The development condition of the offshore oil fields operated by Vietsovpetro JV (hereinafter as VSP) is characterized as the declining production stage. At the current stage, the challenging issue for VSP is to maintain the declining production by composing and implementing the well intervention activities. Well intervention planning process for offshore fields has a number of principle peculiarities, which considered at every phase of decision-making process – from analysis of geological criteria for well-candidate selection to implementation of activities. Such peculiarities may include methods and technologies of well workover and drilling, as well as seasonal operation under offshore conditions.
To allocate the wellheads and process equipment, VSP uses offshore fixed platforms (MSP) and miniMSP – wellhead platforms (BK). Well drilling on BK is done by the jack-up rigs, while MSP operations require drilling facilities and Mobile Offshore Drilling Units (MODU). MODU specification does not provide for well drilling and side tracking.
Based on the technical capability analysis of the drilling rigs, implemented for well intervention, all offshore facilities and wells are divided into groups in dependence to well operation methods.
The process of selecting the well intervention activity for the offshore fields, considers well ranking, preliminary prior to the detailed justification, depending on two key factors: availability/incapability of recompletion and operations method. Implementation of such approach during well intervention planning allows avoiding the wells with incapability to recomplete or side tracking, resulting in improved efficiency of selecting the well candidates.
The article indicates, that important components of implementing the well intervention program for the offshore fields, is their organization by offshore facilities and planning depending on number and schedule of Operator’s jack-up rigs movement.вЃ
