Abstract
The objective of this work is to present a new methodology (called: ‘SafeOP’) for the design of subsea Rigid Jumpers (RJ) to assist the development of EPCI (Engineering, Procurement, Construction, and Installation) projects for submarine interconnection in Brazilian fields based on preliminary field layouts.
The new methodology is based on a more complete parametric study based on the layout of the field where there are limits given by the capacities of the pipes, connectors, or by the resistance of the well XT (Christmas Tree). The proposed flexibility of the arrangement is to analyze all possible configurations of a wellhead Rigid Jumper, between a first end PLET (Pipeline End Termination) and a XT, varying the angle between the Jumper and PLET heading, that is aligned with the Flowline. To be able to cover the spectrum of all connection possibilities between Jumper and Flowline and thus find an envelope for the positioning of the target boxes, which limits this angle according to the proposed geometry.
The results obtained with this methodology demonstrated to be very satisfactory, with great economy in the engineering executed on this type of design package.
The application of the methodology defines the angular limits where the arrangement works for the proposed field layout and thus, it will be possible to give greater flexibility due to the understanding of these limits and maximum angles where the design continues to be valid, even after changing the layout. This performed by simply checking the angle between the structures and updating the arrangement for the new angle and new lengths found.
This methodology is very important considering the detailed design of jumpers in an EPCI project is strongly linked to the geometry of the subsea field layout which may not be available at the early project stage. In addition, the design of the jumper involves interfaces with different project teams for activities, including preparation of specifications, procurement, fabrication, testing, assembly, loading, offshore transport, subsea installation, and commissioning of equipment. At the same time, due to schedule constraints, the design of jumpers cannot be carried out too late in the project, without delaying the interfacing activities.
As part of pre-salt developments offshore Brazil, the field layout may change significantly through the course of the project execution phase, to minimize the associated planning and financial risk for the project, the proposed approach allows decoupling of the rigid jumper design from the local field layout potential changes by defining beforehand associated working envelops for a full range of possible local field layout.
