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emergency reasons, it can be performed
quickly. This derives the safety and security
that Petrobras targets.”
As a result of the P23 trial success, RFS was
commissioned in late-2003 to fit out a
further twenty offshore structures: seven
FPSOs, ten semi-submersibles and three fixed
platforms.
Soares and his team immediately surveyed
all twenty structures and assigned an
installation and commissioning crew for the
project. “An important element of this
project was that Petrobras required a total
turnkey approach,” explains RFS Key Account
Manager for Petrobras, Marcus Gama. “This
meant we were not only responsible for
the total RF design and technology supply,
but also for the supply and installation of
the radio basestations, the on-platform
distribution systems and all associated
peripherals. We also took responsibility for the
mobile radio programming, site commissioning
and system performance tests.”
Design of all 20 platform systems was
The installation demanded ‘intrinsically
safe’ radio systems be used—these ensure
that ‘emitted’ electrical energy is kept
below a maximum level, and prevents the
occurrence of any potential spark ignition
sources. Suitable lightning protection was
also essential in the exposed open waters of
the Atlantic. A ten-hour rated UPS backup
was included for the radio system, to
provide support in the event of a platform
power failure. While the initial design scope
was to support a five channel, 450 MHz
analogue system, for reasons of
futureproofing, Petrobras demanded that
the entire system be broadband to 2.4 GHz.
The RFS design team had also to take special
heed of on-platform ‘hazardous area
zoning’ requirements, and particularly the
transition of cable between these zones.
To this end, many room-to-room cable
transitions had to be specially sealed and
fireproofed, using appropriate synthetic
sealing blocks and sealant. The entire
Plan’—achieving 100 per cent RF coverage
of all operations and maintenance points
across the platform.
This was put to the test in late March 2004,
when the first of the twenty upgraded
platforms—an FPSO called P47—was
subjected to System Assessment Testing by
the Petrobras team in its dry dock facility in
the city of Rio de Janeiro. The RF signal
levels easily met the Petrobras-specified
minimum requirement of -70 dBm across
the entire platform, and often clearly
exceeded this level. “This is a 100 per cent
improvement [over the previous system],”
Cumin says. “The operations and maintenance
crews will now have the guarantee
that they will find a well-established
signal to start and receive the communications—quality
communications can now be
achieved anywhere on the platform.”
With the P47 soon destined to leave Rio de
Janeiro and make its way out to the deep
waters of Campos Basin’s Marlim field, the
8 C OVER STORY
An FPSO is a ship fitted out
for drilling, product storage and
long-term at-sea location—pictured
is Petrobras’s P37 in the Marlim oil field.
completed by the RFS Sao Paulo team
during September/October 2003, with
Petrobras-witnessed factory acceptance
testing completed at RFS Sao Paulo.
Installation commenced in November of
the same year, with commissioning of
the systems completed during the first
half of 2004.
Offshore challenges
The project presented the RFS WDCS
design team with a number of technical
challenges—many of them unique to
the offshore platform environment. For
obvious safety reasons, the entire
installation—including feeder cables
and radiating cables—had to be both
flame and fire retardant, and low
smoke producing. This specification was
easily met by RFS RADIAFLEX and
CELLFLEX, as its ‘JFL’ jacket is flame and
fire retardant to IEC 60 332, and
classified ‘low smoke’ in accordance
with IEC 61 034.
installation had to be both corrosion and
vibration resistant, to ensure it survived
the salt-laden atmosphere and platform
vibrations.
System redundancy was also essential.
“The system had to be designed to ensure
optimal reliability,” explains Cumin. “On
the platform there are operationally hazardous
areas—such as the production
deck—where a feeder cable passing over
the area might be at risk from machinery.”
A complete system redundancy plan was
undertaken by RFS in conjunction with
Petrobras. In areas where it was deemed
necessary, RFS deployed redundant feeders,
alternative low-gain back-up antenna
systems, and so on.
New industry standard
But the most important objective of all,
according to Cumin, was realizing
the new industry standard specified in
Petrobras’s ‘Operational & Excellence
remaining 19 platforms in this project are
scheduled for System Assessment Testing
by Petrobras through to mid-2004. In the
latter half of 2004, RFS is scheduled to
commence fitting out a further nine
Petrobras platforms. Once again, this will
be a total turnkey project, with guaranteed
RF coverage on each of the platforms.
The Petrobras 2001 ‘Operational &
Excellence Plan’ set out to realize a new
global standard for deck-to-deck RF
coverage on offshore platforms. As a
renowned leader and innovator in the
sector, this is no new terrain for the oil and
gas giant. “RFS is proud to have played
such a significant role in helping Petrobras
achieve this new standard,” says RFS’s Ron
Dorst. “It’s been an undeniable challenge,
but the success of this project exemplifies
the breadth of our company’s confined
coverage know-how and experience—and
the almost limitless nature of a truly
tailored RF solution”.