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Changing the way you succeed. 1
Cable Burial in Subsea Cables
Who is Canyon Offshore
What have we done in cables outside O&G
What are the seabed conditions that are encountered
What equipment is there to burial cables
Who sets and how do you achieve the DOB required
What happens if you don’t
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Canyon’s Current Trenching Equipment
Our fleet of purpose built trenchers are
available to trench and backfill in water
depths up to 2500m.
Operating in tracked, free fly or pipe follow
mode, along with unique jetting and backfill
tooling, each system can be customised
based on project soil conditions and desired
trench results.
Current fleet consists of 5
Trenchers
i-Trencher – 1725 HP
T1200 – 1200HP
T750 - 750 HP
T600 - 600 HP
T1500 – 1500HP
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Grand Canyon 1, 2 & 3 Trenching Support Vessel
Vessel Overview
DP 3 , Ice Class
Long term charter from Volstad
Purpose built trenching vessel
Clean & Comfort Class
Accommodation for 108 POB
250 MT crane
125m LOA ,beam 26m, deck space 1600 m2
Vessel Spread
Reeled or Carousel lay spread
Jet Trencher (T1200, T1500 or T750)
Heavy Soils Trencher (itrencher)
2 x WROVs
The Grand Canyon is the host vessel to the equipment that form
the Primary Trenching Solution. Since entering service in 2012, it
has acted host vessel on a number of projects on a global
footprint
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Interconnector , Export Cable & Offshore Wind Farm Experience
BritNed - IC
EWIP – IC
NorBolt - IC
Greater Gabbard
Thornton Bank
Sherringham Shoal
London Array
Meerwind
Northwind
Nord See Ost
Borkum West 2
Dan Tysk
Baltic 1 - E
Baltic 2 - E
Borkum Riffgund - E
Dolwin 2 - E
Butendiek – E
Sandbanks - E
WMF Export Ends
Nord See 1 - E
Norrthwind, Belwind, Alstom
Remedial – IA & E
Dudgeon – IA
Galloper – IA
Blyth Demonstrator - IA
CMS – IC 2017
Racebank – E remedial
NSL – IC 2018-2021
Nordlink – IC 2018
Hornsea – IA 2018
Beatrice – IA 2018
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Seabed Conditions
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Tools in the box
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Tool Selection Process – Burial Protection Index
Very Soft
Clay 10 kpa
Firm
Clay 40kpa
Coarse sand
Very Stiff
Clay Fine
sand
Burial P
rote
ctio
n In
de
x
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Mole, P., Featherstone, J. and Winter, S. (1997) Cable
Protection –
Solutions Through New Installation and Burial Approaches.
SubOptic ’97.
Burial Depth (m) 1 2 3
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Soils Overview-Tool Selection and Risk Matrix
During the bids / tender phase complete
full Geotechnical Analysis on data
provided
Work with client to define any areas of
risk and then select tool to achieve
contracted burial depth
Complete Programme of Work in
conjunction with client construction
programme and amended as client more
fully understands his customers
expectations
Submit contractual and Reasonable
Endeavours clauses to meet requirements
of the contract
Complete all engineering, procedures and
survey reporting as required by the client
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Reasonable Endeavours
Why Reasonable? Why Not Best?
used to qualify a schedule and therefore price
to complete a burial operation
Used to mitigate that the survey may not be
representative of the actual conditions found
and therefore it used where Adverse Soil
Conditions are encountered
Limits the use of one tool in favour of another
Limitation of obligation (liability) on the
contractor to perform the works
Excludes certain other remedial protection.
Its NOT a place to hide – old style
protectionism
It is about Risk share and balance
Used extensively in renewables projects
Though some Clients would rather you went
to FIDIC – Silver book
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Thank You
Bringing Past Experience to a Safer Future John Davies
Director Seabed Intervention
Canyon Offshore Ltd
http://www.helixesg.com/canyon/
Helix House, Kirkton Drive, Pitmedden Industrial
Estate, Dyce, Aberdeen, AB21 0BG
Tel: +44 (0)1224 351800
DDI: +44 (0) 1224 755015
Mob: +44 (0) 7971 223383
Fax: +44 (0)1224 351801
Email: [email protected]