Abstract

One of the main constraints facing many offshore platforms is the shortage of accommodation. The balance between continuing field development and maintaining existing production and platform integrity inevitably requires a compromise in the crew allocation for well engineering activities.

This paper will discuss the challenge faced on Shell's Gannet Alpha platform in conducting a coiled tubing managed pressure drilling (CTMPD) operation with a 20% reduction in crew numbers over the previous CTMPD operation. The key enabler of this reduction was the use of a supplier's established onshore control centre located in Norway for remote support. A two-way real time data connection from the platform was established that allowed two key roles to be removed from the platform - drilling data acquisition and quality control, and control of a dynamic annular pressure control system.

This implementation of remote support was unique as the main drilling supplier not only used this facility to reduce his rig-site presence but also facilitated other third party suppliers to remotely operate their equipment by providing space and IT infrastructure within the facility.

As well as the principle benefit of reducing personnel on board required to run the CTMPD, additional benefits were realised through the dissemination of real-time data throughout the operator and supplier organisations. By utilising the WITSML data protocol, the operators reservoir model and well-planning programs were populated in real-time enabling subject experts to participate in the decision making process. Additionally, onshore technical support and engineering personnel were able to utilise the two way connection to access the offshore systems in real-time in order to troubleshoot problems, perform software upgrades and carry out diagnostics on surface hardware and downhole tools as required.

This paper will describe the upfront preparation both in terms of the IT infrastructure and the personnel multi-skilling. It will then describe the ways in which the data was transmitted and used during the operation, and the contingency procedures that were developed in the event of loss of communication. Finally, the future of real time operations will be discussed and how the learnings from this operation can be used in the ongoing development of this technology.

Introduction
Background

The Gannet 'A' platform is located in the central North Sea, approximately 120 miles East of Aberdeen. As well as the Gannet 'A' field, there are a further 6 subsea fields tied back to the platform. A requirement for infill drilling was identified in order to continue the development of the field.

Drilling Methodology

The original Gannet A wells were drilled with the assistance of a tender vessel which primarily provided pumping, fluids handling, solids control and accommodation services. An infill drilling feasability study concluded that re-instatement of the existing platform drilling equipment was not viable and that coiled tubing drilling was the most economic option for accessing the stranded reserves.

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