Rigless Drilling and Completion: A Case Study of Re-Entry Drilling and Completion with 340K HWU to Re-Access Exploration Well in Mahakam Swamp Field, Indonesia

Abstract An exploration well was temporarily abandoned in 2021 due to being concluded as dry hole with hydrocarbon indication after testing of reservoir zone at the bottommost stratigraphy unit. However, current well status is inconclusive since there are several promising zones above the previously tested zone which need to be tested. Hence, in order to optimize the budget and perform the test in rigless mode, 340K HWU was utilized to perform re-entry, workover and completion. In order to re-access and perform completion of this temporarily abandoned exploration well, the access had to be cleared out down to top of Cement Plug#1 at 4040 mMD. Thus, Cement Plug#2 overlapping 7" Liner and 9-7/8" Casing had to be drilled out. Furthermore, there was a layer of contaminated cement in the 7" Liner that had be drilled out before reaching the top of Cement Plug#1. Once the access to top of Cement Plug#1 was achieved, the well was then completed with tubingless completion. This whole operation was performed by 340K HWU incorporated by some drilling services. This workover operation took six (6) months of preparation and thirty-two (32) days of execution. It managed to reach the target depth at 4041.37 mMD which was probably set a new record of the deepest operational depth for 340K HWU. In addition, the tubingless completion of this well was set with end of tubing at 4030 mMD. The operation was completed without loss time injury and major safety issue. This operation obviously proved to be another milestone and set a new record for 340K HWU. With new capability of 340K HWU being discovered, new potential and opportunity are now wide open for further improvement and certainly cost optimization.