Des i n i n f o r Tu r r et Mo o r i n S s t em Integrit ntegrity y – An Ope Opera rator tor’s ’s Pe Perspe rsp ective ctiv e
th
Ab A b er erd d een
• SOFE OFEC is is a busi usiness ess un unit of of MO MODEC –
,
,
• SOFEC SOFEC’s ’s Turr Turret et Moor Mooring ing Desig Design n and and Oper Operat atio ional nal Ex Expe perie rienc nce e from from 1988 1988 - 2010 2010 – 3 Permanent Internal Turret Mooring Mooring Systems – 5 Internal Disconnectable Disconnectable Turret Mooring Systems – 20 External Turret Moorin S stems 3 under construction
• Ov Over eral alll 220 220 year years s of of ope opera rati tion onal al life life – Average of 9 years / installed installed system – Longest duration: 22 years on site (Safer FSO, Yemen, 1988) – Shortest duration: 3 months months (Jubilee FPSO, Ghana, 2010)
• Focus on ma or turret moorin com onents
Swivel Access Access Stru tructu cture re Swiv wive el Stack Stack (Prod roduct uction ion//Cont ontrol rols) s) Manif nifold olds s + Pig Pig Launchin Launching/R g/Re eceiving E-Hous EHouse e + Sub Subsea sea Con Contr trol ols s + HPU HPUs s An A n c h o r L eg + Ris Ri s er Pu Pull l -In Eq Equ u i p m en entt ear n g
y s em
Chain Support s nc or
eg s
Risers & Umbi mbilic lica als
• Over Over 100 100 floa floati ting ng produ product ction ion syste systems ms in opera operati tion on sin since ce 1980’s • Larg Large e data databa base se of of anch anchor or leg leg sys syste tem m perf perfor orma manc nce e – Components will degrade over time –
vera sys ems ave proven o e re a e
– Have been cases of excessive excessive degradation/failure
• Currentl sufficient data from ermanent moorin s to allow identification of some common problems • Curr Curren entt subj subjec ectt of seve severa rall JIPs JIPs •
pec a
ess on on on
oor ng ng n egr y
• OTC 21012 21012 “Anchor “Anchor Leg Leg System Integr Integrity ity – From Design Design through Service Life,” Duggal & Fontenot
• Desig Design n Phi Philos losop ophy hy can Influ Influen ence ce longlong-te term rm inte integri grity ty • Code Code Requ Requir irem emen ents ts are are Min Minim imum um Requ Requir irem emen ents ts • Moor Moorin ing g ana analy lysi sis s and and des desig ign n – focu focus s on on sys syste tem m spe speci cifi fic c res onses/re uirements • Component de design – Corrosion and wear – to be expected – design for it – Mechanical design – easy to assemble; can disassemble disassemble – Material properties required & actual actual – manufacturing and testing
• Anchor Le “Failure” – t
icall at terminations
– Fairleads, terminations, connectors connectors
• Desi Design gn for for easy easy inst instal alla lati tion on and and main mainte tena nanc nce e – Poor installation can impact long-term long-term performance
Gene nera rall Obs Obse erv rva ati tion ons s for f or Lo Lon n -Term Desi n of o f Anc A ncho horr Le Le Systems
• Shou Should ld two two anch anchor or legs legs dama damage ged d be cons consid ider ered ed? ? • Pro er desi n for wear and corrosion • Keep Keep the the anc ancho horr leg leg conf config igur urat atio ion n sim simpl ple e • Proper Proper analy analysi sis s and and desi design gn at fairl fairlea eads ds and and con connec necti tions ons • Out of Sight – Out of Mind? – Good inspection and maintenance maintenance procedures essential
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• Desig sign/Size for “z “zero ero” we wear – Bearing design does allow for some wear
• Isol Isolat ate e bea beari ring ng fro from m vess vessel el & tur turre rett resp respon onse ses s • Use Use of of a rel relia iabl ble e aut autom omat atic ic lubr lubric icat atio ion n sys syste tem m • Port Ports s for for sam sampl plin ing g gre greas ase e over over the the ser servi vice ce life life – Provides input on wear & water / dirt dirt ingress
• Ensur Ensure e Oper Operat atio ion n and and Maint Mainten enanc ance e proc proced edure ures s are are foll follow owed ed
12.5 12.5 Meter Meter Segmented Segm ented Bearing Beari ng
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.
Largest available available in contin uous ring • Largest design
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• Layo Layout ut of pip pipin ing g and and equi equipm pmen entt acco accoun unti ting ng for for repa r ma n enance access an poss e expans on • Desig Design n pip piping ing and manif manifol old d sys system tems s for for flexi flexibi bilility ty •
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• Desig Design n swi swivel vel stack stack with with redu redunda ndancy ncy & ease ease of Mai Mainte ntena nance nce – Include spare paths when when possible – Allow for re-routing through Spare/Test Swivels Swivels
• Leak recovery system • Swive Swivell acc access ess struc structu ture re with with hoist hoists s and and handl handlin ing g equip equipme ment nt • Ac Acce cess ssib ible le layd laydow own n area areas s on on tur turre rett / vess vessel el
INNER HOUSING Seal Plate
Sealing System Bearing Cover
Barrier Seal
ear ng
Inlet/ Outlet
HOUSING
Barrier Seal Prima Primarr Second Secondar ar Sealing System
Inlet/Outlet
Swiv wive el Sta Stack ck – Typic ypica al Compo Compone nents nts • Fiber Op Optic Ro Rotary Jo Joints –
Optical Communication: Turret, Subsea
• Utility Sw Swivels: – –
Hydraulic Fluids: Sub-sea Controls, SDV Chemical Injection Fluids: Corrosion, Wax, Scale Inhibitors,
–
Utility Fluids: Service Air, Instrument Air, Nitrogen, Water, Vents
• Electrical Sl Slip Ri Rings – –
ow o age e um o age: urre , u sea Signals: Turret, Subsea
• Toroidal Swivels: – – –
Production fluids Water Injection Gas Lift, Injection, Export
• Elec lectrical cal Pow Power Slip lip Ring ing – Subsea Pump/Well Head Platform Power
Spare Seal Tray Between Each Toroidal oroidal Swivel
Terra-Nova
Barracuda
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Seal carrier carrier of upper upper toroidal swivel lowered to gain access access for replaceme replacement nt of the t he seals. seals. Seal Carrier of lowermost access to th e seals. seals.
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Fluid Fluid Seep Seepin ing g betw betwee een n prima primary ry and and secon seconda dary ry seal seals s can be detected and monitored at the Leak Recovery ane .
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Flui Fluid d is is cap captu ture red d in in the the Leak Leak Reco Recove very ry Tank Tank..
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Reco Recove vere red d fluid fluid is pump pumped ed back back from from the the lea leak k reco recove very ry an n o pro uce u nes.
Leak Detection Panel
Leak Recovery Tank
Service Tubing on Swivel
Leak Recovery Recover y Pump
• The The desi design, gn, fabri fabrica catio tion n & inst install allat ation ion of the the syst system em inf influ luenc ences es lon -term erform ormance nce/relia liabilit – Many cases of component component failure due to poor design/installation design/installation
• Consi Conside derr syste system/l m/loc ocati ation on speci specifi fic c design design crit criteri eria a • Prop Proper er and and wel welll plan planne ned d insp inspec ecti tion ons s are are impo import rtan antt – Require more specific requirements requirements for operations to follow –
• Spari Sparing ng phi philos losoph ophy y incr increas easin ingly gly impor importan tantt as ass assets ets incre increase ase • Maintenance! – When excessive degradation or other issues are observed – fix or replace it!
