12-6-5 AGR Seabed Intervention Track Record seabed Intervention Ltd Union Plaza 1 Union Wynd...
Transcript of 12-6-5 AGR Seabed Intervention Track Record seabed Intervention Ltd Union Plaza 1 Union Wynd...
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
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Project name Tangguh Pipeline Trenching & Route Preparation Project
Equipment used SeaVator; V Jets; Dual SeaBat 9002 Sonar
Operator BP
Client Saipem
Location Indonesia
Pipeline diameter 24”
Trench length Multiple short sections of pipeline route preparation – pre-sweeping through sand waves and sediment, dispersing debris and post pipe-lay free-span correction.
Water depth 70m
Soil strength Sand, sediments and soft clays.
Vessel names DSND Surveyor
Comments
This project was undertaken in a very remote location without any regular shore based support. The site conditions were very challenging as the area possessed extremely uneven and rough seabed topography with highly variable soil conditions, including unconsolidated sands and silts, soft mud and stiff clays. Notwithstanding strong seabed currents of up to 1.5m/sec and a 4 metre tidal range the operation was completed successfully.
SeaVator Equipment Spread
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Pinghu Oil Pipeline Burial Project (Live Pipeline)
Equipment used SeaVator, V Jet System 1200 HP Version, Dual SeaBat 9002 sonar
Operator China National Offshore Oil Corporation (CNOOC)
Client China National Electronic Equipment Company (CNEEC)/ Merloni TermoSanitari (MTS Group)
Project period 2002
Location Dai Shan Province, South China Sea
Pipeline diameter 16”
Trench Details 3 km, up to 2.9 metres to TOP
Water depth 2 – 27 metres
Soil strength Sand and Clay From 3 – 50 kPa
Vessel names Yang Gang Bo 16
Comments
This project took place in very severe and turbid coastal sea conditions interrupted by typhoons with high prevailing currents of up to 7.2 knots across an estuary. Trenching operations were conducted from a shallow drafted moored barge operated by CNEEC. The majority of the work was conducted in currents speeds of approximately 3.5 knots with the pipeline in a full production at 2000 psi operating pressure.
SeaVator & V Jet Assembly (Parallel Orientation)
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name PTT 3rd Pipeline Trenching Project
Equipment used SeaVator; V Jets; Dual SeaBat 9002 Sonar
Operator PTT
Client Hyundai
Project period March to November 2006
Location Thailand
Pipeline diameter 48”
Trench length Several discrete sections of pipeline trenching along a total pipeline length of 90 km
Water depth 40m
Soil strength Clay soils with strengths from 5 kPa to 300 kPa.
Vessel names MV Sartu Santabong
Comments
Generally the upper 1.5m of seabed consisted of sand and gravely silts in some areas and 1 to 50 kPa clays in other areas. For such soils the SeaVator with 1,200hp V Jets was used. In order to carry out the job efficiently a SeaVator with 4,500hp V Jets was also used areas possessing higher soil strengths to achieve the required excavation depth.
SeaVator & Multi – Jet Assembly
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name LGTS Green Stream Project
Equipment used SeaVator; V Jets (both 600 and 1,200 hp versions); Dual SeaBat 9002 sonar
Operator Agip
Client Saipem / Sonsub
Project period September 2003 to July 2004
Location Libya and Sicily
Pipeline diameter 36”
Trench length Total of 30 km in section lengths of 3km to 7km trench depth various; 14km to 1.5m; 6km to 3.5m; other areas to 4.0 and 5.0m trench depths
Water depth 4.5 - 55 metres
Soil strength Loose sand; dense sand; weak sand stone & clays up to 37 kPa
Vessel names MV Polar Prince; MV Sentinel; MV Skandi Inspector
Comments
This project required a wide range of different trench depths in a variety of soil conditions. In addition the SeaVator & V-Jet systems were used to excavate areas up to 0.5 km in length and 5 metres deep to allow inspection and repairs to the pipeline and to bury boulders and debris under the pipeline. The SeaVator (using tilt beam) was also used to backfill sections of trench.
SeaVator & V – Jet Assembly (Perpendicular Orientation)
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Giovanna field IRM
Equipment used SeaVator; V Jets; Dual SeaBat 9002 Sonar
Operator ENI
Client Saipem/Sonsub
Project period February/March 2008
Location Adriatic Sea
Excavation Depth Down to 3m below seabed
Water depth 42m – 80m
Soil Strengths Loose sands, natural backfill, some stiff clays
Vessel name Texas Horizon
Comments SeaVator was used to debury a variety of pipelines for inspection/repair work. V-jets were deployed to dig some areas of stiff clays to allow access to the underside of trenched pipelines.
SeaVator & V Jet Assembly (Perpendicular Orientation)
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Ormen Lange Southern Field Extension Route Preparation Project
Equipment used ClayCutter X; AquaDrive SeaVator
Client StatoilHydro
Project period July 2008
Location Offshore Norway
Trench Width 5m
Trench Length 1500m
Water Depth 870m
Soil Strength Clay from 15 kPa to 440 kPa Shear Strength
Vessel name Island Valiant
Comments
ClayCutter X was mobilised in conjunction with AGR’s new build trenching pumps to prepare the seabed around the Ormen Lange field. In total 3,400 m3 of clay was excavated at rates of up to 500 m3/hr. The excavation was split between 10 separate sites of varying complexity and soil strength. Overall the project was completed in 17 days, compared with an initial prognosis of 32 days for 1975 m3. All of the equipment performed flawlessly and the project was completed without any harm to personnel or the environment.
Pre-Excavation 3D DTM Post-Excavation 3D DTM
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Black Tip Pre-Lay & Post-Lay Intervention Project
Equipment used SeaVator; V Jets; Dual SeaBat 9002 Sonar
Client Saipem
Project period September 2008 to February 2009
Location Darwin, Northern Australia
Pipeline Diameter 18” & 12” Pipelines
Water depth 70m
Vessel name Miclyn Endurance
Comments
The SeaVator scope of work included pre-pipelay sweeping of sand waves and post-pipelay freespan correction. The upper 1.5m of seabed consisted of sand and gravelly silts in some areas and 1 to 50 kPa clays in other areas. For such soils the SeaVator with 1,200hp V Jets was used.
Pre-Excavation 3D DTM* Post-Excavation 3D DTM*
*Images produced by Fugro for AGR
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Trans Gas Indonesia Pipeline Repair Project
Equipment used SeaVator 60 bar Monojet ; Dual SeaBat 9002 Sonar
Operator TGI
Client Global Industries
Project period February/March 2009
Location Offshore Sumatra, Indonesia
Excavation depth 2m below seabed
Trench length Variable
Water depth 50m
Soil strength Loose sands, clays up to 100 kPa
Vessel name Sanko Angel
Comments
SeaVator was used to excavate boxes around a pipeline to enable access for clamps prior to a hot tap. Soils were expected to range up to 100 kPa so a high pressure pump and extended central jet were employed to cut these stiff clays. Once on location the soils ranged up to 395 kPa, beyond the capability of the equipment, but soils up to 100 kPa were excavated successfully – well beyond the usual operating limits for mass flow equipment.
SeaVator & Mono – Jet Assembly
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Ekofisk Cessation Project
Equipment used AGR Disc Pump Dredge System
Operator ConocoPhillips
Client Heerema Marine Contractors
Project period June-August 2009
Location Norwegian North Sea
Excavation depth 4m below seabed
Water depth 50m
Soil strength Loose sands, grout bags, general platform debris
Vessel name Thialf
Comments
Excavation of loose sands and general debris from around platform risers and piles prior to cutting. The work was performed using AGR’s unique CTS high-flow area pumps as the distance required for discharge of the spoil was greater than could be achieved using traditional ejector pumps. The equipment coped well with a very challenging range of platform debris which included cable trays, gloves, grout bags amongst other detritus. The work was performed under the AGR frame agreement with HMC.
CTS pump skid and LARS in position on the Thialf
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Baltic Beta Spud Can Excavation
Equipment used AGR Disc Pump Dredge System
Operator PetroBaltic
Client PetroBaltic
Project period June-August 2010; May 2011-March 2012
Location Baltic Sea
Excavation depth 9m below seabed
Water depth 80m
Soil strength Clays to 180 kPa, small boulders, grout bags, general platform debris
Vessel name Granit
Comments
Excavation of clays and debris from around jackup legs & spud cans to allow access for dive inspection. Combination of AGR Disc pump and high pressure jetting system gave good progress even in soils much stiffer than prognosed. Work continued on the other legs in 2011.
ROV arm and dredge pump suction head in action
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name North Scarp Excavation
Equipment used ClayCutter X with Coiled Tubing and Fall Pipe ROV
Operator Chevron
Client Van Oord
Project period July 2010-May 2011
Location NW Shelf Australia
Excavation depth 9m below seabed
Water depth 650m
Soil strength Overconsolidated carbonate silts to 180 kPa
Vessel name Tertnes
Comments
An entirely new deployment system was devised for this ClayCutter X job. The workscope involved excavating around 4,000 m3 of soil from a subsea scarp feature to enable the export pipeline to be laid in the most direct route. Due to the high variation between the top & bottom of the excavation area (80m) a system utilising composite coiled tubing for water transport and a heavily modified fall pipe ROV was designed, built & tested. The system gave excellent results in terms of ease of deployment, low pressure losses through the conduit and accuracy of positioning of the ClayCutter X.
AGR seabed Intervention Ltd
Union Plaza
1 Union Wynd
Aberdeen
AB10 1SL, UK
Tel: +44 1224 629280
www.agr.com
SEABED INTERVENTION
Project name Ormen Lange Mid North Extension
Equipment used ClayCutter X deployed on drillpipe
Operator Shell
Client Shell
Project period February 2011-October 2011
Location Offshore Norway
Excavation depth Up to 9m below seabed
Water depth 900-930m
Soil strength Clays from 15 to 440 kPa
Vessel name Island Valiant
Comments
A return to the Ormen Lange field saw a substantially greater workscope compared to the 2008 campaign. In all 42 separate sites were excavated, giving a total volume of excavated soil of 25,000m3. The largest single site required 4,698m3 of soils to be removed and the deepest seabed penetration was 9m. The project was completed with minimal mechanical downtime and without serious HSE incidents.