F P S O

measlyincompetentUrban and Civil

Nov 29, 2013 (3 years and 7 months ago)

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FPSO’s : NO TWO ALIKE


F P S O

P
AST

I
SSUES

AND

T
YPICAL

C
LAIMS

Houston Marine Insurance Seminar
-

September 2012


Ted Miller, Charles Taylor Adjusting


Houston



EJM 21 Aug 1022


Review and Discussion Points


1. The early days (80’s): FPSO’s local conversions from existing tanker hulls

2. The condition of some early FPSO Tanker hulls and hull prospects

3. US GOM Fleet

4. Manufacturing issues

5. Mooring line issues

6. Umbilical Issues

7. Flexible Riser issues

8
. Hull Issues

9
. Topside process system issues

10. Loss of station keeping
-

major event

11. Repair
and remediation costs

12. Wrap up








Zafiro

Producer
Early
FPSO Conversion
in Galveston and Portugal

Major ballast tank, bottom and steelwork repairs.

Operated Offshore Equatorial Guinea 1996

Jamestown


FPSO Early Production System
-

Kewit South Texas

Minimal hull repairs, built 1957 41,500 dwt.


heavy scantlings.

Early Production Vessel

Condition of tanker hulls for conversion

Condition of Tanker as FPSO conversion candidate is
Critical

Extract :Australian Transport Safety Bureau Findings

The

Kirki

carried

all

necessary

statutory

safety

certificates
.

Safety

surveys

had

been

carried

out

within

the

schedules

required

by

the

relevant

international

safety

conventions
.

The

scheduling

of

the

Kirki's

special

five
-
year

survey

at

22

years,

rather

than

at

20

years,

was

consistent

with

the

ship's

survey

program

and

within

the

rules

covering

the

frequency

of

special

surveys
.

The

defects

in

the

life
-
saving

appliances,

fire
-
fighting

equipment,

cargo

equipment

and

the

condition

of

engine

room

equipment

were

so

numerous

and

of

such

a

nature

that

the

Inspector

cannot

accept

that

they

all

developed

over

a

short

period

of

time
.

The

patching

with

canvas

and

the

camouflaging

of

No
7

tank

lids

was

a

deliberate

attempt

to

mislead

any

person

undertaking

a

load

line

survey
.

It

is

not

possible

to

determine

when

the

lids

were

patched,

and

it

might

not

have

been

done

with

the

knowledge

of

the

owners

or

those

on

board

the

Kirki

on

21

July

1991
.

Significant

defects

should

have

been

observed

during

surveys

b
y

Classification

Society
;

inspections

by

the

Oil

Major

Vetting

and

the

Vessel

managers

and

operators
;

and

inspections

by

the

Port

State

Maritime

Safety

Authority
.

The

Classification

Society

was

responsible

for

the

issue

of

statutory

certificates

on

behalf

of

the

Hellenic

Republic

of

Greece
.

The

procedures

adopted

by

the

Society

during

structural

surveys

failed

to

identify

the

areas

of

localised

corrosion
.

The

condition

of

ballast

tanks

13

and

14

together

with

the

number

and

nature

of

deficiencies

in

safety

equipment,

indicates

that

a

number

of

surveys

over

a

period

of

time,

including

surveys

that

were

conducted

under

international

safety

conventions,

were

not

performed

effectively
.


U S GULF OF MEXICO FLEET



U. S. GULF OF MEXICO


FPSO FLEET



Single FPSO Unit


Multiple moored FPU’s

US Gulf of Mexico HELIX PRODUCER 1
Converted Ferry


Croatia in 2008


Ship Shaped Floating Production Unit
FPU

Topsides installed Corpus Christi Texas 2009


Disconnectable Transfer System
-

DTS Operating Water depth 2,100ft


Deployed at G
reen Canyon 237 Phoenix Field (Ex Typhoon)

US Gulf of Mexico
BW Pioneer
Converted in China and Singapore in 2010



Originally Double Hull 1992 Tanker

First
FPSO


Disconnectable Operating
Water depth
8,200


Ultra Deepwater)



Deployed
at
Walker Ridge 249 Cascade and Chinook Fields








World Record Polyester Mooring
Depth

12

(11+1 spare) lengths x 2.5km long x 800 tonne MBL Polyester Tethers.

This is

a
new world record for continuous lengths of polyester mooring tether.





MANUFACTURING ISSUES



Modern analytical tools


get design /
specifications right


Reliant on manufacturers to produce to
spec. and codes


Operators however rely on QA
-
QC of
manufacturers and suppliers


Onsite inspections by operator essential


Reliance on 3
rd

party Inspectors


Small issues


catastrophic events



MOORING LINE ISSUES

Many different designs, layouts and materials

More incidents likely as FPSO systems age



Chain lines


Steel


Wire Rope lines


Steel


Synthetic fiber rope lines


Polyester


Shackles, Links and Jewelry
-

Steel



Relatively few manufacturers of large
diameter mooring components worldwide
.





Steel Mooring chains and equipment

A chain system is only as good as its weakest link

Catastrophic Failures in Mooring Systems Possibly

Put Floating Structures at Risk


In

early

2011
,

a

single

point

mooring

system

for

a

deepwater

Gulf

of

Mexico

(GOM)

project

failed

at

the

chain
.

Based

on

the

investigation

of

this

event

and

a

review

of

historical

events,

BOEMRE

is

revising

and

re
-
issuing

Safety

Alert

#
259
.

The

investigation

determined

that

a

6

¾
-
inch

diameter,

862
-
pound

chain

link

in

the

tether

chain

had

fractured

and

separated

near

its

butt

weld
.

Analysis

of

the

fracture

indicated

that

the

chain

link

had

a

weld

repair

and

the

fracture

initiated

in

the

middle

of

the

weld
.

Three

links

of

the

24
-
link

tether

chain

were

found

to

have

weld

repairs
.

Mooring Line Failure
-

2

Brittle fracture caused by
reversible temper
embrittlement (RTE) during
shackle heat treatment

Tear in steel wire line sheathing

g

FPSO Sheathed steel wire rope Mooring Line

Installation vessel
deployment line
damaged HDPE
coating on mooring
line, exposing wire


Can the cathodic protection reserve
cope over life cycle
-

No Cost


Can local repair be carried out


Minimal cost


Must the rope to be replaced.




Very expensive repair
.


Polyester Mooring Ropes

9 “Diameter Polyester outer sheath

Main Strands 8 triple 1
-
1/2 “ 4RH Lay and 4LH Lay

Main Strands 8 triple 1
-
1/2 “ 4RH Lay and 4LH Lay

Strand Ends being Prepared for Splicing


Strand Ends being Prepared for Splicing


Strand ends being prepared for splicing Eye to Link

Other mooring line Issues


Chain to Rope Transition Link misassembly which caused damage to
one

link and line:


Are the
other 9 links and lines
“damaged” if their links wrongly assembled?



Deepwater and Ultra DW
-

Lead Time for replacement components



Very limited manufactures, propriety information, installation spread availability,
unique designs, new engineering for repair procedures, timing and logistics




Umbilical Issues

Damage due to design detail and unexpected delay

Flexible Risers and flowlines
.



Flexible Manufacture

Carcass formation > Sheath extrusion (twice) > Pressure armouring >


Flexible in carousel < Insulating & taping < Axial armouring

Flexible Risers and flowlines.




.

Pressure Armor Pitch
-


Handling or operational errors can cause unlock and Failure

Leak


Leak Detection


Line or end fitting

Pressure Armour Pitch
-


Errors cause unlock & failure

39

RISER CORROSSION


Hull Issues


External Hull Sacrificial
-

Anode Loss
in Transit


Paint peeling on side shell


Damage or
Warranty


Ship Hull Bilge keel damage Cause
under investigation


Sterntube seals leaking


Damage or
maintenance issue



Topside Industrial Process Systems


Gas Turbine Gas generator blade
-

Accelerated Corrosion


Flare Tower insulation loss


manufacturing defect


Blade keeper parting FPSO off India


OEM Facility in
USA


Multiple Gas Turbines to OEM in Houston


Compressor module FPSO North Sea
-

although built and
installed as module repairs required entire compression
unit

to be removed


Massive increase in repair cost

Gas Turbine


Gas generator blade damage


Hot corrosion caused by combination of sodium & sulphur


Sulphur from high sulphur diesel


Sodium from seawater


air intakes ingest spray.


Question on other units :


Aggressive deposits form before blade material corrodes


Is contamination damage

&/or is dismantling, cleaning, rebuilding &
retesting covered ??

Fire on gas compression module

Entire unit has to be removed for repairs


Loss of Station keeping


FPSO with central turret / drag chain system


FPSO thruster operation is required to maintain heading


Multiple risers umbilicals / flowlines


Failure of heading / station keeping & mooring systems


Brief electrical power failure


Excursion beyond dynamic riser & umbilical operating limits

First FPSO Full Field Development


Gryphon’ North Sea 1993

Loss of Station keeping
-

Major Event


Extensive damage to risers, subsea facilities and turret


Extended repair period due to specialist equipment


FPSO has to be removed to drydock for repairs


Field restoration expensive


Very large LOPI Claim
-

well in excess of the Physical Damage



Costs
-

Construction Examples



Flexible Riser Failure 9,000,000
-

25,000,000


Mooring Line Failures 17,000,000
-

52,000,000


Turret Weld Failures




12,000,000


Bilge Keel Cracks





20,000,000


Thruster Seal Failure




12,000,000


Fire Main Leaks





6,000,000


Turbine Corrosion




5,000,000


Anode Failures





10,000,000


Costs
-

Operating Examples



Loss of Submerged Mooring Buoy 2,000,000


LOPI






100,000,000


Loss of Station Keeping



300,000,000


LOPI






500,000,000


Fire in Gas Compression Module


20,000,000


LOPI






150,000,000


Failure of Quick Disconnect Turret 25,000,000


LOPI






250,000,000

WRAP UP