Improvement in Drilling Efficiency by Eliminating Static Survey Time

Abstract

Borehole survey is a very crucial element in drilling a well. The data will be utilized during all phases of drilling campaign – planning, execution, and post drilling. During planning, borehole survey data are critical to avoid well collision with nearby well. It is done through correct survey of offset data and correct toolcode assigned to the survey program together with database QAQC. While actual drilling itself, the survey will be closely monitored to ensure that the well is clear from any collision risk. The survey will guide the directional driller to steer to the geological objectives and hit the geological target with high confidence. Finally, once drilling has been completed, the survey data will be tied in to geological and reservoir models and to be used for planning of future campaign. Since the last forty years, measurement while drilling (MWD) surveys have been the backbone for the borehole surveying. MWD surveys are in fact a measurement/surveying while static condition not during online drilling itself. Industry has experienced multiple evolution of MWD surveys, but none of the evolutions lead to the survey in dynamic conditions. Realizing the true potentials of getting the survey data in dynamic condition, it will help the rigsite operation to minimize the risk associated with longer stationary time. With this definitive dynamic survey while drilling can accurately be taken while drilling, moving, rotating and sliding, it had proven to eliminate the survey-related rig time per survey and reduced associated drilling risks, therefore improves the overall drilling efficiency. The service incorporates the new telemetry innovations that enables up to 20bps and the advance drilling dynamics design includes three-axis shock and vibration and turbine power. Additionally, geological accuracy is refined using gamma ray and electromagnetic resistivity in combination with continuous six-axis direction and inclination sensors. The deployment of this dynamic-survey-while drilling service had enable the operator to acquire precise BHA location data at a higher frequency during drilling for improved decision making, eleiminating up to 15 min of survey-related rig time per survey. This also eliminated the need for additional pump cycles along with their associated washouts, stuck pipe risks and other directional drilling difficulties. The ultimate yield is definitive dynamic surveys, delivering real-time borehole conditions that reduce time to TD. This paper also covers the advance procedure of taking definitive non-static survey. The challenge is to ensure the non-static data to be sent continuously and meet survey acceptance criteria. Hence, the continuous survey data can be qualified as definitive survey and assigned a proper toolcode. To validate this continuous survey measurements, the author analyses the survey comparison with conventional static survey and gyroscopic survey results in the field test runs. The author will then present the conclusions, further work recommendations in which this wellbore surveying advancement can transform the well construction process with great impact in drilling efficiency, as well as minimizing the stuck pipe risk and wellbore uncertainty.