Mechanics Research On Carcass Processing Of Deepwater Flexible Pipe

Energy development is an important industry that influences national security and economic development. The large sea world contains lots of oil and gas resources. Along with the development of marine technology, the exploitation of oil and gas goes from offshore to onshore and gets further and deeper. Floating production system is a common form of deep water oil and gas exploitation. Flexible pipe is an indispensable medium conveying equipment of floating production system, which is composed of multilayer. The most inner layer is called carcass layer, the structure of which is S form stainless steel interlocked. The carcass layer si designed to resist external pressure, which is the key value for pipe used in deep water. The carcass layer is limited by 2 problems:First is the predicting of the complicated structure’s Crushing behavior. Second is the growing thickness making the carcass layer hard to process. Based on the above, supported by the State Hi-Tech Research and Development Program (2012AA09A212), this article studies on the mechanics problems of the processing of carcass layer in deep water flexible pipe.Firstly, the article summarizes the current situation of the development of the carcass layer of flexible pipe, including the research on the crushing behavior of carcass, as well as the present situation of manufacturing of carcass layer in domestic and foreign flexible pipe industry. The article also summarizes the research and development of cold forming technology for the processing of carcass layer. Secondly, a simple mechanics model of carcass layer is analyzed, and a preliminary design is proposed considering the cold forming technology. Then a material test and a component test are carried out to get the material property and to verify the FEM model. Supported by the test, a series of simple ABAQUS model are built up to analysis the relevant parameters. At last, based on the parameters, a whole cold forming model is built up to simulate the processing of carcass. The research give a lot of support on the flexible pipe industry and the crush analysis of carcass.