ROV Tooling and Interface Design for a Subsea Satellite Template

Abstract

ABSTRACT This paper describes the ROV intervention tooling and interface designs for the Troll Osberg Gas Injection (TOGI) template. The ROV tooling and interface hardware successfully completed shallow water tests in January 1989 and are presently undergoing final integration testing. The paper is significant because the TOGI template is the deepest underwater production template ever installed in the North Sea. The template's dependence on cost effective and efficient ROV support has caused an increase in the level and sophistication of ROV tasks and hardware and these advances are applicable to many other deep water installations. INTRODUCTION Production systems are being installed in deeper waters than ever before and are requiring more unmanned intervention. In addition, production systems are becoming more sophisticated. These two factors are combining to expand the envelope of present remote subsea support, intervention tasks and hardware. The TOGI project represents an up-to-date example of present day ROV production intervention capabilities. The TOGI ROV work packages are designed to be ROV independent so that they can be deployed and operated by work ROV's of opportunity. In order to accomplish this, the ROV tools are powered and controlled through a modular hydraulic power skid package, and the deployment of the tools is based on the fly-in method. The use of manipulators is minimized and all tool interfacing is done through the hydraulic power skid as shown in Figures 1 & 2. TOOL DEPLOYMENT/DOCKING Many previous remote work system tooling and work package designs relied on manipulator installation of the tools. Manipulators are necessary and useful tools for performing a wide variety of subsea work tasks. However, different manipulators have different operational envelopes and characteristics and it is extremely difficult to develop manipulator deployed tools that are manipulator/remote work system independent. At the same time, it is usually impossible to justify the complexity and expense of developing all remote work system interfaces and intervention hardware such that the need for manipulators is eliminated. For this reason, the TOGI remote work system tooling and production equipment interfaces were designed to provide both docking and actuation of various hydraulic and mechanical functions without the use of manipulators, while the operation of hydraulic isolation valves and the connection of surface hotlines were retained as manipulator tasks. In order to ensure the manipulator based tasks could be accomplished by a variety of remote work systems, several full scale manipulator models were built to ensure that compatibility was maintained. The use of the models to determine final equipment location and physical interface design has been proven to be extremely beneficial. As stated above, the best method of ROV tool deployment, in most cases, is by physically flying the tool into position with the ROV. This is commonly referred to as docking.