| Title | Feasibility Study of Casing While Drilling Application on Geothermal Drilling Operation |
|---|---|
| Authors | Bonar MARBUN, Widiyanto WIDIYANTO, Yudhistira ADINUGRATAMA, Bramantyo Eko KURNIANTO |
| Year | 2014 |
| Conference | Stanford Geothermal Workshop |
| Keywords | drilling, casing while drilling, lost circulation |
| Abstract | Geothermal is one of the energy that formed inside the earth. This thermal energy is contained in the fluid that stored in the reservoir. To utilize this energy, it is needed to drill and produce the fluid to the surface. The geothermal rock formation is usually igneous or metamorphic rock that has a lot of fracture and high temperature. The presence of these fractures makes loss circulation even total loss as a common problem and lead to problems for the like of stuck pipe. One way to overcome these problems is drilling with Casing While Drilling (CWD) method. CWD has been widely applied in the oil and gas drilling operation. In principle, CWD is a drilling method by replacing the use of drill pipe with casing as the drill string so drilling and cementing operations can be performed simultaneously. In the oil and gas drilling operation, CWD shows a high performance drilling operation because it produce a gauge well, better wellbore stability, less possibility of loss circulation because of its plastering effect, and no need for tripping out so that drilling operation can be done safely and economically. Based on the experiences of CWD in oil and gas operations with all of benefits, it should be able to be applied in the geothermal drilling operation. CWD’s plastering effect will solve total loss problem. However, in designing CWD for drilling geothermal wells required additional attention in the selection of casing and BHA due to high temperature. The result of this study is CWD can be properly applied on geothermal drilling operation based on considerations for the likes of economically drilling operation benefits, technical design, drilling time reduction and risk of using CWD. |