МҰНайшы маусым 2013 3 Dear readers and colleagues!
Part three. Drilling and workover
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| Part three. Drilling and workover.
Drilling a well is a process that involves making a cylindrical opening in rock whose diameter is small compared to the well shaft length. Drilling equipment is used to carry out the process, without human access to the bottom hole. The start of the well, on the surface, is called the well head, and the bottom - the bottom hole, with the well walls creating the shaft. Drilling comes in three forms: vertical, slanted and horizontal. Horizontal drilling is considered the most complex technically. Wells have been drilled since ancient times. In fact, the first wells were drilled in China to produce water and saline solutions and were noted in the works of Confucius, about 600 BC. They were drilled to roughly 900 m. The dawn of oil production is considered to be burst for modern drilling, with the first oil well drilled by accident in 1826 in Kentucky in the USA, when looking for salt brine. The first “real” oil well in the USA was drilled in 1859 by Colonel E.Drake for the Seneca Oil Company close to the town of Titusville, Pennsylvania. After two months of work, oil had been found at a depth of 20 m, and this was the start of the oil industry in the USA. Until relatively recently, Drake’s well was thought to be the first oil well in the world, but documents discovered about the work headed by V.N.Semenov show that the first oil well was actually drilled in 1848 at the Caspian Sea Bibi-Eibat field. The first oil came on 14 July. Kazakhstan’s first oil appeared in 1899 when a gush of light oil appeared at the Karashungul field at a depth of 40 m. As we started producing oil in Kazakhstan at the end of the 19 th century, that makes us one of the oldest oil producers in the world - far earlier than Venezuela, Iran, Kuwait, Mexico, Norway or Saudi Arabia. In 1987, oil was drilled for the first time offshore - in the Pacific Ocean, close to Summerland Island (California, USA). In PetroKazakhstan, wells are drilled and repaired by the PKKR Drilling & Well Services Department, consisting of 80 people in 2 structural divisions - Drilling Department and Well Services Department. In 2012, PetroKazakhstan drilled 110 wells, including 56 production wells, 32 exploratory wells and 22 appraisal wells, which stretch for a total of 169,315 rm. In addition, 102 wells had been commissioned by the end of 2012. Drilling, like much other oil field work, is hazardous. For that reason, we asked some of our specialists to tell us about the drilling and repair process.
The first American oil well gushed oil at a depth of 20 m; the first Russian oil wells were drilled to a depth of at least 100 m. However, with the development of oil production, drilling depth has gradually increased, as oil has had to be produced from deeper and deeper horizons. For example, by the end of the 1960’s, in the USSR the average depth of production wells was 1,710 m. The deepest well in the world used in industrial production is a gas well in Texas, at 7,460 m. The deepest non-oil well is the Kolsk well, which is deeper than 12 km, and which is used for scientific and research purposes.
- PetroKazakhstan wells are drilled by contractors - Sibu-Kyzlorda LLP, Zhanros Drilling LLP, PM Lucas LLP, Bureniye & K LLP and NTS LLP, which own 10 drilling rigs between them.
- The well construction cycle includes a preparatory phase, erecting a platform and equipment; rigging up; the actual drilling process; well casing and plugging; formation drilling and testing for oil and gas influx. Preparatory work involves selecting a rig location, laying an access road and installing electricity, water and telecommunication networks. Then drilling rig and equipment are erected according to approved plans to ensure work is performed safely, the relevant maintenance checks can be performed and assembly costs are kept to a minimum. Rigging includes a test launch of the drilling rig to check the efficiency of all elements and units. The drilling process starts once a square section drill bit has been screwed on to the Kelly stem. A rotor turns to put the Kelly stem into motion, which in turn turns the drill bit. As the well shaft gets deeper, it is strengthened and plugged if necessary. Well strengthening involves dropping a casing pipe into the well and cementing it. Wells are plugged to prevent fluid seeping from unused horizons to within the casing, which is why all shaft rock cavities are filled in. Although, during the drilling process, productive strata have already been developed, they are ZJ30 мобильді бұрғылау қондырғысы / Мобильная буровая установка ZJ30 / Mobile Drilling Rig ZJ30
МҰНАЙШЫ Маусым 2013 51 isolated using casing pipes and plugging ensuring any oil or gas seeping into the well does not hinder further drilling. Once sinking has been completed, productive strata are reopened using perforation to ensure oil and gas influx. After this, the well is developed, i.e. oil and gas inflow is initiated. Well development, depending on specific conditions, may take between several hours and several months. Once oil and gas have appeared, the well is taken over by the operating team, and the rig is moved a few metres to drill a well pad (editor: a pad is 10-12 slanted wells covering one large oil field) or moved to the next pad.
- The whole process from the start of preparatory work until well completion takes about 15-18 days.
- In time terms, historically the quickest well drilled was at Aryskum-304, which took 6.5 days. It took us 86.7 days to drill the Tuzkol well and 108.4 days to drill the geologically complex Doszhan-24 well. In depth terms, the Aryskum 301 exploration well is the deepest, at 4,250 m. - What types of wells exist? - Wells are divided into smaller (up to 2,000 m deep), medium-sized (up to 4,500 m deep), deep (up to 6,000 m deep) and ultra deep wells (over 6,000 m deep). Depending on shaft axis and configuration, wells are divided into vertical, horizontal and slanted. PetroKazakhstan drilled its first horizontal well in March 2005, and PKKR now has 19 of them. PetroKazakhstan tends now to drill vertical wells. In the oil industry, wells are divided into investigation wells (which are then divided into exploratory, development and other wells) and operating wells. Operating wells can be categorised as production, injection, appraisal or control wells. Production and injection wells form the so-called operating well stock or operating wells. - What drilling methods are used at the PetroKazakhstan fields? - Wells can be drilled mechanically and non-mechanically (for example, using hydraulic and electric impulse methods). However, the industry currently only uses percussion and rotary drilling - the mechanical methods, as non-mechanical drilling is currently experimental. We use mechanical drilling at all our fields. - What difficulties do you come up against in deep-hole drilling? - The most common difficulties in drilling deep wells is that well walls tend to collapse, fluid is either lost or can appear in strata (i.e. leaks in); differential wall sticking by drilling and casing pipes is also among them.
- Drilling is one of the most important areas in well construction. It incurs the most time costs and, more importantly, monetary costs. That’s why, compared to other areas of accounting, drilling costs are grouped in the most detail.
The oil production industry is one of those that has no raw material costs. Oil deposits do not cost anything in the terms of feedstock expenses. However, drilling requires the use of a lot of different materials such as clay, cement, pipes, power, a lot of water used for technical purposes, and auxiliary services (to cement and test casing for permeability and to carry out electric assurance work). Together with equipment and apparatus lease costs, the above costs also include the cost of the wells themselves. The oil and gas industry is a capital intensive one as it incurs high costs for drilling, well operating and mechanisation. Currently, 5 drilling companies provide the PetroKazakhstan group of companies (PKKR, Kolzhan and PKVI) with 10 drilling rigs. As far as well repairs are concerned, our 16 units come from 6 companies. Then another 15 or so companies provide cementing, surveying, unit supervision, gas logging and other subsidiary drilling and well repair services. Zhanat Akhmetova , Material and Cost Control Specialist of Drilling Department, PKKR Liliya Umarova, Material and Cost Control Specialist of Drilling Department, PKKR 52 Маусым 2013 МҰНАЙШЫ - What new drilling technology has appeared in recent years? - Zhanros Drilling management closely follows innovations in the drilling & workover industry, and is always modernising both its equipment and techniques. For example, in 2012 we commissioned a new ZJ30 drilling rig, and even more recently we sent a brand new mobile ZJ40 rig to the Tuzkol field. They’re easier to use, i.e. both machines having more space for the driller in a closed cabin; using a joy stick instead of a steering wheel. The driller can observe drilling using video monitors. Working conditions have improved, productivity has increased, task performance has become clearer and safety is observed, all of which means the quality and speed of work has grown. Drilling and workover technology does not stand still. Drill bit and drilling fluid properties are constantly being modernised, along with the quality of drilling pipes, machines and mechanisms. One of the techniques with the greatest potential is probably coiled tubing, which is used in the continuous radial feeding of pipes into wells, significantly easing and speeding up drilling and repair work. Coiled tubing may be used to drill new wells, reopen strata, but it has the greatest technical and economic effect on drilling second slanted or horizontal shafts from existing wells. Flexible pipes help carry out drilling work in basins and increase well yield 3-8 times. Coiled tubing technology is popular due to its effectiveness and safety. Zhanros Drilling’s plans involve developing coiled tubing technology, which, by the way, will involve a lot of investment. It’s worth pointing out that our modernisation and favourable investment climate is supported by the European Bank for Reconstruction and Development, which is a close business partner and which has repeatedly provided us with some significant loans. Aleksey Myltykbayev, General Director, drilling company “Zhanros Drilling” LLP - How many wells on average does your division repair per year? - We carry out underground and major repairs on production and injection wells, and also develop newly drilled wells. This year, we are planning to complete the underground repair of 1,000 wells, which includes developing new wells; repairing wells with electro-centrifugal pumps, screw pumps and bottom- hole pumps; working at water-injection wells and also repairing temporarily closed wells so they can return to operations. Repairs are carried out using loaders provided by contractors. In 2013, we will use 16 loaders provided by DOS Engineering Ltd, Technology AlemOil LLP, RMZ-Shapagat LLP, Zhanros Drilling LLP, NeftTechService LLP and FracJet LLP. - One of the problems at our fields is water cut. How much time does a repair take after water has seeped into a well? And what are the most difficult situations? - Most repairs are carried out in production wells (electro-centrifugal, screw and bottom-hole pumps). In addition, more than 100 newly drilled wells will be equipped with our loaders. As far as a water-out is concerned, work to isolate water intervals in production wells takes an average of 229 hours.
- Sometimes wells that are no longer viable or casing of which cannot be repaired are closed temporarily or abandoned. Only a few wells require this type of work every year. Temporary well closure and abandonment are needed to ensure the safety of those working there and to protect the environment. Sariyev Talgat, Deputy manager, Workovers, PKKR Thank you for your interviews! - Which technical projects were developed and implemented in 2012 and which ones in 2013? - To drill a well you first of all need to draft a technical well construction plan. Technical well construction plans are drafted for groups of wells (within a single field) at specific depths, and indicate the type of drilling rig and well construction to be used. In 2012, PetroKazakhstan carried out drilling work, mostly exploration and operating wells, based on six group technical plans. For example, operating wells were drilled at the North-West Kyzylkiya field to a planned depth of 1,600 m, exploration and operating wells - at the Karaganda block and Aryskum pocket to planned depths of 1,500/2,750 m and 2,250/3,250 m, respectively. Operating and horizontal wells H-3 and H-4 were drilled at the Kyzylkiya field. These projects will be continued in 2013. In addition, due to changes in technical data and well depth, three group plans were also drafted. Exploration and operating wells are currently being drilled at the Doshan and Bukharsai fields, and operating wells - at the North Nuraly, Maibulak and Aryskum fields. A horizontal well was also drilled at Aryskum according to new project.
МҰНАЙШЫ Маусым 2013 53
Operators work according to a shift schedule. After the manner of the Kazakh proverb “the early bird catches the worm”, I get up at 5.30 am and start getting ready for work. A bus takes the workers from the hostel to the production site, and by 6:45 I am at work and ready to take over the shift. The main objective of our site is to treat crude oil and ensure it reaches commercial standards. We receive oil by pipeline and road tankers from the Kumkol, Kyzylkiya and Aryskum oil fields, and also from a number of other fields. We remove mechanical impurities, water, salt and oil gas, after which we transfer the commercial oil to KazTransOil pipeline system for further pumping according to the route through OQMS (Oil Quality Measuring System). Crude oil goes through a number of treatment processes and stages before it reaches a commercial standard. My role is to control as well the addition of chemical reagents that are used to ensure the swift removal of various impurities from the oil. I am also responsible for ensuring that facilities operate continuously.
We cannot afford to be ignorant, irresponsible or careless. We absolutely have to follow all safety and fire requirements. Although it was told a number of times, I will still stress again, with experience as a person who’s been working in the dangerous oil production industry and its heightened explosion risk for a long time, that negligence can threaten life and lead to significant damage.
3. What good habits have you acquired thanks to your work? I always follow safety regulations and all emergency prevention procedures closely. I am used to following the rules, which helps me discover any weaknesses and adopt the required measures. 4. What is your main personal achievement? It’s work related. In 1991, I started as a 3 rd
th
category operator. I was also honoured to receive a letter of gratitude from the Oblast Akim and a certificate of merit from the PKKR President.
Even though it may sound banal, I like spending time with my family, even more so as I work on rotation and I don’t get to see my wife and children that often. We enjoy spending time in the countryside, fishing on the local lake. If you think about it, it’s great just to see their smiling faces as they forget about the fuss of daily life.
6. What is your favourite saying or quotation? There’s a famous Kazakh proverb along the lines of “a Kazakh man is no longer a man if he doesn’t keep his word”. You could say that this sums me up.
It’s my understanding that the modern man needs to be strong spiritually, decent, patriotic and proud of his home country. A real man is one who’s remembered by his actions and not his words. In honor of Defender of Motherland Day we had interviews with our fellow employees about their job and not only. 7 QUESTIONS TO... ...GABIT YELMURATOV, 5 th category operator of dehydration and desalting unit, Central Processing Facility, Kumkol, PKKR Education Kyzylorda secondary technical vocational school №1, qualification - 3
rd category oil and gas production operator; Korkyt Ata Kyzylorda State University, speciality - oil and gas industry
1986 - worker, Pervomai karakul state farm; 1990 - 1 st category mechanic at section 11 of the Western Kazakhstan railway; 1991 - 3 rd category operator of dehydration and desalting unit (DDU), Yuzhneftegas; 2000 - 4 th category operator, DDU; 2007 - 5 th category operator, DDU, PKKR Awards - Letter of gratitude from the Kyzylorda Oblast Akim (2002) - Jubilee medal “Құмкөл кенішінің өнеркәсіптік игерілуінің 20 жылдығы” (2006)
- Letter of gratitude from the Company President (2011) Military Service Military rank - private, interior troops 54 Маусым 2013 МҰНАЙШЫ ...ADILBEK BEKLIYEV, Chief technician, PKKR 1. How have you changed while working in PetroKazakhstan? I started working for PetroKazakhstan immediately after finishing university, and have been working here for more than 20 years. I remember that in the 90’s, the oil industry was something new and a bit unusual for Kyzylorda. Rotation work, when you live a long way from your family, group rigs, collectors, specialised machinery and wells... And of course, oil - our black gold... It was all very interesting! When the summer came along with the scorching Kyzylorda sun, we forgot about the harsh winter, the cold and the wind, but we did want it to be a little bit cooler. Despite the fickleness of the weather and all the difficulties, we worked together well, were proud of our work and helped each other. It was, after all, the first field in Kazakhstan that local specialists instead of ones from neighbouring countries had developed. Working at Kumkol I have tried to understand the entire technical process and gain experience as I go. As a result, I have moved up the career ladder. Working for PetroKazakhstan has given me a lot: invaluable experience, organisational skills, an ability to be diplomatic and manage.
2. What qualities do you need in your profession? You need endurance. Working at an oil field requires stamina and patience, skilfulness, cold-bloodedness and strength. All of these qualities make a real oil man; someone who understands that it’s hard work that can help you reach those levels to ensure the Kyzylorda region and Kazakhstan as a whole flourishing.
In 2010, I was appointed as a chief engineer at Kolzhan LLP, and since 2011, I have been the chief technician at PKKR. When I used to work on the fields, I would really use my well-earned 15 rest days, if I had to, managing the field from the town. Today, I can’t really say which part of my working day is the quietest. A technical engineer’s work is never the same. Probably, the quietest part of the day is actually those couple of minutes in the morning just when you walk into your office (laughs). жүктеу/скачать 6,66 Mb. Достарыңызбен бөлісу:
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