Mooring Integrity & FUMA Why is it needed? How is it …€¦ · Mooring Integrity • Moorings are Safety Critical Components, inherently protecting the vulnerable subsea architecture

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Mooring Integrity & FUMA

Why is it needed?

How is it achieved?

Sept 2014

Mooring Integrity

Moorings are Safety Critical Components, inherently protecting the vulnerable subsea architecture (risers, umbilicals, flowlines etc), together with hydrocarbon production and adjacent assets

Mooring Failure is regarded as a Class 1 Hazard, the highest rating by the UK Health & Safety Executive

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Mooring Systems Typical Field Infrastructure

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Mooring Systems Typical Field Infrastructure

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Mooring Systems FPSO Expanding market

Source EMA 6/14 & Infield 6/13

264 FPS at 6/14, 60%

are FPSOs

Compound annual growth of 18% to 2017, increasing in size, value & complexity

95% increase in 10 years to 2017

Drivers - monetise gas at remote locations & focus on deep water

Dominated by Africa, Latin America & Australasia

Mooring Systems FPSO Expanding market

Prelude FLNG:

488m by 74m hull

600,000 tonne weight

Kizomba A FPSO is 285m by 63m

90m high turret

250m water depth

Cat 5 cyclones (>156 mph)

24 legs, 15.1 & 11.6 miles of chain & wire

Source: The Engineer 09 & ship technology.com

7-8 additional Asia-Pacific FLNG projects proposed

Source: Upstream 5/11

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Mooring Systems FPSO Expanding market

Prelude LNG Terminal Kanowit LNG Terminal Abadi Bonaparte Scarborough

Operator Shell Exmar Petronas Excelerate Inpex Masela GDF

Suez/Santos ExxonMobil

Status (as of Feb 14)

Under construction

Under construction

Under construction

FEED completed

FEED in progress

FEED in progress

pre-FEED completed

Location 200 km W of

Australia Caribbean coast

of Colombia 180 km N of

Bintulu, Malaysia Lavaca Bay, Texas

coast 350 km E of East

Timor 170 km N of

Australia 220 km NW of

Western Australia

Water Depth 250 m Unknown 80 m Unknown 350-1000 m 85-100 m 900-970 m

L x B 488 x 75 m 144 x 32 m 365 x 60 m 338 x 62 m ~500 x 80 m ~400 x 70 m 495 x 75 m

Environment (Typhoon)

Hs: 11.0 m - Hs: 13.6 m - Hs: 5.5 m Hs: 11.0 m Hs: 13.0 m

Expected First Production

2017 2015 2015 2018 2019 2019 2020-21

Mooring Systems Hardware

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Mooring make up:

Chain, mostly studless, up to 6.5 inch

Wire unsheathed or sheathed spiral or 6 strand

Polyester rope unsheathed or sheathed

Connecting shackles

Buoyancy support modules (buoys)

Anchors or piles

Mooring Systems Hardware

Spread mooring Single point mooring - external turret Source: API RP 2SK

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Mooring Systems Vulnerability inherent design

Limited redundancy in mooring system, chain as strong as its weakest link

Difficult to inspect & maintain, degradation & retirement issues

Rapid incident escalation (eg cascading failure) in hostile environments

Consequences lead to major loss including damage to subsea & seabed architecture and adjacent infrastructure

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Mooring Systems Vulnerability - Codes

Issues:

Various codes on mooring design, less on installation, operation, inspection & retirement

Differences in technical standards between Societies

Regional differences within Societies how good is the surveyor?

Standards only periodically updated (behind the curve, e.g. new failure modes)

Societies recognise that existing rules do not ensure FPSO mooring integrity

Source: Oil & Gas UK Report OP023 (2008)

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Mooring Systems Vulnerability - Codes

Class Rules evolving from seafaring background

Existing developments: Class - Ageing, many legacy systems in place (eg SPMs & offloading tankers). Equipment replacement considered as repairs, obsolete Class codes utilized

Tanker conversions to FPSOs, change in duty

New developments Speedier, smaller operators, remote & unpredictable environments, deeper water, more subsea infrastructure, increased asset values

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Main Factors Influencing Long-Term Mooring Integrity including inspection and maintenance, mooring jewellery

Source: HSE 2006 study

Also inspection and maintenance, mooring jewellery

Mooring Systems Vulnerability mooring legs

Terminations: Hawse tubes - highest tension with

additional bending, twisting stresses & link contact wear

Touchdown - heavy contact with sea floor containing rock of comparable hardness to steel -> severe localized wear

Touchdown - accelerated corrosion (aerobic), chain moves above & below mudline, parent metal exposure

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Mooring Systems Vulnerability fatigue

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Mooring Systems Vulnerability fatigue

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Mooring Systems Vulnerability fatigue

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Mooring Systems Vulnerability corrosion

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Corrosion comes in many forms

Design codes generally allow for

Mooring Systems Vulnerability - Ageing Assets

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Failure trends? recent incidents

Early life failures, design, manufacture, & installation

Reduction in mid-life

Increasing end of life failures; dominated by operational causes

(OTC 24181)

Mooring Systems Losses

Cascade Chinook - Loss 3/11

6.25 chain

Faulty weld repair causes fracture in single chain link

440T buoyancy tank supporting hybrid riser released

Chain vulnerable to hydrogen induced stress cracking post heat treatment

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Mooring Systems Losses

Recovered Subsea Arches

Gryphon - Loss 2/11

winds > 55 knots, ~12m waves, 10 leg mooring, 18 year old chain

Leading leg fails below design load

DP loses heading, FPSO turns beam on

21 degree roll, 3 more legs lost

180m movement damaging subsea kit (Maersk, 9/11)

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Mooring Systems Losses

Mooring Loss Statistics:

1 in 50 chance of a single line failure per floating asset per year. This equates to a 1 in 2 chance of line failure over a 25 (say) year design life.

1 in 350 chance of a multiple line failure (and/or infrastructure damage) per asset per year. 1 order of magnitude worse than industry (DNV) guidelines

Permanently moored assets only. Based on known losses. (2001-11, 23 documented failures inc. 8 system failures, 4 with riser failure).

Moving forward, these numbers are an underestimate. They do not recognise that all assets have continuously ageing mooring infrastructure.

Mitigation, to reduce the chance of failure, is essential.

Source: Mooring Integrity Forum, Monaco, 2014, OTC 24025

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Floating Unit Mooring Assessment (FUMA)

FUMA is an endorsement (not a warranty) for underwriters use.

Insurers have relied on Class & Operators to ensure adequacy of design & Mooring System integrity.

JRC mandated Engineering Sub-committee to investigate need for a formal process for Mooring System Assessment.

Reflects other JRC Assessment Processes, discretionary/voluntary, flexible.

Mooring Systems FUMA

Floating Unit Mooring Assessment (FUMA)

An underwriting tool, value-adding for assureds.

Structured consistently with other JRC survey documents eg CAR MWS & Well Plan review (Guidance Notes, Endorsement, Codes of Practice, Workscopes).

Consideration given to International Standards, Design & Operation Codes, Integrity Management Systems, Industry Best Practice.

Interaction with industry/operators and Oil & Gas Mooring Integrity Workgroup.

Mooring Systems FUMA

Floating Unit Mooring Assessment (FUMA)

Promote dialogue between Underwriters and Assureds, without dictating.

Report becomes Material Information & supports INFORMED underwriting decision making.

Assist Underwriters in better understanding the Assureds operational practices, integrity management and experience.

Enhance risk reduction for both Assureds and Insurers.

Mooring Systems FUMA

Intended for Moored Floating Units OTHER THAN MODUs.

Initial Screening Process (ISP) may indicate FUMA is not required (Generic considerations: Age, Design, Type, Class, Operating Standards)

Its a tiered process, light touch (Level 1) to full physical (Level 4).

Entry can be at any level, but with all preceding levels performed (assessing physical condition is important but understanding Assureds core philosophy is critical).

Mooring Systems FUMA getting started

Mooring Systems Risk Screening

Moored Risk Screening for FPSOs, FSOs, Spars, TLPs, SPMs & drilling units

Used across a Portfolio of Moored Risks (or Operators) to assist Underwriters with risk mitigation

Major incident likelihood (frequency) established by Naval Architects based on mooring complexity, age, design code, water depth, operational aspects, extreme environment vulnerability, inspection & monitoring etc

Risk Consequence considers insured exposure, field infrastructure - subsea architecture, adjacent platforms

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High: Intolerable Risks; mitigation is essential

Intermediate: Unacceptable, reduce to ALARP

Low: Acceptable: Consider ALARP

Level 1: Remote Desktop & Correspondence

Review of design limits, operational procedures & history against relevant IACS standards and industrys best practice.

Level 2a/2b: Attended Technical Review

(2a: Attendance Onshore, 2b: Attendance Onshore & Offshore)

Attendance by Mooring Assessors of onshore facilities and, if required, of offshore location.

Level 3: Physical Inspection

Physical inspection of moorings and third-party engineering as required.

Level 4: Detailed Physical Inspection

Physical inspection of moorings to higher specification and third-party engineering as required.

Mooring Systems FUMA assessment levels

Can be at any point in moored unit lifecycle (pre or post installation benchmarking, mid-life, if life extension planned).

Uses competent Mooring Assessors; any party on which Insurers & Assureds mutually agree.

Assessors may include Insurers internal engineering capability, and/or 3rd party (eg MWS with specialist mooring skills/experience, other specialist engineer).

Workscope is applied. Assessor delivers findings to both Assured & Insurers.

Mooring Systems FUMA when, how, who?

Mooring Systems FUMA - reporting

Mooring Systems FUMA - reporting

FUMA Level 4 Mooring Assessment - Tasks :

Pre-engineering to tailor inspection campaign

Offshore inspection campaign

2D/3D high def. focused visual inspections

Chain/wire/fibre measurement tools, 3D modelling

Review & report on risks associated with:

Historic mooring failures and blackouts

Operator Performance Standards

Original design analysis and assumed extreme environment

Operational philosophies and procedures

Inspection findings

Mooring Systems FUMA 4 typical tasks

FUMA Level 4 Mooring Assessment Tasks:

Review and report on risks associated with:

Reported operations & offloading against original design inputs

Mooring fatigue life re-assessment

Subsea architecture complexity & vulnerability

Collision risks & consequences floating, water column & seabed

Identify & report on gaps in operations, maintenance and inspection procedures

Recommendations for future inspection campaigns and wider mooring integrity management

Mooring Systems FUMA 4 typical tasks

Mooring Systems FUMA & Integrity Management

Ideally a Mooring Integrity Management System exists:

Part of Operator Safety Management System

Developed, owned & administered by Operator

Recognition that Moorings are Safety Critical

Key components:

System Description. Design, Manufacturing & Deployment

System Performance Standards (specific, measurable, agreed, realistic & timed)

Normal & Damaged Operational Procedures

Component Risk Review (ALARP)

Monitoring & Inspection driven by Risk Review

Feedback into Performance Standards

Suitable Tracking Systems to close out anomalies Source: Oil & Gas UK Report OP023 (2008)

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Most likely failure modes Identification of critical components Mooring Extreme & Fatigue Analyses Max. Operational & Survival Conditions

Pictures: BPP-TECH, 2012

Analysis of vessel loading conditions and hydrodynamics (Orcaflex)

Mooring Systems

Tools used - FUMA4

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FEA (Abaqus) for chain components In-house analysis models for damaged

wire ropes

Pictures: BPP-TECH, 2013

Analysis of structural integrity of critical components based on Welaptega inspection results and FEA

Mooring Systems

Tools used - FUMA4

Key high risk items identified in previous studies:

Failure to establish meaningful root causes of historic failures

Failure to implement recommendations made in internal accident investigations

Absence of line-tension verification systems

Lack of coherent emergency plans for mooring failures

Mooring inspections not conducted deeper than 30m (air diving limit)

Severe chain degradation known to operator No action taken to manage reduced capacity

Mooring Systems FUMA Identified Risks

Key recommendations made in previous studies:

Root cause analyses to be completed by competent persons

Engineering studies to account for real-world condition of system

Line-tension verification system to be installed as priority

Mooring line failures to be simulated in drills and findings integrated in emergency procedures

Comprehensive mooring inspection programme to be implemented

Take ownership of mooring integrity management dont rely on Class Societies to do this for you

Mooring Systems FUMA Recommendations

Development of effective mooring management strategies leading to:

Safer mooring systems, less prone to failure

Better early warning of mooring component degradation

Rapid identification of failures through improved monitoring

More efficient response of on-board and shore-based staff to mooring failure

Minimisation of mooring failure consequences

Reductions in number and size of insurance claims, improved insurance terms

Lower downtime and improved productivity

Improved industry reputation

Mooring Systems FUMA Benefits

Lessons Learnt

We NEED to know what we really have down there

How is it performing currently, how vulnerable is it

How much longer is it going to be fit-for-service.

We dont know what we dont know

and we wont know until

We make a conscious effort to go and find out!

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Thanks for your attention and

Questions?

d.brown@bpp-tech.com

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