Effective Approach for Enhancement of Rigless Well Commissioning

Abstract

Rigless well commissioning is an important stage of well completion to deliver a new drilled or worked-over wells (oil producer or water/gas injector) ready for production or injection. Rigless well commissioning employs firstly slick wireline intervention for well accessibility verification, down hole safety valve operability, bottom hole pressure and fluid gradient survey that assists to design the flow to clean commissioning program. Secondly, it employs coiled tubing (CT) and flow to clean (FTC) packages to cleanup the well and if necessary to perform matrix acidizing to improve well productivity or injectivity. This paper highlights operational constraints of well commissioning and its effective approach from job design, execution and evaluation that have been performed over 250 wells in the span of 5 years operations. The commissioned wells are drilled in the carbonate formation with surface clustered operation in Onshore and Offshore Artificial Islands. It also describes HSE challenges that have been faced in safe handling of return fluid, management of volatile recovered crude oil, simultaneous operations (SIMOPS) with Drilling Rig, Project and Construction (P&C) activities and hydrocarbon flaring in the environmentally sensitive area. The implemented approach and methodology of well commissioning has evolved significantly to address operational challenges and reducing well commissioning cost by 60%. It proves improvement of operating efficiency of CT and FTC packages based on downhole pressure survey, smart well commissioning, eliminating high risk clean-up operation for injector well, cluster based well commissioning, in-situ return fluid management and arrangement of vertical flare stack in the constraint offshore artificial island. The overall outcomes have achieved technical objective with optimized cost and minimum risk, enhancing rigless package utilization and implementing sustainable and effective field rigless commissioning.