Page 488 - Pipelines and Risers

Pipe-in-Pipe and Bundle Systems 455

The following conditions shall be analyzed for bundle thermal analysis:

Steady state
The evaluation of bundle steady state thermal performance includes the calculation of U-value
and process fluid properties.

Bundle cool down
The evaluation of bundle cool down thermal performance includes the transferring initial cool
down properties from steady state analysis and calculating the bundle cool down time.

Bundle heat-up
The evaluation of bundle heat-up thermal performance includes the calculation of the process
fluid properties at initial and final heat-up conditions and calculation of the bundle heat-up
time.

The following heat-up system operating parameters have been subject of the design:

0 Maximum heating medium flowrate
Heat-up time
Heat-up system volume

The heat transfer inside the bundle and the bundle heat-up time are dependent on the
following factors:

Bundle configuration and the relative positions of the components
Bundle length
4 Heating medium temperature
Properties of the fluid contained inside the flowlines

243.7 Umbilicals in Bundle
The general functional design requirements for umbilical are as follows:

The level of redundancy shall be the same as for a system with separate umbilicals.
The control system shall be protected during fabrication and testing period.
Testing of the system shall be catered for duringlafter fabrication and duringlafter
installation on the seabed.
0 Seamless tubing, all welded, shall be used.