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Subsea Cable Protection Systems by First Subsea | 5 Essential Articles
September 17th, 2019
Subsea Cable Protection Systems
♦ Republished by Chris Dodds with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)
First Subsea are the world’s leading developer of subsea cable protection systems and connection technology; supplying, installing and decommissioning.
Thorne & Derrick are pleased and privileged to have the permission from First Subsea to republish the following information:
- Subsea Cable Protection Systems Installed On Offshore Wind Farm | Part 1 of 5
- Subsea Cable Protection & Laying Costs | Part 2 of 5
- Subsea Cable Protection Systems – Disconnection & Removal | Part 3 of 5
- Subsea Cable Protection Systems, Damage Prevention & Fixed WTG | Part 4 of 5
- Subsea Cable Protection Systems Design For Installation | Part 5 of 5
Subsea Cable Protection Systems By First Subsea & Thorne & Derrick
T&D are Specialist Distributors to the UK and international Offshore Wind industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.
We provide expert technical support and supply from a multi-million pound stock holding:
| Cable Joints, Terminations & Connectors | Earthing & Lightning Protection |
| Cable Accessories, Lugs & Glands | Circuit Protection & Fuses |
| Cable Cleats & Clamps | Electrical Safety Equipment |
| Cable Pulling & Laying Equipment | Arc Flash Clothing & Protection |
| Cable Duct Seals & Transit Systems | Surge Arresters & Bushings |
We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.
Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.
See how T&D support, supply and service the Renewable Energy industry.
Subsea Cable Protection Systems Design For Installation | Part 5 of 5
September 17th, 2019Subsea Cable Protection Systems
♦ Republished by Chris Dodds with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)
First Subsea is the world’s leading developer of subsea connection technology, supplying, installing and decommissioning.
Subsea power cables on offshore wind farms are typically protected by means of burial.
This is a well proven means of cable protection used in other offshore industries.
However, at either end of offshore wind array cables they transition from burial, up through the water and into the wind turbine foundation. This free spanning section of cable is susceptible to what can be substantial wave and current loads.
These loads introduce movement and bending into the subsea cable which, without cable protection, can lead to over-bending, over-tensioning, fatigue and abrasion damage.
This exposed subsea cable is traditionally ‘protected’ by means of a relatively expensive and complex proprietary Cable Protection System (CPS).
Our 5th Article on Subsea Cable Protection Systems looks at design for installation of subsea cables.
It has been documented by insurance companies and underwriters, such as Allianz and GCube Insurance Services, Inc that “subsea cables cause about 70-80% of losses in terms of overall claims amount incurred.”
These claims have included, freak incidents during transportation, manufacturing faults and damage caused by anchors and construction vessels.
In a paper published by Offshore Renewable Energy Catapult last September, a total of 43 array cable and export failures had been reported since 2007, with manufacturing and installation cited to be the most common cause of cable failure in subsea installations.
CPS design should not only consider protection of the cable during the lifespan of the OWF but it should also provide protection during installation, ensuring handling methodologies offshore do not stress the cable or exceed the cable MBR which can lead to premature failure.
First Subsea have addressed these issues by performing a series of special testing programs using their Tensile Bend Test rig, which simulates the installation loads seen offshore, including the function of the quadrant used in second end pull in. The photo below shows the offshore scenario and the onshore simulated test.
➡ If you would like a copy of the report, please contact Chris Dodds [email protected]
- Subsea Cable Protection Systems Installed On Offshore Wind Farm | Part 1 of 5
- Subsea Cable Protection & Laying Costs | Part 2 of 5
- Subsea Cable Protection Systems – Disconnection & Removal | Part 3 of 5
- Subsea Cable Protection Systems, Damage Prevention & Fixed WTG | Part 4 of 5
LV, MV & HV CABLE JOINTING, EARTHING, SUBSTATION & ELECTRICAL EQPT
Thorne & Derrick are Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.
We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.
Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.
t: 0191 410 4292 | e: [email protected] | www.powerandcables.com
We provide expert technical support and supply from a multi-million pound stock holding:
- Cable Joints, Terminations & Connectors Earthing & Lightning Protection
- Cable Accessories – Lugs, Glands
- Circuit Protection & Fuses
- Cable Cleats & Clamps Electrical Safety Equipment
- Cable Pulling & Laying Equipment
- Arc Flash Protection & Clothing
- Cable Duct Seals & Transit Systems Surge Arresters & Bushings
Further Reading:
- Arc Flash Clothing & Protection For Safe Windfarm & Wind Turbine Working
- Jointer Training Courses – 11kV 33kV 66kV MV HV Cable Jointer Competency Training
- Sealing Cables In Offshore Substations – A Roxtec CPD
Subsea Cable Protection Systems, Damage Prevention & Fixed WTG | Part 4 of 5
September 17th, 2019Subsea Cable Protection Systems
♦ Republished by Chris Dodds with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)
First Subsea is the world’s leading developer of subsea connection technology, supplying, installing and decommissioning.
Subsea power cables on offshore wind farms are typically protected by means of burial.
This is a well proven means of cable protection used in other offshore industries.
However, at either end of offshore wind array cables they transition from burial, up through the water and into the wind turbine foundation. This free spanning section of cable is susceptible to what can be substantial wave and current loads.
These loads introduce movement and bending into the subsea cable which, without cable protection, can lead to over-bending, over-tensioning, fatigue and abrasion damage.
This exposed subsea cable is traditionally ‘protected’ by means of a relatively expensive and complex proprietary Cable Protection System (CPS).
Our 4th Article on Subsea Cable Protection Systems looks at why we need them for fixed wind turbine generators (WTG).
When First Subsea enteredthe renewable market we wanted to ask the simple question – Do we need subsea cable protection at all?
We had seen that traditional Cable Protection System (CPS) utilised bend restrictors which are designed to prevent overbending of subsea cables and from our studies we identified this would not occur in most projects. Restrictors also introduced additional loading to the subsea power cable due to hydrodynamic drag and increased inertia.
This in fact increased the risk of cable damage and reduced the inherent cable fatigue life.
This led us to reasoning why put a restrictor based CPS on at all if it reduces your cable life?
What Do You Think?
The study did identify that subsea medium/high voltage power cables cannot be left unprotected.
There is still a risk of cable damage due to Fatigue where the cable exits the foundation interface and Abrasion and Foreign body impacts.
These risks should be mitigated with a CPS optimised to protect against these types of damages. An optimised CPS design using stiffening elements like Bend Stiffeners and tubes will reduce the risk of subsea cable damage, including fatigue over the life of the wind farm.
➡ If you would like a copy of the report, please contact Chris Dodds [email protected]
- Subsea Cable Protection Systems Installed On Offshore Wind Farm | Part 1 of 5
- Subsea Cable Protection & Laying Costs | Part 2 of 5
- Subsea Cable Protection Systems – Disconnection & Removal | Part 3 of 5
- Subsea Cable Protection Systems Design For Installation | Part 5 of 5
LV, MV & HV CABLE JOINTING, EARTHING, SUBSTATION & ELECTRICAL EQPT
Thorne & Derrick are Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.
We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.
Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.
t: 0191 410 4292 | e: [email protected] | www.powerandcables.com
We provide expert technical support and supply from a multi-million pound stock holding:
- Cable Joints, Terminations & Connectors Earthing & Lightning Protection
- Cable Accessories – Lugs, Glands
- Circuit Protection & Fuses
- Cable Cleats & Clamps Electrical Safety Equipment
- Cable Pulling & Laying Equipment
- Arc Flash Protection & Clothing
- Cable Duct Seals & Transit Systems Surge Arresters & Bushings
Further Reading:
- Arc Flash Clothing & Protection For Safe Windfarm & Wind Turbine Working
- Jointer Training Courses – 11kV 33kV 66kV MV HV Cable Jointer Competency Training
- Sealing Cables In Offshore Substations – A Roxtec CPD
Subsea Cable Protection Systems – Disconnection & Removal | Part 3 of 5
September 16th, 2019Subsea Cable Protection Systems
♦ Republished by Chris Dodds with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)
First Subsea is the world’s leading developer of subsea connection technology, supplying, installing and decommissioning.
Subsea power cables on offshore wind farms are typically protected by means of burial.
This is a well proven means of cable protection used in other offshore industries.
However, at either end of offshore wind array cables they transition from burial, up through the water and into the wind turbine foundation. This free spanning section of cable is susceptible to what can be substantial wave and current loads.
These loads introduce movement and bending into the subsea cable which, without cable protection, can lead to over-bending, over-tensioning, fatigue and abrasion damage.
This exposed subsea cable is traditionally ‘protected’ by means of a relatively expensive and complex proprietary Cable Protection System (CPS).
Our 3rd Article on Cable Protection Systems looks at how subsea cables can be disconnected and removed, focusing on removal times and costs.
Disconnection of the CPS is not a regular occurrence offshore, after a successful installation there should be little reason to disconnect unless the system has experienced accidental damage, premature failure due to design, manufacture or higher than expected loading.
Problems during installation may require disconnection, such as, pinch points in I-Tube, winch capacity exceeded due to friction losses, incorrectly sized pull-in accessories and obstructions in entry holes.
A common misconception is the CPS is removed if the cable is faulty. Typically, the cable is disconnected and passed back through the system and the new cable is threaded back.
First Subsea CPS is a proven removable system. In a recent project an installation issue occurred that required the CPS to be removed. The disconnection process, remedial work and re-connection took less than 12 hours.
Quite some time you may think, but when you consider alternative systems require removal by subsea sawing or risk damaging the structure when removing. First Subsea CPS will save minimum €40,000 vessel, diving/ROV time. Client “it was an invaluable feature that got us out of a bind”
➡ If you would like a copy of the report, please contact Chris Dodds [email protected]
- Subsea Cable Protection Systems Installed On Offshore Wind Farm | Part 1 of 5
- Subsea Cable Protection & Laying Costs | Part 2 of 5
- Subsea Cable Protection Systems, Damage Prevention & Fixed WTG | Part 4 of 5
- Subsea Cable Protection Systems Design For Installation | Part 5 of 5
LV, MV & HV CABLE JOINTING, EARTHING, SUBSTATION & ELECTRICAL EQPT
Thorne & Derrick are Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.
We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.
Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.
t: 0191 410 4292 | e: [email protected] | www.powerandcables.com
We provide expert technical support and supply from a multi-million pound stock holding:
- Cable Joints, Terminations & Connectors Earthing & Lightning Protection
- Cable Accessories – Lugs, Glands
- Circuit Protection & Fuses
- Cable Cleats & Clamps Electrical Safety Equipment
- Cable Pulling & Laying Equipment
- Arc Flash Protection & Clothing
- Cable Duct Seals & Transit Systems Surge Arresters & Bushings
Further Reading:
- Arc Flash Clothing & Protection For Safe Windfarm & Wind Turbine Working
- Jointer Training Courses – 11kV 33kV 66kV MV HV Cable Jointer Competency Training
- Sealing Cables In Offshore Substations – A Roxtec CPD
Subsea Cable Protection & Laying Costs | Part 2 of 5
September 16th, 2019Subsea Cable Protection Systems
♦ Republished by Chris Dodds with Kind Permission of Greg Campbell-Smith ((Director Sales and Business Development at First Subsea)
First Subsea is the world’s leading developer of subsea connection technology, supplying, installing and decommissioning.
Subsea power cables on offshore wind farms are typically protected by means of burial.
This is a well proven means of cable protection used in other offshore industries.
However, at either end of offshore wind array cables they transition from burial, up through the water and into the wind turbine foundation. This free spanning section of cable is susceptible to what can be substantial wave and current loads.
These loads introduce movement and bending into the subsea cable which, without cable protection, can lead to over-bending, over-tensioning, fatigue and abrasion damage.
This exposed subsea cable is traditionally ‘protected’ by means of a relatively expensive and complex proprietary Cable Protection System (CPS).
Our 2nd Article on Subsea Cable Protection Systems focuses on Subsea Cable Protection & Laying Costs.
As part of our product awareness feature on Cable Protection Systems we look at the time taken to install, focusing on the critical path timings, that impact on the installation costs.
Cable lay construction vessels command market rates in excess of €150,000 a day, due to their ability to reel, carry and deploy cable using dynamic positioning, this figure excludes crew/fuel.
Most large cable lay vessels have the ability to pre-assemble and prepare the cable protection system on the runway off the critical path as they perform other operations, so the deck preparation times which take on average an hour have been discounted.
The critical path clock for the CPS product starts as it is deployed over the chute located at the stern of the vessel. The graph shown below shows the times for a number of cable pull ins with a crew new to our system. Our quickest time was 38 minutes from overboarding to connection.
After the first few pull-ins the team averaged 45 mins. From first hand observations on another CPS we saved over an 1hr on critical path.
Saving an hour on critical path, could provide a saving of €7,000, small change you may think. Think again Typically 150 CPS per project could save over €1,000.000 When selecting CPS consider the overall CAPEX not just the product cost.
➡ If you would like a copy of the report, please contact Chris Dodds [email protected]
- Subsea Cable Protection Systems Installed On Offshore Wind Farm | Part 1 of 5
- Subsea Cable Protection Systems – Disconnection & Removal | Part 3 of 5
- Subsea Cable Protection Systems, Damage Prevention & Fixed WTG | Part 4 of 5
- Subsea Cable Protection Systems Design For Installation | Part 5 of 5
LV, MV & HV CABLE JOINTING, EARTHING, SUBSTATION & ELECTRICAL EQPT
Thorne & Derrick are Specialist Distributors to the UK and international Offshore Wind & Renewable industry to provide safe and reliable LV HV Electrical Cable & Power Distribution Systems – we are highly customer responsive and absolutely committed to providing a world-class service.
We have an International Distribution Agreement with Nexans Power Accessories UK to supply their Heat Shrink and Cold Applied ranges of 11kV/33kV/66kV joints and terminations and Euromold brand of separable connectors.
Since 1985, we have established an international reputation based on Service, Integrity and Trust – contact us.
t: 0191 410 4292 | e: [email protected] | www.powerandcables.com
We provide expert technical support and supply from a multi-million pound stock holding:
- Cable Joints, Terminations & Connectors Earthing & Lightning Protection
- Cable Accessories – Lugs, Glands
- Circuit Protection & Fuses
- Cable Cleats & Clamps Electrical Safety Equipment
- Cable Pulling & Laying Equipment
- Arc Flash Protection & Clothing
- Cable Duct Seals & Transit Systems Surge Arresters & Bushings
Further Reading:
- Arc Flash Clothing & Protection For Safe Windfarm & Wind Turbine Working
- Jointer Training Courses – 11kV 33kV 66kV MV HV Cable Jointer Competency Training
- Sealing Cables In Offshore Substations – A Roxtec CPD
