youngpetro - 13th issue - autumn 2014

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Call for PapersYoungPetro is waiting for your paper!

� e topics of the papers should refer to: Drilling Engineering, Reservoir Engineering, Fuels and Energy, Geology and Geophysics, Environmental Protection, Management and Economics

Papers should be sent to papers @ youngpetro.org

For more information visit youngpetro.org/papers

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SUMMER / 2013

ISSN 2300-1259

WINTER/SPRING / 2012

ISSN 2300-1259

AUTUMN / 2012

International Student Petroleum Congress & Career Expo6th Edition, 22nd - 24th IV 2015

Krakow, AGH UST

AUTUMN / 2014

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3 3 Editor’s Letter 3

Climbing to the top demands strength, whether it is to the top of Mount Everest or to the top of your career.

— A. P. J. Abdul Kalam

Dear Friends,I am honoured to hand to you the newest issue of YoungPetro Magazine prepared by a totally new Editorial Board. What makes me even more proud is the theme of this issue. You will find here a por-tion of texts about career. I am fully aware of the meaning of the topic for every student, who would like to develop their skills during university stud-ies and find a dream job after graduating.

Nowadays, every young person has to do their best to be prepared to survive on a job market. We try to enhance our competencies by choosing the best course, taking extra classes, learning foreign languages and participating in numerous train-ings. However, most importantly, we like to rely on the opinions and experiences of our older col-leagues, who made their first steps in professional career only a few years ago.

Their advice has the biggest value for us, as these people know which steps to take, which mistakes we should avoid and what is the most important thing while beginning the career. Because of that Maciej Wawrzkowicz and Patryk Szarek prepared an article “Two Worlds – One Industry. From Student to Professional,” in which you will see the graduates’ point of view: what they dreamed

of, how they saw their future job during university studies and what the reality looks like now.

We cannot forget about professional experience that we can gain during studies thanks to intern-ships being offered by many companies. In this issue our Editors share with you their experiences acquired during summer internships.

I hope that you will find many interesting and use-ful tips in both articles and that they will help you to find some new inspirations on your way to find-ing a dream job. Apart from the texts connected with career, traditionally, you can find here a por-tion of noteworthy research articles, as well as our constant columns: On Stream and How It Works. Do not miss the coverage of WPC 2014, one of the biggest industry conference, which was organized in June in Moscow.

I hope that you will find the issue interesting and that it will be a source of positive inspiration for your studies and for your future work. Do not for-get to send us feedback, let us know about your impressions after the reading!

Enjoy YoungPetro during long autumn evenings!

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Editor-in-ChiefJoanna [email protected]

Deputy Editor-in-ChiefMaciej [email protected]

ArtMarek Nogiećwww.nogiec.org

EditorsRadosław BudzowskiAgata GruszczakAlina MalinowskaPaweł ParyłaEdyta Stopyra

Science AdvisorEwa KnapikTomasz Włodek

Proof-readersPaweł GąsiorowskiAleksandra Piotrowska

ITMichał Solarz

LogisticsPatryk Szarek

MarketingBarbara PachAneta Maruszak

AmbassadorsAlexander Scherff – GermanyTarun Agarwal – IndiaMostafa Ahmed – EgyptJin Ali – RussiaManjesh Banawara – CanadaRakip Belishaku – AlbaniaCamilo Andres Guerrero – ColombiaMoshin Khan – TurkeyAhmed Bilal Choudhry – PakistanMuhammad Taimur Ashfaq – PakistanViorica Sîrghii – RomaniaMichail Niarchos – GreeceRohit Pal – UPES, IndiaUsman Syed Aslam – India

PublisherFundacja Wiertnictwo - Nafta - Gaz, Nauka i TradycjeAl. Adama Mickiewicza 30/A430 - 059 Kraków, Polandwww.nafta.agh.edu.pl

issn 2300-1259

Published by

An O�cial Publication of The Society of Petroleum Engineers Student ChapterP o l a n d • www.spe.net.pl

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Two Worlds – One Industry. From Student to ProfessionalPatryk Szarek, Maciej Wawrzkowicz

Student Internship – Way of Spending the Summer!Aneta Maruszak, Barbara Pach, Piotr Chojnowski

Combined Drill Bit with Selected Variable StepVasyl Movchan

Smart Way of Mitigating Drilling Problems. Review of UBD vs. MPD

Mian Tauseef Raza

Effect of Mobility of Oil in the Performance of Process Steam Assisted Gravity Drainage

Astrid Xiomara Rodriguez

Responsibly Energising a Growing WorldJoanna Wilaszek

How it works?Maciej Wawrzkowicz

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Find us on Facebookfacebook.com/YoungPetro

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For online version of the magazine and news visit us at youngpetro.org

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On Stream – Latest News

Radosław Budzowski

Japan will start importing gas from the US in 2016

Chubu Electric Power and Kansai Electric are planning to start importing LNG from the United States in 2016. Both companies are aiming to make this plans come true because it is cheaper up to 1/3 than importing liquefied natural gas from the Middle East. Contract between Chubu Electric Power and the company Cheniere En-ergy provides Japanese company the supply of 700 thou-sand tons of liquefied natural gas, in the period from July 2016 to January 2018. Deliveries will commence from the Sabine Pass, Texas terminal in the United States. Installation for the liquefaction and transportation of LNG should be ready by the end of 2015. The size of the contracted amount of gas that will being sent to the two Japanese companies will cover 3–5% annual demand.

US overtakes Saudi Arabia and Russia in oil

production

According to the published estimates, the United States will be the largest oil producer in the world this year. Thus is going to overtake the current leaders – Russia and Saudi Arabia. A significant increase in oil production United States owes the growing shale oil extraction. Dur-ing the first quarter of this year, crude oil production in the United States amounted more than 11 million barrels of oil per day. At the same time, Russia achieved approx-imately 10.5 million barrels, and Saudi Arabia: 9.45 mil-lion barrels. The International Energy Agency estimates that by 2019, the production of crude oil in the United States will rise to 13.1 million barrels per day. Volume pro-duction at this level will be continued until 2030. After this time, there will be a slow decline in the size of the exploited resource.

Kurdistan grows on oil sales, in the background the

Iraqi conflict

Petroleum resources of Kurdistan, although they are smaller than in other parts of Iraq, have a strategic im-portance for the relations between Kurds and Baghdad, as well as for the potential gas export to Turkey and European Union countries. This autonomous region ruled by president Masoud Barzani, for several years has been gradually gaining more independence from the Iraq Government. Robin Mills, the head of consulting Manaar Energy Group that provides advisory services for O&G industry, said that the Kurds have used ISIL offensive to take over most of the territories, including the city of Kirkuk and oil fields in the surrounding area. From both oil fields – Kirkuk and Bai Hassan – they can export even 450 thousand barrels per day but since March this year, Kurds haven’t mined significant quan-tities after damaging Iraqi-Turkish pipeline Kirkuk-Cey-han pipeline by saboteurs. Current export is a big step forward for the Kurds towards even more independ-ence. In 2011, the government of Kurdistan signed an independently contract with Exxon Mobil and has started mining in the north of the country. Since then, the Kurds have signed new contracts – with Chevron, Gazprom and Total.

Kurdish Regional Government is planning to produce up to one million barrels per day in the future. Deposits of oil in the region is estimated at 45 billion barrels. On the basis of the Iraqi constitution adopted in 2005, crude oil – the main wealth of the country – should be passed by all the provinces to the central government, and only government has the right to export it. The Kurds, howev-er, do not apply to this provision.

Patryk Szarek, Maciej Wawrzkowicz 9

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å Two Worlds – One Industry.

From Student to Professional

Patryk Szarek, Maciej Wawrzkowicz

Expectations vs. Reality�The moment we become students of the uni-versity, we feel that we can achieve everything we dream of and that nothing will stand in our way – in short, we are convinced that the world is our oyster.

Unfortunately, the initial euphoria does not last long and it is already in the course of our studies that we become aware that the way leading to suc-cess is not a bed of roses.

It turns out that our future profession requires not only thorough education and experience, but also – above all – knowledge of specialist English used by the representatives of this particular field of study and in the oil industry.

Theoretical rudiments are to be acquired in the course of our studies, the language is to be per-fected on our own, but it is the gained experience, that is going to decide about our value as potential employees on the job market.

We asked a group of recent graduates about their expectations towards their future job. "During the studies I have been thinking that the job will be challenging, satisfying and profitable," – David ad-mits – "so far I am not disappointed." On the other hand, John, who has graduated from the Univer-sity two years ago, told us: "What astonished me most was the fact, that job conditions turned out far worse than I had expected during the studies. What is more, I had never been thinking about potential hazards and demanding character of this profession."

Employees’ Age in the Industry�Employees’ age diversification in Oil & Gas in-dustry is relatively high. Staff are mainly people in the prime of life, both women and men. Generally, the number of working women in the industry is disproportionately low in relation to the number of employed men.

When comparing different continents, the best situation is in North and South America, where the number of employed women in Oil & Gas in-dustry accounts for more than 10% of all employ-ees. The lowest percentage of working women may be noticed in the Middle East and it is just 3.1%. The largest occupational group consists of people aged 30–34 years, 16.2% of men and 22.9% of wom-en employed in the industry. Considering work experience in terms of years, the largest percent-age of 28.3% is constituted by employees working less than 4 years. Other groups (5–9, 10–19 and over 20 years of work) followed at a comparable level of approx. 24%.

Where Can I Earn the Most?�Despite their interests or passions, many stu-dents choose their future specialization basing on potential financial profit. Of course, this way of acting isn’t the best option. Every student should remember that the amount of money we earn depends mainly on our work experience, not on the sort of diploma we are possessors of. "At first I expected a good training and smooth transition

10 Two Worlds – One Industry

from being a student into being a professional. It was my first job, so it was very important for me to be shown "how it all works" and to be given me some experience and opportunity for develop-ment. And I think I got it," says Aga. It is easy to notice that earnings of a graduate in comparison to a more experienced worker vary considerably, which may indicate how important an intensive training at the beginning of the first job is.

According to Hays Salary Guide, the best salaries are obtained by students who graduated from geosciences and petroleum engineering field of study. They may earn as much as $45,000 annual-ly. Satisfied with their first remuneration will also

be subsea and project control graduate engineers with annual salaries above $40,000. What is worth mentioning is the fact that salaries of senior engi-neers are sometimes 2 times higher (take a look – "Drilling") than those of graduate engineers. This is why a fresh graduate employee should be focused mostly on training and not on salary.

Office vs. Field�Petroleum industry does not mean only huge constructions, rigs, pipes, refinery systems or smell of crude oil or bitumen. Did you happen to think about working in the office? What kind of abilities

0 20 40 60 80 100

Female [%]Male [%]

Africa

Asia

Australasia

Europe

Middle East

North America

Russia and CIS

South America 88.7% 11.3%

86.8% 13.2%

81.6% 18.4%

95.8% 4.2%

89.2% 10.8%

89.3% 10.7%

92.7% 7.3%

91.6% 8.4%

�Fig. 1 – Regional gender differences


autumn / 2014

should you possess to manage it easily? According to Pawel Wodka, a specialist at Fair Recruitment company, to main skills necessary in Oil & Gas office belong: good knowledge of math/physics/science, understanding of engineering principles, ability to solve complex scientific problems and to work with sophisticated computer programs for data analysis. One of the main characteristics of such jobs is constant development of profession-al skills, which is reflected in a large number of

different trainings and courses. Due to a relative-ly high cost of specialist trainings, office workers should see it as one of the most important bene-fits, which compensate lower salaries than those of rig workers. However, they are still attractive in relation to other industries and are supported by different benefits. On the other hand, there is field work. Working in the field usually means frequent rotation. Rigs are located in the places where re-sources are available, which often means places

Female [%]Male [%]

<24

25–29

30–34

35–39

40–44

45–49

50–54

55–59

60–64

>652.0%

0.3%

4.7%2.1%

7.8%4.9%

10.1%8.6%

11.4%8.5%

13.7%11.5%

14.4%15.5%

17.6%22.7%

13.7%19.1%

4.5%6.6%

�Fig. 2 – Age of employees

12 Two Worlds – One Industry

far away from civilization and very possibly with harsh weather conditions. It might seem adven-turous to some extent. "Working on a rig means everyday routine described by shifts and enforced by HSE rules," says Wodka. "Unlike some TV doc-umentaries show, rig work can be boring. But still you should expect the unexpected as the working environment is by definition hazardous. So, rather than adventure seekers, companies are looking for mature, responsible people with strong charac-ter and safety awareness," he says. What attracts people to work on a rig then? For sure, one of the most important advantages is earnings, which are among the highest within industry. Moreover, even entry level vacancies are often paid more than the average, even when compared to non-oil and gas industry. Well, have you made your deci-sion yet?

Working Home and Abroad�Did you know that more than 50% of employ-ees in Oil & Gas industry work abroad? According to Hays data, almost the same percentage stayed in their country. What affected those who decided to move to other country? The decision was often

not made by themselves. "My company required me to change my work place due to the growing workforce demand in Africa region," Michael told us. "Actually, I had no choice, I had to move. But, to be honest, so far I do not complain about it." On the other hand, the decision is more often made because of the salary. In regions of the biggest pe-troleum and gas production, it can be even several times higher, especially when experienced profes-sionals are taken into account.

HOME ABROAD52.6% 47.4%

�Fig. 3 – Working at home or abroad

Annual Salaries by Discipline Area

Operator, Technician Graduate Intermediate Senior

Drilling 65 200 37 000 67 900 86 900

Geoscience 60 000 45 000 56 000 95 400

Piping 47 000 34 000 43 000 59 900

Production Managment 55 800 32 400 52 100 79 600

Project Controls 55 000 40 000 50 600 72 600

Reservoir, Petroleum Engineering

45 900 44 800 67 800 105 700

Subsea, Pipelines 54 200 41 400 62 400 89 100

�Table 1 – Salary information ($)


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How to Get a Dream Job?�This question is popular or even the most pop-ular among young, ambitious students. And no wonder – everyone would like to know a recipe for success that could be taken for granted. The only problem is that there is no such formula. "Everything depends on our motivation, involve-ment and sometimes even cleverness and more often luck.

Nevertheless, there are some verified actions and ideas, thanks to which we may be far closer to our dream job after graduation. Get involved in as many projects, societies, organizations and train-ings as you can," clarifies Aga. "It will help you to develop your interpersonal skills, work with peo-ple, get to know them and develop as the person," she says. According to Muhammad from Pakistan, the style of our performances plays a very im-portant role. "Always work on 'three Cs', which means: Concepts, Confidence and Communica-tion. You will definitely rock", he admits. What about knowledge? Not every university provides us with sufficient knowledge of technology and industry. Thus, as a fresh graduate we don’t know many things. However, "(…) technical knowledge from the university is not the most important one, it is the attitude and the ability to constantly learn and develop," Caroline says.

Summary�We asked our respondents about choosing their path of career once again. What is interesting, no-body gave a negative answer. Dream job is not only an abstractive term we may sometimes think about. The most significant thing is to stick to our plan and remember that academic knowledge is not everything. It is strongly advisable to consid-er what predispositions we have. Do you want to work in a field or in the office? In your country or rather abroad? As a driller or reservoir engineer? And what is the most important, will you be satis-fied with a job of this kind? Knowledge of what we exactly want will be for sure very helpful. Further-more, it will provide us with a personalized goal that we will be trying to achieve and will enable us to present ourselves during a job interview as a self confident candidate that knows what his or her dream path of career is. By realizing what your personal aim is, you will reach it and evolve very quickly from a student to a professional.

Source for data È HAYS. (2014). Oil & Gas Global Salary

Guide. Review of 2013, Outlook for 2014.

Photos È http://www.hemmera.com/ È http://vaeducation.kz/

14 Student Internship – Way of Spending the Summer!

å Student Internship –

Way of Spending the Summer!

Aneta Maruszak, Barbara Pach, Piotr Chojnowski

�Student internships are an opportunity to con-front skills acquired during studies with indus-try reality. Providing good student practices in a good company is often a real challenge for am-bitious young people. One seat – many takers – it’s a common situation, so the competition is stiff. The first practice is particularly impor-tant because then, for the first time, student has a chance to see "live" how the reality of work in the Oil & Gas industry looks. What is more, it’s an occasion to draw on the experience of em-ployees, which is priceless for students like us – standing on the brink of professional career. It also helps in choosing our career paths – it can both encourage and discourage.

Piotr: This summer I had a chance to be a part of Schlumberger’s Summer Trainee program. I spent two months in Ploiesti, Romania, working there at the company’s headquarter and it was probably the best summer I have ever had.

There are a couple of reasons for that: obviously, I learned a lot about the profession that I want to ex-ercise one day, and about the industry as a whole. I also had a chance to experience how a huge, in-ternational oil company operates and what it feels like to be a part of such a machine.

The most important reason for my delight, how-ever, is the fact that I got to meet all these fantastic people from all around the globe during these two months.

Being a part of a multicultural crew and making so many friends is just amazing and that unique experience is why I value working in oil industry so much.

Aneta: I would like to show how my practices looked, what surprised me most and how it affect-ed the choice of my career direction.

The duration of my internship was 4 weeks. I spent this time in a company engaged in the distribution of natural gas in Poland.

First step – recruitment!

�What counts in the recruitment process? Very often the deciding factor is the order of applica-tions. Sometimes the mean of grades from studies and some additional achievements such as active membership in a scientific circle also counts, which sets the bar a little higher. I’ve noticed that large companies prefer to recruit on-line, where-as if you want to apply for internships in a less-known institutions, it’s worth to go there in person – it significantly increases the chance of success. Questionnaires on-line have different forms: rang-ing from traditional ones where giving your basic personal data is sufficient to more specific, which require enclosing CV, covering letter and some-times an internship plan.

After receiving the initial consent for a traineeship in a company (in my case it was from the head of the institution), I was required to complete the rest of formalities in the Dean’s Office at the Uni-versity. Then an official cooperation between Uni-versity and the company was created.

In my case, the recruitment process went very smoothly. After sending just one email I got a permission to start my practice. Then everything went well – the only thing left was to wait for my fantastic internship!

Aneta Maruszak, Barbara Pach, Piotr Chojnowski 15

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7 o’clock – Good Morning!

�It’s 7 o’clock in the morning. I’m standing on the square which belongs to the company, where I’m doing an internship this month. It’s the time when working day for all gasworks employees begins. This also applies to us – trainees (there were also two other students, apart from me, doing intern-ship). We are surrounded by modern buildings with nice architecture.

As every morning, we direct our steps towards the place where executives and engineers reside to say hello to the manager. His office is at the end of a very long corridor, so during our trips to him, we meet minimum 90% of the entire staff before we reach our goal. And this time it’s not different. Each handshake is accompanied by hearty smile of workers, who are pleased to welcome future engineers in the industry. Finally we reach the last door. Knock, knock! I timidly open the door, but there is a client inside. Busy head of the com-pany, talking on the phone, asks us to wait for a while using his body language. After a few minutes we’re invited to come in. Quick greeting and we smoothly move to the organizational matters. "So what do you want to do today?" – the head asks. Every time he asks that question, our hearts beat faster. There are two options: doing office job all day or working in the field. We obviously prefer the second one. But, of course, we are aware of the fact that every engineer has to be familiar with technical documentation. It’ s very important but

unfortunately much less interesting than adven-tures in the field. It’s time for a verdict. Hurray! Today we’ re free from papers. The head gives us detailed guidelines and we’re free to go…

My first time modernizing a gas pipeline…

�About 8 o’clock an elderly gentleman comes into the room and calls us. We raise up from our seats immediately and then go outside. The field crew is bustling near garages. We are assigned to one of them and, in the blink of an eye, we’re sitting in a big off-road vehicle. The journey goes very pleasant, gasfitters tell us interesting stories that once happened to them during work. Some of them are so unbelievable, that it’s hard to believe that it really happened. Finally, we reach our desti-nation. Our task for today is to modernize the gas pipeline in the city center. Other teams from our division are already there.

Everybody shakes hand with each other and the work starts. That day we had the opportunity to see things which previously were available only on the pictures. Our aim was to remove an old section of the pipeline made of steel and replace it with a new one, made of polyethylene.

We were able to observe such processes as: butt welding, electrofusion welding and pipeline plug-ging. Our team willingly gave us valuable com-ments and responded to all questions. Everything


was going smoothly and soon the job was done, therefore we could take the lunch break.

Another experience – new connection to the natural gas network!

�Our next destination is a construction site, where a new housing estate is being built. Our task is to make a new connection to the natural gas net-work. This time we don’t have anyone to help us, because the work doesn’t require additional sup-port. And, one more time, we are pleased to see really interesting things. We can observe the show of welding skills made by one of our mentors.

Making the connection proceeds in stages. At first, a special flange is welded to a gas transmis-sion pipeline. After that the gasfitter drills a hole in the pipeline using a special drill. Then he joins an element, which enables a smooth transition be-tween steel pipeline and polyethylene one. Final-ly, he joins together the element described above with the pipeline, which will directly supply the

buildings with gas. He uses electrofusion welding process. The job is complete so we get in our vehi-cle and return to the company’s office, because the end of the shift will be soon. After saying goodbye to our today’s guardians, we turn to the manager’s office to give him a detailed account of what hap-pened today. After a short visit we’re free to go.

So this is how a typical day in gasworks ends. We were tired, but enthusiastically waiting for what the next day would bring.

My impressions

�These 4 weeks that I spent in gasworks gave me a lot of experiences and knowledge. I’m sure that I wouldn’t find it at any university. I had an occa-sion to work with people who spent sometimes more than 30 years working in this company. Their stories that describe in details how the industry has changed over the years are priceless. I’ve also learned how to maintain the documentation in the office. I could observe many interesting processes and complex installations, to which an ordinary citizen cannot get access. I could ask questions that bothered me at any time and I always received a satisfactory answer. What is more, I realized how to apply theoretical knowledge to professional realities. This experience helped me to make my career decision – now I know that my destiny is natural gas industry and it’s what I‘d like to do in the future.

Barbara: I’d like to tell you a short story and share my experience after 8 weeks as a Summer Trainee in Schlumberger… I bet there’s no one who has something in common with petroleum industry and no one ever heard about this compa-ny – the world's largest oilfield services company which employs approximately 126,000 people rep-resenting more than 140 nationalities working in more than 85 countries. And my destination was Romania and Well Testing Segment.

Keep calm and… you’ll deal with it!

�I remember the moment when I received a positive message after recruiting process and I re-

Aneta Maruszak, Barbara Pach, Piotr Chojnowski 17

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member how excited and afraid at the same time I was. As a student of petroleum geology with a background of environmental engineering I had almost nothing in common with what I was sup-posed to do during this internship as a Field Engi-neer trainee. Will I deal with it? Will I manage to communicate in English well? Anyway, I wanted to take this chance! It turned out to be challenging but very, very rewarding!

First steps

�Everything started in Bucharest where all the trainees from Continental Europe met for 3 days of introduction to Company. It was very good to get familiar with company’s policy and safety rules step-by-step. It also gave us a chance to get to know each other and spend some nice time together! As an integration we went together to the adventure park to climb in the trees and then we had dinner together. Some of us went to Italy, some to the Netherlands, Romania (like me) and one student went to Congo! I’d like to ask him someday about

his experience which could be much more inter-esting than mine!

What was my work?

�I spent most of the time in the headquarter, wearing my PPE and helping engineers to prepare tools before work. The segment I was working for was divided into several sub-segments supplying different services of testing. I was lucky to cooper-ate with very experienced people who introduced me to the project that the company was working on! But the most exciting part of my internship was one week spent in the wellsite, where I could watch the work and help with surface testing oper-ations on the new drilled wells.

Knowledge? Technical skills? OK! But the most important is attitude…

�When somebody asks me what is the most im-portant thing during internship, I’ll answer: atti-tude! I’ve learnt that there’s no stupid question to


ask. Moreover, there’s always so much to do even for inexperienced trainees – it’s just about the will to be active. By doing it you can gain both theoret-ical and technical skills at the same time. Theory is useless if there’s no practice. Each day was dif-ferent for me – I was helping with simple things, but when doing them I was asking for explanation: "how it works" and "what is this for". I wanted to use my time and learn as much as possible. I be-lieve it’s a right attitude we should have during internship.

It is good to be a woman in petroleum industry. True or false?

�Last summer a special edition of YoungPetro was published – it was dedicated to women in petroleum industry. We wanted to prove that girls in the oilfield is not something weird nowadays… We claimed that this might be an environment of work women can get used to. This summer I had a chance to experience it firsthand. After my internship I can tell that diversity is highly desir-able! However, work in this industry is not for everyone, of course. Undoubtedly – hard physical work with heavy tools is not for a woman and she won’t be able to do everything by herself. But it’s all about teamwork, good cooperation with boys. I met experienced girls, very good specialists, who were really satisfied with what they were doing.

They were full of passion! I met a short woman who was a boss of a team of big boys and she was doing really well! Furthermore, I was curious if it’s possible somehow to combine this petroleum work lifestyle with having boyfriend or family… I got to know that it’s hard but not impossible.

Internship – way of spending summer!

�"It’s the last 3-months holidays in your life – why aren’t you at the beach?" It’s a question which my colleague asked me and then I realized that I was finishing studies in the near future and I’d start a "real life" with work every day. Of course, in-ternship means no laziness – there might be some sacrifices to put into it. But I found this internship as a great fun, not only typical 8 or 12 hours of work. Free weekends gave me a chance to discov-er beautiful Transylvania and to spend some great time with my new friends from other countries. The diversity in international companies is some-thing fantastic! It’s amazing to eat dinner each day with new people from countries about which you hear for the first time and you don’t know exactly where they are on the map. I don’t feel like I didn’t have holiday – I was spending good time with new friends and visiting new places... And, when I came back home, there was still one month off left! I recommend this way of spending summer to everyone!

Vasyl Movchan 19

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· Combined Drill Bit with Selected Variable Step

Vasyl Movchan

�One of the problems that requires solution is the formation of ridges, such as pillars, collars and rails on bottom hole. Probably the most common solution for reducing the formation of ridges and reducing vibration is step reduc-tion of contiguous cutting elements or increas-ing the number of cutting elements, especially for hard rocks. Disadvantage of these technical solutions is that they are not applied to effect of block chopping and they also increase the spe-cific energy consumption and cost of the drill bit. Thus there is a need in the drill bit that has characteristics, which allow to prevent the for-mation of ridges on bottom that does not cause excessive vibration. That is why I projected the drill bit, which in its design includes 2 cutters and 2 blades with special planetary triangular tungsten inserts. It has been theoretically cal-culated and experimentally confirmed the im-pact of three different forces action to the bot-tom hole. Also have been optimized the effect of block chopping.

�As conclusions, I got complete removal of the formation of ridges on bottom hole, achieved maximum volume of reflected rock, significantly reduced the harmful longitudinal vibration of the drill bit.

Introduction�When we talk about the performance of the drill bit at the bottom then it evaluates many pa-rameters, the main ones are driving on bit, manual and scheduled drilling speed and cost of 1 drilling meter. The analysis of the theoretical and practical works on the application of universal rock cutting tool led to the conclusion – combining designs of drill bits provides increasing of bit driving and in-crease the service life of cutter.

The Main Material�One of the main directions of improving the efficiency of drilling oil and gas wells is usage new designs of drill bits, selected for specific geological conditions, and optimization of technologies for their labor. The efficiency of construction of deep wells depends on many components, one of them is the rational choice and usage of rock cutting tool. Cost and cycle time of building wells strong-ly depend on methods for evaluating efficiency during the formation and usage the park of rock cutting tools. The world's leading oil and gas com-panies use methods of evaluating the efficiency of drilling on such criteria as the minimum cost of 1 drilling meter.

Rock cutting tool is the executive body of the drill-ing process directly interacting with the rock. The efficiency of destruction process depends on its form and design features. Designing of rock cut-ting instrument closely associated with energy in-dicators of destruction rock. That's why I projected the drill bit, which in its design includes 2 cutters and 2 blades with special plug-planetary tungsten inserts triangular shape. Increases the penetration on drill bit previously created microcracks by pilot rods. This allows cutter, during its passage, sepa-rate larger particles. Thus reduce costs for energy for grinding particles of rock to "torment." And with pre-built microcracks increases cutter life.

* Ivano-Frankivsk National Technical University of Oil and Gas

ÞUkraine

[email protected]

* University Þ Country E-mail

20 Combined Drill Bit with Selected Variable Step

With the passage of mud solution through the holes in the blade begin to vibrate the connect-ed to each other inserts, thus generate ultrasonic waves, and depends on the different size of inserts, the waves frequency is fairly wide. Mud solution will pass through the blade and on both peripheral parts will be created a variable time pressures, so inserts will constantly generate ultrasonic waves. This will create a more destructive force on the face, which responds positively to the perfor-mance of drill bit.

Because holes blades will sharply decrease the side sectional area, respectively will increase sharply local velocity in a stream, leading to hydrody-namic cavitation on the bottom. The nature and intensity of the cavitation process depends on a large number of factors, whose impact is complex and not fully understood. Criterion for cavitation is a complex function of many variables. Existing criteria are not universal, but allow in the first ap-proximation evaluate the degree of development and the dynamics of the process [1]. The first – a cavitation number: k, accepted to count as:

kP P

Vex s v

st

=−×

212

( )[ ]. .

r

wherePex – static pressure at the exit of the hole in the blade, MPaPs.v. – the pressure of vapor saturation of the liquid, MPaVst – velocity of the fluid in the hole, m/s

The second parameter is the radius of cavitation bubbles. It is calculated based on Bernoulli's equa-tion.

rP

Vg

h h grin

=×

−××+ +

× × +

×× × −

2

2 8

22

1

2

2

σα

ρρ

ππΓ

[ ]

whereσ – surface tension of the liquid on the brink of gas (steam), N/mPп – pressure differential, MPaα – Coriolis’ coefficientV – velocity at the entrance to the hole, m/sh1 – oppression drop, m

hin – inertial pressure, mΓ – circulation speed, m2/sρ – radius-vector of fluid perturbations, m

The research allowed to determine the optimal size of cavitation bubbles. Determined that the optimum pressure difference for liquid of any den-sity is in the range 4–4.5 MPa (Fig. 1).

In 1909, Howard R. Hughes invented cutter drill bits for hard rock that radically changed the ex-ploration and drilling of oil and gas wells. After that, numerous improvement in the basic design of Hughes’ bit had been made. One of the prob-lems that require solution is the formation of ridg-es, such as pillars, collars and rails on bottom. The formation of ridges on bottom occurs, when the cutting element (carbides or steel tooth) falls into the same holes, which were made before by the same or other cutting element. This leads to poor drilling performance. As result, we have increased wearing out and reduced bit rate of sinking.

Generally known decisions of the formation of ridges on bottom are in increasing the load on bit, but as you can predict it reduces resource of bit because of the extra load on bit components. Probably the most common solution for reducing the formation of ridges on bottom and reducing vibration is step reduction of contiguous cutting elements, or increasing the number of cutting el-ements, especially for hard rocks. Disadvantage of these technical solutions is that they are not applied to effect of block chopping and they also increase the specific energy consumption and cost of the drill bit.

The formation of ridges on bottom can also be partly reduced by increasing of slippage cutting elements and improving their slaughter flowing wells by changing the geometry of the bit. The dis-advantage of this approach is that the cutting ele-ments in slippage and scaling will wear out faster, while the formation of ridges on bottom will not be eliminated completely.

Another solution to the problem of formation of ridges on bottom is the usage variable pitch

Vasyl Movchan 21

autumn / 2014

(angular distance between the axles) of cutting elements, such as proposed in U.S. Patent № 4,187,922. Any deviation from constant step can lead to a significant strengthening of bit vibration that will also lead to his premature wearing out. Also, the bit with small random deviations step may form ridges are almost the same as the drill bits with a constant step.

The formation of ridges on bottom can also be reduced by usage different configurations of cut-ting elements or teeth, including teeth with a T-shaped top for added wear resistance, when the teeth/plate crush a rock with reduced formation of ridges on bottom (for example, see UK Patent № 3,326,307). This method leads to a decreasing in drilling rate and increasing specific energy con-sumption (energy spent per unit of crushed rock) as cutting elements crushed rock with less speed sinking. Another option is grouping and place-ment of cutting elements with different steps in different groups, in combination with different orientation peaks cutting elements in different groups. This way you can reduce the formation of ridges on bottom, but it increases the cost of pro-duction, (see U.S. Patent № 2,333,746). Changes in the orientation of the cutting elements, as shown in U.S. Patent № 4,393,948, without optimal place-

ment on the surface of cutters can only reduce, but not completely exclude, the formation of ridges on bottom.

Ways to optimize the performance of drill bit by usage statistics and modeling for improving op-erating parameters of bits are illustrated in U.S. Patent № 6,213,225 and 6,095,262. In the absence of relevant theory are used specialized methods of modeling, but results of statistical optimization are limited by assumptions and input data, adopt-ed at the beginning of the optimization process. In addition, the known methods of modeling produce extremely inflated number of cutting ele-ments required for optimum rock drilling.

Thus there is a need in the drill bit that has char-acteristics, which allow to prevent the formation of ridges on bottom that does not cause excessive vibration, which can be economically acceptable manufacturing cost. One of the common disad-vantages of all known solutions is the absence of optimization in block chopping in drilling rock. The effect of block chopping is that rock has high strength properties at low compaction and strength characteristics of bending and stretch-ing in comparison to metal such as iron. Another common disadvantages of all known solutions are

�Fig. 1 – Determination the optimum pressure difference for liquid of any density


misinterpretations by specialists in the industry of true causes of harmful longitudinal vibration reso-nance frequency of cutter drill bit during drilling. The inventors have found the reason of harmful longitudinal vibration resonance frequency of drill bits.

The main object of the invention is to develop a design of cutter drilling tool with increasing of drilling performance, stability and speed of sink-ing at reducing the number of cutting elements, including in one embodiment the solid plates, compared to known cutter drilling tools.

Another object of the invention is to improve the design of standard cutter drill bit for drilling for si-multaneously improving productivity, endurance and speed of sinking with decreasing of cutting el-ements in comparison with known cutter drilling tools, which at that time made everywhere.

According to the present invention, the above ob-jectives can be achieved by mathematically deter-mined optimal arrangement of cutting elements on the surface of each of the cutters installed with

the possibility of rotation on the drill tool, or drill bit through the simultaneous usage the following principles [2]:

Complete removal of the formation of ridges on bottom during drilling through an independent cutter with variable pitch adjacent of cutting ele-ments.

Achieving maximum volume of reflected rock by optimizing the effect block chopping by choos-ing the optimal distance between successive implementation of tools based on mechanical properties of rocks to be drilled, cutting element geometry and orientation of the axis of the cutting element relative to the cutter surface.

Significant weakening of harmful longitudinal vibration resonance frequency of the drill bit or tool, which is a restriction of drilling rocks through optimal placement of cutting elements along the cutter generators.

In Fig. 2 shows the two cutter drill bit 1 with two blades 3. The bit 1 includes a body that has sliced on top of for connection to the drill rod. In body foreseen nozzle for cooling and lubricating the drill bit during the drilling process. At least one

�Fig. 2 – Side view many conical cutter in accordance with the present invention

�Fig. 3 – Cutting element

Vasyl Movchan 23

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cutter set to claw chisel and held in each of the sec-tions of casing bit with the possibility of rotation, while on the surface of the set of cutting elements arranged substantially in the form of crowns. Tungsten carbide plate secured by landing ten-sion in the holes or slots made in the cone. When connecting to a drill string drill rotates around its axis in the direction to destroy the rock. In blade tungsten inserts inserting triangular action which has been described previously.

Fig. 3 shows a side view many conical cutter 5 in ac-cordance with the present invention. Rolling cut-ter 5 includes a plurality of cutting elements, which in one embodiment are solid plate 11, inserted into planting holes made in the body of the cone and located substantially around the circumference of crowns 6–10 around the axis of cutter 12. Geome-try of cutting elements 11 may be varying in shape, size and orientation of the top.

Each cutting element 11 has an axis 17, and this axis 17 intersects at the same time surface and crown of cutter, there is situated given cutting element. The step is defined as the length of the arc along the circumference of the crown between the points of intersection of axles 17 with the curve on the sur-

face of the crown circle cutter 5 for adjacent cut-ting elements of the crown, oras an alternative, a step can be defined as the angle between the axes of adjacent cutting elements 17 for each crown.

Radii R1–R5 of each crown is defined as the short-est distance from the axis 12 of cutter to any point of crowns 6–10 on the surface of cutter 5. Radii R1–R5 is the maximum distance from the selected point of crown to the axis 13 of drilling bit 1, meas-ured along the perpendicular to the axis 13 of the drill bit 1. It is known that coefficient Kv, defined as the ratio of Ri to ri, should be equal to the whole number to reduce the formation of ridges on the face, where i = 1, 2, 3,...100% formation of the ridges on bottom occurs when the coefficient Kv is equal to a whole number regardless of the step of cut-ting elements 11. In order to avoid the formation of ridges on bottom with variable step and optimize block chopping of rock, the fractional part of the value Kv, according to the option, which is given advantage should be within 0…0.7.

Optimization of block rock 5, according to the present invention ideas, mathematically deter-mine the optimal step of cutting elements 11, arranged in rows, to obtain the largest rescued

�Fig. 4 – Cutting tools �Fig. 5 – Cutter according to the present invention


pieces possible for the selected cutters 5 and rocks undergoing drilling. More large the pieces, the more rock removed per unit ofexpended energy and the greater the cost savings, time, and energy. Location of cutting elements 11 closer than this op-timal range is, reduces the volume of rocks reflect-ed per unit of expended energy, the introduction of cutting element further than this optimal range is, leads to an increase in energy consumption, as chopping transformed into tearing.

Rolling cutter 5 is installed on the leg 2 drill bit and rotates around the axis 13 of bit towards 15. Several generators 16 are defined as the locus of points on the surface of the cutter 5, formed by the intersec-tion of the plane that passes through the axis 12 of the cutter 5, with the axis 17 at least one selected cutting element 17 and geometrical cutter surface 5. In other words, the generating is a curved line that covers the surface of the cutter during rota-tion around the axis of the cutter. At any moment in the process of drilling the main force interaction between cutter 5 and rocks going along the gen-erators 16. Thus, the optimal placement of cutting elements in the value of their density along the generators is crucial to reduce harmful vibrations.

Fig. 4, which shows type A in the direction of up-ward gaze on cutting tools, step cutting elements 11, defined as the angle between the axles of ad-jacent cutting elements 17, each crown gradually

increases from minimum step 19 to the maximum step 22. Moreover, all the steps are different, and the minimum step 19 and the maximum step 22 are nearby. In addition, the minimum steps 19 in all crowns 6–10 start randomly selected generatrix 18 of cutter 5, besides the displacement of generatrix 18 may not exceed 45°, and according to the vari-ant, 21 minimum half step. The same trend holds for all 20 rows 6–10 mentioned of cutting working body 5 from these minimal steps 19, starting from mentioned generatrix 18 and increasing to a max-imum steps 22.

Minimum steps 19 in all crowns 6–10 mentioned cutting body 10 may be equal or different. Maxi-mum steps 22 also in all crowns 6–10 mentioned cone 5 may be equal or different. Increasing from the minimum step 19 to maximum step 22 can be defined as arithmetic, geometric, exponential, log-arithmic or any other mathematical function and also as their combination.

For illustrative aims shown several generators 16, along which cutting elements 11 in all crowns 6–10 oriented with a deviation from generators 16 less than a half the maximum selected step 22 of crown, there the cutting element 11 is located.

Arc 26, shown by dashed line, is part of the cir-cumference of crown 7. This arc 26 measured from point A, which is the center of the selected step 23

�Fig. 6 – Volume of rocks reflected without optimization of block chopping

�Fig. 7 – Volume of rock reflected with block chopping

Vasyl Movchan 25

autumn / 2014

in crowns 7 towards 25, which is opposite to the direction of 29 rotation of the cutter 5. The starting point for the direction 28 is a line 24, which cross-es the step 23 in the middle point A. The end of the arc 26 is located within a certain step, marked as calculated step 27. Arc 26, the length of which is marked L, equal to the length circumference of mentioned crown 7 multiplied by fractional part of the coefficient Kv, and marked in the descrip-tion of present invention as KVD. For example, for r = 5 units and R = 7 units, Kv equals 7, divided by 5, or 1.4. Then the fractional Part Kv, marked as KvD, equal to 0.4.

L K D rv= ( ) [ ]2 32p

KvD cannot equal zero in order to avoid the for-mation of ridges on the face, and can range from 0.15 to 0.85. KvD, according to the variant, is in the range 0.3–0.7. The effect of block chopping rocks during drilling occurs, when the absolute value of the difference between the selected step 23 and his current pair as a variable step 27 will be more than 10% of absolute value difference between the maximum step 22 and the minimum step 19, both values are chosen for the crown 7. The foregoing

definitions for crown 7 can be represented as a mathematical relationship:

23 27 0 1 22 19 4− > −, [ ]

In this embodiment, in accordance with the prin-ciples of the present invention, the steps are calcu-lated as arithmetic progression as "minimal step" D*n, where D – constant, defined as the optimal value for maximum effect block chopping , and n – consecutive positive integers (n = 1, 2, 3, ...). In another group of embodiments in accordance with the principles of the present invention D can be changed so way to provide optimal placement of the cutting elements to reduce vibration.

Fig. 5 shows the cutter according to the present invention. Explanations to drawings are similar to explanations to Fig. 4, except that in this version of the invention cutting elements are made from the same material as the cutter, and are milled teeth 30. For illustrative aims chosen step 23 and its estimat-ed pair in the form of alternating step 27 shown for crown 9, instead of a crown 7, shown on Fig. 4. The effect is block chopping of rock in drilling occurs when the absolute value of the difference between the selected step 23 and its estimated pair in the

�Fig. 8 – Curves "distance-volume"


form of alternating step 27 will be more than 10% of the absolute value of the difference between the maximum step 22 and minimum step 19, both steps chosen for the crown 9. The foregoing defini-tion to crown 9 can be represented as a mathemat-ical relationship:

23 27 0 1 22 19 5− > −, [ ]

As an example of selecting the optimal variable step for optimization block chopping according to the present invention, a crown 9 select step 23 and calculate it in a couple of variable step 27. Arc 26

(shown dashed line) is part of the circumference of the crown 9. The length of this arc 26 measured from point A, which is the center of selected step 23 in crown 9, towards 28, which is opposite to the direction 29 of rotation of the cutter 5. The end of the arc 26 is within a certain step, marked as a settlement step 27. Arc 26, the length of which is marked L, equal to the length of mentioned circumference of crown 9, multiplied to the frac-tional part of the coefficient Kv, and marked in the description invention as KvD.

L K D rv= −( ) [ ]2 64p

�Fig. 9 – Schematic diagram of one cone cutter

Vasyl Movchan 27

autumn / 2014

Fig. 6 illustrates the volume of rocks reflected without optimization of block chopping (known solution). If the distance between the previous and subsequent implementation of cutting elements is not optimized, the volume of rock and depth of implementation are minor with no effect of block chopping. Based on the definition of block chopping according to the present invention, it is impossible to cause block chopping with constant step, which is usually used in wide-known cutter drill bit.

Fig. 7 shows the volume of rock reflected with block chopping, caused by optimal distance be-tween the previous and subsequent implemen-tation of cutting elements. Block chopping opti-mized for the crown when at least 20% of the steps are mathematically defined pair that satisfies the definition block chopping according to the pres-ent invention. In one preferably embodiment, all steps of the crown with pairs that satisfy the defi-nition of block chopping according to the present invention.

Fig. 8 illustrates the volume of reflected rock as essentially convex functional dependence on the distance between the previous and subsequent implementation of cutting elements for certain rock. Each type of rock (soft, medium or solid) has its own graphics curve "distance-volume" form of which depends on the physical and mechani-cal properties of rocks for this type of cutting el-ements and the drilling features. Block chopping is optimized when the volume of reflected rock is maximum [3].

Fig. 9 shows the schematic diagram of one cone cutter 5 and location of mathematically defined steps 27 relatively to the selected step 23 crown 10 of the present invention, as described in relation to Fig. 2–4.

The cutting element 11 of crown 10 of cutter 5 in-teracts with the bottom of well along the path 33, making a hole 3 in bottom of well by implement-ing of cutting elements in the drilling process.

The distance between adjacent holes 32 along a circular path 33 with radius R5 equals the distance between the adjacent cutting elements 11 in the crown 10.

If a pair of steps 23 and 27 in crown 10 is calculat-ed according to the ideas of the present invention, then at any randomly selected area 31 along the path 33 implementation in bottom of well by cut-ting elements which have the step 27, will follow for introduction of cutting elements with step 23 in such way that the optimal difference of steps will effect the block chopping and eliminate the formation of ridges on bottom in the drilling pro-cess.

Variable step increases efficiency of chopping dur-ing rock drilling, so even those cutting elements that come in contact with slippage, but not with full implementation, facilitate the destruction of rocks, compared to bits with constant step. In one embodiment of the present invention cutting ele-ments 17 in all crown cone 5 along the generatrix 16 relatively to the displacement of the generatrix 16 less than 51% of the selected minimum step 19 for any of crowns engaged by cutting element 11, which leads essentially to eliminate harmful longi-tudinal vibration resonance frequency of drill bits 1 to axis 13.

If cutting elements 11 are installed along mentioned generatrix 16 not according to the ideas of the pres-ent invention, then harmful longitudinal vibration of resonance frequency of drill bits 1 negates the benefits of block chopping , therefore, objectives of this invention cannot be achieved.

References1. Bielecki, V.S. (2004). Small Mining Encyclopedia. Donetsk, Ukraine.2. Boyko, V.S. (2004). Development and Exploitation of Oil Fields. Ivano-Frankivsk, Ukraine.3. Pokrepin, B.V. (2003). Develop Oil and Gas Fields. Moscow, Russia.

28 Smart Way of Mitigating Drilling Problems

· Smart Way of Mitigating Drilling Problems.

Review of UBD vs. MPD. Case Study

Mian Tauseef Raza

�The economics of exploration and production processes continue to encourage use of new methods to reduce drilling problems and costs. Underbalanced technology is one such method that provides an effective solution to address the conventional drilling problems like loss cir-culation, formation damage, pipe sticking, etc. UBD is a procedure used intentionally to drill oil and gas wells where the equivalent circulating density (ECD) of drilling fluid is less than the pore pressure of the formation being drilled. In many UBD operations, additional benefits are seen because of reduction in drilling time, good ROP, increased bit life and rapid indication of potential zones.

�Different operators have selected UBD and MPD with the goal of minimizing severe loss circulation and other drilling related problems associated with conventional over balanced drilling. MPD refers to being at balance or marginally over bal-ance in most of the open hole. In our case study we have compared two different wells A and B in a reservoir. A Well has been drilled with UBD as well as with MPD. While determining whether UBD or MPD should be applied as solution, the benefits and limitations of each should be both quantita-tively and qualitatively considered, and a decision should be reached depending upon the merits of each technique.

UBD and MPD both address drilling problems and can reduce NPT by minimizing losses, differ-ential sticking and time associated with well con-trol events typically associated with conventional overbalanced drilling. Where the primary drivers are the reservoir benefits, underbalanced drilling has been found to be the best option.

Introduction�There is some debate in the industry as to what constitutes MPD and UBD and whether one is a subset of the other. While all drilling can be considered a form of "managed pressure drilling," since the pressure must be controlled or "man-aged" for safe drilling, the industry has adopted this terminology to specify certain drilling prac-tices different from conventional overbalanced drilling. The IADC has defined managed pressure drilling as "an adaptive drilling process used to precisely control the annular profile throughout the wellbore." MPD objectives are to ascertain the downhole-pressure environmental limits and to manage the annular pressure profile accordingly. An underbalanced drilling operation is described as "an operation in which the hydrostatic head of a drilling fluid is intentionally designed to be lower than the pressure in the formations being drilled." For the purposes of this paper, the difference be-tween UBD and MPD is that for UBD, the target bottomhole circulating pressure is maintained below the reservoir or pore pressure throughout the openhole section, while for MPD, the target bottomhole circulating pressure is designed to be at or a little above the pore pressure throughout the openhole section. There are some exceptions such as when there are several formation pressures in the openhole section; however, the objective in MPD is primarily to preclude influx from the

*Univ. of Engineering and Technology Lahore

Þ Pakistan

[email protected]


Mian Tauseef Raza 29

autumn / 2014

formation while drilling, while the opposite is the case with UBD.

For the purposes of this study, the difference be-tween UBD and MPD is that for UBD, the target bottom hole circulating pressure is maintained below the reservoir or pore pressure throughout the open hole section, while for MPD, the target bottom hole circulating pressure is designed to be at or a little above the pore pressure throughout the open hole section. There are some exceptions such as when there are several formation pressures in the openhole section; however, the objective in MPD is primarily to preclude influx from the formation while drilling, while the opposite is the case with UBD.

Problems Associated with Conventional Drilling�The main problems incurred during conven-tional drilling are:

È Formation damage È Loss circulation È Differential sticking

È Less ROP and reduced bit life È Underbalanced Drilling (UBD)

UBD Provides a Rapid Indication of Productive Reservoir Zones

�Since the hydrostatic pressure of the circulating fluid system in a truly Underbalanced operation is less than the formation pressure to be drilled, a condition of net outflow of formation fluids (oil, water or gas) should occur given sufficient forma-tion pressure and in-site permeability. Proper flow monitoring of the produced fluids at surface can provide a good indication of a productive zones of the reservoir and act as a valuable aid in the geo-steering of the well (if horizontal application).Significant production of the liquid hydrocarbons (because gas is usually flared) during the drilling operation may provide some early cash netback to partially defer some of the additional cost associ-ated with UBD operation.

Ability To Flow/Well Testing While Drilling

�Recently, several operators have taken advan-tage of the flowing conditions occurring during drilling UBD to conduct either single or multi

�Fig. 1 – Drilling window


rate draw down tests to evaluate the productive capacity op the formation, and formation proper-ties during the drilling operations ( either in static mode or while drilling ahead in some situations).

Drilling Related Advantages of UBD

È No lost circulation È Minimized or eliminated formation damage È Drilling speed increases by 2 to 5 folds È Drilling bit life is increased È Less chances of pipe sticking È For UBD upper limit is defined by pore pres-

sure and lowest limit by collapse pressure designated by borehole stability. Typically the degree of underbalance is also defined by optimum operational envelop for the res-ervoirs drilled, amount of influx the surface equipment can handle, well geometry and design of system. The lower limit for man-aged pressure drilling is either pore pressure or collapse pressure or a combination of these keeping in view the formation under consideration and the upper limit is defined by fracture pressure.

Reservoir Related Benefits

È No need to clean up the well after drilling (stimulation job is not required)

È Reduced plugging of rocks in the reservoir leads to an increase in production of up to 5 times when compared with conventional drilled wells

È Able to find the most productive zones of the reservoir while drilling

Underbalanced Drilling Well Control

�Underbalanced drilling is different, but not con-sidered unsafe when compared to conventional drilling. During UBD drilling the hydrostatic pres-sure in circulating down-hole fluid system is inten-tionally kept below the pressure of formation being drilled. The well is designed so that the annular pressure (both static and dynamic) is deliberately maintained at a value less than formation pressure. If formations having permeability and porosity are

encountered, the system is designed to allow to form the formation into the wellbore. The primary well control function of the mud column is replaced by combination of flow and pressure control. Bot-tom-hole pressure and return well flow are contin-uously measured and controlled by means of re-spectively, pressure while drilling measurement and volume measurement in the closed loop system.

Schematic representation of UBD closed loop cir-culating system as shown in Fig. 2. The complete UBD system comprises of the drill pipe circulating system, a rotating control device, a UBD chock manifold, a separator and flare pit, none return valves in the BHA to prevent back flow up the drill string. In case of UBD, BOP’s are still considered as secondary well control equipment.

Whatever the case, the primary indictor of kick in UBD drilling operation is increased flow rate.

È Higher permeability than expected will result in a higher flow rate

È Higher reservoir pressure than expected leads to a higher differential pressure (drawdown) relative to the target bottom-hole drilling operations which in turn result in a high flow rate.

Secondary kick indicators in underbalanced drill-ing operations are:

È Increased choke pressure with no choke set-ting change

È Change in bottom hole pressure with no change in surface controls

È Higher rates of penetration

The influxes from the well bore during drilling are controlled through rotating control device and the drilling non return valve.

Rotating Control Device

�The RCD is a drill through device with a rotat-ing seal that contacts and seals through the drill string for the purpose of controlling the pressure or fluid flow to surface. This valve avoids the rush-


autumn / 2014

ing of formations fluid to surface. RCD failure can result in an uncontrolled release of fluids to sur-face. To ensure this does not occur, proper sizing and selection of the equipment is critical.

Non-Return Valve

�The drilling NRV is a type of back pressure valve installed in the drill string that provides positive and instantaneous shutoff against high or low dif-ferential pressure from the well bore thus ensuring continuous control of flow during drilling.

Managed Pressure Drilling�Managed pressure drilling or MPD: "An adap-tive drilling process used to precisely control the annular profile throughout the well bore. The ob-

jectives are to ascertain the down-hole pressure environment limits and to manage the annular profile accordingly." A more detailed description of the MPD process with focus on bottom-hole conditions would be: performance of drilling op-erations with a controlled annuals and controlled returns to surface using an equivalent mud weight that is maintained at or marginally above forma-tion pressure by manipulation of a dedicated choke device. The purpose of drilling a well using MPD technique with primarily to enhance the well construction process by minimizing drilling prob-lems.

MPD Candidate Selection

�Since the primary driver for MPD is to resolve drilling problems, it is necessary to determine whether MPD has the capability to deliver the re-

�Fig. 2 – UBD Surface Installations


quired results under the specific reservoir condi-tions.MPD is preferred in an area where well-bore stability issues are of key importance. Secondly, for narrow drilling window between fracture and pore pressure MPD is considered as the optimum option for drilling.

MPD Benefits

�MPD can provide us drilling as well as reservoir benefits like:

Less formation damage as compared to conven-tional drilling

È Improved rate of penetration È Minimized differential sticking È Limited lost circulation È Extended bit life È UBD and MPD comparison

MPD and UBD are both focused on controlling bottomhole circulating pressure during drilling; however, the two methods differ technically in how this is accomplished. Whereas MPD is de-signed to maintain bottom hole pressure slightly above or equal to the reservoir pore pressure (i.e. overbalanced or at balanced drilling), UBD is de-signed to ensure that bottom hole pressure (BHP) is always below the reservoir pore pressure (i.e. underbalanced drilling), so that it will induce formation fluid influx into the wellbore, and sub-sequently, to the surface. UBD, on the other hand, has long been employed to solve both drilling-re-lated and reservoir-related problems. The prima-ry difference, therefore, between UBD and MPD

concerns the degree of resolution attainable with each method for both the drilling-related and reservoir/production-related problems. MPD is often seen as easier to apply compared with full UBD operations. Often, in non-reservoir sections, MPD design requirements may determine that a simpler equipment package will satisfy safety con-siderations for the well, and therefore, the day rate would be reduced compared to going all the way to full underbalance. Another consideration is that in UBD, if there is multi-phase flow, the gas phase interferes with certain logging-tool measure-ments, which typically would not present a prob-lem in an MPD operation. As has been described, equipment requirements for both operations vary considerably, depending on the design parameters of the project. In many instances, the same equip-ment setup is necessary for UBD as well as MPD methods.

Drilling Benefits

�Historically, the major reason for companies to explore alternative drilling techniques such as UBD and MPD has been the incapability to drill the well using conventional overbalanced drilling (OBD) methods. Drilling problems that have driv-en the use of UBD or MPD techniques in the past have included:

È The need to minimize or eliminate formation damage

È Small formation pressure/fracture gradient window

È Desire to minimize well cost by:

Serial No. AreaDrilling Days (Conventional) Drilling Days

Contractor A Contractor B MPD Drilling

1 Area 1 188 228 166

2 Area 2 231 243 117

3 Area 3 146 - 69

4 Area 4 153 155 114

5 Area 5 126 124 81

Table 1 – Comparison of drilling days of MPD for 10 wells average with OBD in the same area


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1. Minimizing fluid losses2. Eliminating differential sticking

È Increase the rate of penetration È Extended bit life, etc. È Increase safety in drilling operations

Additionally, both UBD and MPD have the po-tential to reduce drilling fluid costs significantly through the use of cheaper, lighter fluid systems and elimination or significant reduction of mud losses. To summarize, two of the primary reasons for selecting MPD over UBD are 1) wellbore insta-bility concerns during UBD, and 2) the desire to reduce equipment requirements to improve cost efficiency. However, basing the decision on just these criteria ignores the possibility that signifi-cant reservoir benefits also could be realized with UBD and that equipment requirements really de-pend on the reservoir to be drilled, since in some cases, MPD may require an almost equivalent set-up as UBD.

How UBD is Solving Drilling Problems Around the World?�The subject problem has been studied under different scenarios which are given below:

Case 1: Underbalanced drilling in Mexico prevents circulation losses, reduced formation damage in highly fractured carbonates

Location: Reforma, Southern MexicoFormations: Upper, Middle and Lower Creta-ceousDepth: 9,000 ftPore Pressure: 4,500 psiWell type: Directional, DevelopmentHole-size: 7.5 inNo. of wells: 1

Objectives

È Reduce circulation losses È Reduce formation damage

È Prevent differential sticking

Results

È Use of invert emulsion and nitrogen in a two-phase system prevented circulation losses by reducing extremely overbalanced pressure previously encountered with conventional drilling

È Drilling underbalanced minimized formation damage and expedited nitrogen and pro-duction testing of well compare to the other wells in the area

È Drilling underbalanced mitigated the drilling hazard of differential sticking encountered in offset wells

Case 2: UBD Improves rate of penetration and reduces No. of bits to drill Barnett Shale

Location: Tarrant and Wise Countries, TexasFormations: Barnett shaleDepth: 7,499 ft TVDWell type: Vertical gasHole-size: 8-3/4 inNo. of Wells: 2

Objective

È Increase penetration rate from a well average of 40 to 80 ft/hour

È Decrease no. of bits required from an average of 3

È Provide better definition of formations seen on logs

Results

È Averaged a penetration rate of 80 ft/hr. È Reduced number of bits required

Cost-benefit Analysis�The cost-benefit analysis is an evaluation of the total estimated incremental costs and associated time for the application of the MPD techniques as


compared to the value of the benefits of the use of these techniques. This analysis requires collec-tion of vendor and operator estimates of MPD and other equipment costs, personnel costs, study and training costs, and estimates of the duration of incremental tasks within the well program as related to changes due to MPD application. Addi-tionally, the benefits of these techniques such as increases in ROP for particular well interval(s), reduction in wellbore related NPT, reduction in liner requirement and associated setting costs or other benefits will also have to be identified for the project.

A cost-benefit analysis is initially prepared for the Feasibility Study. This base analysis is fur-ther evaluated in subsequent Preliminary and Detailed Engineering and Implementation Plan-ning phase studies. As necessary, the cost-benefit analysis can be refined with modifications to the variable assumptions and the possible introduc-tion of additional variables within the model. Fig. 3 shows the comparative study of the MPD cots compared with conventional drilling carried by two different contractors. Plot shows the ap-plicability of MPD in a sense as to minimize NPT and thus reducing drilling days as it doesn’t in-volve drilling problems and results are within the economical range.

Conclusion�The following conclusion can be drawn as men-tioned below.

UBD and MPD technology reduced the NPT asso-ciated with drilling problems. No fluid losses, no tight hole or stuck pipe problems during UBD and MPD operations.

Each of these techniques has its place, and which solution is applicable depends on problems antic-ipated. MPD cannot match UBD in terms of mini-mizing formation damage along with characteriza-tion of reservoir, or identifying productive zones that were not evident when drilling overbalance; yet, when the objective is to mitigate the drilling problem, MPD can be as effective and more feasi-ble economically.

MPD is also preferable where well bore instability is an issue, when there are safety concerns from high H2S release rates, or when there are regu-lations prohibiting flaring or production while drilling booth techniques have applied in many types of formations containing different types res-ervoir fluids, different well types, and in different hole-sizes.

References1. Finley, D., Shayegi, S., Ansah, J., & Gil, I. (2006). Reservoir Knowledge and Drilling Benefits Compar-

ison for Underbalanced and Managed Pressure Drilling. SPE/IADC 104465, SPE/IADC Indian Drilling Technology Conference and Exhibition, Mumbai, India. October 16–18, 2006.

2. Guo, B., Lyons, W.C., & Ghalambor, A. Production Engineering Handbook: A Computer Assisted Ap-proach. Oxford, UK: Gulf Professional Publishing.

3. Murphy, D.J., Davidson, I.A., Kennedy, Busaidi, R., Wind, J., Mykytiw, C.G., & Arseneault, L. (2006). Applications of Underbalanced Drilling Reservoir Characterisation for Water Shutoff in a Fractured Carbonate Reservoir – A Project Overview. SPE Drilling & Completion, 21(03).

4. Oakley, D., & Conn, L. (2011). Drilling Fluid Design Enlarges the Hydraulic Operating Windows of Managed Pressure Drilling Operations. SPE 139623, SPE/IADC Drilling Conference and Exhibition, Amsterdam, The Netherlands. March 1–3, 2011.

5. O’Brien, T.B. (1979). Deep Drilling Problems – Some Causes And A Possible Solution. SPE-7850, SPE Deep Drilling and Production Symposium, Amarillo, TX. April 1–3, 1979.


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6. Rafique, M.A. (2008). Underbalanced Drilling: Remedy for Formation Damage, Lost Circulation and Other Drilling Related Problems. SPE 114186, SPE Western Regional and Pacific Section AAPG Joint Meeting, Bakersfield, CA. March 29 – April 4, 2008.

7. Ramalho, J., Medeiros, R., Francis, P.A., & Davidson, I.A. (2003). The Nimr Story: Reservoir Exploita-tion Using UBD Techniques. SPE-81623, IADC/SPE Underbalanced Technology Conference and Exhi-bition, Houston, TX. March 25–26, 2003.

8. (1996). Underbalanced Drilling and Completion Manual: Maurer Engineering Corporation.

Appendix AUBD – Underbalanced DrillingMPD – Managed Pressure DrillingNPT – Non-Productive TimeNRV – Non Return ValveRCD – Rotating Control DeviceWITS – Well site Information Transfer SpecificationMWD – Measurement While DrillingLWD – Logging While DrillingBHA – Bottom Hole AssemblyIADC – International Association of Drilling Contractors

36 Effect of Mobility of Oil in the Performance of Process Steam Assisted Gravity Drainage

· Effect of Mobility of Oil in the Performance

of Process Steam Assisted Gravity Drainage

Astrid Xiomara Rodriguez

�The process of steam assisted gravity drainage (SAGD, for its acronym in English) is based on the continuous injection of steam into the res-ervoir through two horizontal wells, where the lower well is the producer and the upper well is the injector; the spacing between the two wells is a function of viscosity. The base of the process is the formation of the steam chamber which is continually expanding, heating the formation fluids and thus by increasing temperature, the oil acquires mobility, draining in conjunction with the condensed water to the production well only by effect of gravitational forces.

�This technique has been widely applied in res-ervoirs with extra-heavy oil with viscosities higher than 10,000 cP, especially in Canada, giving both technical as favorable financial results, enabling in-creased extra heavy oil reserves, obtaining recov-ery factors greater than 50%. However, this tech-nique has not been implemented in mobile heavy

*Universidad Industrial de Santander

ÞColombia

[email protected]


�Fig. 1 – Sizing of the reservoir

Astrid Xiomara Rodriguez 37

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oils with lower viscosities because the viscous forces would influence the process, preventing the formation of the steam chamber and thus the mar-ketability of the process in this kind of oil crude.

In this paper, the results of the implementation of the SAGD technique to two reservoirs are com-pared, one with extra heavy oil with a viscosity of 254,814 cP and the other with mobile heavy oil with a viscosity is 4,019 cP, which will be shown the behavior of reservoir pressure and production oil rates, where the only production mechanism in the gravitational drainage.

A technical-financial analysis were performed from the result of numerical simulations of the SAGD process implementation in both types of hydrocarbons, based on the recovery factor, the steam-oil ratio (SOR), and the amount of steam re-quired as the part technical and the financial part is analyzed from the net present value. From these results the effect of the mobility of the hydrocar-bon in the feasibility of the implementation of the technique under SAGD operational parameters and design currently set is evaluated.

Introduction�The technique of steam assisted gravity drain-age has been implemented in reservoirs of ex-tra-heavy oil and bitumen, in which have achieved high recovery factors (above 50%), hence is creat-ed the need to implement this technique in heavy oil, which have mobility in the reservoir, since they are reservoirs that require recovery processes for producing the oil. SAGD is a striking technique because of the high recovery factor that can be achieved, so it is necessary to evaluate the tech-nical feasibility of implementing the process this kind of oil. The study presented is based on results of numerical simulation, where is analyzed the process based on the recovery factor and process steam-oil ratio, maintaining as only mechanism of production the gravity drainage and finally, pre-sents the financial assessment of the process in reservoirs with mobile hydrocarbons under the

design and operational parameters established for the development and implementation of SAGD.

Steam Assisted Gravity Drainage�The SAGD technique was developed by Dr. But-ler (1970) [1], who laid the foundation for the con-ceptualization and understanding of the processes that occurs when the steam has been injecting in an unconventional way, generating high produc-tion rates. Since then, the technique has been ap-plied to shallow reservoirs of extra-heavy oil with viscosities above 10,000 cP; the reservoir and fluid properties necessary to implementing the tech-nique are presented in Table 1, using the screening application.

Parameter Value

Viscosity, cP > 10 000

°API 10–21

Depth, ft 500–3 000

Kh, mD > 500

Kv, mD > 250

Thickness, ft > 50

hnet/hgross, % > 90

hshale, ft < 3

Thickness of the aquifer, ft < 3

Oil content, bbls/acre-ft > 500

�Table 1 – Screening of the SAGD technique [2]

The technique consists mainly of two horizontal wells: one located a few feet over the other where the upper well is the steam injector and the lower is the producer. This process employs as the only production mechanism of gravity segregation, lev-eraging mechanisms of conduction and convec-tion heat to warm the reservoir and the fluids pres-ent in it. Steam is injected continuously through the upper well with the aim of forming the steam chamber in which the oil is heated, thereby reduc-


ing its viscosity; the production is given by the difference of densities, where the steam will tend to rise to the top of the formation, while oil and condensate are mobilized in the opposite direc-tion toward the producing well.

This technique has been developed mainly for reservoirs of extra-heavy crudes, such as Hilda Lake, Jackfish, Senlac, Tia Juana where both tech-nical and economic results have been favorable. As most of the global reserves are of mobile heavy oil at reservoir conditions, they try to implement this technique in these reservoirs to increase reserves.

Numerical Reservoir Simulation�To analyze the effect of mobility on the perfor-mance of the technique SAGD, two models sim-ulation were created with the same dimensions which vary in fluid properties, depth and permea-bility of the formation. Pilot area is 10.1 acres with a thickness of 80 ft, 200 ft wide and 2,200 ft long. It should be emphasized that the relationship be-tween the wide and thickness of the grid should be as close to one for to model the formation and expansion of the steam chamber. The sizing of the reservoir is shown in Fig. 1.

SAGD in the Reservoir with Extra Heavy Oil�Reservoirs and fluid properties were taken as reference in the several areas of Canada in which has been implemented SAGD. The properties of the model are presented in Table 2, in which the high viscosity of the crude is evident and hence their low mobility. The pressure gradient of the formation is 0.433 psi/ft which is the same for heavy oil.

The oil viscosity is 254,814 cP – it was measured to reservoir temperature: 53.6°F. The End Point of the relative permeability curve are: Swir=0.2, Soir=0.2, Sorg=0, Sgr=0, Krwo=0.4473, Krocw=0.9942, Krgro=0.9567.

The vertical spacing between wells is 16 ft which is defined depending on the oil viscosity, as if this increases the wells must be closer. The total length of the well is 1,848 ft. It is necessary to highlight the well completion, as it has a single casing and two tubing within him, which inject or produce de-pending on the stage of the process where you are. The casing is slotted in the horizontal section of the wellbore and tubing (long and short) injected or produced by its ends.

�Fig. 2 – Injection and production scheme in the Star Up stage


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Property Value

Depth, ft 670

Thickness, ft 80

Area, acres 10.1

Porosity, % 30

Permeability, mD 5 000

Kv/Kh 0.5

Initial pressure, psi 290

Soi, % 85

Initial temperature, °F 53.6

Viscosity, cP 254 814

°API 6

�Table 2 – Reservoir and fluid properties of the extra heavy oil model

The SAGD process is essentially based on two stag-es, "startup" and "development". Startup stage con-sists essentially of the circulated steam by the two horizontal wells to achieve connectivity between wells, due to the high viscosity of the hydrocar-bon. Ideally, this step is as short as possible due to the high investment in the steam injection and low oil production.

For this model, the startup period lasted only three months in which steam is circulated at a pressure of 435 psia at a rate of 700 bbl/day for long tubing and the oil is produced at a pressure of 350 psia through the short pipe as shown in Fig. 2.

After reaching the connectivity between wells, the development stage is initiated, in which the steam continue to be injected through the upper well and both the heated hydrocarbons as the water condensed arrive by gravity to the producer well. The main phenomenon of this stage in the forma-tion, growth and expansion of the steam chamber. It is necessary to ensure that the production well is at the lower temperature than the temperature of the injected steam for the formation of the steam trap and/or liquid pool, which is to maintain a vol-ume of liquid surrounding the lower well for that steam does not move directly toward the produc-er well for that steam to expand and condense on site, and transferring its heat to the formation.

For this stage both the short and the long tubing of the upper well inject steam and the tubing of the lower well produce. The conditions of injection and production are remaining equal to the Start up stage unlike injection rate which was increased to 1,700 bbl/day.

�Fig. 3 – Temperature profile in reservoir with extra heavy oil


In the Fig. 3 are presented a longitudinal section (a) and two transversal sections (b, c) in which the distribution of the temperature of the reservoir is shown.

In Fig. 3a, we can see a longitudinal section of the well to three months into the process in which it is noted that there is already a connectivity be-tween wells, so that development stage can start. In Fig. 3b forming the steam chamber is observed, which a one year into the project reaches the top of the formation, at this point of the process is where the highest rates of oil production is reached. Al-ready at 5 years (as shown in Fig. 3c), the steam chamber reaches the limits of the model, so the model is analyzed until 2020.

Fig. 4 shows the behavior of pressure, recovery factor, production of oil and the steam-oil ratio (SOR) versus time respectively. In them we can see that the reservoir pressure initially increases and then remains constant, ensuring that the only

production mechanism are the gravitational forc-es and that viscous forces don't affect the process. Regarding the recovery factor, it is analyzed until 2020 that is the time when the steam arrive to the boundaries of the reservoir, just as at that time is reaches an oil-steam ratio of 8, at which point the project economically isn't profitable, reaching a recovery of 65% of the oil in place, which shows us the success of this technique to implement this type of oil. As mentioned previously, in the first year are reached the maximum rates of production at which point the steam contacts the top of the formation.

The financial evaluation of the technique take into account a CAPEX of $1.5M, which includes drill-ing costs and the adequacy of the wells; steam generation price of a MBTU is $7.5/bbl in which include the expenses and depreciation of the gen-erator, water treatment before vaporizing, staff, installation of tanks, etc. The Removing price was $35/bbl, here the lifting cost and the cost of

�Fig. 4 – Behavior of the pressure, recovery factor, oil production and steam-oil ratio


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transportation are taken into account, considering it is a high viscosity oil. The price per barrel was assumed $52/bbl, free of royalties and taxes.

In the Fig. 5 is presented the graph of the net pres-ent value of the project, where we obtain a gain of $3,852.28MM, calculated from the above data. From this, we can evidence the both technical and financial feasibility of implementing SAGD in very viscous oils due to high gain compared to the in-vestment.

SAGD in Reservoirs with Mobile Heavy Oil�The sizing and grid of the simulation model mobile heavy oil is the same as the model of ex-tra heavy crude, however, being oil with the lower viscosity, the reservoir is located at a greater depth and thus the formation permeability decreases, taking in an oil reservoir with a viscosity of 4,019 cP. Table 3 presents the main both fluid and reser-voir properties assigned to the simulator.

The well spacing is 40 ft higher than the heavy crude because the oil is less viscous. Similarly, as the fundamental principle of the startup step is to achieve connectivity between wells, for heavy oil is not necessary to do it because the oil already has sufficient mobility in field to displace it to the producing well.

In the development stage injected 2,000bbl/day of water at a pressure of 1,200 psi with a 60% quality, in terms of production, the temperature differen-tial between wells is 50°F which allows the for-mation of the steam trap, producing a pressure of 900psia.

The temperature profile at three different times are shown in Fig. 6. A longitudinal section of the reservoir is shown in Fig. 6a, where evidenced at 4 months into the process that the steam stays in the top of the reservoir due to density differences, which shows overriding initial steam preventing the formation of the steam chamber. Fig. 6b shows the thermal connectivity between the two wells in a year of the process, where the reservoir heating is observed in the vicinity of the upper well, starting

�Fig. 5 – Net Present Value in the project SAGD applied to a reservoir with extra heavy oil


to heat the lower well with the fluid being inject-ed, however no formation of the steam chamber. In Fig. 6c we can see the steam chamber formed to the 5 years of the project, the steam chamber was formed late but expands rapidly, reaching to contact the boundaries of the reservoir at 6 years into the project.

PROPERTY VALUE

Depth, ft 2 000

Thickness, ft 80

Area, acres 10.1

Porosity, % 30

Permeability, mD 800

Kv / Kh 0.5

Initial pressure, psi 900

Soi , % 85

Initial temperature, °F 105

Viscosity, cP 4 019.6

°API 13

�Table 3 – Reservoir and fluid properties of the mobile heavy oil model

In the technical analysis of the project (Fig. 7) we can see that although you can obtain the high recovery factors, the steam-oil ratio is very high, where the three years of the project, i.e. in 2017, already reaches a SOR of 8 which limits the im-plementation of the technique to this date, time in which only reached a recovery factor of 35%. Similarly, if we analyze the project up to 5 years at which time the steam reaches the limits of the reservoir, the recovery factor is 50% with a SOR of 10, however, as will be shown below – the project generates losses.

In terms of financial evaluation, the CAPEX, the price of generation of MBTU and the extracting cost of crude remained the same as those used in the analysis of extra heavy crude, i.e. $1.5M, $7.5/bbl and $35/bbl respectively. As for the price of a barrel, it was taken from $60/bbl (higher than the extra heavy crude because the oil is less vis-cous). In the Fig. 8 is presented the graph of the Net Present Value of the project in which it is evi-dence that under these conditions are reached lost around $365.9M.

As you can see, technically the project can be prof-itable, since you are injecting steam into the res-

�Fig. 6 – Temperature profile in reservoir with mobile heavy oil


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�Fig. 7 – Behavior of the pressure, recovery factor, oil production and steam-oil ratio in the mobile heavy oil model

�Fig. 8 – Net Present Value in the project SAGD applied to a reservoir with mobile heavy oil


ervoir, and the temperature improves mobility of oil in the reservoir, thus allowing better recovery. However, the financial evaluation shows that the process is not profitable because high rates of in-jection compared to oil being produced , so reach-es the steam-oil relations higher.

Conclusions�The petrophysical characteristics of the rock and the fluid properties are important factors in the development of the technique of steam assist-ed gravity drainage since these govern the forma-tion and expansion of the steam chamber in the reservoir and thus the efficiency of process. Start-up phase is required to achieve the connectivity between the wells and allows gravity drainage of heated oil and condensates, however, it is neces-

sary to accelerate this step, as the oil production is minimal, and reflects in a high investment and low income.

The Process Steam Assisted Gravity Drainage is both technically and economically feasible im-plementation in reservoirs with extra heavy crude considering that although it is too viscous hydro-carbon, with SAGD can get to recover a high per-centage of OOIP giving a profit significant of the process.

Although the end of the SAGD process applied to the reservoir with mobile heavy oil, the steam chamber is formed and can reach a high recovery factor, the process is not feasible to implement to the existing conditions, since the amount of steam needed for its development is very high, which makes the project unprofitable.

References1. Albahlani, A., & Babadagli, T. (2008, March). A Critical Review of the Status of SAGD: Where are We

and What is Next?. SPE 113283, Western Regional and Pacific Section AAPG Join Meeting, Bakersfield, CA. March 31, 2008.

2. Butler, R.M. (1994). Steam Assisted Gravity Drainage: Concept, Development, Performance and fu-ture. Journal of Canadian Petroleum Technology, 33(02).

3. Chakrabarty, C., Renard, G., Fossey, J., & Gadelle, C. (1998). SAGD Process in the East Senlac Field: From Reservoir Characterization to Field Application. UNITAR Conference, Beijing, China. 1998.

4. Clark, B. (2007, July). Heavy Oil, Extra-Heavy Oil and Bitumen Unconventional Oil. NPC Global Oil and Gas Study.

5. Dusseault, M. (2008). Diplomado en Crudos Pesados. Modulo V: Gestión de Proyectos para el Desar-rollo de Campos de Crudo Pesado y Nuevas Tecnologías. Bucaramanga.

6. Dusseault, M. Hydrocarbon from Non-Conventional Sources: Heavy and Extra Heavy Oil. Waterloo, Canada: Waterloo University. Cap 2.1.

7. Elliot, K. & Kouscek, A. (1999). Simulation of Early Time Response of Single Well Steam Assisted Gravity Drainage (SW-SAGD).SPE 54618, SPE Western Regional Meeting, Anchorage, AK. May 26–28, 1999.

8. Grills, T., & Vandal, B. (2002). Case History: Horizontal well SAGD Technology in Successfully Ap-plied to Produce Oil at LAK RANCH in Newcastle Wyoming. SPE-78964-MS, SPE International Ther-mal Operations and Heavy Oil Symposium and International Horizontal Well Technology Confer-ence, Calgary, Canada. November 4–7, 2002.

9. Haskin, C., Bugno, W., & Miller, R. (1991). Shaft and Tunnel Access (SATAC). Concepts for Develop-ing Petroleum Reserves. SPE-22133-MS, International Arctic Technology Conference, Anchorage, AK. May 29–31, 1991.

10. Mendoza, H., Finol, J., & Butler, R. (1991). SAGD, Pilot Test in Venezuela. SPE-53687, Latin American and Caribbean Petroleum Engineering Conference, Caracas, Venezuela. April 21–23, 1991.


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11. Mercado, C., & Rosendo, M. (2001). Tesis de grado: Recobro Mejorado de Crudos en Pozos Horizon-tales Mediante el Método de Segregación Gravitacional Asistida por Vapor Utilizando un Solo Pozo (SW-SAGD). Bucaramanga, Columbia: Universidad Industrial de Santander.

12. Montes, E., & Pacheco, H. (2006). Tesis de grado: Aplicación de Nuevas Tecnologías para la Recuper-ación de Crudo Pesado en Yacimientos Profundos. Bucaramanga, Columbia: Universidad Industrial de Santander.

13. Rodriguez, E., & Orjuela, J. (2004, December). Feasibility to Apply the Steam Assisted Gravity Drain-age (SAGD) Technique in the Country’s Heavy Crude Oil Fields. CT&F. Ciencia, Tecnologia y futuro, 2(5).

14. Sandoval, R., & Jimenez, R. (2005). Nuevas Tecnologías para la Explotación de Yacimientos de Crudo Pesado. Informe de Investigación. Grupo de Investigación Recobro Mejorado (GRM).

15. Shen, C. (2000). Numerical Investigation of SAGD Process Using a Single Horizontal Well. Journal of Canadian Petroleum Technology, 39(03).

16. Singhal, A.K., Das, S.K., Leggitt, S.M., Kasraie, M., & Ito, Y. (1996). Screening of Reservoirs for Ex-ploitation by Application of Steam Assisted Gravity Drainage/Vapex Processes. SPE-37144-MS, Inter-national Conference on Horizontal Well Technology, Calgary, Canada. November 18–20, 1996.

17. Singhal, A.K., Ito, Y., & Kasraie, M. (1998). Screening and Design Criteria for Steam Assisted Gravity Drainage (SAGD) Projects. SPE-50401, SPE International Conference on Horizontal Well Technology, Calgary, Canada. November 1–4, 1998.

18. Trigos, E. (2010). Evaluación Técnica de la Factibilidad de Implementar un Proceso SAGD en Yaci-mientos de Crudo Pesado. Bucaramanga, Columbia: Universidad Industrial de Santander.

19. Vásquez, H., Sánchez, D., McLennan, J., Guo, Q., Portillo, F., Poquioma, W., Blundun, M., & Mendoza, H. (1999). Mechanical and Thermal Properties of Unconsolidated Sands and Its Applications to the Heavy Oil SAGD Project in the Tia Juana Field, Venezuela. SPE-54009, Latin American and Caribbean Petroleum Engineering Conference, Caracas, Venezuela. April 21–23, 1999.

46 Responsibly Energising a Growing World

conference | 21st World Petroleum Congress – Moscow 2014

´ Responsibly Energising a Growing World

Joanna Wilaszek

�The biggest E&P companies, the most impor-tant figures of the industry, wonderful events, marvelous people, interesting sessions, impor-tant business and beautiful places – these words can shortly describe what has happened in Moscow from 15th to 19th June 2014.

A place, were petroleum world meets

�World Petroleum Congress is always a great feast of knowledge, business and science. This year it was organized in Moscow, the capital city of Russia.

WPC Conference is one of the biggest events of the petroleum world. It creates a huge platform for meetings, discussions and exchanging opin-

ions. The congress participants could take part in various panels, sessions and discussions, divided into parts and thematic blocks. Some of them re-ferred to international problems, some to regional matters, there were also available panels concern-ing situation of one specific country. Sometimes it was very hard to decide which event to choose. Apart from panel sessions, simultaneously on the exhibit floor participants could visit stands of 542 companies and institutions.

For the five congress days Moscow greeted over 10 thousand people from 119 countries: politics,

representatives of 1,500 E&P companies and specialists of the energy sector. All of them took part in official panels and debates as well as talked

Joanna Wilaszek 47

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over recent issues of the industry while backstage discussions. Over 16 thousand people visited the World Petroleum Exhibition.

Youth participation

�Organizers had also in mind the youngest peo-ple of the industry – students and young profes-sionals. They realized that in the near future these young people will take the helm of the business and they need to be prepared perfectly well. This is the reason why organizers created the Youth Lounge, situated on the exhibit floor. This was a special youth center of the conference. There we could take part in presentations and discussions, get information about events being organized by the Youth Council and find a wide range of maga-zines and journals relating to our line of business. Apart from this we could use computers and take a rest, having a snack. All of these made our par-ticipation more important and we could really feel that we are a significant part of the Congress. But

it is not all – Organizers prepared also a special Volunteer Program for the youngest, active peo-ple. 544 Volunteers came from all over the world

to work together and take part in organizing WPC. We had a priceless chance to see the whole pro-cess from the backstage, which was a great expe-rience.

Great feats of culture, tradition and history

�But the events like World Petroleum Congress are also big cultural feasts. Russian organizers made their best to present all the participants the best side of Russia, its history and its culture. The first evening event was the Opening Ceremony organized at the Kremlin Palace. In this unusual place we could listen to the opening speeches and afterwards experience one of the best shows in history. That evening the Kremlin Palace became a concert hall for philharmonic orchestra, a dance floor for ballet and a few dance groups, a stage for choir and opera singers. All the artists were the best from the best. They showed a big portion of fascinating Russian culture.

The next event – Russian Night, organized in Gorky Park offered an overview of the Russian his-tory – from the very beginning until recent times.

48 Responsibly Energising a Growing World

It was presented by groups of people wearing well-matched costumes and showing customs and style of life in particular ages, from the very first years of settlement on Russian territory to modern days. Apart from this we could taste delicious food and relax in wonderful surrounding.

Organizers did not forget about the youngest at-tendees also in the matter of evening events. All attendees under 35 years received invitations for Moscow Fairytale Night at Izmailovo Kremlin, were a lot of attractions were waiting for them. A concert, dances, a wide range of social games, fight shows, traditional food and an occasion to learn about ancient way of life through garland weaving, wood cutting and so on. There was also an amaz-ing surprise – a special show with brown bear. It was a dream evening for meeting other young participants and another great lesson of Russian culture and history.

Closing ceremony on the last day brought us a portion of Turkish culture – dancers presented

amazing choreography, bringing closer emotions, which will be waiting for us in 3 years, during the next edition of WPC in Istanbul.

Priceless memories

�For us, student attendees, WPC was a wonderful conference, during which we could know people from both sides of the globe, participate in inter-esting panels, talk to representatives of the indus-try and experience amazing moments.

We could see problems and challenges of our industry from other points of view, better under-stand some problems, which the business have to face currently. Generally, we got a chance to look at our industry globally.

For sure everybody attending 21st WPC in Moscow will never forget the event.

The next edition of WPC will be organized in Is-tanbul, Turkey in 2017. See you there!

Maciej Wawrzkowicz 49

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How It Works?

Maciej Wawrzkowicz

Oil rigs or more officially oil platforms are known by all of us. While you are reading this article there are almost 900 rigs that continuously work all over the world’s oceans and seas (IHS data). Their in-credible power, huge mass, advanced technology and efficiency of working make them probably the most profitable structures in the world. How did they appear in the contemporary technology? How did the development of this constructions look like?

Let us start from the beginning. The first offshore drilling process took place in 1897. Originator of

this idea was H.L. Williams who used the pier in the Santa Barbara Channel located in California to support a land rig next to an existing field. The idea was developed in many ways and just five years later, there were 150 offshore wells in the area. When this method of drilling had become

popular among upraising oil investors and engi-neers, the offshore drilling was developed as sepa-rated exploration and production technique.

Creating a definition of the oil rig we may state that the offshore platform is a large structure with facilities that enable drilling wells, extracting oil and natural gas, and also temporarily storing the product. From offshore, hydrocarbons are trans-ported by pipelines (if platform is stationary) or more often is transported onshore by tankers in order to the refining process and distribution to customers.

There are several types of oil platforms depend-ing on depth of drilling: fixed platform, compli-ant tower, sea star, floating production systems, tension leg platforms and SPAR platforms. First of them – fixed platform – is built on concrete or steel legs anchored directly onto the seabed, sup-

50 How It Works?

porting a deck with space for drilling rigs, produc-tion facilities and crew quarters. Second – compli-ant tower structure consists of slender and flexible towers as well as pile foundation supporting a con-ventional deck for drilling operations.

Compliant towers are designed to sustain signif-icant lateral deflections and forces, and are typi-cally used in water depths ranging from 370 to 910 meters. Floating production systems known also as FPSO systems are platforms moored to location for extended periods, and do not actually drill for hydrocarbons but are used in order to storage pur-poses as well as host very little process equipment.

For drilling on the deepest water there are used SPAR platforms. Similar to an iceberg, the majori-ty of a SPAR facility is located beneath the water's surface, providing the facility increased stability. The main component of a spar facility is the deep-draft floating chamber or hollow cylindrical hull. The bottom of the cylinder includes a ballasting section with materials that weight more than sea’s water, ensuring the center of gravity is located be-low the center of buoyancy.

The illustration below shows the types of the off-shore rigs with advisable depth of usage (courtesy U.S. Minerals Management Service).

Of course the depth of usage revealed is not a rule. In many cases one type of the rig is constructed accordingly with the expectations of the operating company that had ordered it.

The biggest oil drilling platform is the rig called "Berkut" or "Golden eagle" and has been launched recently by Russia's Rosneft and America's Exxon-Mobil in the Okhotsk Sea in Russia's Far East. This monster was designed to work in harsh subarctic conditions. According to Igor Sechin, Rosneft’s president: "The drilling platform can withstand a 9 magnitude earthquake, waves of up to 18 me-ters and temperatures down to minus 44 degrees Celsius." "Berkut" is also able to withstand float-ing ice up to two meters thick and has an autono-mous power supply system. Construction weights 200,000 tons and can drill a total of 45 wells.

Who knows Dear Reader? Maybe it is your place to work on soon?

Call for Papers�YoungPetro is waiting for your paper!

The topics of the papers should refer to: Drilling Engineering, Reservoir Engineering, Fuels and Energy, Geology and Geophysics, Environ-mental Protection, Management and Economics

Papers should be sent to papers @ youngpetro.org

For more information visit youngpetro.org/papers

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SUMMER / 2013

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WINTER/SPRING / 2012

ISSN 2300-1259

AUTUMN / 2012

summer / 2013

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