Comparison of Drilling Technologies Between Top Drive and Rotary Table in Geothermal Fields: A Case Study of Olkaria Geothermal Fields

摘要

Due to accelerated drilling in the geothermal fields, there is need to adopt better drilling technologies to reduce drilling time for the well, drilling down time and increase equipment life time. One of the technologies adopted is the utilization of a top drive compared to a rotary table. A rotary table is a mechanical device on a drilling rig that provides clockwise (as viewed from above) rotational force to the drill string to facilitate the process of drilling a bore while the top drive is a motor that is suspended from the derrick, or mast of the rig to facilitate the rotation of the drill string. The aim of this paper is to compare the drilling efficiency between top drive and rotary table in terms of rate of penetration, ability to manage stuck pipe and general safety during the drilling processes. The paper will use the case study of Olkaria geothermal field whereby both the top drive and rotary table have been used to drill geothermal wells.