Mob. Personnel &
Equipments
Onshore Site Preparation
- Fabrication Pipe Ramp Launcher
- Fabrication new U-Spool (welding)
- Fabrication west/east gooseneck (optional to
be fabricated onshore/offshore)
- Fab. end flange for new spool & gooseneck
(optional)
- Hydrotest on fabricated new U-Spool (option)
Launching new U-Spool
- Install floaters & wire on new U-Spool
- Install stability guide on new U-Spool
- Side-boom/Backhoe required
Offshore Fabrication
- Welding West/East Gooseneck to new
U-Spool (optional using Flange)
Transportation to Offshore
- West/East Gooseneck (optional to be
fabricated on derrick barge)
- Material for Tie-In Spool (west/east)
- A-Frame (if any offshore lifting required
for tie-in)
Offshore Site Preparation
- New Trench preparation
(backhoe dredger, swamp backhoe, etc)
- Installation Cofferdam (west/east point)
– using sheet pile / sand bags, etc (optional)
- Develops access channel for new U-Spool (TBA
during Pre-Lay Survey)
Cutting Process
- West/East Point for future tie-in on the
existing mainline/OLD U-Spool
Remove OLD U-Spool
TIE-IN (west point) – Lift & Lower
- Lifting on WEST line & new U-Spool
end (west side) – check integrity
- 1st Metrology and Fit-up
- Welding west point (tie-in spool will be
required)
- Lowering (mainline & new U-Spool)
west side
- Connecting Flange (optional tie-in)
TIE-IN (east point) – Lift & Lower
- Lifting on EAST line & new U-Spool
(east side) – check integrity
- 2nd
Metrology and Fit-up
- Welding east point (tie-in spool will be
required)
- Lowering (mainline & new U-Spool)
east side
- Connecting Flange (optional tie-in)
Installation of Marking Piles for
new U-Spool
Installation of Protection Covers
- sand bags
- concrete mattress (option)
- rock dump (option)
Demob of
personnel/equipment
(except for as built survey)
As Built Survey
Pre-Lay Survey
Assumption:
� Shutdown Operation
� Pipeline De-Gassing to be done
� Low level construction HSE
� Inshore Replacement Location
� 4.5m minimum offset / parallel
distance (depend on trench width
and soil shear strength)
Towing to offshore
TIE-IN (west point) – Cofferdam
- Lowering new U-Spool in new Trench
- 1st Metrology and Fit-up new U-Spool
end to west/east point
- Welding west point (tie-in spool will be
required) inside Cofferdam
- Connecting Flange (optional tie-in)
TIE-IN (east point) – Cofferdam
- 2nd
Metrology and Fit-up new U-Spool
end to east point only
- Welding east point (tie-in spool will be
required) inside Cofferdam
- Connecting Flange (optional tie-in)
Alternative
using WELDING
Alternative
using WELDING
Floaters installation on
OLD U-Spool
Coordinated Pipeline De-
pressurized/shutdown
Pipeline De-Gassing / N2
Purging
Using WELDING/Flange
Using WELDING/Flange
Required special equipment
for underwater BT installation
To be coordinated with all
construction preparation
Drag / Lift the OLD U-Spool
using AHT/Derrick Barge
(TBA)
In case tie-in using Flange is applied, lifting
and lowering works to be minimized.
TIE-IN (west point)
- Deploy griplock connector and stabbed
onto the west line
- 1st Metrology at west point
- Fabrication tie-in spool complete with
Flangemate adjuster on Board
- Fit-up & Bolted
TIE-IN (east point)
- Deploy griplock connector and stabbed
onto the east line
- 2nd
Metrology at east point
- Fabrication tie-in spool complete with
Flangemate adjuster on Board
- Fit-up & Bolted
Using MECHANICAL CONNECTOR
Alternative process if Tie-In
using Mechanical Protector is
applied.
COLD WORK METHOD
Pre-Commissioning
Top Related