The Experts below are selected from a list of 333 Experts worldwide ranked by ideXlab platform
Røsbak André - One of the best experts on this subject based on the ideXlab platform.
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Calculation of forces acting on a rotary steerable liner drilling system
University of Stavanger Norway, 2009Co-Authors: Røsbak AndréAbstract:Torque and drag calculations performed on a new liner drilling design indicate that a very high grade Drillpipe, up to S-135, is required in order to satisfy the requirements which both axial and torsional loading place upon the system. High torque connections for the Drillpipe may also be required. The torque values found both with simulations and manual calculations, indicate that the proposed standard VAM TOP liner connections may not be strong enough to be used in this well. It is therefore recommended that VAM HTF, or similar high torque liner connections, are used in order to meet torsional loading requirements. The use of 6 5/8” Drillpipe and 5 ½” Drillpipe above the top of the liner is also considered. Based on the calculated recommended flow rates with regards to hole cleaning for the two systems, compared with the resulting ECD values, it is suggested that 6 5/8” Drillpipe provides a better compromise between hole cleaning and ECD values. Simulations indicate that the Drillpipe connections are strong enough, while manual calculations indicate that hightorque Drillpipe connections should be considered. The lifting force caused by the circulation of fluid is examined, but is not found to be of significant magnitude compared to the mechanical friction. It is important to examine this force, in order to determine whether or not the system will have problems related to buckling, although it does not appear to present a problem in this case. A general approach which can be used in order to determine the fatigue loading and longevity of the liner connections is shown. However, since the actual data for the liner connections are kept confidential by the manufacturer, no specific recommendations are made. It should be noted that the conclusions of this thesis are valid for the wellpath and well conditions presented in this thesis only, and that different wellpaths and well conditions may impose other limits, either more or less stringent, on the design and use of the steerable liner drilling system
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Calculation of forces acting on a rotary steerable liner drilling system
University of Stavanger Norway, 2009Co-Authors: Røsbak AndréAbstract:Master's thesis in Petroleum engineeringTorque and drag calculations performed on a new liner drilling design indicate that a very high grade Drillpipe, up to S-135, is required in order to satisfy the requirements which both axial and torsional loading place upon the system. High torque connections for the Drillpipe may also be required. The torque values found both with simulations and manual calculations, indicate that the proposed standard VAM TOP liner connections may not be strong enough to be used in this well. It is therefore recommended that VAM HTF, or similar high torque liner connections, are used in order to meet torsional loading requirements. The use of 6 5/8” Drillpipe and 5 ½” Drillpipe above the top of the liner is also considered. Based on the calculated recommended flow rates with regards to hole cleaning for the two systems, compared with the resulting ECD values, it is suggested that 6 5/8” Drillpipe provides a better compromise between hole cleaning and ECD values. Simulations indicate that the Drillpipe connections are strong enough, while manual calculations indicate that hightorque Drillpipe connections should be considered. The lifting force caused by the circulation of fluid is examined, but is not found to be of significant magnitude compared to the mechanical friction. It is important to examine this force, in order to determine whether or not the system will have problems related to buckling, although it does not appear to present a problem in this case. A general approach which can be used in order to determine the fatigue loading and longevity of the liner connections is shown. However, since the actual data for the liner connections are kept confidential by the manufacturer, no specific recommendations are made. It should be noted that the conclusions of this thesis are valid for the wellpath and well conditions presented in this thesis only, and that different wellpaths and well conditions may impose other limits, either more or less stringent, on the design and use of the steerable liner drilling system
Richard P Gensme - One of the best experts on this subject based on the ideXlab platform.
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field correlation between internal taper length and tube failures in 4 5 in 16 60e ieu Drillpipe
Spe Drilling Engineering, 1990Co-Authors: Richard P GensmeAbstract:Noble Drilling Corp. has become increasingly concerned with premature failures in 4.5-in. (11.4-cm), 16.60 Grade E, IEU Drillpipe tubes that meet industry requirements for metal structure, hardness, strength, and chemical composition and that show no signs of physical abuse. The authors' study of the pipe structure showed that a high percentage of tube failures were in tubes with short internal taper lengths. The authors examined a string of Drillpipe with 18 tube cracks in the first 2,800 rotating hours in an area where 13,000 to 18,000 hours is a common life expectancy and studied drillstrings produced by three other manufacturers. The authors found that 80% of our failures occur within 10 to 12 in. (25 to 30 cm) of the internal taper, that the taper lengths are shorter among the failed joints than among a general population of Drillpipe, and that these short taper lengths are not common to just one manufacturer or nation.
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field correlation between internal taper length and tube failures in 4 5 in 16 60e ieu Drillpipe
Drilling conference, 1990Co-Authors: Richard P GensmeAbstract:Noble Drilling Corp. s'est attaquee a l'etude des causes des defauts apparaissant prematurement sur les tubes de forage de type 16.60 Grade E IEU. L'etude a montre que la frequence des defauts etait liee a la longueur du retrecissement interne. Il semble indispensable de mettre rapidement au point une methode de choix du materiel reposant sur ce facteur.
Musaed N J Alawad - One of the best experts on this subject based on the ideXlab platform.
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prediction of critical pipe running speed during tripping in drilling operations
Journal of King Saud University: Engineering Sciences, 1999Co-Authors: Musaed N J AlawadAbstract:Abstract Blowout and loss of circulation are two serious accidents that can happen while drilling without the control on drillstring running speed during tripping operations. Exceeding the critical running speed during tripping-out (high swabbing pressure) and lack of control of mud rheology are the main causes for blowout. Also, exceeding the critical running speed while tripping-in (high surge pressure) and lack of control of mud rheology are the main causes for loss of circulation. Many factors which affect surge and swab pressures must be precisely selected in order to control kicks or blowouts and to prevent loss of circulation. Prediction of the critical pipe running-in and -out speeds during tripping operations is therefore very important. This can be done by the evaluation of several basic fluid flow equations. A computer program has been developed to simplify these calculations. The developed program requires fairly simple input data which can be measured in laboratory in addition to hole and drillstring dimensions. The output of this program then is transformed into graphical form from which the safe running-in and -out speeds during tripping can be predicted. As an alternative and direct way to predict the critical pipe running speed during tripping operations two correlations have been developed. These correlations account for the governing factors which affect the tripping-in and -out speeds including mud properties and drillstring and hole configuration. A comparison between the critical pipe running speed computed using the two methods has been outlined and very good accuracy based on the coefficient of linear correlation (r2) and the standard error of estimate (SEE) (r2 = 0.995 ; SEE = 0.39 for running-out correlation and r2 = 0.875 ; SEE = 0.817 for running-in correlation) have been obtained. Critical tripping speeds were found to be greatly dependent on mud weight and rheology, hole diameter and drillcollars-to-Drillpipe length ratio.
Thingbø, Kjersti Selstad - One of the best experts on this subject based on the ideXlab platform.
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Optimalisering av hydraulisk program for boringmed liner
Norges teknisk-naturvitenskapelige universitet Fakultet for ingeniørvitenskap og teknologi Institutt for petroleumsteknologi og anvendt geofysikk, 2011Co-Authors: Thingbø, Kjersti SelstadAbstract:Drilling with casing and liner are unconventional drilling methods developed to reduce both the non-productive time spent on drilling operations and drilling time in general. A casing or liner string is used as the drillstring, and the number of operations is therefore reduced from two to one as drilling and casing of the wellbore are performed in one operation. Even though there are many benefits with this drilling method, there are also some drawbacks and operational considerations. Statoil and Baker Hughes have developed a rotary steerable liner drilling system, called the Steerable Drilling Liner (SDL). Two offshore test wells have been drilled with this system, and Statoil is now planning to utilize it on more wells in the North Sea. The Oseberg field is a candidate field for liner drilling due to stability problems in the Draupne and Ness formations. Two wells on the Oseberg field have therefore been chosen as the candidate wells for this thesis.The case histories of the test wells show that the limitation may be the low flow rate circulated through the liner, which may cause cuttings accumulation on top of the liner where the flow area suddenly expands. A flow diverter is therefore developed to have more flexibility in the choice of flow rate above the liner. The flow diverter and other solutions to improve the hole cleaning have been evaluated in this thesis. The high annular circulating pressure is another issue with the liner drilling technique. Many of the factors which improve hole cleaning also increase the annular pressure. The ECD must also be taken into consideration when optimizing the hole cleaning of the candidate wells. The simulations of hole cleaning and annular circulating pressure for the SDL system have been performed in WellPlan.The recommended flow rate for hole cleaning in the sections above the liner is at least 500 lpm higher than the maximum possible flow rate through the liner. By circulating this recommended rate through the liner, the equivalent circulating density increases. The circulating pressure exceeds the fracture pressure of the formation for the 7” SDL system. It is therefore not an alternative to come up with solutions to be able to circulate with a higher flow rate through the SDL system. A flow diverter above the liner is the best solution to increase the flow rate in the critical part of the well.With the flow diverter above the liner, the flow rate can be increased to the minimum required rate for hole cleaning and at the same time keep the equivalent circulating density at an acceptable level. The increased flow rate above the flow diverter will have minimal effect on the annular circulating pressure below the previous casing shoe.The simulations also showed that this minimum rate can be significantly reduced by changing the drilling fluid parameters. If the flow rate is kept constant, the bed height of cuttings can be reduced by optimizing the fluid parameters. Optimization of the drilling fluid is also important to make sure the cleaning in the annulus outside the liner is good. The required rate could be reduced further by increasing the rotation of the string and increasing the size of the Drillpipe above the liner, and these solutions have been evaluated.Future work should include the development of a simulation program that can include all the downhole tools and components required for the Steerable Drilling Liner system, including two flow split components. The simulation program should also be able to handle the combination of a pilot bottom hole assembly and an underreamer to ream the hole to full size, and then calculate the correct amount of cuttings in the annulus. The drilling fluids should also be optimized to improve the hole cleaning in liner drilling operations further.
Nguye Cuong - One of the best experts on this subject based on the ideXlab platform.
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A study of underbalanced drilling application for granite basements in Vietnam
'Heriot-Watt University', 2009Co-Authors: Nguye CuongAbstract:Underbalanced drilling (UBD) has gained popularity during the recent years as it provides a method to prevent formation damage, minimize lost circulation risks, and increase the rate of penetration. However, drilling with a bottomhole pressure less than the formation pore pressure will often increase the risk of borehole instability due to the shear or compression failure of the rock adjacent to the wellbore. The extent of rock failure is related directly to the pressure in the annulus between the Drillpipe, collars and the wellbore which can only be calculated through modelling multiphase flow in the drilling system. The relationship between rock failure and wellbore hydraulics becomes more complex due to the appearance of the influx formation fluid in UBD. Therefore, the aim of this research is to describe methods to solve the complex interaction of wellbore stability, rock yielding, collapse, wellbore hydraulics, and production capacity during UBD operations. To achieve the aim, analytical and numerical solutions have been codified into two programs WELLST, and UBDRILL. Commercial software packages such as ABAQUS, PERFORM, HYMOD were also used to model the process. Field data from granite basement reservoirs of Basin X, Vietnam were used as the parameters input into the model to calculate. This research includes: • An analysis of the influences of time dependence, thermal and hydraulic diffusivity, wellbore pressure changes, inclination and azimuth variation, poroelastic and thermo-poroelastic deformation, cooling and heating effects on wellbore stability in UBD. • An analysis of pressure, temperature, fluid properties distribution in the annulus and inside the Drillpipe while UBD. • An analysis of the suggested liquid gas rate window (LGRW) which gives field engineers flexibility in the selection of liquid and gas injection rates on the drilling site when UBD is applied. • An estimation of production capacity in UBD operations. These results were obtained by analyzing the field data of granite basement formations and clastic formations of Basin X, Vietnam which is under compression in a strike-slip environment
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A study of underbalanced drilling application for granite basements in Vietnam
2009Co-Authors: Nguye CuongAbstract:Underbalanced drilling (UBD) has gained popularity during the recent years as it provides a method to prevent formation damage, minimize lost circulation risks, and increase the rate of penetration. However, drilling with a bottomhole pressure less than the formation pore pressure will often increase the risk of borehole instability due to the shear or compression failure of the rock adjacent to the wellbore. The extent of rock failure is related directly to the pressure in the annulus between the Drillpipe, collars and the wellbore which can only be calculated through modelling multiphase flow in the drilling system. The relationship between rock failure and wellbore hydraulics becomes more complex due to the appearance of the influx formation fluid in UBD. Therefore, the aim of this research is to describe methods to solve the complex interaction of wellbore stability, rock yielding, collapse, wellbore hydraulics, and production capacity during UBD operations. To achieve the aim, analytical and numerical solutions have been codified into two programs WELLST, and UBDRILL. Commercial software packages such as ABAQUS, PERFORM, HYMOD were also used to model the process. Field data from granite basement reservoirs of Basin X, Vietnam were used as the parameters input into the model to calculate. This research includes: • An analysis of the influences of time dependence, thermal and hydraulic diffusivity, wellbore pressure changes, inclination and azimuth variation, poroelastic and thermo-poroelastic deformation, cooling and heating effects on wellbore stability in UBD. • An analysis of pressure, temperature, fluid properties distribution in the annulus and inside the Drillpipe while UBD. • An analysis of the suggested liquid gas rate window (LGRW) which gives field engineers flexibility in the selection of liquid and gas injection rates on the drilling site when UBD is applied. • An estimation of production capacity in UBD operations. These results were obtained by analyzing the field data of granite basement formations and clastic formations of Basin X, Vietnam which is under compression in a strike-slip environment.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
