THE ROLE OF ECA IN THE DEVELOPMENT OF DYNAMIC RISER SYSTEMS

摘要

An Engineering Critical Assessment (ECA) is a procedure that may be used to define and characterise critical flaw sizes from which acceptance criteria for non-destructive examination (NDE) can be developed or confirmed. Dynamic riser systems are fatigue sensitive structures that are commonly regarded as one of the most challenging aspects of a deepwater development. An ECA provides the facility to increase confidence as it develops an understanding of the margin of safety afforded by the derived acceptance criteria based upon variations in extreme and long-term loads, material properties such as fracture toughness, quality standards for welding, control of stress concentration factors and the nature of potential failure. The paper will demonstrate the objectives, adopted methodology and explore the conclusions of an ECA with the aid of examples.