| Title | Extended Reach and High Inclination Drilling Geothermal Well in Wayang Windu |
|---|---|
| Authors | Jose PRIHUTOMO, Yudi HARTONO, Jeffri SAMOSIR, Roberto ABANES |
| Year | 2012 |
| Conference | Stanford Geothermal Workshop |
| Keywords | extended reach, high inclination, loss circulation, insufficient casing weight, lack of offset data |
| Abstract | On 2011, Star Energy Geothermal Wayang Windu, Ltd (SEGWW) embarks into drilling geothermal wells in the Wayang Windu area purposely to enhance its steam supply and explore additional field for further evaluation and development. The drilling continuous without any major difficulties encountered. After drilling four wells with an average depth of 1800 meters, SEGWW subsurface team proposed to delineate to areas where a high angle drilling is necessary to reach possible faults that may enhance steam supply. The design of this well with a long reach drilling target, calls for a 67 deg angle and slightly build to reach the final fault. The well is intended to confirm additional reserves and gather additional data that is necessary in confirming the field steam supply situation. This created a situation where drilling team members were uncomfortable as this is the first high angle well in Wayang Windu and all other geothermal fields in Indonesia and probably in Asia. The lack of offset data made it uncertain to accomplish this ambitious plan of a long reach drilling in geothermal wells. One critical factor that is very challenging is the risk of drilling extended reach and high angle under loss circulation zone. Other high potential risks during drilling that were identified are: very tight window of target, loss circulation during steering, insufficient hole cleaning, insufficient casing weight to land it on bottom, no directional control during drilling the last hole section and unknown formation behavior. This paper presents a success story of the SEGWW drilling team on this extended reach and high angle well. It was completed to a final hole inclination of 80 deg at 2450 meters. The team composed of highly motivated and dedicated personnel and fully supported by Star Energy management made this “NEVER BEEN DONE” before drilling program a success. The well was completed with a minimum none productive time as well as below budget and on target. The success outcome make the level of confidence for SEGWW drilling team to drill high angle in Wayang Windu area. |