EFFECT OF FRICTION ON STRUCTURAL CAPACITIES OF A SUBSEA INTERVENTION SYSTEM EQUIPMENT

The offshore oil and gas industry is drilling into and producing from wells in high-pressure, high-temperature (HPHT) environments. This has created a greater demand to develop more advanced tools and new technology to safely overcome the challenges in these operations. Due to the sensitivity and potential impact on the environment, the industry is striving to homogenize the design and acceptance criteria. The API 17G is the industry standard for offshore intervention operations. This standard adopts the methodologies from ASME Boiler Pressure Vessel Code (BPVC) Section VIII, Div. 3. The objective of this study is to evaluate structural capacity of a subsea intervention system equipment according to API 17G standard by utilizing Yielding Load Method for single and combined loads per elastic-plastic analysis with no strain hardening. The assembly has multiple tightly fitted parts that can slip and slide upon application of external loads. Large deformations (nonlinear geometry) shall be included when analyzing such models. Contacts are modeled with friction. Therefore, application of real friction value is important for accuracy of results that are representative of realistic operations. A sensitivity study is conducted to assess the effect of friction on the structural capacity. In addition, absence of through section yielding criterion is also verified.