The Changing Role of the Remotely Operated Vehicle in Offshore Operations

ABSTRACT The ROV's role in satisfying the requirements of the offshore production industry has been one of constant change over the years. As technical, operational and commercial experience has been gained, new and more demanding challenges have been identified. This paper demonstrates the capabilities of ROVs and their associated technology in meeting these new demands dictated by deepwater operations, increased safety requirements and low oil prices. INTRODUCTION ROVs and their associated intervention tools have been gradually eroding the well established role of the diver. This is clearly evident by the reduction in the number of divers to date supporting the industry compared with the increase in the number of ROV's and their associated personnel. Historically a large quantity of equipment and numerous personnel were required to support a simple diving system whose duties on a drilling rig for example were establishing wellhead guide wires and the occasional operation of valves. The introduction of the ROV however was in itself a traumatic period and most divers have their own ROV recovery tale to tell. These early machines had not been designed for the rigours of offshore use and were therefore generally unreliable. The ROV's potential was recognised, however, which encouraged companies to invest in these machines and improve their performance to acceptable levels. In addition to the machines themselves, their launch and recovery systems were also improved. Early launch systems such as articulated cranes. (commonly fitted to trucks) have been replaced with purpose designed "A" frames and towers etc. to cater for the general increased weights of the modern ROV, its tether management system and to provide a contingency for intervention equipment etc. In addition, systems are now generally designed to comply with offshore lifting regUlations e.g. "DnV Code of Practice for Offshore Lifting Appliances' which ensures their ability to cope with the dynamics associated with their intended use. CURRENT CAPABILITY Today it is now widely recognised that the ROV is the primary support system on drilling rigs. Recently, however. we have seen numerous instances where the ROV has been required to perform activities which may be considered beyond the ROV's commonly perceived capabilities. Such projects highlight that ROVs can perform tasks that were previously considered unlikely and will encourage new tasks to be considered with confidence. It also became evident that all work class ROVs do not have equal compatibility and that certain tasks will require the higher specification models to be used.