scope:

The scope of this RP is limited to the following systems:

― open-water intervention riser system (OWIRS);

― through-BOP intervention riser system (TBIRS);

― subsea pumping well intervention system (SPWIS);

― riserless subsea well intervention system (RSWIS).

This RP includes input, output, and analysis as follows:

― data to serve as inputs to global riser analysis;

― modeling techniques, assumptions, and verifications;

― load case matrix;

― operability, weak point, and fatigue analysis;

― analysis outputs and interpretations.

This RP complements the API 17G sub-series documents (e.g., API 17G1,17G5) as applicable for the system scopes listed above that identify the information required to conduct the analysis (inputs) and interpret the results of the analysis (outputs) to determine the system operating limits. Different global riser modeling techniques and assumptions are presented for consideration by the user. To increase user awareness, discussion of modeling techniques focuses on parameters that drive riser response, as well as typical areas of concern. The techniques proposed herein are considered best practices and serve as analysis guidance. Where possible, this document refers to existing industry standards and practices to avoid duplication while addressing the key issues facing workover/intervention GRA.

This RP outlines a detailed load case matrix for a GRA of a subsea well intervention system. The user may decide to modify the scope of work (or a subset of this matrix) deemed essential to meet project requirements in agreement with the operator, service contractor, and regulatory bodies. The load case matrix encompasses anticipated operational scenarios; however, additional nonstandard cases may need to be assessed.

This RP also outlines typical GRA outputs and provides guidance on their interpretation, including guidance on mitigations and examples.

This RP does not assess fatigue performance of the well system.