The adoption of segregated drilling campaigns is commonplace in an effort to harness economies of scale and reduce well construction costs. In an attempt to increase the financial efficiency of drilling campaigns, the division of the well construction and completions operations can be segregated into two distinct phases. A drilling and casing phase leaving a cased well in a Temporary Abandonment (TA) status, followed by a phase consisting of clean-up, completion and stimulation operations resulting in the handover of the well to production to bring hydrocarbon production online. As such an Intervention and Completion Unit (ICU) with the capability to perform perforation, multi-zone completion installation, stimulation, clean-up operations and well testing has significant advantages when deployed in the later phase of a segregated multi-phase drilling campaign.
This paper describes the collaborative development of an ICU that facilitates the installation of multi-zone and smart well completions, conveyance for well servicing operations, well bore clean-up (WBC) activities, well testing and stimulation activities. The challenge of undertaking traditional drilling phase activities with a technically capable, yet cost effective ICU is discussed, particularly the core areas where the reduction in specification through it being redundant for the phased operations.
The key parameters driving the ICU development and design are presented from the operator's perspective, based on prior campaign experience utilizing this approach with alternative technology. The process identifying the key requirements of the completion and well servicing operations is described with the selection of implementing new technology solutions in the design. The avoidance of Non-Productive Time (NPT) is a core aspiration in making incremental cost efficiencies. The identification of operations not on the critical path that can be performed simultaneously or as an offline activity, have the potential to make high cost impacts.
Through innovative design and the implementation of novel and field tested technology, allied to extensive use of offline activities as concurrent operations, the ICU has the potential to make significant cost savings in a segregated well construction project. Collaboration between the operator and service provider drives a design which provides a technically pragmatic and capable ICU and as such attracting project cost savings allied to lower support equipment costs. Further, the deployment flexibility of the ICU allows it to perform operations ranging from well construction activities such as well slot preparation, completions and intervention, to well deconstruction activities such as heavy workover, Permanent Abandonment (PA) phases and slot recovery. The ability to perform multi-phase operations whilst mobilized to a platform brings further cost benefits and operational flexibility.