Rotech Brochure (draft)

Page 1

Trenching and excavation specialists since 1994
www.rotech.co.uk subseainfo@rotech.co.uk 01224 698698 TRS1 TRS2 TRS1-LD RS2-3 RS1LD-3 RS1 RS2 RS1LD RS1-3 RSGC RSG RSBGTRS2 Blade • Cable / Pipeline / Umbilical Trenching • Cable / Pipeline / Umbilical Deburial • Freespan & Sandwave Clearance • Backfilling and Burial • Jack Up Spud Can Clearing & Cleaning • UXO & Salvage Deburial • Rock Dump & Drill Cutting Removal • Harbour Clearance • Subsea Structure Foundation Access • Freespan Rectification • Debris Removal • Boulder Removal/Relocation Work • Cable Cutting and/or Recovery • Umbilical Cutting and/or Recovery • Pipeline Recovery • Rock Removal/Relocation • Seabed Remedial Works • Pre-Sweeping Shallow Water Our Tools

Cable / Pipeline / Umbilical Trenching - Cable / Pipeline / Umbilical Deburial - Freespan & Sandwave Clearance - Backfilling and Burial - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial

Rock Dump & Drill Cutting Removal

Harbour Clearance

Subsea Structure Foundation Access

Safer non-contact methods

Controlled & Mass Flow Excavation

Highly qualified & experienced operators

Real time sonar monitoring of service

Rotech Engineering & Fabrication

pending

Max Jet Flow 1,700L/s

Max Jet Pressure 80kPa

Max Jet Power 85kW

Minimum Operating Depth 2.5m

6 Rotech operators for 24hr operations

2 additional Rotech operators are supplied to operate the jetting system for soils in excess of 80kPa

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk -
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Applications ServicesPersonnel RS1 Controlled flow excavation system patents
Capabilities

TRS1

Controlled flow excavation system

Applications

Cable

Cable

Freespan

Up Spud

Dump

patents pending

Capabilities

Max Jet Flow 3,400L/s

Max Jet Pressure 80kPa

Max Jet Power 170kW

Minimum Operating Depth 2.5m

Services

Personnel

operators for

operations

operators

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk -
/ Pipeline / Umbilical Trenching -
/ Pipeline / Umbilical Deburial -
& Sandwave Clearance - Backfilling and Burial - Jack
Can Clearing & Cleaning - UXO & Salvage Deburial - Rock
& Drill Cutting Removal - Harbour Clearance - Subsea Structure Foundation Access - Safer non-contact methods - Controlled & Mass Flow Excavation - Highly qualified & experienced operators - Real time sonar monitoring of service - Rotech Engineering & Fabrication - 6 Rotech
24hr
- 2 additional Rotech
are supplied to operate the jetting system for soils in excess of 80kPa

Hybrid jet trenching system

Applications

Cable/Pipeline/Umbilical Trenching

Cable/Pipeline/Umbilical Deburial - Freespan rectification

Backfilling & Burial

Jack up Spud Can Clearing & Cleaning

UXO & Salvage Deburial

Rock Dump & Drill Cutting Removal

Harbour Clearance

Subsea Structure deburial and access

Capabilities

Max RS1 Jet Outlet Pressure 80kPa

Max RS3 Jet Outlet Pressure 300kPa

Max RS1 Jet Flow 1,700 L/s

Max RS3 Jet Flow 300 L/s

Operating Depth 2.5m-300m*

Services

Safer non-contact methods

Jet trenching solution for cohesive and non cohesive soils

Highly qualified & experienced operators

Real time sonar monitoring of service

Personnel

6 operators for 24hr operations

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk RS1-3
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RS1-LD

patents pending

Applications

- Ultra Shallow Water - Cable / Pipeline / Umbilical Trenching - Cable / Pipeline / Umbilical Deburial - Freespan & Sandwave Clearance - Backfilling and Burial - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal - Harbour Clearance - Subsea Structure Foundation Access

Services

Safer non-contact methods

Jet Trenching - Controlled & Mass Flow Excavation

Highly qualified & experienced operators

Real time sonar monitoring of service - Rotech Engineering & Fabrication

Capabilities

Max Jet Flow 1,300L/s

Max Jet Pressure 140kPa

Max Jet Power 145kW

Minimum Operating Depth 1m

Personnel

Rotech operators for 24hr operations

additional Rotech operators are supplied

operate the jetting system for soils in excess

140kPa

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk
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Jet trencher

TRS1-LD

patents pending

Applications

- Ultra Shallow Water - Cable / Pipeline / Umbilical Trenching - Cable / Pipeline / Umbilical Deburial - Freespan & Sandwave Clearance - Backfilling and Burial - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal

Harbour Clearance

Subsea Structure Foundation

Services

Safer non-contact methods

Jet Trenching

Controlled & Mass Flow Excavation

Highly qualified & experienced operators

Real time sonar monitoring of service - Rotech Engineering & Fabrication

Capabilities

Max Jet Flow 2,600L/s

Max Jet Pressure 140kPa

Max Jet Power 290kW

Minimum Operating Depth 1m

Personnel

6 Rotech operators for 24hr operations

2 additional Rotech operators are supplied to operate the jetting system for soils in excess of 140kPa

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk
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Jet trencher

Applications

Hybrid jet trenching system - Cable/Pipeline/Umbilical Trenching - Cable/Pipeline/Umbilical Deburial - Freespan Rectification - Backfilling & Burial - Jack up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal - Harbour Clearance - Subsea Structure deburial and access

Capabilities

Max RS1LD Jet Outlet Pressure 140kPa

Max RS3 Jet Outlet Pressure 300kPa

Max RS1LD Jet Flow 1,300 L/s

Max RS3 Jet Flow 300 L/s

Operating Depth 2m-300m*

Services

Safer non-contact methods

Jet trenching solution for cohesive and noncohesive soils - Highly qualified & experienced operators

Real time sonar monitoring of service

Personnel

- 6 operators for 24hr operations

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk RS1LD-3
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patents pending

Applications

Controlled flow excavation system - Decommissioning - Shallow Water - Cable / Pipeline / Umbilical Trenching - Cable / Pipeline / Umbilical Deburial - Freespan & Sandwave Clearance - Backfilling and Burial - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal - Harbour Clearance - Subsea Structure Foundation Access - Safer non-contact methods - Controlled & Mass Flow Excavation - Highly qualified & experienced operators - Real time sonar monitoring of service - Rotech Engineering & Fabrication

Capabilities Services

Max Jet Flow 4,000L/s

Max Jet Pressure 60kPa

Max Jet Power 130kW

Minimum Operating Depth 1.5m

Personnel

- 6 Rotech operators for 24hr operations

2 additional Rotech operators are supplied to operate the jetting system for soils in excess of 60kPa

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk
RS2
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system

patents pending

Applications

Capabilities Services

Max Jet Flow 8,000L/s

Max Jet Pressure 60kPa

Jet Power 260kW

Minimum Operating Depth 1.5m

Personnel

operators

operations

operators

system for

in

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk - Decommissioning - Shallow Water - Cable / Pipeline / Umbilical Trenching - Cable / Pipeline / Umbilical Deburial - Freespan & Sandwave Clearance - Backfilling and Burial - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal - Harbour Clearance - Subsea Structure Foundation Access - Safer non-contact methods - Controlled & Mass Flow Excavation - Highly qualified & experienced operators - Real time sonar monitoring of service - Rotech Engineering & Fabrication - 6 Rotech
for 24hr
- 2 additional Rotech
are supplied to operate the jetting
soils
excess of 60kPa
TRS2 Controlled flow excavation
Max

Hybrid jet trenching system

Applications

- Cable/Pipeline/Umbilical Trenching - Cable/Pipeline/Umbilical Deburial - Freespan Rectification - Backfilling & Burial - Sandwave Removal - Jack Up Spud Can Clearing & Cleaning - UXO & Salvage Deburial - Rock Dump & Drill Cutting Removal - Harbour Clearance

Subsea Structure Deburial and Access

Capabilities

Max RS2 Jet Outlet Pressure 60kPa

Max RS3 Jet Outlet Pressure 300kPa

Max RS2 Jet Flow 4000 L/s

Max RS3 Jet Flow 300 L/s

Operating Depth 3m-300m*

Services

Safer non-contact methods

Jet trenching solution for cohesive and non cohesive soils

Highly qualified & experienced operators

Real time sonar monitoring of service

Personnel

6 operators for 24hr operations

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk RS2-3
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TRS2

Applications

Seabed Remedial Works - Sandwave Clearance - Pre-Sweeping - Shallow Water - Jack Up Spud Can Clearing & Cleaning - Harbour Clearance

Subsea Structure Foundation Access

Capabilities

Max Jet Flow 5,500L/s

Max Jet Pressure 40kPa

Width of Jet 4m

Minimum Operating Depth 1.5m

Services

Safer non-contact methods

Controlled & Mass Flow Excavation

Highly qualified & experienced operators

Real time sonar monitoring of service

Personnel

Rotech operators for 24hr operations

additional Rotech operators are supplied

operate the jetting system for soils in

of 40kPa

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk -
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Blade Controlled flow excavation

Applications

Capabilities

Arm

What’s Included

Personnel

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk RSBG Orange Peel Grab - Debris Removal - Boulder Removal/Relocation Works - Can be configured for ROV hydraulic supply - Optional 2x ROV hot stab connections - Grab transit/Vessel sea-fastening frame - Operating manual - Industry standard ¾” wing type hydraulic connectors - Single leg sling and masterlink supplied for deployment - Grab can be operated by a standard HPU and powered umbilical reel - 2 operators for 24hr operations
Capacity 3.0 m³ Payload 15 Te Weight 4800 kg No. of arms 5 Pressure 200 Bar Flow 40-110 l/min Height Open 3500 mm Height Closed 2800 mm Width Open 2620 mm Width Closed 3680/4040 mm

- Cable Cutting and/or Recovery - Umbilical Cutting and/or Recovery - Pipeline Recovery - Rock Removal/Relocation - Cutting of Cable/Umbilical up to 260mm - Cutting of Wire Rope up to 8”

Capabilities

Max flow 70l/min

Max pressure 350 Bar

SWL (Vertical)

SWL (Horizontal)

Maximum grip force 50kN

Minimum grab diameter 50mm

Maximum grab diameter 1,100mm

Operating Depth

Services

Applications Personnel

- Various Guillotine Cutters available for different products.

- Real Time Sonar Monitoring for locating product - Subsea Camera and Lights

2 operators for 24hr operations

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk RSG-C Rotech
Subsea Grab Tool with Integrated Cutter
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12Te
5Te
0-200m

Applications

Capabilities

Operating Depth

Flow

Maximum Pressure

SWL

Maximum Grip Force

Minimum Grab Diameter

Maximum Grab Diameter

Bar

Services

Personnel

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk - Cable Recovery - Umbilical Recovery - Pipeline Recovery - Rock Removal/Relocation - Real-time sonar monitoring for locating product - Subsea camera and lights - 2 Operators for 12hr operations - 4 Operators for 24hr operations
0-200m Maximum
70l/min
350
(Vertical) 20Te SWL (Horizontal) 5Te
50kN
50mm
1,100mm
RSG Rotech Subsea Grab Tool

TRS1LD - Jan De Nul

TRS1LD - Post-Lay Cable Trenching

Q2,Q3 2020 - Willem De Vlamingh & Grand Canyon II and Cable Routes

Rotech Subsea were contracted by Jan De Nul to provide the TRS1LD Jet Trenching tool to carry out Post-Lay Trenching works on OWF in Taiwan. The scope of work consisited of burying a total of 21 cables (4 Export, 17 Array) to client specification of 2.0m DoL. The project will be completed in 2 phases.

The TRS1LD was selected by Jan De Nul due to its unparallelled technical and performance capabilities resulting in increased productivity and a reduction on the projects total costs. The subsea spread of equipment was mobilised on the Willem De Vlamingh as well as being mobilised on the Grand Canyon II and deployed using the ships crane. Water Depths ranged from 8.0m - 29.0m LAT.

Phase 1 of the project was a success with 4 Export Cables and 7 Array cables being buried to client specification with ease. Soil conditions were described as soft sands however, we experienced large sections of stiff clay with shear strengths up to 80kPa. Despite this, the TRS1LD excelled and still achieved Jan De Nuls burial specifications. The TRS1LD lowered the cable with 2 passes at an average rate of 4m/min and reaching speeds of up to 10m/min in some sections.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY

TRS1 - Post-Lay Umbilical Trenching Q1, 2021 - TRS1 Deployment on the Seven Eagle & TRS1 during Subsea Operations

Rotech Subsea were contracted by Subsea 7 to provide the TRS1 Jet Trenching tool to carry out Post-Lay Trenching works in Offshore Australia. The scope of work consisited of burying 6000m of 118mm diameter umbilical, to client specification of 0.6m Top of Cable.

The subsea spread of equipment was mobilised in January 2021 on the Seven Eagle and was deployed using the vessel crane. The TRS1 was operated in water depths up to 50m LAT, experiencing soil conditions of medium to coarse grained sand as well as harder, more cohesive soils.

The project was a great sucess with Subsea 7 delighted in the TRS1’s technical and performance capabilities. The umbilical was easily trenched to client specification with the Rotech Equipment being operational for only 22 hours for the entire proejct. In the soft soil areas, a trench depth between 1.3m - 1.6m BOT was achieved at a progress rate of 4m/ min. In the harder areas, depths betwen 1.0m - 1.3m BOT were observed at a progress rate of 3m/min. These depths were all achieved with only 1 Pass.

The TRS1’s unparalled capabilities allows for excellent productivity thus leading to a reduction on the projects total costs. A successful project for all parties, and Rotech Subsea look forward to future collaborations with Subsea 7.

Reference

Alex Cliffrod, Senior Project Engineer, Subsea 7

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY TRS1 - Subsea 7

FPOC/Flexible/Umbilical Post Lay Jet

Rotech Subsea Ltd were contracted by SAIPEM as part of a Power-Fibre Optic Cable (PFOC) and Flexible and umbilical Post Lay Jet Trenching Project. The Rotech Subsea TRS1LD tool c/w HP Jets was selected by Saipem for this workscope due to advanced Technical capabilities and cutting ability in stiff soils.

The spread of equipment was mobilised on the Mubarak Multicat Vessel to complete the post lay trenching of various FPOC, flexible pipelines and umbilicals.

TRS1LD performance was as expected and Rotech Subsea delivered as promised in soils in excess of 200kPa undrained shear strength

Each Product was lowered to 1m Top of Pipe/Top of Cable below the adjacent seabed level. The post lay trenching operations were completed whilst progressing at a rate averaging 3m/minute.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY TRS1LD - SAIPEM
Trenching Q1 2019 / TRS1LD CFE SPREAD

TRS2- Sandwave Clearance

Q3, 2020 - Excavation Lines carried out by TRS2 & TRS2 Deployment

Rotech Subsea are contracted by Seaway 7 to provide the TRS2 CFE tool for Sandwave Clearance operations at OWF located in Taiwan. The scope of work is to be completed in 2 phases with phase 1 having being completed in the third quarter of 2020. Phase 2 is to commence in the early stages of 2021.

The TRS2 was selected by Seaway 7 due to its high volume output performance making it the ideal tool for sandwave clearance due to its ability to displace large amounts of subsea material. The Rotech Equipment was mobilised on the Topaz Installer and operated in water depths of between 5m-10m.

Phase 1 of the project was a success. The TRS2 was utilised for seabed lowering excavations. The TRS2 tool was used to carry out 25 grid Line excavations, lowering the seabed to allow vessel access to the worskite during spring tides. The sections to be levelled varied in height ranging between 0.4m - 1.8m. Rotech carried out excavations at speeds between 4m/min - 10m/min. Rotech look forward to returning to Yunlin Offshore Wind Farm to complete Phase 2 of the project in 2021.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY TRS2 - Seaway 7

TRS1LD & Jets - Orsted

TRS1LD & Jets - Cable Burial

2019 - TRSL1D & JETS SPREAD ON OSV RELUME

Rotech Subsea were contracted by Orsted to provide the TRS1LD Jet Trenching tool - equipped with HP jets - to carry out cable burial at OWF located in the Irish Sea. Rotech Subsea took control of all operations for this project from chartering the vessel to contracting all relevant parties required to carry out a successful excavation project. The TRS1LD was selected by Orsted due to its unparallelled technical and performance capabilities resulting in increased productivity and a reduction on the projects total costs.

The subsea spread of equipment was mobilised on the OSV Relume and deployed using the ships crane. Two separate cables (WOW03 & WOW04) - totalling approximately 3.5km in length - were to be trenched to Orsted specification of 2.0m TOC in the soft sand areas and to 1.0m TOC in the Stiff Clay areas. Water depth ranged from -2.0m to +14.0m LAT.

The project was a success,with the cables trenched to Orsted Specification at an average rate of 4m/min in the soft sand areas and 2m/min in the stiff clay.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY
Q3

TRS2 & RSG - Maersk Supply Services

TRS2 & RSG- Structure De-Burial & Recovery

Q3, 2020 - Rotech Equipment & the Structure to De-bury

Rotech Subsea were contracted by Maersk Supply Services to provide the TRS2 CFE tool for Jacket Template & Well-head De-burial in the Tyne Field. The Rotech RSG grab system was also used to assist in the recovery of a PLET Structure in the Southern North Sea.

The TRS2 was selected by Maersk Supply Services due to its high volume output performance making it the ideal tool for De-burial due to its ability to fluidise and displace large amounts of sediment. The Rotech Equipment was mobilised on the Maersk Inventor and operated in water depths of approximately 17m.

The project was a success. The TRS2 de-buried the Jacket Template and Wellhead with ease reaching up to 5.5m deburial depth. This was achieved in Dense Sand soils. The TRS2 was also additionally used for backfilling operations, minimising the effect on the seabed by filling the excavated area with the removed sediment allowing for NSBL to be achieved. The Rotech Grab operations were also a sucess with the grab being utilised to lift the cuts of the PLET into a subsea Basket.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY

RS1-2

RS1-2 - Remedial Cable Burial

Rotech Subsea were contracted to assist with remedial cable burial operations on x3 offshore wind farms offshore Germany.

Rotech provided the RS1-2 Hybrid Controlled Flow Excavator (CFE) equipment spread to carry out this scope.

Rotech were to carry out:

• Remedial Cable burial in various locations along multiple cables

• x1 cable to be buried to 1.5m Depth of Lowering

• All other cables to be buried to 3m Depth of Lowering – Reasonable endeavours.

Project Information:

Water Depth - 3m– 13m

Scope - Cable Burial

Soils - Silty Sands with intermittent hard layers

Currents - Up to 2.4 Kts max

General Sea State - 0.25 – 1m Hs

Rotech’s Scope of Work was to lower existing export cables on each worksite to client specific depths.

Wind farm 1 - 1.5mtrs DOL, Wind Farm 2 & 3 the spec was maximum 3m DOL or best endeavours should the material being excavated be too hard. Prior to the project it was known possible hard and cemented areas could be encountered along the route.

The RS1-2 was deployed from the vessel crane of single fall wire, the equipment was deployed over the starboard side of the vessel.

Vessel forward & aft deck winches were used for our orientation tuggers. These were routed through snatch blocks fixed to pad eyes on the extended outriggers.

The RS1-2 remained suspended above the seabed / cable and in line with the cable to complete all trenching operations. The vessel’s DP positioning system was used to move the CFE tool along the cable RPL routes/areas that required trenching works. The RS1 tool was the lead excavator. USBL transponders fitted to the tool provided accurate data on the location of the RS1-2 to ensure operations were completed in the correct locations.

Trench depth was monitored real time using a sonar imager mounted to the CFE tool to confirm the trench depth and when the cable had been buried to the correct specification for the remedial burial works. Once Rotech completed their scope, the client surveyed the area using separate survey equipment to confirm that the completed trenching ops met the required specifications.

Results

On Windfarm 1 - 1.5m Depth of Lowering was achieved with two passes. On Windfarms 2 & 3 the average DOL was 2 – 2.5mtrs. The mobility of the seabed was very active on these sites as confirmed by the client reps data with some areas gaining/losing up to 6mtrs over a season. This was completed in 2 passes and was passed off by client.

Rotech Crew and the vessel deck crew worked very well together with good communication which lead to safe & efficient tool launch and recovery operations, and overall project success.The RS1-2 hybrid tool worked very well and performed as expected and achieved the excavation specifications required by the client

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY
Operations

CASE STUDY TRS1LD

Rotech Subsea were contracted to assist with cable de-burial, post-lay and remedial trenching operations on an offshore wind farm offshore Taiwan. Rotech provided the TRS1LD Controlled Flow Excavator (CFE) equipment spread to carry out this scope.

Rotech were to carry out:

• De-burial of wet stored export cable sections

• Export cable remedial burial works

• Inter-array cable remedial burial works

• Inter-array cable backfill works

Project Information:

Water Depth - 30– 55m

Scope - cable de-burial, post-lay and remedial trenching, Backfill Operations.

Soils - Silty Sands, Clays, Very Dense Gravel with Cobbles.

Currents - Up to 2 Kts

General Sea State - 0.50 – 3m

The TRS1LD was deployed off the starboard side of the vessel using the ships crane. Outriggers and clump weights were setup forward and aft of the CFE tool and then connected to it with running lines to control the tool orientation.

The TRS1LD remained suspended above the seabed / cable to complete all trenching operations. The vessel’s DP positioning system was used to move the CFE tool along the cable routes/areas that required trenching works. USBL transponders fitted to the tool provided accurate data on the location of the TRS1LD to ensure operations were completed in the correct locations. Trench depth was monitored real time using a sonar imager mounted to the CFE tool to confirm when the cable exposed for deburial operations and when the cable had been buried to the correct specification for the remedial burial works. Once Rotech completed their scope, the client surveyed the area using separate survey equipment to confirm that the completed trenching ops met the required specifications.

De-burial and remedial excavation was completed using minimal power to avoid possible free-span. Trials were completed in 10m sections at various power levels 30-80%, and at various standoff distances from the cable/seabed, 1.3m standoff from cable and 2-4m offset, vessel speeds of 2-5m/min BOT depths ranged from 0.35-1.20m. Once the trials had been completed Rotech were able to complete the actual trenching scope with the optimal settings to achieve the clients desired trench specification.

The TRS1LD CFE tool has a maximum outlet pressure of 140kPa and a max jet flow of 2,600L/s. The soils in the area were extremely variable with Silty Sands, Clays, Very Dense Gravel with Cobbles all encountered throughout the project. Despite this, the Rotech CFE tool successfully completed the required operations on schedule with no issues.

Rotech Crew and the vessel deck crew worked very well together with good communication which lead to safe & efficient tool launch and recovery operations, and overall project success.

The TRS1LD performed as expected and achieved the excavation specifications required by the client.

+44 (0) 1224 698698 | subseainfo@rotechsubsea.co.uk | www.rotechsubsea.co.uk CASE STUDY TRS1LD
Rotech Subsea Rotech House Whitemyres Avenue Aberdeen AB16 6HQ T: +44 (0) 1224 698698 E: subseainfo@rotech.co.uk W: www.rotech.co.uk Backfilling capable equipment with more power, precision and suction RS1 | TRS1 | TRS1-LD | RS2 | TRS2 | TRS2-LD | RSG

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