Tube Products International March 2015

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March 2015 Tube Products International 69
Cortez Subsea Ltd – UK
The linear separation between the Zap-Lok press
and the tensioner has a direct effect on the lay
rate of the system.
A longer back deck area and a greater separation
between the Zap-Lok press and the tensioner will
mean that there can be several connected joints
between the Zap-Lok press and the tensioner,
therefore allowing some of the Zapoxy curing
time period to be brought offline, and the lay rate
increased.
The standard MPS stinger has been designed
to accommodate the largest anticipated loads,
but is adjustable in length such that it can be
shortened if required, depending on product and
water depth. The abandonment and recovery
winch is used in the same way as for traditional
pipelay methods, and is used for controlled
laydown and recovery of pipe.
The MPS system comes with its own electrical generators,
hydraulic HPUs and compressed air supplies to run the
system independently of the host vessel.
Installation and removal
“The MPS has been designed using similar sized structural
components, with similar types of bolted connections. All
the component parts have been design to be road or sea
transportable and fit within standard freight dimensions,”
explained Mr Cowie.
“The assembly of the component parts has also been
considered and the number of connections to be made has
been minimised.
“All structural foundations are based on similar sized beams,
meaning that the sea-fastening design is standardised, and
the overall dimensions of the foundations are designed such
that they span the required number of ‘hard points’ on a
typical deck to achieve the required values.”
Cortez Subsea says that individual component items, eg
pipe storage racks, can be assembled on the quayside prior
to the host vessel arrival and then lifted on as assembled
units. Larger items such as the Zap-Lok press, tensioner(s)
and A&R winches are bolted down onto bespoke bases that
form part of the MPS firing line foundation.
For demobilisation, the process is reversed with the focus on
getting the vessel off hire and available for other work. The
major items are stripped back to their component parts for
storage or shipment.
“What makes this unique is that the mechanical interface
joint is considerably quicker than the reeling process, which
involves pre-welding on shore,” added Mr Cowie. “It’s also
a safer option as there is no welding carried out offshore, so
fewer personnel are required on board. You also have better
control over the pipe’s alignment dimensions with this system
as it is cold-worked, and moreover since it is essentially a
manufactured joint.
“Most subsea development costs are increasing, which can
jeopardise future development or replacement projects. By
having the equipment needed for the pipelaying task designed
to be installed and operated from a vessel of opportunity
rather than hiring a specialist pipelay ship, the savings to
an operator are eye-catching and marginal subsea projects
may be able to achieve the required financial targets to gain
sanction.
“We can do the engineering analysis, carry out the work and
then allow the contractor to tie the pipeline in and complete
the commissioning. All you need is a DP2 vessel around 100m
long.
“Three of the major international operators and numerous
independents have approved the use of Zap-Lok for global
subsea operations in the past two years. Operators need to
make tiebacks and completions cheaper in the North Sea, and
using Zap-Lok is a great solution. These organisations see
the obvious advantages of the Zap-Lok technology. We are
now progressing towards fabrication and trials of the first of
the MPS units for operations. This is a significant step in the
development of our company towards advancing technology
and maximising value for the subsea market.”
Zap-Lok pipe connection system