Technology Challenges in Deep Water Subsea Well Intervention - A focus on Equipment Design Advancements

Abstract

Due to the current challenging environment in Oil and Gas industry, cost effective hydrocarbon recovery from Subsea Wells is mandating innovative methods in equipment design construction and qualification. Different types of intervention systems are required based on the issue being addressed, the intervention technique being used, depth of water, geographical locations, vessel types and pressure/temperature conditions. The industry is increasingly utilizing well access solutions such as Open water riser system and Light Well Intervention System not only for equipment installation, but also to improve efficiency of operations, to facilitate life-of-field hydrocarbon production enhancement and restorative intervention techniques. Suppliers and Operators of subsea intervention system need to rise to the challenge of meeting increasingly stringent industry standards and customer requirements. This necessitates but is not limited to the importance of utilizing effective seal design, robust barrier design, advanced materials and safety rated control systems with rigorous design and qualification test validation.The more demanding requirements of the move to deeper and deeper water and higher pressures and temperatures have led to enormous challenges both at the component and system level. This is driving the incorporation of the latest technology on both metallic and non-metallic seals for high temperature application. This is particularly relevant in valve qualification for field producing hydrocarbons with high levels of sand. Size and weight reduction design strategies for equipment destined to be used in deep water allows for effective selection of existing rigs and vessels of opportunity. Advanced design validation including 3D printing of components has resulted in more accurate and predictable results for Component interactions, Strength Integrity and Fatigue Capacity. Thermal analysis used for prediction has allowed for prevention of hydrate formation which has proved essential to validation of the intervention system performance.To qualify subsea components in deep water, technology enhancements, the latest manufacturing techniques and supply chain approaches, welding techniques etc. are critical to success. Deepwater System challenges include communicating and controlling the well and Xmas tree remotely through an Installation and Workover Control System. This can be resolved with design of optimized safety-rated electro-hydraulic system along with a robust sensor system which provides a safe and reliable method for hydrocarbon containment during critical well intervention operations. This paper will depict some of the latest design techniques required to deliver advanced equipment to the Intervention market. The areas addressed will be: Identification of the technology challenges, providing right solution, usage of design tools for equipment design advancement and managing risk. Reference API 17G -Recommended Practice for Completion/Workover Risers Deep water well intervention and Fluid selection -Merve Dul...