Brazil OG Issue 2

8/12/2019 Brazil OG Issue 2

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Inside

Brazil oil & gas

EPRASHEED ign r ie

2006 - Issue 2

Oil Self-sufficiencyPetrobras Presidentinterview

Deepwater Feature


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EPRASHEED

ign r ie

www.eprasheed.com

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Brazil oil & gas

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President Lula starts P50 production.Photo: Steferson Faria


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3Brazil Oil and Gas Issue 2


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4 Brazil Oil and Gas Issue 2

EditorsWajid RasheedGeorge Hawrylyshyn (Brazil)John Bradbury (Intl)

JC Cunha (Technology)Mauro MartinsMajid Rasheed

PublisherCEO Wajid [email protected]

Brazil Oil & GasLondonEnglandTel: (44) 1753 572257

Brazil Oil & Gasc/o EasylinePrado Junior, 78Copacabana - RJTel: (55) 21 2275 5090

Representativesn Ana [email protected]: (55) 21 9714 8690n Edvar Rodrigues Maca

Tel: (55) 21 9717 0565n Graziele SimesTel: (55) 21 9203 3156n Monica Placido, [email protected]: (55) 21 9213 0629

NOTE FROM THE CEOHistoric Milestone - Brazil reaches Oil self-sufficiencyWajid Rasheed (CEO and Founder)

PETROBRAS PRESIDENT INTERVIEWBrazilian oil self-sufficiency and beyondMajid Rasheed (Editor, International Markets - Brazil Oil and Gas, London)

DEEPWATER - MINAMI INTERVIEWPROCAP 3000 Kazuioshi Minami InterviewWajid Rasheed

DEEPWATER - WELL CONTROLReducing Risk in Mexilho DevelopmentAntonio C.V.M. Lage et al., Petrobras

OFFSHORE - HEAVY OIL TECHNIQUESUncertainty Assessment Using Experimental Design and Risk AnalysisTechniques, Applied to Offshore Heavy Oil RecoveryJ.W. Vanegas Prada, J.C. Cunha and L.B. Cunha, U of Alberta

DEEPWATER WELL CONSTRUCTIONDeepwater FeatureWajid Rasheed

SUBSEASubsea Equipment, Risers & Pipelines

PETROBRAS TRANSPORTE SA DIRECTOR MARCELINO GUEDPipelines and Terminals

SPONSORS

VETCO GRAYSlender Well Economical Wellhead System for Ultra Deep WaterCarlos Eduardo M. Sequeira and Bruno Schauerte, Vetco Gray Brasil

TESCOPetrobras Sets Record Casing Run in Extended Reach WellClovis Neves, Tesco do Brasil and Vicente Abel Costa, Petrobras

Contents

Brazil oil & gas

EPRASHEED

ign r ie

2006 - Issue 2

Representatives

Houston William Bart GoforthTel: (1) 713 304 6119

North SeaJohn FergusonJohn Ferguson AssociatesTel: (44) 141 632 8694

ArtistsAlexandra BrunaNeuza MarcondesJair MendesLayout: Manifesto VisualCristiana Ribas


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With an average production of5,000 bopd exceeding demand,Petrobras and Brazil reached the his-toric milestone of oil self-sufficiencyon April 21st 2006. By producing1,795,000 bopd, Aprils productionexceeded the previous highest pro-duction by 37,000 bopd.

Within 20 years, Brazils dependenceon oil imports for national demandhas fallen from 80% to 0%. Tisplaces Brazil, as far as oil productionis concerned in a select and fortunateposition as it does not have to competefor crude on international markets.

In a ceremony on the P-50 Platform,both the Presidents of Brazil andPetrobras celebrated the event byhighlighting the signicance of self-sufficiency as a nancial shield fromoil-price volatility. Now, Petrobrasmust maintain a rigorous program ofreserves replacement and productionin order to sustain self-sufficiency.

Self-sufficiency shows just how farthe Brazilian oileld has come alongsince the market opened up in the

late 90s. Majors come and go; butthe real EP constant is Petrobras which has driven the industry toovercome the twin challenges ofdeepwaters and heavy oil.

NOTE FROM THE CEO HISTORIC MILEST

Tis has been possible due to themyriad oilworkers from both theservice companies and operatorsthat make production targets hap-pen. In this way, self-sufficiency isalso a tribute to these people, Brazil-ian and visitors.

Our cover shot reects this with agroup photo of Petrobras and con-tractor workers in front of the P-50platform.

It is satisfying to see issue 2 of BrazilOil and Gas with such a strong edi-torial line-up. Our cover features arean extensive interview with Jose Ser-gio Gabrielli and a deepwater tech-nology feature. Te Petrobras Presi-dent took time out during a recentvisit to London and met with ourinternational markets editor, Majid

Rasheed.

Te extended deepwater feature in-cludes drilling, subsea and produc-tion analysis as well as interviews withPROCAP-3000 Manager Minami.

We also have a special interview withMarcelino Guedes, Pipelines and

erminals Director, Petrobras.

Looking ahead to future issues, thereis an interview with Jose Luiz Mar-cusso, Executive Manager of thenewly formed Santos Basin Busi-ness Unit-based in Sao Paulo. Tereis also an extended interview withRenato Bertani, President PetrobrasUSA. And of course our usual tech-nology features.Brazil Oil and Gas will be publishedquarterly, this is in accordance withthe interest shown in the magazineby both Petrobras and other com-panies within the sector. Brazil Oiland Gas forms part of EPRasheedssignature series a commitment toproviding our readers with insightto handpicked key global oil and gasmarkets.

Wajid Rasheed,CEO and Founder,Brazil Oil and Gas.

Brazil Oil and Gas forms partof EPRasheeds signatureseries a commitment toproviding our readers withinsight to handpicked key-global oil and gas markets.

A tribute to the myriad workers - Brazilian and

visitors - that make production happen.

BrazilianOil self-sufficiency

President Lula wets his palms with Brazilian crude.Photo: Steferson Faria, Petrobras.


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Self-SufficiencyQ: Brazil Oil and Gas Brazil andPetrobras have reached an historicmilestone, what does self-suffi-ciency represent? A: Jose Sergio Gabrielli First of all,self-sufficiency means we can providethe necessary amount (of oil) for theconsumption of oil products in Brazil.

Second, over a long-term view, it al-lows the possibility of growth of pro-duction, and management of reserves,because, as you know, oil is a long-term business, not short term. Tird, is

During Brazils recent state visit to the UK, Petrobras President, Jos

Sergio Gabrielli, gave a private presentation to Financial Analysts Deutsche Bank, London.

According to Deutsches Head of Latin America Market Equities Kerim Derhalli Petrobras of the most exciting investors in the oil and gas sector and one of the leading lights in the sectFollowing the presentation, Brazil Oil & Gas enjoyed Mr Gabriellis company in an exclusive inand gained a privileged insight into the world of Petrobras.

By Majid Rasheed (Editor, International Markets - Brazil Oil and Gas, London)

the economic benet, so that interna-tional price uctuations do not affectthe Brazilian domestic market. Tis isvery important for us.

Next decadeQ: Brazil Oil and Gas Petrobrashas evolved immensely over thelast 10 years from state owner-

ship to market privatisation. Whatdoes the next decade hold for thecompany? A: Jose Sergio Gabrielli Up to nowwe have been focusing on production,

in the next few years we are goingto increase investment and focus onexploratory activities. We have somevery large national Projects planned for each consecutive year until 2010,and the following projects are nowin their nal stages: Albacora Leste, Jubarte, Piranema, Manati, Peroa-Cangoa, and Golnho. Petrobras willalso become more involved with theBio-Diesel Programme. Not from an

agricultural point of view ie buyingland, but concentrating on the ren-ing, production and exportation ofBio-Diesel.

Brazilian oilself-sufficiencyand beyond

PETROBRAS PRESIDENT INTERVIEW


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Investment StrategyQ: Brazil Oil and Gas What isPetrobras business investmentstrategy? A: Jose Sergio Gabrielli Petrobras

will be investing considerably in keystrategic areas of its business, includinginternational activities, and a total ofUS$ 56.4 billion has been set for the 2006 to 2010 period. A few of Petro-bras future strategies are that we havean Investment Plan for the 2006-10 period which will see US$ 56.4 billioninvested. (See Investment Box Below)

E & PQ: Brazil Oil and Gas What arethe acquisition/major E and Pfronts for Petrobras? A: Jose Sergio Gabrielli Tere havebeen no company acquisitions of late.However, our global activities are con-tinuing to expand. Petrobras won a bidto explore and produce in urkey andrecently acquired 2 blocks for explora-tion there. Since establishing a footholdin China, with the May 2004 inaugu-ration of its office in Beijing, Petrobrashas been broadening its map of inter-national activities through agreementsand signed contracts in seven countries,across three different continents.Te scenario looks promising off theNorthwest coast of Libya, in the Medi-terranean Sea, while new fronts are be-ing opened up in the American sector of

the Gulf of Mexico, off the anzaniancoast, in Colombian waters in the Ca-ribbean, in the Persian Gulf and evenin the interior of neighbouring countryUruguay. We have increased our produc-

tion signicantly, and Domestic produc-tion will grow at an average of 6.4% per year, from 1,684 boed in 2005 to 2,300boed in 2010. From 2006, lightoil production from new projects willsurpass 150,000 bpd and crude oil ex- ports will reach 522,000 bpd.From 2002 to 2005, there has been a12% increase in production. We havenow seen the P-50 Albacora Leste (cap.180,000 bpd) platform start production

and later this year further production isslated for P-34 Jubarte (cap. 60,000bpd), FPSO Capixaba Golnho (cap.100,000 bpd) and the SSP 300 Pir-anema (cap. 20,000 bpd).

New findsQ: Brazil Oil and Gas What havebeen the new nds booked? A: Jose Sergio Gabrielli We announceda new nd in the Campos Basin a fewmonths ago. It is in a deeper area thanbefore, and although it is not large it isa signicant discovery nevertheless. Weare now in a commercialisation stage ofdifferent elds on a continuous base. Last year our reserve replacement ratio wasmore than 1 barrel per barrel used in our production.

ReservesQ: Brazil Oil and Gas What isPetrobras reserves to productionratio? A: Jose Sergio Gabrielli We have a

fairly stable reserve to production ratio.Te Reserve to Production ratio is 19 years, and we want to keep it muchmore beyond 2010, to 15 years

Lifting CostQ: Brazil Oil and Gas What isthe average Lifting Cost for Oil &NGL? A: Jose Sergio Gabrielli In 2005 thelifting cost was US$ 5.73 against US$4.28 in 2004, an increase of 34%.In Reais, this same cost was R$ 13,83against R$ 12,30 in 2004, representinga 12% increase. Lifting cost increasedin 2005 due to the appreciation inthe Brazilian Real against the Dollar,higher chartering fees for rigs linked toincreases in the international price ofoil, higher expenses for transportation,underwater operations, restoration andmaintenance, and chemicals used tounlock and eliminate toxic gases andincreased salaries and benets resulting from the collective labor agreements for 2004/2005 and 2005/2006.

PlatformsQ: Brazil Oil and Gas What plansare there for new platforms/instal-lations? A: Jose Sergio Gabrielli We have

several extensive projects coming alongin 06, 07, 08 09, and 2010. Also, P-53 and P-54 are currently under bid-ding and we have started the bidding process for P-55 and P-57.

GasQ: Brazil Oil and Gas What partdoes Gas play in the companys plans? A: Jose Sergio Gabrielli Gas playsa denitive part in our plans. For the

rst time, we have a very strategic plan for development of non-associated gas,now going to start producing a largevolume of non associated gas from theSantos Basin, which was the rst major

GABRIELLI

Petrobras investmentE&P - USD 34.1Billion (60%), Downstream - USD 11.4B (20%), G&E - USD 6.7B(12%), Petrochemicals - 2.1B (4%), Distribution - 1.0B (2%), Corporate - 1.1B (2%)

Expected Investments in 2006 - US$ 15.4 billion (R$38.5)

E&P 49%, Downstream 13%, G&E 17%, Distribution 2%, International 16%, Cor-porate 3%

DownstreamUS$12.9 Billion Refining / Pipelines, Terminals & Transport / Ship Transport / Pet-rochemicalUS$8 Billion in refining Diesel & Gasoline Quality / Extension / Maintenance &HSE / Conversion [using R$2,50 per USD]


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discovery for natural gas. As you prob-ably know, the rst major discovery for oil was the Campos Basin in Rio,which holds 85% of reserves. Te threemajor areas are located thus Cam-

pos Rio, Santos South of Brazil,Espirito Santos in North. Tese lo-cations across Brazil mean we have awider area for production.

R & DQ: Brazil Oil and Gas Dur-ing the time when many IOC cuttheir R&D functions to reducecosts, Petrobras invested more inits R&D facilities and pioneered

aspects of deepwater and heavy oilproduction. What are the futureplans for R&D? A: Jose Sergio Gabrielli We believewe are at the leading edge of offshoredeep water production, and we want

to maintain this position. We are in-vesting considerably in this area in or-der to ensure we secure our position atthe forefront of this area. One of themain plans, and strengths, of Petro-

bras is continual investment. Particu-larly so in R&D and the BrazilianLabour force that we have: raining,Research and Development, and longterm career development & oppor-tunities, are all very important forPetrobras.

Q: Brazil Oil and Gas Do yousee Petrobras technology as a com-petitive advantage over IOC when

dealing with potential foreignpartnerships ie when bidding ornegotiating for new acreage? A: Jose Sergio Gabrielli Yes, I thinkin some countries it is advantageous,however in other countries the bid pro-

cess is more price oriented not technol-ogy oriented. So, in some countries tohave good technology is benecial, butnot in all countries.

Q: Brazil Oil and Gas What isthe role of Cenpes, the R&D Cen-tre in Rio? A: Jose Sergio Gabrielli Cenpes hasbeen an important economic inu-ence, helping the countrys balance of payments, for over 30 years. It has con-sistently achieved results with foreignreserves regarding technical assistance, purchasing designs and paying royal-ties. Cenpes also plays an important

role in using raw materials, equipmentand material manufactured in Brazil,and providing a genuine incentive forBrazilian manufacturers and compa-nies to provide technical consultingservices.


Cenpes, the R&D centrein Rio, has played a veryimportant role in theprogression of Petrobras,its personnel and manyrelated activities. Photo: Steferson Faria, Petrobras.


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Cenpes coordinates three strategic projects, which are among the tech-nological priorities of Petrobras: ech-nological Innovation and AdvancedDevelopment in Deep and Ultra-deep

Waters, the Advanced Oil Recoveryand the Strategic Rening echnolo- gies Development. Another outstand-ing technological program run byCenpes is the Offshore echnologyProgram, to upgrade offshore explora-tion, drilling and production opera-tions. Cenpes also undertakes projectsin partnership with other oil corpora-tions and research and developmentcenters overseas.

PeopleQ: Brazil Oil and Gas What isthe secret to Petrobras success? A: Jose Sergio Gabrielli People mostdenitely, as well as necessity, tech-nology, and successful management.Tere are also three signicant areas,which are not secret, but they are themain driving forces for Petrobras.First, the commitment to the domes-tic market; in the beginning Petro-bras had the responsibility to provideBrazil with oil products. Second, wehave set targets that we have to meet,and in order to do that we consistent-ly invest. Petrobras has always beencommitted to creating employmentopportunities. Tere will be 10,000new workers brought in from 2006 2008, across all our areas and de-

partments.We have a very intensetraining system, and we have a verydedicated, motivated labour force. Itsamazing! If you visit our R&D centreor go to our sites you can see that the

Downstream Strategies Domestic oil production will exceedthroughput In 2010 oil products sales will be

equal to throughput Increase of the domestic oil partici-pation in throughput, reaching 91%in 2010

South American IntegrationGas Pipeline Southern ConeVenezuelan - Brazil GasPipeline.

vast majority of personnel are Brazil-ian, trained by Petrobras.Te third thing is to remain adaptableand keep a very exible adjustment tothe conditions of the market. Petrobrasreally tracks the market, and different phases of the oil market in the worldand in Brazil.

TrainingQ: Brazil Oil and Gas What

training programs does Petrobrasoffer and what investments are be-ing made? A: Jose Sergio Gabrielli Althoughwe have Petrobras Universities, we also

train people in the best place wherewe can nd the work, providing in-tensive training programmes for ourdedicated and motivated labour force.

raining, R&D, long-term career de-velopment and opportunities are allvery important for Petrobras. Te two Petrobras Universities are inSalvador and Rio. Cenpes, the R&Dcentre in Rio, has played a very important role in the progression of Petro-

bras, its personnel and many relatedactivities.Petrobras is investing in each and everyarea of personnel, focusing especiallyon raining and R&D

GABRIELLI


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RefiningQ: Brazil Oil and Gas Whatplans does the company have fornew reneries? A: Jose Sergio Gabrielli Petrobras hasapproved the purchase of a renery in

exas, continuing its expansion in theUS.

RefineriesQ: Brazil Oil and Gas What are

Petrobras total number of rener-ies? A: Jose Sergio Gabrielli Te rener-ies are the following:1. Landulpho Alves Renery (Rlam) Mataripe, Bahia / 2. Presidente Bernardes Renery(RPBC) Cubatao, Sao Paulo / 3. Duque de Caxias Renery (Reduc) Campos Eliseos, Rio de Janeiro /4. Gabriel Passos Renery (Regap)

Betim, Minas Gerais /5. Alberto Pasqualini Renery (Refap) Canaos, Rio Grande do Sol /6. Paulinia Renery (Replan) Pau-linia, Sao Paulo /

7. Manaus Renery (Reman) Manaus, Amazonas /8. Capuava Renery (Recap) Maua,Sao Paulo /9. Presidente Getulio Vargas Renery(Repar) Araucaria, Parana /10. Henrique Lage Renery (Revap) Sao Jose dos Campos, Sao Paulo /11. Asphalt plant in Fortaleza (Asfor) Fortaleza, Ceara Petrobras indus-trial plants also include two nitrogen fertilizer plants (Fafen) in Laranjeiras(Sergipe) and Camacari (Bahia).12 US, exas, Pasadena renery.

Q: Brazil Oil and Gas What Awards has Petrobras received re-cently? A: Jose Sergio Gabrielli Global rans- parency Award 2005, and O C Award for two consecutive years. Our Directoris going to give the keynote address at

the O C Award. As well as receiving prestigious Awards from within the Oil& Gas sector, Petrobras has also beenrecognised for its on-going commitmentto social programmes. It secured 2nd

place ranking in the Young CitizenshipNetwork Ita-Unicef Award.Petrobras competed with 1,682 otherregistered initiatives of Brazil, and wonthe award for, among other things:

Displaying commitment with the de-velopment of children and teenagers; Stimulating learning in publicschools; Respecting diversity and the promo-tion of equality between youngsters; Developing projects and with thecommunity and schools.

Q: Brazil Oil and Gas DoesPetrobras produce any other en-

ergy fuels? A: Jose Sergio Gabrielli Yes, In addi-tion to helping to distribute anhydrousalcohol, Petrobras also produces shale oil,similar to petroleum. Brazil has the sec-ond largest shale reserve in the world.

Environmental & Social Re-sponsibilityQ: Brazil Oil and Gas Can youdiscuss Petrobras major social re-sponsibility projects? A: Jose Sergio Gabrielli Yes, weare the largest contributors to culturein Brazil! We have a large number ofsocial projects. Tere are 2 different programmes focusing on social respon-sibility, Petrobras Sociale & Fome Zero(Zero Hunger). Petrobras also has avery large environmental programme.Our main focus over the last 2 years wasthe Water Management programme,which we continue to nance.Petrobras also sponsors the followingenvironmental education projects:Brigada Mirim Ecolgica (ChildrensEcological Brigade) in Angra dos Reis(Rio de Janeiro state), Cetaceans, onthe Rio de Janeiro state coast JubarteWhale, in the Abrolhos archipelago inBahia.Te company also supports Ibama proj-

ects, such as the preservation of MontePascoal National Park and the amar project that protects sea turtles.Petrobras is considered one of the mostimportant sponsors in Brazil, and also

Capuava Refinery in Sao Paulo.Photo: Steferson Faria - Petrobras.



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Brazil Oil & Gas has always been im-pressed by Petrobras' transparency,the way it handles its business andcontinually invests to help reducethe environmental effects of its busi-ness while building local infrastruc-ture. This goes back to 1999 whenWajid Rasheed first started working

with Petrobras. Brazil Oil and Gaswould like to acknowledge AnamariaRossi for her help with this editorialfeature.

Second, over a long-term view, it allows thepossibility of growth ofproduction, and man-agement of reserves,because, as you know,oil is a long-term busi-ness, not short term.

First of all, self-suf-ficiency means we canprovide the necessaryamount (of oil) for theconsumption of oil prod-ucts in Brazil.

Third, is the economicbenefit, so that inter-national price fluctua-tions do not affect theBrazilian domesticmarket. This is veryimportant for us.

supports cultural, sports and commu-nity projects.Petrobras also supports Te Young Cit-izenship Network, promoted by Asso-ciao Imagem Comunitria (AIC).

Q: Brazil Oil and Gas Apartfrom the regulatory framework what does Petrobras do to controlthe effect of its activities on the environment? A: Jose Sergio Gabrielli Petrobrashas a preventative approach regardingthe environment. We recognise it canbe a risky business, and we place theutmost importance on environmental

responsibility to avoid the possibility ofaccidents Petrobras has invested in many areasincluding Hardware ie pipelines andthe latest equipment, but most impor-tant thing is to have a preventativeapproach. We have to always keep inmind that we are dealing with a veryrisky business, and the potential tohave an environmental incident, andwe have to avoid the possibility of anyaccidents at all costs.Over the last four years, after 2001,we have invested in environmental prevention. Te environmental Pro- gramme of Excellence helps manageour systems to minimise leakage andthe impact on our environment. Wehave a very good track record, in thelast 4 years we have reduced dramati-cally our leakage.

Gabrielli on oil

self-sufficiency

GABRIELLI


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Q: Brazil Oil and Gas - What tech-nologies would you highlight asbeing fundamental to maintainingself-sufficiency? A: Kazuioshi Minami - KeepingPetrobras production above Brazilianlong term demand will require busi-ness investments in exploration, new production development projects, andthe proper operation of existing elds tohalt their natural decline. echnologywill be needed in all the three fronts. Iam not covering technology related doExploration because it is not my area

of specialization.For eld development projects, an areathat Procap-3000 has a strong inu-ence on, I believe well constructiontechnology, which allows large bore

size and long horizontal stretches, pre-cisely placed in the reservoir, is a key tothe success of reaching high throughputand good reservoir sweep. o do that,it is very important not only to havethe technologies but also to have a wellintegrated technical team, composedof geologists, geoscientists, reservoir en- gineers and drilling experts, workingtogether to design and execute the pro-duction and injection wells accurately.Drilling technology has advanced somuch that today it is possible to drill40,000 bpd producers and water in-

jectors offshore Brazil, something un-thinkable 15 to 20 years ago. Anothertechnology that evolved signicantly isthe hull design and mooring for oat-ing production units. Te new hulls

and mooring are built to reduce move-ments, and thus, increase life span ofrisers, and to increase load capacityof the unit so that we can have larger processing plants and larger numberof risers. Te mooring technology weuse today, based on polyester ropes andtorpedo piles, is believed to support in-tallation of oating units in water asdeep as 3.000m.For elds already in production, thekey is to keep or increase througput byusing more efficient articial lift andsubsea boosting. For heavy oil andhigh water cut wells lifting the liquidstream becomes of paramount impor-

tance and these two technology aremuch better than gas lift from hydrau-lic performance. It will be importantto develop technology to increase runlife and decrease replacement costs.

MINAMI INTERVIEW

PROCAP 300Kazuioshi Minami PROCAP 3,000Coordinator spoke with BrazilOil and Gas about Petrobras'ongoing technology commitment

for deep and ultra-deepwaters.

By W. Rasheed


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3. Deep Horizon Drilling4. Wellbore Stabillity5. Well completion equipment6. Deep and Ultra-deep Water Flow Assurance

7. Articial Lift and Subsea Boostingin deep waters8. Flexible Riser Systems9. Rigid Risers Systems10. Alternate Risers Systems11. Subsea Equipments for 3.000mWater Depth12. Non-conventional Subsea Systems13. Dry Completion Units for Deepand Ultra-deep waters14. Ultra-deep water mooring

15. Ultra-deep water hull concepts16. Meteocean, geological and geotech-nical Data AcquisitionTere is also the follow up on the Deep-star Phase VII project.

Q: Brazil Oil and Gas What arethe new projects? A: Kazuioshi Minami - Tese are re-lated to mid-term E&P domestic andinternational scenarios. For example,in Flow Assurance, we are increasingour efforts towards gas and condensatesin deep waters, wax and hydrate con-trols for light crudes in ultra-deepwaterscenario. In the drilling area, we haveadded projects for hard formation drill-ing and drilling sub-salt. I can also saythat to overcome overpriced rig costs,we are conducting several projects suchas light interventions techniques, cableinstalled subsea equipment, and hori-zontal subsea trees for electrical submers-ible pumps. We are also looking at each project for the possible Gulf of Mexicoscenario application, making the neces-sary adjustments.

Q: Brazil Oil and Gas How willPROCAP3000 technologies be ap-plied to new Santos Basin? A: Kazuioshi Minami - Developing

Santos will be a huge task to be car-ried out by the newly formed PetrobrasSantos Basin Business Unit. Te basinis relatively untouched with elds sim-ilar to those of the Campos Basin, such

as the heavy oil reservoirs in ultra-deepwaters, but also with several elds verymuch different.We are going to be developing gasand condensate elds such as Mexil-

ho, using multiphase ow in largediameter and long pipeline to shore(34in, 140km long). Since this trunk pipeline is going to operate at low owrates for a couple of years, a lotof issues related to pigging and slugcontrol will have to be dealt with. Another concern is the subsea devel-opment of Mexilhao, comprised oflong tie backs to the host platform inshallow waters, which will require

special care concerning MEG (mono-ethilene-glycol) injection to the subseawells, for hydrate prevention, and itsrecyling at the host plant.We have already discovered large vol-umes of heavy to extra-heavy crudein ultra-deep waters in Santos Basin.Terefore, in addition to the Pro-cap-3000 projects, we are countingon technology being developed by thePropes - Offshore Heavy Oil echno-logical Program, similar to Procap,started three years ago.Finally, we have great potential for lightcrudes from very deep reservoirs, belowthe salt layer, 6000m or deeper from sealevel. Tey are very tight reservoirs thatwill require special wells, long hori-zontals, fractured or multi-lateral. TeProcap-3000 systemic project Deep Ho-rizon Drilling is very important for thatmatter. At the end of 2005 we have alsoincluded one systemic project under thePravap (Enhanced Oil Recovery ech-nological Program) dedicated to LowPermeability Carbonate Reservoirs ofSantos Basin.In summary, Santos Basin will posea lot of challenges which will requireresults from Procap-3000, Propes andPravap to be successful.

Editor's note:Kazuioshi Minami was recently named byPetrobras as the Drilling Manager for theSantos Basin Development. His successorat Procap 3000 is Mauricio Werneck.

Petrobras has two major initiatives for mature elds, the rst one beingthe Enhanced Oil Recovery echno-logical Program, called PRAVAP, andthe corporate RECAGE program toseek highest recovery factor from eldsin advanced recovery stages. Te rstone is technology oriented, run fromCENPES and involving all E&Pbusiness units, and the second is busi-ness oriented, run from headquarters,to implement necessary investments tokeep the mature eld alive as long as possible.

Q: Brazil Oil and Gas What are

current PROCAP 3000 Projects? A: Kazuioshi Minami - Te systemic projects are:1. Wellbore Safety 2. Drilling Equipment

The Procap-3000 compris-es 17 systemic projectsand 93 projects. We spentaround USD 30 million in2005 but we expect to in-crease this number by 30%in 2006.

A good portion of thisamount will be directed toprojects for well construc-tion and subsea equipmentdevelopment.

Petrobras overall R&Dspending is increasingsteadily.2002 - US$ 147 million2003 - US$ 201 million2004 - US$ 247 million2005 - US$ 399 million2006 - approx. US$ 500 mil-lion (budget)


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VETCO GRAY

Tis article is based on the originaldevelopmental work conducted aspart of a technological agreement

with Petrobras to design and test a

13 Subsea Slender Wellhead Sys-tem for drilling wells in deep water.It describes the technological chal-lenge and the solution adopted foreach of the principal componentsduring the design phase and how in-terfaces were dened. It also explainsthe various stages of the prototypetest program and outlines the instal-lation of the rst system in the eld.Te article also describes how theSlender Wellhead System ts into atypical Slender Drilling System.

Slender Well Economical

Wellhead System forUltra Deep WaterBy Carlos Eduardo M. Sequeira and Bruno Schauerte - Vetco Gray Brasil

Critical areas identied included thecasing hanger load shoulder, the cas-ing hanger neck, the MS-1 and MSEseal elements and the wear bushing

lockdown mechanism.

MWP. Figure 1 exhibits the well-head system stack-up. Te low pressure wellhead housingis prepared for attaching a 30 con-ductor string to provide the struc-tural integrity of the well.

Te housing provides a dual socket,preloaded, fatigue-resistant connec-tion between the low pressure hous-ing and the high pressure housing

with a capacity of 2.4MM ft.-lbs.identical to the 16-3/4 and 18-3/4Petrobras system. Te high pressure housing is pro-vided with a 16-3/4 external H-4mandrel prole and a standard 16-3/4 VX seal preparation to interface

with existing 16-3/4 BOP equip-ment.Te 16-3/4 housing ID has beenmaintained on the upper end of thehousing with a prole to permit theuse of an existing 16-3/4 cam-actu-ated running tool, reducing to a 13ID to set the casing hanger. wo sealbands of parallel wickers are pro-vided to set, lock and seal up to twocasing hangers and seal assemblies.Te internal diameter allows thepassage of a 12-1/4 bit with boreprotector in place.Te lower end of the high pressurehousing is provided with an exten-sion for the 13-3/8 casing string. Te system is rated to 1,530,000pounds axial load, which corre-sponds to 400,000 pounds of casing

weight plus a 10,000 psi pressure

end load.High Pressure HousingTe internal load shoulder to landoff the primary casing hanger was

State-of-the-art engineering tech-nology and computer modeling wasused to design the system.

Slender Wellhead SystemOverview Slender Well conguration: 30x 13-3/8 x 9-5/8 for 10,000 psi

The Slender WellheadSystem permits the use ofsmaller or older genera-tion drilling rigs (fittedwith Slender Drilling Sys-tem) in deeper waters,reducing the overall costof the drilling operation.In todays tight rig marketit opens up new options.

Slender Wellhead TechnologyChallengeSlender Wellhead technology isbased on the eld proven 16-3/4and 18-3/4 MS-700 system.

Because of the reduced diameter com-pared to an 18-3/4 or 16-3/4 sys-tem, various design challenges wereidentied and required innovative so-lutions for both equipment and tools.

To date, Vetco Gray hasdelivered 40 SlenderSystems and installed 12systems for Petrobras.


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PAID ADVERTISEMENT

recognized as extremely critical to theoverall integrity of the system, due tothe high bearing load combined withthe inherent diameter restrictions ofa 13 system. Tis load shoulder in-

terface therefore was extensively ana-lyzed and veried with FEA.Te load shoulder provides the con-tact area in the wellhead housing formating of the casing hanger loadshoulder, achieving a system capac-ity of 1,530,000 pounds without theuse of a separate load insert ring.

A specic lock-down groove is pro-vided below the load shoulder forengagement of the spring loaded

pins on the casing hanger.

Casing HangerTe casing hanger was optimizedusing FEA to maximize the radialand compressive load capacity of thehanger neck for the interface withthe Universal Running ool (PAD-PR ) and the MS-1 seal element.Te load shoulder is provided witha continuous 360 deg. contact areato maximize the load capacity of thesystem with generous ow-by area of9.6 sq. inch and for a maximum par-ticle size of 0.7 inch.Spring loaded pins are provided toengage in the lock-down groove onthe high pressure housing to conrmcorrect positioning of the hanger.

A generous debris collection area is pro-vided below the metal seal element.Te hanger internal drift diameter of8-3/4 allows passage of an 8-1/2drill bit.

13 MS-1 Seal AssemblyTe 13 MS-1 metal seal is designedto meet the rigors of offshore drill-ing.It consists of an energizing ring be-

tween the metal U seal, expand-ing it into the wicker proles ofthe wellhead housing and the casinghanger.Tis 13 seal is a downsized versionof the eld proven 18-3/4 or 16-3/4 metal-to-metal MS-1 seal andts into the reduced annular spacebetween the hanger neck and the

wellhead housing.Extensive FEA analysis was per-formed during the design phase toensure the structural integrity of theseal element and dene reduced set-ting loads to an acceptable range toensure maximum seal performance.

Bridging Seal A bridging seal may be set on topof the primary casing hanger in the

event of a MS-1/ MSE seal failure.It is provided with a similar neckto the casing hanger in order tointerface with the PADPR andthe MS-1/MSE seal element. Telower end provides metal-to-metalsealing against the ID of the casinghanger.

13 Emergency Seal Assem-bly (MSE)Te 13 MSE seal is designed to tinto the same space of the MS-1 sealelement and is used in the event ofdrilling damage to the sealing sur-face in the wellhead housing.

Te seal is provided with a softinlay metal which ows into the

wicker prole lling the originalprole and the score damage. Tis13 emergency seal is based on the

eld proven 18-3/4 or 16-3/4MS-E seals.

13 Wear BushingUsed to protect the sealing areas inthe wellhead housing from damageduring drilling operations.Different to the conventional sys-tem, which uses a resilient lock-down ring, it is provided with ametal locking mechanism to secure

the bushing in the casing hanger.

13 Universal Running Tool(PADPRT)Te single trip pressure assist drillpipe running tool (PADPR ) is ascaled down version of the 18-3/4and 16-3/4 tools with similar fea-tures.Te tool is used to run and cementthe hanger, set and test the MS-1seal assembly. It is designed to per-mit energizing of the seal ring onlyafter it has been positioned in thecorrect location.Due to the reduced diameter and tomaximize the tool capacity, extensiveFEA was performed on all the criti-cal load bearing components.

13 Isolation Test Tool (ITT)Te isolation test tool is a scaleddown version of the 16-3/4 Petro-bras tool.It permits testing of BOP to10,000psi only after it has been po-sitioned correctly in the wellheadhousing. esting can be performed

with or without bore protector orcasing hanger in place.

13 Wear Bushing Running/

Retrieving Tool (WBRRT)ool is designed to install and re-trieve the bore protector and the

wear bushing. Permits testing ofBOP to 10,000 psi.


18/40


13 Seal Retrieval Tool (SRT)Te tool is designed to retrieve theMS-1 or MSE seal element in theevent of leakage.

Prototype Qualification TestProgramTe purpose of this test program

was to conrm that the criteria es-tablished in the design specication

was met in accordance with the ap-plicable standards and specication.Te qualication consisted of integ-rity and functional testing followedby a complete system stack-up.

Vetco Gray leo & Gs Ltdawww.vetco.com

[email protected]: (55) 21 3479 2400

of 32 deg F (0 deg C) using the sametest xture of the pressure test.

Proof Pressure Test:Consist of one pressure cycle to 1.5

times the maximum working pres-sure mainly to prove structural in-tegrity of the seal element. Casing Hanger est Wear Bushing Retrieval est Isolation est ool est (I ) Universal Running ool est(PADPR ) Seal Retrieval ool est (SR ) System Stack-Up est

Slender Drilling System Over-viewTe new 13 Slender Wellhead Sys-tem now allows the entire drillingsystem to be scaled down, reducing

cost, weight and running times.Te Slender Wellhead System de-scribed ts with a 16-3/4 H4 con-nector/ BOP stack and 18-5/8 risersystem, rather than an 18-3/4 BOPstack and 21 riser system.

Work has already been done to de-velop, test and deliver 16 drillingriser systems (Figure 5), which canbe used in conjunction with either16-3/4 BOP stack or 13-5/8 BOPstack to further slim down theoverall Slender Drilling System.

ConclusionsTe results of the successful labo-ratory test program and the partialinstallation of the rst system doesindicate that the Slender Wellheadtechnology is a viable alternative fordrilling in deep water.

The main advantages of thesystem are Permits the use of existing 16-3/4BOP equipment. Allows the use of a smaller diam-eter drilling riser. Reliable metal-to-metal sealing sys-tem based on eld proven technology. Reduced overall well cost. Lower rig costs and use of older rigs.

AcknowledgementTe authors would like to thank Petro-bras for the technical involvement andguidance during the development ofthis Slender Wellhead System.

Metal Seal TestTe rst test was a pressure test todetermine the metal seals ability toreliably seal gas from the top and thebottom. esting from the top wasconducted at eld rated workingpressure of 10,000 psi. Tis test wasto insure the basic sealing criteriaand was conducted in a specicallydesigned test xture.

Temperature TestConsisted of several temperaturecycles with an upper extreme of 250deg F (121 deg. C) and a lower limit

Field InstallationTe rst system consisting of a 30housing and a 16-3/4 x 13 highpressure housing was installed on aproduction well in approximately1400m (4600 ft) of water depth inthe Campos Basin, in the rst quar-ter of 2004.Subsequently, a completion base( ubing Spool) was installed on the

high pressure housing. Te naldrilling phase for the 9-5/8 casingthrough this completion base has yetto be performed.

VETCO GRAY PAID ADVERTISEME


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Te Mexilhao eld is the largest un-developed gas accumulation in theBrazilian Continental Shelf, locatedin Santos Basin, in water depthsranging from 320 to 500 m. Te

eld is situated approximately 137km from the coastline (see Figurebelow) and reserves are estimated tobe 90 billion Sm3 of gas and 6 mil-lion m3 of oil range. Te reservoir isa sandstone and the original pressureis 9,774 psi (67.4 MPa) at 4,656-mof vertical depth.Mexilhaos development is based onthe construction of seven subsea wells(6 horizontals and 1 vertical) con-nected to a subsea manifold that willbe responsible for exporting the pro-duction to a xed platform located in170 m of water depth, at about 20 kmfrom the eld. Te planned start ofthe production is scheduled for 2008,reaching the production peak of 10

million Sm3 of gas per day in 2009.Details of a typical horizontal well inthe Mexilhao eld are presented in agure overleaf.

As Production ow rates of the hori-

zontal wells may be higher than 1million Sm3 of gas per day, drill-ing and production activities on theMexilho eld are likely to encoun-ter considerable safety challenges.

A comprehensive HAZOP, includingrisk assessment, was performed tominimize risk. Most of the practicalimplications of a blowout interven-tion project are addressed, includ-ing intervention strategy, pumpingrequirements, and mud storage. Tepaper also presents details of theblowout rate calculations and relief

well kill requirements. It is worthmentioning that the drilling of a re-lief well would involve high pumpingrates and challenging requirements.

Managing Blowout Risk

Te uncontrolled production ofhydrocarbons from a well, i.e. ablowout, is one of the most seriousaccidents that can happen whileexploring or developing oil and gaselds. It represents a signicant haz-ard to human life, material assets,and the environment. Blowouts arerecognized as one of the main con-tributors to the total risk picture onthe oil and gas offshore industry.

A study of historical data from theGulf of Mexico and the North Seaconrms that, regarding loss of mate-rial assets, blowouts are, indeed, ma-

jor contributors to the total offshorerisk. In general, blowouts are verycostly incidents. Te installations areseverely damaged or totally lost andenormous time losses are typical.Often, wells are plugged, abandonedand reconstructed. Tis data analy-sis also observes that offshore blow-outs cannot be considered majorcontributors to the personnel risks.Other aspects such as occupationalaccidents, helicopter transportation

and vessel stability are consideredmore relevant. Further, concerningthe damage of the environment, thegreat majority of oil that enters thesea is caused by accidents with tank-ers or industrial runoff.More than twenty professionalsfrom ve different companies areengaged in the HAZOP assessmentactivities, comprising the follow-ing tasks: (1) introduction to the

HAZOP methodology; (2) techni-cal review of the proposed plans;(3) review of the main hazardsidentied; and (4) HAZOP of thekey components.

WELL CONTROL

Reducing Risk in theMexilho DevelopmenAntonio C.V.M. Lage, Carlos M. C. Jacinto, Francisco S.B. Martins, Guilherme S. Vanni, OttoL. A. Santos and Jose R. F. Moreiras, Petrobras

The Field of Mexilhao and the Coast of the State of Sao Paulo.


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WELL CONTROL

Technical reviewTe technical review of the proposedplans identies more than a hun-dred operational scenarios, whichare evaluated and prioritized based

on the use of a criticality analysis (2)using a variant of the traditional riskpriority number (RPN) method.Tis covers the probability of eventoccurrence, the severity of the conse-quences and the potential for timelyprior detection of the event.Te identied operational scenariosare classied in accordance withthree levels of criticality that are pre-sented in able I, leading to the fol-lowing result: (1) Level I 37; (2)Level II 70; and (3) Level III 4scenarios.Te scenarios rated level III, whichdeserve special attention in terms ofplanning and execution, are the fol-lowing: (1) geological fault, connect-ing the reservoir to a shallower for-mation, meaning that the reservoiris exposed while drilling the 12-1/4hole section; (2) well control event

while drilling the 8-1/2 pilot hole;(3) well control event while pullingthe string out of the well, and (4)

well control event while performinga formation test.Te level III rated scenarios are sub-mitted to a careful revision in whichfault trees are constructed for iden-tifying minimal cut sets and quan-tifying probabilities. Despite not

being a new method for analyzingcritical events1,3, it is worth to de-scribe briey the main elements ina fault tree. A fault tree is composedof a top event, the and gates, the orgates, the intermediate events andthe basic events. Te combinationof the events in accordance with thetree structure determines whether ornot the top event will occur.

An illustrative example of a fault

tree explains where the well controlevent while performing a forma-tion test. Te fault tree is a logicrepresentation that is not only use-ful for quantifying probabilities

but also for producing a list of pos-sible combinations of events thatcan result in the occurrence of thetop event.

QRA of blowoutsQRAs of blowouts are traditionallybased on historical data4. However,a common problem in QRA is thataccident statistics are too general tobe of signicant value in a specicsituation. Besides that, while dealing

with well control events or kicks, thedifficulties are even more relevant

extension of the Bayesian approachto population variability analysis,

which involves the introduction ofengineering judgment as an addi-tional form of evidence used in the

construction of population variabil-ity distributions. Consequently, aspart of this quantication process,more than twenty experienced engi-neers, who are aware of the opera-tions to be held in the Mexilhao eldand experts in well control issues, aresubmitted to a consultation proce-dure.

because reliable empirical data arerare. One usual procedure consists ofmaking assumptions, which may be

justied by experienced operationalpractice and engineering judgment.

Anyway, in spite of paying special at-tention, the introduction of assump-tions might affect the robustness ofthe results 3.Considering those difficulties, an in-

novative approach5 is introduced tocombine the use of relevant empiri-cal data with expert estimates andquantify the probabilities related tothe basic events. Tis method is an

After constructing the distributionsrelated to the basic events, it is pos-sible to assess the probabilities ofoccurrence associated with the topevents that are representing the levelIII rated scenarios. Subsequently,the probability of occurrence of a

well control event is calculated basedon the fault tree which stands for akick control event while construct-

ing a horizontal well in the Mexil-hao eld. Besides that, reasearch alsohighlights the fact that the forma-tion test scenario is the major con-tributor to a well control incident,

A Typical Mexilhao Horizontal Well.


21/40



22/40


meaning that special care must betaken regarding this operation. Inother words, the probability of a wellcontrol event related to drilling isnegligible compared to performing a

formation test.Further, results show a summary ofthe displacement results at the sealevel. It is worth mentioning that thediameter of the bubble plume at sur-face corresponds to at about 50 m.Besides that, based on the results ofthe research show the best locationfor placing a rig to drill a relief wellis at about 200 m from the wellheadof blowout well in terms of keeping

a safe distance from the structure ofthe bubble plume.

Planning the Kill Operation

Te majority of the well-knownblowout control methods are limitedin terms of working properly in deep

water scenarios. Te best options forkilling a blowout well in deep orultra-deep waters are centered onsubsurface intervention techniques,requiring an effective ow link intothe uncontrolled producer. Howev-er, as it is quite difficult to gain thisstraight access through the blow-ing well, the relief well technique isconsidered the best option for thisparticular scenario15. As a result,the planning activities for construct-ing horizontal wells in the eld ofMexilhao include the design of a re-lief well. Te relief well is plannedto intersect and enter the blowing

wellbore as close as possible to theproducing zone.Besides elaborating a preliminaryplan for the construction of a relief

well, it is necessary to study the hy-draulics aspects associated with thekilling technique involving the dif-ferent well control scenarios previ-

ously identied by the HAZOP.Terefore, the OLGA14 computerprogram is used to calculate thetransient multiphase ow that char-acterizes the killing process.

A complete set of transient multi-phase simulations, involving the levelIII rated scenarios is performed. Temultiphase calculation process startssimulating the blowout, which cor-responds to the period from 0 and 5hours in the graphics. According toFig. 13, the well discharges 445 MMScf/d (12.6 MM Sm3/d) of gas and5,140 bbl/d (817 m3/d) of oil at thebottom of the ocean.From 5 to 16 hours, seawater is

WELL CONTROL

pumped down through the relief well and up the annulus of the blow-ing well with the injection rate of80 bpm, but it is not enough. Teblowing well does not stop the pro-duction, but the reservoir output isreduced.Ten, after this initial killing period,four distinct alternatives are used forstopping the production: (1) injec-tion of 13.5 lbm/gal drilling uidat the rate of 80 bpm; (2) injection

Horizontal view of the numerical grid.

Evolution of the bubble plume.


23/40


of 14.3 lbm/gal drilling uid at therate of 76 bpm; (3) injection of 16.5lbm/gal drilling uid at the rate of72 bpm; and (4) injection of seawa-ter at the rate of 180 bpm. All those

alternatives are effective in terms ofstopping the blowing well.

Conclusions

A practical application of a meth-odology for elaborating a completeanalysis of a blowout is presentedthrough the illustrative example ofMexilhao, which is the largest unde-veloped gas accumulation in Brazil.

A comprehensive HAZOP is carriedout leading to the identication ofhundred and eleven operational sce-narios, which are prioritized basedon the level of criticality, resulting infour scenarios level III rated, whichis the highest one.

A QRA process is performed to eval-uate the risk of a blowout. It showsthat the risk of having a blowout de-parting from a formation test opera-tion is of the order of 3.33 x 10-4,

which is higher than the acceptancecriterion (2.10 x 10-4) dened bythe Health & Safety Executive inGreat Britain.

Te inuence of the sea currents onthe bubble plume leads to the con-clusion that the best location forplacing a rig to drill a relief well isat about 200 m from the wellhead

of the blowing well because it per-mits keeping a safe distance from thebubble plume.Te blowout resulted from a wellcontrol event while drilling, which ischosen based on the philosophy of

worst case scenario, is used for sizingpumping capacity and mud storage.Computational calculations indicatethat the best alternative for killinga blowing well consists of pump-

ing heavy mud. Considering theinjection of a 14.3 lbm/gal drillinguid, 76 bpm of pumping capacityfor a maximum pressure of 5,800psi (40.0 MPa) is necessary for kill-ing the blowing well with the use asingle relief well.

Acknowledgements

Te authors are grateful to Petrobrasand the following people : EnriqueL. Droguett (UFPE - Federal Uni-versity of Pernambuco), Pauli A. A.Garcia (UFRJ - Federal Universityof Rio de Janeiro), and Maurcio M.Neves Junior (UENF State Univer-

sity from the Northern Part of Riode Janeiro).

References

Holand, P.: Offshore Blowouts:Causes and Control, Gulf Publish-ing Company, Houston, exas,USA, 1997.Bowles, J.B. and Bonnell, R. D.:Failure Mode Effects and Critical-ity Analysis: What it is and Howto use it, in opics in Reliabil-ity & Maintainability & Statistics,

Ann. Reliability and Maintainabil-ity Symp., Anaheim, CA, January

1998, 32 p.Ostebo, R., ronstand, L. and Fikse,

.: Risk Analysis of Drilling and Well Operations, paper SPE 21952presented at the 1991 SPE/IADCDrilling Conference, Amsterdam,Te Nederland, 11-14 March.Dervo, H.J. and Blom-Jensen, B.:Comparison of Quantitative Blow-out Risk Assessment Approaches,paper SPE 86706, presented at the2004 SPE International Conferenceon Health, Safety, and Environmentin Oil and Ga Exploration and Pro-duction, Calgary, Canada, 29-31March.Droguett, E.A.L., Groen, F., andMosleh, A.: Te Combined Use ofData and Expert Estimates in Popu-lation Variability Analysis, Reliabil-ity Engineering and System Safety(2004), 83, p. 311-321.

Accident/Incident Data, SPC/ECH/OSD/24, 2004, Health and

Safety Executive, Sheffield, UnitedKingdom.Fannelop, .K. and Sjoen, K.: Hy-drodynamics of Underwater Blow-outs, AIAA paper 80-0219 present-ed at the 1980 Aerospace SciencesMeeting, held in Pasadena, CA, 14-16 January.

opham, D.R.: Te Formation ofGas Hydrates on Bubbles of Hydro-carbon Gases Rising in Sea Water,Chemical Engineering Science, 39,n 5, p. 821-828, 1984

Evolution of the bubble plume continued.


24/40


Milgram, J.H.: Mean Flow inRound Bubble Plumes, Journal ofFluid Mechanics, 133, 1988.

Andrade Jr, P.H., Nakagawa, E.Y.,and Lage, A.C.V.M.: Behavior of

Gas Plumes during an OffshoreBlowout and its Impact on Envi-ronment and Sailing Conditions,paper SPE 38962 presented at the1997 Latin American and Carib-bean Petroleum Engineering Con-ference and Exhibition, Rio de

Janeiro, Brazil, 30 August-3 Sep-tember.Friedl, M.J. and Fannelop, .K.:Bubble Plumes and their Interac-

tion with the Water Surface, Ap-plied Ocean Research, 22, p. 119-128, 2000.

Adams, N, Economides, M., andDaniel, M.: Characterization ofBlowout Behavior in DeepwaterEnvironments, paper SPE 79879presented at the 2003 SPE/IADC

Drilling Conference, Amsterdam,Te Nederland, 19-21 February.Chen, C.L., and Yapa, P.D.: Esti-mating Hydrate Formation and De-composition of Gases Released in aDeepwater Ocean Plume, Journalof Maritime Systems, 45, p. 189-203, 2004.Bendiksen, K.H., Maines, D., Moe,R., and Nuland, S.:Te Dynamic

wo-Fluid Model OLGA: Teory

and Application, SPE Produc-tion Engineering, p. 171-180, May1991.

Noynaert, S.F., and Schubert, J.J.:Modeling Ultra-Deepwater Blow-outs and Dynamic Kills and theResulting Blowout Control BestPractices Recommendations, paper

SPE 92626 presented at the 2005SPE/IADC Drilling Conference, Amsterdam, Te Netherlands, 23-25 February.

SI Metric Conversion Factors

ft x 3.048 E-01 = mgal x 3.785 412 E-03 = m3bbl x 1.589 873 E-01 = m3in x 2.54 E+00 = cm

lbm x 4.535 924 E-01 = kgpsi x 6.894 757 E+00 = kPa

WELL CONTROL

Bottom hole pressure while killing the well.


25/40


Tere are many reasons for drillingextended reach wells. In the caseof the Serra eld, which is located200 km from Natal, in Rio Grandedo Norte, extended reach wells aredrilled because the shallow waterdepths are not good applications

for offshore rigs. Terefore, wellsare drilled from onshore locations toreach offshore reservoirs.

Petrobras Sets Record Casing

Run in Extended Reach WellBy Clovis Neves, Tesco do Brasil and Vicente Abel Costa, Petrobras while running in using 22,000 ft/lbof torque. Tis reduced the axial dragcomponent, resulting in a gain of20,000 lbs hook load which was suffi-cient to allow the casing to reach D.Tis was achieved using the CasingDrive System M (CDS), a tech-

nology developed by esco Corpo-ration. Tis equipment is linked tothe Rigs op-Drive and enables the

SPONSORED BY TESCO

www.tescocorp.com.brContact: (55) 84 3207 3309

Petrobras - (55) 84 3235 3175

Drilling and casing these types of wells is always challenging and thishas led to Petrobras permanentlyseeking new technologies to over-come these challenges.

Well 7-SER-18D-RNS, was drilledby Petrobras using a water based uidand the 9 5/8 casing string was runin to a measured depth of 2,708m.Tis corresponded to a VD of 775mand a horizontal section of 2,113 m.In these conditions, drag forces gen-erated by the casing as it rubs againstthe wellbore are so high that casingcannot be run conventionally.

Simulators used by Petrobras indi-cated that the maximum depth thatcould be reached would be 2,600m.

o overcome the depth limitation,it was necessary to rotate the casing

rig to run casing while rotating orcirculating at any given time. Tisguarantees that casing will be seatedat the planned depth.

o ensure the integrity of casingconnections, escos Multi-Lobe

orque Ring, was placed on theinternal connection of the API But-tress joint. Tis increases the torquehandling capabilities of the connec-tion by a factor up to 4 as comparedto the original capability.Te CDS generated other operation-al benets beyond the ease of runningcasing. During tripping in opera-

tions, the well can be circulated withuid without downtime, because theequipment does not need circulatinghead or extra lines. While cementing,the casing can be rotated to enable

better casing centralization as wellas breaking the gel force and the re-moval of drilling uid which resultsin better cementing job quality.Te benet of casing rotation wasclearly seen in wells 7-SER-17D-RNS and 7-SER-18D-RNS, withthe latter presenting a greater chal-lenge in that the 7 casing was run

and cemented at a measured depthof 3,655 m. Tis corresponded to ahorizontal section of 3,022 m with a

vertical depth of 960 m where casingrotation was a determining factor ina good cement job.Due to these successful rst runs and

within the context of self-sufficiency,Petrobras already plans to set inter-mediate casing strings deeper in theSerra eld while continuing to over-come its challenges in increasing oilproduction in the region.

Figure shows the well plot for 7-SER-18D-RNS - a record casing run for Petrobras.


26/40


Te rising difficulty of nding con-

ventional reservoirs i.e. trapped inuniform structures, containing lightoil, with high permeability, high payzones and easy access, where the un-certainties to its development andassociated risk are not too high, leadsto increasing efforts to turn marginalprospects in economical ones.Current high oil prices as well astechnological advancements are alsoboosting these projects, in which theincreasing complexity in its develop-ment is directly proportional to theincreasing of its uncertainties.In the particular case of offshoreheavy oil scenarios, the difficulty torecover representative uid samples,

due to the high uid viscosities, con-

ducts to unreliable information ofthe PV properties. In addition, thehighly unconsolidated formations,

which are commonly associated withheavy oil, increase the difficulty toobtain representative core samples,leading to non-consistent measure-ments of petrophysical propertieslike absolute and relative permeabil-ity, uid saturations and porosity.

Also, the high oil viscosities together with the high sand content make the well testing operations more com-plicated and consequently poor wellpotential information is obtained. Insuch cases, where the decisions aboutthe entire eld development process

have to be taken under strong condi-tions of uncertainty, a probabilisticanalysis, instead of a deterministic

one, is the natural way to proceed.Based on that, this work aims topresent an application example ofthe Experimental Design and Risk

Analysis techniques to asses the un-certainty of the Net Present Value ina synthetic offshore heavy oil reser-voir during its initial developmentstage.Te reservoir, located under a waterdepth of 1,500 m. and approximate-ly 1,500 m. below the sea bed, re-quires, as any development in theseconditions, a great amount of invest-ment and therefore it is crucial torecognize and analyze each possibleoutcome for the eld developmentin order to map the uncertainties andthe resulting nancial outcomes.Tis work was oriented to assess un-certainty of the Net Present Valueunder different possible values ofvariables related to the reservoircharacterization and productionprocess during the earliest stage ofthe eld development. For this rea-son, only constant values of porosityand permeability through the entirereservoir were considered and not adistribution of them, as it should bedone when a more detailed study isconducted.

Besides porosity and absolute perme-ability, the reservoir area and relativepermeability curves were chosen asuncertain non-controlled variablesrelated to the reservoir characteriza-

Offshore Heavy OilRecoveryJ.W. Vanegas Prada, J.C. Cunha and L.B. Cunha, U of Alberta

HEAVY OIL TECHNIQUES

3D reservoir model.

Uncertainty Assessment Using Experimental Desigand Risk Analysis Techniques


27/40


tion. Production scheme (horizontalor vertical wells) was chosen as theuncertainty related to the produc-tion process and therefore controlledby human decision.

Tis paper describes a methodol-ogy based on the screening study ofuncertain reservoir variables usingthe Experimental Design techniqueto determine which variables andthe interaction between them havethe largest impact in the NPV, andbased on this information establishthe distribution of its uncertainty.Te black-oil reservoir simulatorIMEX1 was used to estimate the

monthly production of oil and waterduring 30 years and then, the NPV

was calculated using some nancialassumptions.

MethodologyExperimental Design is a statisticaltechnique that allows obtaining themaximum information of a givenprocess at a minimum cost. Tismethodology is used to determinethe space variation of the result dueto the variations in the input param-eters of a given process.Te experiment has to be plannedaccording to the nal objective ofthe study; in general there are twotypes of purposes: Screening, where the aim is toknow the input variables that havethe largest impact in the result ofthe process. Most common designsto attend this purpose are two levelsfull and fractional designs3,4. Levelsare the values that each variable orfactor can take when the experimentis being run. Modeling, where the aim is toconstruct a statistical model of theprocess. In this case the experimentis done using more than two levels,in order to capture the most prob-

able variation of the result due to thevariation of the input parameters.In this study the process is a owsimulation run whose result is usedto calculate the NPV based on some

nancial assumptions. Te time cho-sen for the project was 30 years andthe cumulative production for eachmonth during this time was simu-lated. Te input parameters are theuncertain variables chosen for thiscase. Te choice of the input param-eters and its range of variation is themost important stage in the uncer-tainty analysis.

Reservoir model and uncer-tain variablesTe analysis was done on a reservoirmodel covering an area of approxi-mately 123.5 km2, with a maximumthickness of 100 m and anticline ge-ometry. Te gure on page 26 showsa 3-D image of the reservoir.Te production scenario is offshore

with 1,500 m of water depth and2,970 m. to the reservoir top. Teproduction mechanism simulated

was waterooding.Te reservoir was modeled using a55x45x4 grid, 9,900 blocks in total,and the average run time to simulate30 years of production was 4 min-

utes in a Pentium IV PC.Te produced uid was an oil of 13API and viscosity of 152 cp at sur-face conditions. Te initial reservoirpressure was 314 kgf/cm2 at 3003

m. and the reservoir temperature was 70 C. A water oil contact waslocated at 3,140 m. depth.Te reservoir characterization vari-ables, which are non-controlledvariables, chosen to have a large un-certainty are: permeability, relativepermeability curves, porosity andarea of accumulation. Te range ofvariation for absolute permeability,porosity and area were based on pes-simistic, expected and optimisticvalues.Te reservoir area uncertainty is rep-resented by three different maps.Te uncertainty in the reservoir areais justied by uncertainty associated

with the seismic interpretation in which the precision to infer the res-ervoir thickness directly affects thearea of the accumulation.

Analysis shows the differences oforiginal oil in-place for all possibleareas as well as the number of activeblocks used during the simulations.Te values of parameters used to cre-ate the 16 different tables of relativepermeability curves can be found in

the original paper.16 different cases of the Corey mod-el were used to construct the respec-tive equiprobable tables of relativepermeability curves.

Optimistic area.


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Te uncertainty in the productionscheme was dened using either ver-tical wells or horizontal wells. Sincethe productivity index (PI) of hori-zontal wells is a source of uncertain-

ty it was decided to consider threepossible cases for the productivityindex of horizontal wells. Researchshows the different possibilities usedto map the uncertainty of the pro-duction scheme.Te number of wells and their loca-tions were optimized for each pos-sible reservoir area considering ver-tical and horizontal wells type ofexploitation schemes. Tus, each

area would be developed in the bestpossible way using vertical wells as

well as horizontal wells.

In summary, there are 5 parameters with large uncertainty, 3 levels ofporosity, 3 levels of absolute perme-ability, 16 tables of relative permea-bility, 3 different reservoir areas and

4 production schemes. Tis givesa total of 1,728 possible combina-tions.

Net Present Value (NPV)CalculationNPV was selected as the nancialcriterion for the economical analy-sis. Tis analysis was done based onthe results of the simulation runs.Each case was run to simulate a pe-

riod of 30 years and the result of themonthly cumulative production ofoil and water was the base to calcu-late the monthly net income.Some nancial assumptions weremade in order to determine theNPV: All investments are done at thepresent; Cost of drilling and completion ofa horizontal well is US$ 15 MM; Cost of drilling and completion ofa vertical well is US$ 10 MM; Cost of surface facilities is US$500 MM plus US$ 5 MM per wellfor sub sea equipment; Cost of production is US$ 8 perbarrel of produced oil; Cost of water injection and treat-ment is US$ 1.5 per barrel of pro-duced water; Te interest rate for investments is12% nominal per year; Oil price is US$ 25 per barrel; axes represent 42% of the grossincome; axes begin to be paid only afterthe return of the investment; Before the breakeven the income isdiscounted to an interest rate of 6%per year.

Screening AnalysisTe initial objective is to do a screen-ing analysis to dene which uncer-tain variables have a larger impact onthe NPV.

Tis analysis was done using a fullfactorial experiment design at twolevels. In this design, two values ofeach parameter are selected and amatrix containing all possible com-

binations of them is constructed,then the simulator is run using eachcombination. Te values are se-lected to represent the entire rangeof variability of each parameter, inother words, the two extreme val-ues of each uncertain variable arechosen. It is a common practice inexperimental design to normalizethe parameters to values -1 and 1,assigning -1 to the minimum and

1 to the maximum of the same pa-rameter.In this work the number of runs isgiven by 25, or 32 different cases arerun to dene the effect of each fac-tor and the effects of the interactionsbetween them on the Net PresentValue. Research shows the matrix ofruns used to perform the screeninganalysis. Te values were assigned to1 and -1 for each parameter.In order to run and calculate theNPV for all combinations a programto manage the input/output les ofthe simulator was written. Tis pro-gram builds the matrix of runs, thenfor each row of the matrix or combi-nation of the uncertain variables itopens and changes the keyword val-ues in the simulator input le. Fol-lowing, the program calls the black-oil commercial simulator and runsit using the input le. When thesimulation is nished the programopens the simulator output le andcollects the cumulative productionof oil and water for each month.Finally, using the previous nancialassumptions the program calculatesthe NPV. Te NPV results for thescreening analysis were presentedtogether with the codied variables

used in the simulations.In order to determine the effects ofeach variable and the effects of thecombination of variables on theNPV, it is necessary to construct the


In the vertical well type of exploi-tation, all injector and producer

wells are completed in each one ofthe four layers, while in horizontal

wells, the injectors are placed at thebottom of structure (layer 4) andthe producers at the top of it (layer1). Te assumed average horizontal

well completion length was 500m.Research shows the number of injec-tor and vertical wells used to simu-

late 30 years of production for eachreservoir area. Te gure on page 27shows as an example a 3-D map ofthe optimistic area and a horizontal

well exploitation scheme.

The assessmentof the Net PresentValue uncertain-ties for an offshoreheavy oil reservoirin its earliest stageof development wasdone by means ofexperimental designand risk analysistechniques.


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so called matrix of contrast coeffi-cients. Tis matrix is built by mul-tiplying element by element the col-umns of the matrix of runs, in orderto obtain new columns correspond-

ing to the interactions between thevariables4. Ten, a column of ones isadded at the rst column. Tis col-umn (M) is used to determine themean of the NPV results. Researchshows the matrix of contrast coeffi-cients, where columns 1, 2, 3, 4 and5 are related to the codied inputvariables: porosity, absolute perme-ability, relative permeability, area,and production scheme, respective-

ly. Te other columns are related tothe interaction between the variablesand the codes are determined bymultiplying element by element therespective columns. For example,the column 123 is related to the in-teraction between porosity/perme-ability/relative permeability and thecodes are found by the element-by-element multiplication of column 1,2 and 3.Te remaining terms of D dividedby 2n-1 correspond to the vector ofeffects. In this case n=5 and the vec-tor of effects is shown in able 10.

As an example, we can see in thistable that the effect of increasingthe porosity from 0.24 to 0.32 is,in average, US$171 MM in termsof NPV. In this table also is shownthe effect caused by the interactionbetween variables, for example theeffect of increasing the area andchange the production scheme fromvertical wells to horizontal well good PI is in average US$158MM.It is important to note that by do-ing a full factorial design it is possi-ble to determine all possible effectson NPV, i.e. 5 effects of rst order,10 of second order, 10 of third or-

der, 5 of fourth order and 1 of fthorder.In order to dene which effects arereally important it is necessary toconstruct a Pareto plot with a sig-

nicance level of 95%. It means thatonly the effects, whose values aregreater than the value correspondingto 5% of cumulative probability, arestatistically important.In the Pareto plot, where the valuefor P5 (ve percentile) is US$ 29.32MM. It is noticeable that the mostimportant effects over the NPV, indecreasing order, are:1. Permeability;2. Production scheme;3. Area;4. Relative permeability;5. Interaction Permeability -Relativepermeability;6. Interaction Permeability - Pro-duction scheme;7. Interaction Permeability Area;8. Porosity;9. Interaction Area Productionscheme;10. Interaction Relative permeabil-ity Area;11. Interaction Porosity Perme-ability;12. Interaction Permeability - Rela-tive permeability Area;

13. Interaction Porosity Area;14. Interaction Permeability Area Production scheme;15. Interaction Porosity Produc-tion scheme.

he previous result leads to theconclusion that, in this case, allthe variables taken into consid-eration cause an important effectover the projects NPV; thereforethey should be included when theoverall uncertainty of the projectis determined.Following this premise, the next sec-tion illustrates an alternative to con-struct the uncertainty distribution ofNPV for this project.

Uncertainty AnalysisTe uncertainty analysis aims todetermine the Expected MonetaryValue (EMV) for the developmentproject. wo cases are considered; inthe rst, there is some informationabout probabilities of the uncertainvariables and in the second there isno information about any probabil-ity.For the rst case, probabilities as-sociated to the values of porosity,

were calculated along with absolutepermeability and area. For the rela-tive permeability and production

scheme, it is assumed each outcomebeing equiprobable. A decision tree was constructed usingthis information. It can be seen thatthe total of all outcomes for the NPV

Pessimistic area.


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is given by 3x4x16x3x3 = 1,728. Us-ing the previously explained programall the 1,728 cases were run and theNPV value was found for every pos-sible outcome. Te total simulationtime was around 5 days in a PentiumIV PC.Ten, the Expected Monetary Value(EMV) was calculated assuming in-dependence between the events ofeach variable. For example, the prob-ability that the porosity assumes thevalue of 0.2 is not affected by anyvalue that other variable can assume,in this case permeability, relativepermeability, area, or productionscheme.For the second case, the assump-tion of no information about prob-abilities was used in the uncertaintyanalysis.Considering that the values of eachvariable cover the entire range ofvariability, a histogram of the1,728 possible results can give anidea of the NPV uncertainty dis-tribution.

A histogram with 25 bins was cre-ated where the Expected MonetaryValue was found by assuming therelative frequency as the probabilityof occurrence of the given value at

the interval center of its respectivebin. Te EMV calculated using theassumption of no information aboutprobabilities is $US 914 MM. Tisvalue conrms the one found in thecase when some information aboutprobabilities is assumed.It is important to notice that theEMV in the rst case depends onthe probability values that the pa-rameters can assume, but it is im-portant to notice that for differentvalues of probability tested the EMV

was close to $US 914 MM.Illustrating this is the cumulativeprobability distribution curve ofNPV for this project. Some usefulpoints in this curve are P10 = US$302 MM, P50 = US$ 754 MM, andP90 = US$ 1,560 MM.From the previous analysis we canconclude that under the consideredassumptions this project is highlyprotable.

ConclusionsTe assessment of the Net Present

Value uncertainties for an offshoreheavy oil reservoir in its earliest stageof development was done by meansof experimental design and risk anal-ysis techniques.

A screening analysis was performedto conrm that the chosen uncer-tain parameters caused a great im-pact into the NPV of the project.Tis analysis was done using a two

level full factorial experimental de-sign. A program was written in order touse a commercial black-oil simula-tor for the uncertainty assessment ofthe Net Present Value through varia-tions of some petrophysical and/orproduction parameters.Te uncertainty analysis was done,rst assuming some informationabout probabilities of the uncertain

parameters, and then assuming thatthere is no information about it. Inboth cases the result of the Expect-ed Monetary Values was $US 914MM.Considering the schemes as mutu-ally exclusive events, the horizontal

wells would be the best choice forthe development of this reservoir.One step forward in the eld devel-opment study would be the imple-mentation of a Monte Carlo meth-odology to better assess the NPVuncertainty, sampling the completeprobability distribution for the un-certain parameters instead of simplyassigning discrete values of probabil-ity for them.

Nomenclature A = Area, m2EMV = Expected Monetary Value,$USKrw = Water Relative permeability K = Absolute permeability, mDnw = Coefficient of Corey model for

water relative permeabiliy no = Coefficient of Corey model foroil relative permeabiliy NPV = Net Present ValueP = Probability P.Sch. = Production scheme

Sor = Residual oil saturationSw = Water saturationSwi = Initial water saturationf = Porosity


Horizontal well production scheme.


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It is fashionable these days to use thedeepwater label to distinguish a par-ticular type of drilling. But is this sodifferent to shelf or onshore practices?Te common denominator of alldrilling activities is the managementof people, technology and locations.Customs, environmental, and legal

issues exist also. And so does that de-tail of prospect selection. Tats ne.But this logistical labyrinth is essen-tially the same whether youre sittingin a company mans office offshore

Angola or onshore Azerbaijan.echnology isnt exclusive to deepwa-

ter either. Smart completions usingbre optics and satellite communi-cations are enabling the productionof onshore production zones to becommingled and controlled. Acidi-cation through water injection linespermits live well intervention with-out skidding land rigs. New gravelpacking and ltering techniques canbe used to control sand productionin shelf elds. In fact, it seems anequally compelling case can be madefor technology to be used in onshoreor shelf locations to improve mar-ginal economics as can be made fordeepwater operations.

What really differentiates and im-pacts deepwater activities are thechallenges associated with incrediblesea depths. Of course, block size indeepwater frontier areas such as Brazilcan reach huge proportions; 25,000sq km (thats 1,000 GOM blocks).Tis makes picking and drillingprospects tough, irrespective of op-

erator resources or experience. But itis greater water depth that leads tohigher pressures and overburden andthats where the problems arise. Tedrilling engineer has to consider and

overcome bottom hole pressures thatcan exceed 22,000 psi and mudlinetemperatures that can fall as low as35 degrees F.So where is the deepwater line drawn?

According to Petrobras, waters be-tween 1000-2000 m depth are clas-sied as deep. Beyond this are the

ultra deep waters (this line goes to3500m for the present). Deepwaterdenitions aside, deeper seas meandeeper pockets.Deepwaters are characterised bystrong currents which create a needfor high specication rigs that arecapable of maintaining station andin some instances of suppressing

Vortex Induced Vibration (VIV).Such rigs are expensive. Contract-ing one in the GOM can cost a cool$400,000 per day. Deepwaters arealso characterised by young depo-sitional formations that differ fromshelf and onshore scenarios. Exem-plifying this is the typically narrow

window between pore pressures andfracture gradient (ppfg). Low frac-

ture gradients can necessitate lighterdrilling uids and lighter cementslurry. While rising pore pressurescan often upset the delicate fracturegradient destabilising the well-boreand jeopardising the section, if notthe entire well.

A consequence of narrow PPFGis the need for close tolerance

Deepwater FeatureBy W. Rasheed

DEEPWATER WELL CONSTRUCTION

PPFG Example.


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and contingency casing schemes.(Accompanied by a need for con-centric underreaming. Its easier toset casing with gauge hole). A po-tential consequence of a tight ppfgis the requirement of contingencycasing strings to isolate formations.In short, deepwater Operators musthave an excellent knowledge of well-bore stability to avoid a formationinux (kick) or fracture the shoe

which would result in losses. New well construction methods are beingdeveloped for just such an eventual-ity. Tese include the dual gradientsystem. Petrobras is presently spon-soring a JIP that develops a subseapump to control the pressure at the

wellhead and studying gas injectionsystems. For this technology to work,risers must be resistant to collapseforces as soon as gas is injected intotheir bases.Further engineering challenges areadded by temperature gradients. Anegative gradient runs from surfaceto seaoor but this turns positive be-low the mud line. Equations becomemore complicated as cooler surfacemud alters the temperature proleas it pumped downhole. While gashydrate formation is a common

problem that is difficult to resolve.Hydrates trap natural gas inside wa-ter molecules and bond with metal.Tis can result in tubing blockagesand affect valve and BOP operation.

Unfortunately, deepwater environ-ments present the ideal combinationof low temperatures, high seabedpressures, gas and water that causehydrate formation. Extensive mod-eling is required to minimize hy-drate formation. Low temperaturesalter the properties of cement whichmean new designs of cement slurriescomposition are required. Existing

API norms do not cover low deepwater temperatures and stringenttest procedures are now determiningthe properties of cement slurries indeep water operating conditions.Riser manipulation is another chal-lenge is found in ultra deep waters- 2000m and beyond. Research isbeing carried out on innovative light-

weight risers. By reducing the weightof the risers and their joints, it shouldbe possible to use lower cost t-for-purpose rigs in ultra deep water. Aparallel technology that has been de-veloped is the Slender Well conceptto permit the use of smaller diameter

wellbores and lighter risers. A further innovation has been thetorpedo pile, which is a torpedoshaped anchor that is dropped froma certain height to the seaoor. Teresulting kinetic energy is sufficient

to drive the pile 20 to 30 m downinto the oor, providing the re-quired vertical-load resistance. Tetorpedo subsea well base was devel-oped based on the same concept. It

DEEPWATER WELL CONSTRUCTION

penetrates into the soil because of itsown weight and then, if necessary, ishammered down to the nal posi-tion. It is a new product and morethan six torpedo well bases havebeen successfully deployed so far. Itis possible cut drilling time by a dayor two, per well, just by using thistechnology. Considering current rigrates, it represents a signicant econ-omy.Undoubtedly, deeper waters addgreater cost and complexity to op-erations. But expenses can be cut inthree ways. Firstly, by simplifying welldesign. Well trajectories should notonly be compared in terms of how ef-fectively targets are reached, but alsoon their overall cost effectiveness.Secondly, by reducing casing strings.Casing can be set deeper, based onreal-time pore pressure and fracturegradient detection. Accurate predic-tion will reduce contingency casing.Offset data can help to rene porepressure models and enhanced porepressure detection will make the bestof the casing program while drilling.Modeling steady and dynamic stateuid behavior will reduce surprises.Last but not least, costs can be cut bycontracting t-for-purpose technol-

ogy, especially rigs.Editors Note: Would like to thank JoaoCarlos Placido and Antonio Lage ofPetrobras CENPES.

Deepwater rig in the Campos Basin.


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Subsea Equipment,Risers & PipelinesPetrobrass long history of develop-ing subsea completions shows howthe company has constantly metnew challenges when designingand deploying subsea productionsystems. A key foundation of the

development strategy has been thegeneration of new technology waysand means in order to meet new ap-plication scenarios and keep costsfrom spiraling. Te Subsea equip-ment, riser and pipeline project willenable E & P in water depths ex-ceeding 3,000m.

Te project is focusing on the fol-lowing items: Subsea connection system for3,000m water depth; Completion riser for 3,000m waterdepth; Guide lined installation proceduresfor 3,000m water depth.

Unconventional subsea pro-duction systemsLooking beyond conventional wis-dom is the vision behind this proj-ect. Te idea is to evaluate uncon-ventional technologies accordingto their cost effectiveness when ap-plied to the needs of deepwater, ul-tra-deepwater and marginal elds.Tese evaluations will also identifynew technological developments tobe launched and make concreterecommendations regarding theirtechnical and economical feasibility

based on the needs of different elds.Promising technologies will then bedeveloped as separate sub-projects.Te technologies being consideredare:

Subsea water disposal All-in-one wet Christmas tree

Steel catenary riser sys-tems for ultra-deepwater

Risers, owlines and multifunctionalumbilical cables are undoubtedly themost critical components of typicaloating production systems in ultradeep waters.

Te use of rigid owlines or pipe-in-pipe and steel, composite, or hy-brid catenary risers (SCR, CCR &HCR) are important options forthe transportation of uids in ultra-deepwater conditions. Te SCR can

be cost-effective and as yet is alsothe only eld proven technical solu-tion for large diameter hydrocarbonpipeline ows, especially from semi-submersibles or in ultra-deepwaters,

when compared with traditionalexible risers. Teir use in conjunc-tion with FPSOs was the subject ofa comprehensive study conductedby Petrobras and completed in late1999; however, a prototype has notyet been installed.Results from the monitoring systeminstalled in the P-18 SCR (the worldsrst prototype of a SCR) have beensystematically used to compare andcalibrate Petrobrass SCR computermodels. Presently, such models arebeing ne-tuned to enable the de-sign of SCRs for Roncador and Mar-lim Suls module 4. Te lazy-waveconguration for SCRs is

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Brazil OG Issue 2