THE ROLE OF DIFFERENT RHEOLOGICAL MODELS IN ACCURACY OF PRESSURE LOSS PREDICTION
Item
Title (Dublin Core)
eng
THE ROLE OF DIFFERENT RHEOLOGICAL MODELS IN ACCURACY OF PRESSURE LOSS PREDICTION
hrv
ULOGA RAZLIČITIH REOLOŠKIH MODELA U PRECIZNOM PREDVIĐANJU SMANJENJA TLAKA
Description (Dublin Core)
eng
Hydraulics play an important function in many oil field operations including drilling, completion, fracturing, acidizing, workover and production. The standard API methods for drilling fluid hydraulics assume either power law or Bingham plastic rheological model. These models and corresponding hydraulic calculations do provide a simple way for fair estimates of hydraulics for conventional vertical wells using simple drilling fluids, such as bentonite fluids. However, nowdays with many wells drilled deep, slim or horizontal using complex muds with unusual behaviour (such as tested MMH mud), it is necessary to use appropriate rheological model for mathematical modelling of fluid behaviour. Oil and gas reservoirs in Croatia have been under production for quite a while and the probability to discover new deposits of hydrocarbons is rather small. Therefore attempts have been made to maintain the gas and oil exploitation at the present level. One of possible ways to meet this target is re-entry wells drilling. The diameter of such wells in reservoir is smaller than 0,1524 m (6 in). Accurate modelling of annular pressure losses becomes therefore an important issue, particularly in cases where a small safety margin exists between optimal drilling parameters and wellbore stability, what is the case in re-entry wells. The objective of the paper is to show the influence of well geometry and accuracy of fluid rheological properties modelling to the distribution of pressure losses in a slimhole well.
hrv
Hidraulika ima vrlo važnu ulogu pri izvođenju velikog broja postupaka u bušotini uključujući bušenje, opremanje, frakturiranje, kiselinske obrade, održavanje i proizvodnju. Razmatranje hidraulike bušaćeg fluida prema API postupcima podrazumijeva primjenu ili eksponencijalnog ili Bingham plastičnog reološkog modela. Ti modeli i odgovarajući proračuni hidraulike osiguravaju jednostavan način dobivanja podataka prihvatljve točnosti za slučaj primjene u konvencionalnim vertikalnim bušotinama i kod primjene bušotinskih fluida jednostavnog sastava, kao što su bentonitne isplake. Međutim, danas, kada se izrađuje veliki broj dubokih bušotina, bušotina velikog dosega ili malog promjera, koje mogu biti usmjerene ili horizontalne, a za njihovu izradu koriste se fluidi složenog sastava i neobičnog ponašanja (kao što je slučaj s ispitanom MMH isplakom), neophodno je za modeliranje ponašanja fluida primijeniti odgovarajući reološki model. Budući se iz postojećih ležišta u Hrvatskoj nafta i plin proizvode već dulje vrijeme, a vjerojatnost otkrivanja novih ležišta je mala, nastoji se zadržati proizvodnju nafte i plina na današnjoj razini. Jedan od mogućih načina da se to ostvari je i izrada bočnih ("re-entry") bušotina. Promjer takve bušotine unutar ležišta najčešće je manji od 0,1524 m (6 in). U takvim slučajevima vrlo je važno precizno modeliranje smanjenja tlaka u prstenastom prostoru. Posebno se to odnosi na slučajeve gdje postoji mali sigurnosni zazor između postizanja optimalnih bušaćih parametara i kanala bušotine, kao što je to slučaj kod izrade bočnih bušotina. U radu je prikazan utjecaj geometrije bušotine i preciznosti modeliranja reoloških svojstava fluida na smanjenje tlaka u kanalu bušotine malog promjera.
Creator (Dublin Core)
SIMON, KATARINA
Subject (Dublin Core)
eng
slimhole drilling;hydraulics;rheological model;drill-in fluid
hrv
izrada bušotina malog promjera;hidraulika;reološki model;drill-in fluid
Publisher (Dublin Core)
Faculty of Mining, Geology and Petroleum Engineering University of Zagreb
Date (Dublin Core)
2004
Type (Dublin Core)
text
info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
https://hrcak.srce.hr/13370
eng
https://hrcak.srce.hr/file/20491
Source (Dublin Core)
Rudarsko-geološko-naftni zbornik
ISSN 1849-0409 (Online)
Volume 16
Issue 1
Language (Dublin Core)
eng
Rights (Dublin Core)
info:eu-repo/semantics/openAccess
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All volumes of the Bulletin (from 1989) are available at Hrčak journal pages (http://hrcak.srce.hr/rgn-zbornik?lang=en).
The Bulletin is open access (OA, green model, CC-BY) journal what means that electronic versions of articles are accessible to readers, without any fees or registration.When use, please refer to Creative Commons license (BY type, http://creativecommons.org/licenses/by/4.0/ ).
Publisher copyright policies & self-archiving is also described at Sherpa organisation web (RoMEO service) based at the University of Nottingham (http://www.sherpa.ac.uk/romeo/pub/2374/).
All volumes of the Bulletin (from 1989) are available at Hrčak journal pages (http://hrcak.srce.hr/rgn-zbornik?lang=en).