Characterization and Technical Comparison Between Steel Tube Umbilicals and Thermoplastic Hoses Umbilicals

Subsea umbilicals are key part on the development of deep water fields. Generally, they are used to connect Platforms to all type of subsea equipment. Umbilicals’ component failure may result to great production losses. Traditionally, Petrobras uses thermoplastic hoses for chemical injection and control applications in its subsea systems; it has acquired a great deal of technical knowledge. Nevertheless, in recently presented layouts, the steel tubes have gained importance worldwide and this was due the increased water depth, integrity and higher pressure / higher temperature. This present paper makes a technical comparison between Steel Tube Umbilicals and Thermoplastic Hose Umbilicals with focus on Petrobras experience. The first part analyzes material selection criteria considering each structure type. Subjects such as material, welding and construction of both types are commented. This work also points to important subjects that suppliers must consider when designing and manufacturing umbilicals. The second part presents the Petrobras’ qualification tests of control umbilicals. Some of the tests that are used for steel tubes, thermoplastic hoses and high collapse resistant hoses are listed as well. On the third part, the focuses are the fatigue analysis, installation procedures and corrosion aspects. The work concludes listing some advantages and disadvantages when using Steel Tube Umbilicals or Thermoplastic Hoses Umbilicals, considering Petrobras scenarios.