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(supported by visits and interviews of eligible
bidders), transportation studies and shipping
arrangement evaluations.
Based on the above-mentioned considerations
the main features of the modular project execu-
tion are summarized in the following.

Engineering
Modularization required accelerated enginee-
ring activities compared with a conventional
approach. Structural design needed to be
fnalized early during the EPC phase to con-
solidate modules shapes and dimensions. As-
Fig. 6 - Towards modularization nes including layout engineers, process engine- sociated material take-off is also requested to
execution plan ers and equipment engineers. evaluate the initial effort of prefabricators.
Other departments comprising procurement, Foundation and underground design incorpo-
HSE and construction also provided contribu- rated not only the static and dynamic loads
tions and ideas. During this period, key modules of equipment but also the crane, temporary
were studied from civil, structural, instrumen- structures and modules transportation requi-
tation, equipment design perspectives. During rements.
reviews (some of them included client repre- Deliverables and drawings have been pro-
sentatives), the modularization team fne-tuned duced on a module-by-module basis, co-
the range of module weights and dimensions, vering one specifc construction area and in
providing the basis for construction and logistics alignment with the assembling schedule. Mo-
strategies. Information was also used to deve- dule boundaries have also been indicated in
lop a preliminary prefabrication yard analysis the general documents such as the overall
plot plan, electrical one-line diagrams, piping
and instrument diagrams, foundation plan (f-
gure 7). Engineering lists (line list, equipment
Deliverables and drawings have list, instrument list etc.) have been integrated
been produced on a module-by- with the module list, indicating the module to
module basis, covering one specifc which the item belongs.
construction area and in alignment with Cable routing and underground facilities have
been designed using duct-bank installation to
the assembling schedule make them independent from module delivery
at site.
Fig. 7 - Modules overview A proper procedure for module weight ma-
nagement and center-of-gravity control has
been prepared to monitor the variations of
these important factors.
Multiple critical paths and sequences have
been considered to keep under control:
- equipment delivery to modularization yard;
- bulk material delivery to modularization yard;
- module delivery at site and module erection
and hook-up.

Procurement
Modularization requires accelerated procure-
ment activities compared with a conventional
approach since the delivery of equipment and
bulk material to the prefabricator is a pre-con-
dition to allow the start of preassembling wor-
ks. Increased coordination is also required to
fnalize the subcontract for module fabrication
in due time and assure the correct sourcing of
materials.
Equipment needs to be ordered 2-3 months

56 56 Impiantistica Italiana - Luglio-Agosto 2014