Analysis of factors affecting the time of extra-deep hole drilling

Abstract:

To enhance the efficiency of deep and extra-deep hole drilling， this study established a drilling time utilization model based on the time allocation of drilling processes. Using this model， we quantitatively analyzed the impact of various factors on drilling time for a 13000 m extra-deep hole， comparing wireline coring with conventional coring. The analysis reveals that regardless of the drilling method， penetration per round trip is the primary factor influencing drilling time. However， the ranking of subsequent factors differs： for wireline coring， the key subsequent factors are bit life， drill-pipe stand length， and tripping speed， in that order； for conventional coring， they are drill-pipe stand length， tripping speed， and wellhead handling time. The study further confirms that wireline coring is significantly more efficient than conventional coring， but the performance gap can be effectively narrowed by optimizing key parameters such as penetration per round trip. This research reveals the critical factors and optimization pathways for drilling time in extra-deep hole drilling， providing a theoretical foundation for the evaluation of drilling methods and the enhancement of drilling efficiency.