A Novel Approach of Wireline Intervention for Newly Drilled Well: Sotong Case Study and Best Practices

Abstract

Sotong-A9 was drilled in dual completion. Maximum target production is 3000 bbl/d for the long string while short string capable to produce 20 mmscd. Sotong platform was the highest producer for MASA field located about 135 km offshore Terengganu which comprises of Malong, Anding and Sotong. Currently all the produced oil and gas is process and store on FPSO facilities located nearby. During completion stages an "unknown" fish was left in hole thus hindering wireline intervention to open SSD to unload zone below the fish depth. Total potential reserve for both zones is estimate 20 million barrel of oil. Due to that, wireline operation to retrieve the fish was considered critical due of fear for leaving the zone with completion fluid can damages the formation. There were 2 wells included in the infill drilling campaign. Any delay due to fishing job can contribute to higher rig cost. Prior to actual job execution, few main challenges need to properly addressed such as job coordination/people management, well pressure control and slickline equipment rig up complexity. Therefore, while the drilling continue in Stg-03 well, slickline intervention for fishing operation was continue at well Stg-09L with the 21–1/4" conductor BOP still attached on it. Slickline lubricator is rig-up on top of the existing BOP prior to fishing job and pressure test was carried out to ensure the well pressure containment. This novel technique contributed to cost saving of USD 400K due to no requirement for rig standby for conductor BOP removal. This paper discussed on best practices of rig up wireline in existing drilling BOP, Job Hazard Analysis (JHA), job procedures and lesson learned. Introduction Sotong is a part of integrated marginal field development called MASA which also comprised Malong and Anding fields. Crude and gas are processed at nearby FPSO called Perintis. Same like its adjacent field, Sotong platform was built following small and remote platform philosophy; small deck space and very small crane capability. Thus, for the whole drilling campaign, rig crane is the only equipment that can be depended on for any lifting operation. Sotong infill drilling was planned to complete Sotong-A9 and Sotong-A3 as dual completions. Sotong-A9 was the first well to be completed prior to Sotong-A3 and the target completion for both wells was about 2 months. Sotong-A9L was drilled to drain K2 - K 7.2 and L sand, in which production target was about 3000 bbl per day. Satisfied with the first oil from the well, drilling team decided to start drilling Sotong-A3 as per original plan and left 21 ¼" conductors blowout preventer (BOP) still attached to wellhead area to save rig time.