Drilling operations in the Halfaya oilfield frequently encounter severe wellbore instability challenges. When navigating shale deposits, wellbore instability remains the primary operational concern. Based on the analysis of the wellbore instability intervals, low-strength shale and marlstone formations are identified as the principal unstable zones that lead to non-productive time and higher drilling costs. By planning a safe operating mud window, these non-productive times and drilling costs can be mitigated. Several wellbore instability concerns have been found in a southern Iraqi oil field. A problem-diagnostic technique was done by evaluating well log data, drilling reports, mud logging reports, and pore pressure readings. In wellbore stability evaluations, the three rock failure criteria that are used the majority of the time are the Mohr-Coulomb, Mogi-Coulomb and Modified Lade criterion were used to predict a safe mud weight window. The Mogi-Coulomb and Modified Lade criteria provided more accurate predictions than the Mohr-Coulomb model in well H1. The Mohr-Coulomb criterion proved inadequate for this formation because it fails to account for the intermediate principal stress. According to the pore pressure predictions in this study, the unsuitable mud weight of 10.49 ppg is the major cause of wellbore instability during the drilling of the Nahr Umr A formation in this well; therefore, a mud weight of 14.5–15 ppg is recommended. The Formation Micro Imager (FMI) was responsible for determining the orientations of the horizontal stresses. The Halfaya oilfield has an azimuth that corresponds to a maximum horizontal stress of about N20–35 E, the findings indicate that the Nahr Umr formation is characterized by a reversal faulting regime > > . Formation lithology impacts Halfaya oilfield horizontal stress. High-strength, hardened intervals have high horizontal stress, shale and marlstone formations with low strength are the principal unstable wellbore intervals. Ultimately, to prevent breakout failures and minimize drilling fluid losses, it is recommended to either restrict wellbore inclination or employ an optimized, higher mud weight.
In this paper, the effect of wear in the fluid film journal bearings on the dynamic stability of rotor bearing system has been studied depending on the development of new analytical equations for motion, instability threshold speed and steady state harmonic response for rotor with offset disc supported by worn journal bearings. Finite element method had been used for modeling the rotor bearing system. The analytical model is verified by comparing its results with that obtained numerically for a rotor supported on the short bearings. The analytical and numerical results showed good agreement with about 8.5% percentage error in the value of critical speed and about 3.5% percentage error in the value of harmonic response. T
... Show MoreA common field development task is the object of the present research by specifying the best location of new horizontal re-entry wells within AB unit of South Rumaila Oil Field. One of the key parameters in the success of a new well is the well location in the reservoir, especially when there are several wells are planned to be drilled from the existing wells. This paper demonstrates an application of neural network with reservoir simulation technique as decision tool. A fully trained predictive artificial feed forward neural network (FFNNW) with efficient selection of horizontal re-entry wells location in AB unit has been carried out with maintaining a reasonable accuracy. Sets of available input data were collected from the exploited g
... Show MoreThis paper presents a study of the application of gas lift (GL) to improve oil production in a Middle East field. The field has been experiencing a rapid decline in production due to a drop in reservoir pressure. GL is a widely used artificial lift technique that can be used to increase oil production by reducing the hydrostatic pressure in the wellbore. The study used a full field model to simulate the effects of GL on production. The model was run under different production scenarios, including different water cut and reservoir pressure values. The results showed that GL can significantly increase oil production under all scenarios. The study also found that most wells in the field will soon be closed due to high water cuts. Howev
... Show MoreBeen using a pv system program to determine the solar window for Baghdad city . the solar window for any location can be determine by deviating left and right from the geographical south as well as deviation according to the amount of tilt angle with the horizon for fixed panel so that will not change the average of solar radiation incident over the whole year and this lead to help in the process of installation of fixed solar panel without any effect on annual output .the range of solar window for Baghdad city between two angles ( -8 - +8 ) degrees left to right of the geographical south and tilt angle that allowed for the horizon range between angles (21- 30) degrees so that the amount of solar radiation that falling on the solar pan
... Show MoreThe regular job of a reservoir engineer is to put a development plan to increase hydrocarbon production as possible and within economic and technical considerations. The development strategy for the giant reservoir is a complex and challenging task through the decision-making analysis process. Due to the limited surface water treatment facility, the reservoir management team focuses on minimizing water cut as low as possible by check the flow of formation and injected water movement through the Mishrif reservoir. In this research, a representative sector was used to make the review of water injection configuration, which is considered an efficient tool to make study in a particular area of the entire field when compared with the ful
... Show MoreBackground: Neonatal Septicemia (NNS) is generalized microbial symptomatic infection during the first 28 days of life.It>s the most serious complication in Neonatal Intensive Care Units (NICU) that demand urgent diagnosis and accurate treatment.Objective: To reveal the relationship of neonatal septicemia with birth weight (one of the neonatal risk factors).Patients and Methods: Blood sample was obtained from 76 neonates aged 1 hour-28 days who were diagnosed clinically (poor feeding, respiratory distress, fever, hypothermia, gastrointestinal and/or central nervous system symptoms)and bacteriologically to have neonatal septicemia.Results:One of the most important neonatal factor predisposing to infection is low birth weight, signi
... Show MoreThis thesis study (pen weight and diversity of Arabic calligraphy), including the Arabic script went through multiple bodies, it came through the natural evolution of societies, and helped in the renovation and development of calligraphy after they gained a clear identity as a result of development that has occurred in the materials and writing instruments, especially industry pen that led to the diversity of Arabic calligraphy, and through the exploratory research and modeling study, which was obtained that the researcher could pose a problem discussed in the first chapter of his study follows by asking: is the pen is the weight of the role in the diversity of Arabic calligrap
... Show MoreSince the beginning of 21st century, the prices of Agricultural crops have increased. This Increases is accompanied with that increases of crude oil prices and fluctuation of a dollar exchange rate as a dominant currency used in the global trade. The paper aimed to analysis the short run and long run cointegration relationships between prices of some of Agricultural crops imported by Iraq such as wheat and rice crops and both the crude oil prices and the Iraq dinar exchange rate a gained America dollar using ARDL model. The results show the long run equilibrium between they three variable throng the error correction mechanizem. The results also show the significant and economically sound effects of cru
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