Successful Intervention in U and W Shaped Wells in Eagleford Basin – A Case History

An operator in Eagleford basin, decided to optimize production, by minimizing drilling efforts. This led to two wells drilled in a distinctive "U" and "W" shape, which would result in equivalent treatable laterals lengths in a lease with tight boundaries. Plug and Perf stimulation technique was carried out in these two wells and post stimulation cleanout had to be performed. Intervention in these unique shaped wells need to be planned with the proper Bottomhole Assembly (BHA) configurations to ensure that that no misrun occurs. Though these wells are drilled successfully with the rig, since there is rotational and axial capabilities, it does not necessarily mean that a Coiled Tubing (CT) intervention would be less challenging. The frac plugs for isolation were set not just in the straight sections of the well but also in some part of the bend as well. This paper will highlight the operational planning that was involved prior to performing intervention in these two wells. A complete coiled tubing modelling along with bending analysis on the milling BHA was performed to ensure that the downhole assembly does not undergo any failures due to well profile. A total of 32 frac plugs in "W" shaped well and 38 frac plugs in "U" shaped well were successfully cleaned/milled out. The two wells were completed with 5 ½", 23 lb/ft casing with a Measured Depth (MD) of 17,846 ft and 21,064 ft respectively. A 4 ½" Tricone bit along with a 3 1/8" workover motor and extended reach tool was utilized for the operation. Due to the pre-planning performed during the BHA selection, it eliminated a second run in each well, thereby allowing the operator to save around $150,000 on intervention costs. This paper will act as a guideline for any future intervention planned in wells with unique geometry.