Date post: | 14-Apr-2018 |
Category: |
Documents |
Upload: | architectintx |
View: | 215 times |
Download: | 0 times |
of 50
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
1/50
Norwegian Society of Lifting Technology
How can we assist in you r sub sea development
Presented by: Danny Mus
Date: 5 December 2012
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
2/50
Introduction, How can we assist in your subsea development
Introduction
Presentation contents How can we assist in your subsea development:
- Selection of subsea project from the past
- Typical project phases- Engineering phase
- Transport from yard to offshore site
- Field preparations: Survey and Positioning
- Lower structures through splashzone and set down on seabed
- Offshore Decision making
2
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
3/50
Subsea Lifting Experience (selection)
3
2005 | Norsk Hydro Ormen Lange
(Heaviest Subsea Template @ 850 msw)
2008 | DSME Tombua Landana
2009 | Hydro O&G Troll & Vega
2010 | BP Block 31
(Worlds Deepest Foundation Piles @ 2,030 msw)
2012 | Total Laggan & Tormore
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
4/50
Ormen LangeNorway
4
Record Lift
Heaviest Subsea Template @ 850 waterdepth
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
5/50
Client
DSME
Scope
Tower Base Section
Tower Base Template
Leveling Pile Template
Max. Weight
29,500 mT
Water Depth
370 m
Period
Q1 2008
Location
Block 14, Cabinda, Angola
Tombua LandanaAngola
5
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
6/50
LEVELLING PILES TEMPLATE
(LPT, 520mT)
-370 m.
waterline
GROUTED
CONNECTION
TOWER BOTTOM SECTION,
TBS, 29,500mT)
GROUTED
CONNECTION
TOWER BASE TEMPLATE
(TBT, 3010mT)
4 No. LEVELLING PILES (315mT each)12 No. FOUNDATION PILES (850mT each)
TOPSIDES ( Total
weight: 30,000T)
TOWER TOP SECTION,
TTS, 7000mT)
Tombua LandanaAngola
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
7/50
Troll & VegaNorway
7
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
8/50
Laggan TormoreUnited Kingdom
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
9/50
Block 31Angola
9
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
10/50
BP Block 31 PSVMExtend of Subsea Scope: Free Standing Riser installation
10
9 x Single Line Hybrid Riser (SLHR)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
11/50
Riser Base FoundationBallast Module & Driven Pile
11
12m
12m
~330mT @ 2,030m
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
12/50
12
Lower Riser Assembly
Weight = 23-36mT
Length = 41m
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
13/50
13
Upper Riser Assembly
Weight = 60-75mT
Length = 40m
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
14/50
14
Buoyancy Tank
Weight = 180-240mT
Length = 35-47m
Weight = 180-240 mT
Length = 35-47 m
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
15/50
15
Buoyancy Tank Stabbing into Upper Riser Assy
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
16/50
16
Install riser string into Riser base Foundation
Steel wire rigging
Riser string weight 500-600 mTRiser length ~1900 m
Polyprop stretcher in rigging
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
17/50
Rotolatch functionality (1)
17Ready to insert rotolatch(lowering)
rotate rotolatch(lowering)
lock rotolatch(lifting)
A Rotolatch is a locking
/ unlocking device
Load transfer from
steel rigging to
polyprop stretcher
Installation vessel heave is +/- 1m
Riser pre-tension by stretcher.
Stretcher is the absorber to
compensate heave of vessel.
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
18/50
Rotolatch functionality (2)
18
3 pairs of cams
Cam1
Cam2
Toolreleased
Toolengaged
2nd horizontal
left rotation
1st horizontal
left rotation
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
19/50
Lower complete riser string to locking position in base foundation
19
Freestanding Riser Systems: Stabbing Riser
Transferring weight from polyprop stretcher to buoyancy tank
Riser string weight is transferred from steel wire arrangement to
polyprop stretcher arrangement (damping motions)
Heave of vessel is absorbed by polyprop stretcher
Free stabbing Rotolatch connector at seabed
Inserting and locking of Rotolatch in foundation
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
20/50
Free Stabbing of Riser
20
Position and lowerLower and Rotate
Lift and engage
Final position
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
21/50
Typical Project Phases
21
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
22/50
Project Phases and Issues encountered
22
Engineering preparation stage
Transport from fabrication yard to offshore location
Field preparations for survey and positioning
Lift structure from barge or SSCV deck
Lower structure through the waterline (splashzone)
Lower structure through the watercolumn
Position and land the structure on the mudline/seabed/template or
foundation already installed
Level structure if necessary
Completion work
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
23/50
Engineering Preparation Phase
23
Typical Subsea Transport and Installation Project, engineering topics:
Barge transport engineering (motion response analysis, grillage and seafastening
design, bollard pull requirement)
Transfer transport unit to SSCV option
Single vs dual crane installation
Anti twist system, anti rotation system
Rigging release systems
Installation engineering (rigging design, dynamic analysis, suction foundation analysis
etc)
ROV detailed scope of work
Survey and positioning detailed scope of work
Handling equipment specification
Installation manual
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
24/50
Transport from yard to Offshore Site
24
Typical Subsea Transport and Installation Project:
Transport from fabrication yard to offshore location
On barge
On SSCV deck
Combination of both (inshore transfer)
Laggan Tormore structures on 400 barge
Vega structures on barge
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
25/50
Transport from yard to Offshore Site
25
Laggan Tormore structures on Thialf
Deck
Tombua Landana TBT on barge H627
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
26/50
Transport from yard to Offshore Site
26
Barge vs Thialf deck transport:
Size and weight structure
Space on deck SSCV
Liftable from deck
Quay location
Access barge vs access SSCV
Workability (lift off from barge vs lift off from Thialf deck)
Offshore lift from barge weather sensitive
Offshore lift from SSCV deck less weather sensitive
Transfer lift to SSCV deck in sheltered waters
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
27/50
Lift Structure from Barge or SSCV deck
27
Lifting the structures from SSCV deck or barge
Pros lift from SSCV deck Pros lift from barge deck
Lift off no critical weather operation Heavier and larger structures can be installed
Preparations to structures direct from SSCV
deck
No height restriction of structure
No barge mooring operations offshore
No people transfer to offshore barge
Rigging attachment less weather restrictive
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
28/50
Field Preparations, Survey and Positioning
28
Installation tolerances drive the field preparations. In order to position the
structure within tolerances (position and heading) a few methods/options can be
distinguished:
1. Positioning via DP and subsea transponder array
2. Positioning via gravity (pre-installed) anchors
3. Subsea infrastructure already present, dock structure over other structure
Each of above mentioned methods have their own accuracy. As back up method
the installation of subsea marker buoys are often used.
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
29/50
Positioning by Transponders
29
1. Positioning via DP and subsea transponder array
Transponder array to be pre installed and surveyed
Transponders on subsea structure for communication with array
ROV interface
Example: Laggan Tormore
Installation Tolerances for positioning SWPS:
Final as built data, position from target:
Structure Position Heading
SWPS +/- 0.50m +/- 2.00
Structure Position Heading
SWPS 0.14m 0.30
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
30/50
30
Laggan Tormore Example
Transponder array
Template Target
Typical Survey plot:
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
31/50
Positioning by Gravity Anchor
31
2. Positioning via gravity (pre-installed) anchors
Gravity anchors to be pre installed and surveyed
Sling length determined and custom made
Subsea attachment by ROV
Example: Ormen Lange
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
32/50
Positioning on Structure
33
3. Subsea Structure already present; dock structure over other structure
Docking guides and receptors required for positioning and guiding
Docking loads during installation (steel on steel, docking study)
Subsea connection between foundation and structure
Example: Tombua Landana Compliant Tower, TBT Installation
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
33/50
Positioning on Structure (2)
34
TBT; L*B*H ~ 34*34*22,
W ~ 3010mT
Foundation Piles; L ~ 190m, diam 108
W ~ 850mT each
Barge H-627; L*B*H ~ 177*49*11m
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
34/50
Installation sequence, TBT landen on LPT
(Levelling Pile Template)
Primary, secondary and tertiary docking pin
engaged
36
Tombua Landana Example
Mudline -370 m.
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
35/50
Lower Structures Through the Waterline
(Splashzone)
37
Lifting structures Through the Splash Zone
Dynamic Loads! (DNV-RP-H103) vs design forces
Multiple installation stadia
Structure mass and drag area vs water particle acceleration and velocity,
Hoist wire dynamics, hatch loads, equipment loads etc
Wave force on structure, transferred to rigging and hoists
2 Stages (multiple stages can be defined): Roof just above water and roof just
below waterline:
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
36/50
Orbital wave motion
Source picture: http://fcit.usf.edu/florida/teacher/science/mod2/beach.profiles.html
38
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
37/50
Wave particle motion for deep water described as circles, decreasing with waterdepth:
39
Wave orbital motion
Wave period
Waterdepth
Short waves highest effect on slamming
loads but depth effect is large
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
38/50
40
Wave particle motion for deep water described as circles, decreasing with water depth:
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
39/50
Influence crane tip motions (velocity and acceleration) is very minimal wrt water
particle velocity and acceleration. For a wave period of 6 s, the heave velocity
and acceleration is ~ 2% of the water particle velocity and acceleration!
In other words, the installation vessel hardly moves and slamming loads are
only wave induced, not vessel (motion) induced
41
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
40/50
Resulting maximum wave
height based on maximum
allowable dynamics (rigging
design driven, template
design more critical):
42
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
41/50
Result is completely
opposite of normal
installation limits.
Normal limits driven by
vessel induced motions
Characterized by:
Hs
43Tp
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
42/50
Effect: short crested waves defined the installation limit
for wave periods around 6 seconds
Low(er) workability!
SSCV is a very large vessel, what is the influence of
the SSCV on the local wave field?
SSCV Shielding study
Shielding effect of SSCV: SSCV, installing a template
on the lee side of the vessel, sheltered from (short
crested) waves.
44
Wave
propagation
SSCV
Template
Lower Structures Through the Waterline
(Splashzone)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
43/50
Wave Reflection effects
SSCV Radiation effects
Wave Diffraction effects +
Installation Vessel Shielding Study
Input characteristics
JOHNSWAP Wave Spectrum
6s < Tp < 20s
0 degr < wave heading < 355 degr
Results
Tp = 6s
Wave heading 225 degr (bow quartering)
50% reduction on wave height
45
Lower Structures Through the Waterline
(Splashzone)
Installation Vessel
Wave
propagation
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
44/50
Set-down structures on seabed
Dynamic Loads vs design forces
Maximum set down velocity on seabed (~ 0.5m/s)
Hoist wire dynamics (max DAF)
Vessel induced motions characterize dynamics,
transferred to rigging and hoists
Mass Spring System, natural behavior defined by:
* mass and added mass template
* waterdepth / reeving length
* Environmental Conditions / crane tip motions(wave induced vessel motions)
* hoist wire stiffness (spring term)
* template drag (damping term)
46
Lower Structures
(Set-down on seabed)
Mudline
Crane tip
Motions
Hoist wires
Vessel
Motions
Template
Motions
Waves
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
45/50
Create model (frequency domain) Thialf, hoist wires, template:
Per wave heading, obtain template heave velocity RAO and
Hoist wire dynamic force RAO.
47
Lower Structures
(Set-down on seabed)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
46/50
Create model (frequency domain) Thialf, hoist wires, template:
Per wave heading, obtain template heave velocity RAO and
Hoist wire dynamic force RAO.
For maximum allowable template velocity 0.5m/s and hoist wire dynamics,
define allowable wave height per peak period and wave heading:
48
Lower Structures
(Set-down on seabed)
Hsallowable
Hsallowable
V < 0.5m/s DAF < allowable
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
47/50
At start of project, wave rider buoy is deployed and directional full spectral
wave and weather predictions obtained.
Decision making tool: compare measurements with predictions, with
RAOs decide on installation window where DAF and set down velocity
will be within limits.
49
Lower Structures
(Offshore Decision making)
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
48/50
50
Lower Structures
(Offshore Decision making)
Check predicted vs measured
waves (Hs)
Check near bottom vertical heave
velocity template within limits
Check DAF within limits
Date, time
Limiting criterion dynamic force
Limiting criterion heave velocity
Hs
Vheave
Fdyn
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
49/50
51
Position template on seabed
When a suitable window is there:
Attach rigging
Cut seafastening
Lift from deck, lower through the
water column and set down on
seabed
Release rigging
Perform hatch operations
Apply suction (if needed)
Completions
7/30/2019 11 - HMC 5Dec Norwegian Society of Lifting Technology[1]
50/50
Questions?
Email: [email protected]
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]