navigation Drilling System (i.e. using a double-tilt steerable motor (DTU) or, where a high build up rate (BUR) is required, using a single-tilt steerable motor (TKO)). The new system is combined with Measurement While Drilling MWD logging tools.

The success of the new technique proved to be sensitive to bit selection. Although improvements in bottom hole assembly design are still required to minimized motor hang-up problems, the Navigation Drilling System performance is promising.