Elimination of complications occurred by hydrodynamic pressure during running casing

2021 ◽  
pp. 20-22
Author(s):  
J.S. Akhundov ◽  

The elimination of complications occurred due to the hydrodynamic pressure at the wellbore during the running of the casing is one of the hardest tasks. During the well drilling in geologically complicated fields using drilling mud with 1800–2000 kg/m3 density, hydraulic fracture of the reservoir takes places while running of the casing due to the hydrodynamic pressure at the wellbore. This, in its turn, leads to the intensive drilling mud loss. To prevent such cases, it is necessary to have ra<0.65 coefficienct in well structure selection. This rate is the relation of well outer diameter to the wellbore diameter.

2019 ◽  
Vol 12 ◽  
pp. 107-111
Author(s):  
A.N. Ivanov ◽  
◽  
O.V. Kryukov ◽  
Vu Van Hung ◽  
Mai Duy Khanh ◽  
...  
Keyword(s):  

2021 ◽  
Vol 66 (05) ◽  
pp. 192-195
Author(s):  
Rövşən Azər oğlu İsmayılov ◽  

The aricle is about the pipe stick problems of deep well drilling. Pipe stick problem is one of the drilling problems. There are two types of pipe stick problems exist. One of them is differential pressure pipe sticking. Another one of them is mechanical pipe sticking. There are a lot of reasons for pipe stick problems. Indigators of differential pressure sticking are increase in torque and drug forces, inability to reciprocate drill string and uninterrupted drilling fluid circulation. Key words: pipe stick, mecanical pipe stick,difference of pressure, drill pipe, drilling mud, bottomhole pressure, formation pressure


2021 ◽  
Author(s):  
Chee Phuat Tan ◽  
Wan Nur Safawati Wan Mohd Zainudin ◽  
M Solehuddin Razak ◽  
Siti Shahara Zakaria ◽  
Thanavathy Patma Nesan ◽  
...  

Abstract Drilling in permeable formations, especially depleted reservoirs, can particularly benefit from simultaneous wellbore shielding and strengthening functionalities of drilling mud compounds. The ability to generate simultaneous wellbore shielding and strengthening in reservoirs has potential to widen stable mud weight windows to drill such reservoirs without the need to switch from wellbore strengthening compound to wellbore shielding compound, and vice-versa. Wellbore shielding and strengthening experiments were conducted on three outcrop sandstones with three mud compounds. The wellbore shielding stage was conducted by increasing the confining and borehole pressures in 4-5 steps until both reached target pressures. CT scan images demonstrate consistency of the filtration rates with observed CT scanned mud cakes which are dependent on the sandstone pore size and mud compound particle size distributions. In wellbore strengthening stage, the borehole pressure was increased until fracture was initiated, which was detected via borehole pressure trend and CT scan imaging. The fractures generated were observed to be plugged by mud filter solids which are visible in the CT scan images. The extent of observed fracture solid plugging varies with rock elastic properties, fracture width and mud compound particle size distribution. Based on the laboratory test data, fracture gradient enhancement concept was developed for the mud compounds. In addition, the data obtained and observations from the tests were used to develop optimal empirical design criteria and guidelines to achieve dual wellbore strengthening and shielding performance of the mud compounds. The design criteria were validated on a well which was treated with one of the mud compounds based on its mud loss events during drilling and running casing.


Author(s):  
Marcio Yamamoto ◽  
Motohiko Murai ◽  
Shotaro Uto ◽  
Tomo Fujiwara ◽  
Shigeo Kanada ◽  
...  

The pipes are playing an important role in the offshore environment. Risers and pipelines are widely deployed by the petroleum industry for the well drilling and hydrocarbons production. Whereas during drilling, a mixture of drilling mud and solids in suspension (rock cuttings) flows through the drilling riser; during the production, mono or multiphase flow (comprising oil, water and gas) takes place within the production system. However up till now, most of investigations on offshore pipelines and risers have neglected the effects of the internal flow and have focused mainly on the interaction among pipe’s structure, hydro-dynamic forces and offshore platform’s motion. This paper deals with the interaction between the pipe structure and its internal flow. An experimental analysis was carried out, in the Deep Sea Basin of the National Maritime Research Institute (Japan), using a model of 10 m length. In this experiment, a mono-phase fluid of liquid and another bi-phase fluid of liquid and solids in suspension are used as the internal flow fluid and a parametric analysis using the internal flow rate and pipe’s oscillating frequency was carried out. Discussion about the experimental results is also included.


Author(s):  
Marcio Yamamoto ◽  
Motohiko Murai ◽  
Katsuya Maeda ◽  
Shotaro Uto

Nowadays pipes are widely deployed in the offshore environment especially in the petroleum industry where rigid and flexible pipes are used for well drilling and hydrocarbon production. Whereas during drilling, a mixture of drilling mud, rock cuttings and sometimes gas flows through the drilling riser, during production mono or multiphase (comprising oil, water and gas) flow takes place within the system. However up till now, most of the studies on offshore pipelines and risers have been focused on the pipe structure and its interaction with hydrodynamic forces and offshore platforms. In particular for numerical computation studies and reduced scale model experiments, the pipe is usually modeled as a tensioned beam and sometimes only the internal pressure is taken into account with other effects due to its internal flow being neglected. This paper deals with the interaction between the pipe structure and its internal flow. In order to verify the internal flow effects, an experimental analysis was carried out not using a reduced scale model. In particular, mono-phase fluid flows into the pipe and a parametric analysis using the flow rate was carried out. Discussion about the experimental results and numerical applications is also included.


2020 ◽  
pp. 26-29
Author(s):  
T.Sh. Salavatov ◽  
◽  
Y.I. Safarov ◽  
S.A. Musayeva ◽  
◽  
...  

The paper makes an effort to specify the relaxation time of subsurface rocks composing the borehole wall during geothermal well drilling justifying theoretical and practical researches. To solve mentioned issues, a theory of dumping of pressure fluctuations in non-stationary motion of drilling mud in the circulation system of well, based on the data of change of pressure and time consumption is applied and as a result a calculation formula obtained. The method has been tested in the well No 245 in Muradkhanly area.


2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Chinedum Peter Ezeakacha ◽  
Saeed Salehi

Drilling mud loss in highly porous media and fractured formations has been one of the industry's focuses in the past decades. Wellbore dynamics and lithology complexities continue to push for more research into accurate quantification and mitigation strategies for lost circulation and mud filtration. Conventional methods of characterizing mud loss with filtration data for field application can be time-consuming, particularly because of the interaction between several factors that impact mud loss and filtration. This paper presents a holistic engineering approach for characterizing lost circulation using pore-scale dynamic water-based mud (WBM) filtration data. The approaches used in this study include: factorial design of experiment (DoE), hypothesis testing, analysis of variance (ANOVA), and multiple regression analysis. The results show that an increase in temperature and rotary speed can increase dynamic mud filtration significantly. An increase in lost circulation material (LCM) concentration showed a significant decrease dynamic mud filtration. A combination of LCM concentration and rotary speed showed a significant decrease in dynamic mud filtration, while a combination of LCM concentration and temperature revealed a significant increase in dynamic mud filtration. Rotary speed and temperature combination showed an increase in dynamic mud filtration. The combined effect of these three factors was not significant in increasing or decreasing dynamic mud filtration. For the experimental conditions in this study, the regression analysis for one of the rocks showed that dynamic mud filtration can be predicted from changes in LCM concentration and rotary speed. The results and approach from this study can provide reliable information for drilling fluids design and selecting operating conditions for field application.


SPE Journal ◽  
2017 ◽  
Vol 22 (04) ◽  
pp. 1201-1212 ◽  
Author(s):  
Ben Li ◽  
Hui Li ◽  
Boyun Guo ◽  
Xiao Cai ◽  
Mas lwan Konggidinata

Summary Gas-hydrate cuttings are conveyed upward by the drilling fluid through the outer drillpipe/wellbore annulus during the gas-hydrate-well-drilling process. The temperature profile along the wellbore during the drilling process has not been thoroughly investigated because the gas-hydrate cuttings could affect the temperature of the drilling fluid along the wellbore. As the mixture of drilling fluid and gas hydrates flows from the bottom to the surface, the methane and other hydrocarbons present in the gas hydrates would change from liquid to gas phase and further cause well-control issues. Furthermore, the bottomhole pressure would decrease and could not provide sufficient balance to the formation pressure, which could significantly increase the risk of well blowout. A numerical solution is presented in this paper to predict the temperature profile of the gas-hydrate well during the drilling process. The main considerations were the following: Hydrate cuttings entrained in the bottom of the hole would affect the temperature of the fluid in the annulus space. The entrained hydrate cuttings could affect the fluid thermal properties in the drillstring and in the annulus. Because of the Joule-Thomson cooling effect at the outlet of the nozzles, the fluid temperature at the bottom of the hole was lower than that above the drill-bit nozzles. Hence, the gas-hydrate-dissociation characteristics were considered and integrated in the proposed numerical model. The numerical model was validated by comparing the obtained data with the Shan et al. (2016) analytical model. In addition, the obtained data were also compared with the measured temperature data of a conventional well drilled in China and a gas-hydrate-well drilling record in India. Sensitivity analysis was used to evaluate the effects of the pumping rate, Joule-Thomson effect, and injection drilling-mud temperature on the annulus temperature-profile distribution. It was found that the injection drilling-mud temperature and pumping rate could affect the temperature profile in the annulus, whereas the Joule-Thomson effect could decrease the annulus temperature of the drilling mud near the bottom.


2019 ◽  
Vol 9 (1) ◽  
pp. 3859-3862 ◽  
Author(s):  
R. Iqbal ◽  
M. Zubair ◽  
F. Pirzada ◽  
F. N. Abro ◽  
M. Ali ◽  
...  

Drilling mud density is an important factor in drilling operations. The cost of the drilling mud used for oil and gas well drilling can be 10%-15% of the total drilling cost, and the deeper the well, the more the needed drilling mud. This research aims to prepare a mud that provides performance similar to the conventional mud and to lower down the dependency of primitive CaCO3 technology by exploring it from trash/polluted and naturally occurring materials. For that purpose, a mud was prepared by replacing primeval CaCO3 with the CaCO3 derived from eggshells, as eggshells contain CaCO3 in high amounts which range from 70% to 95%. The success of this project will provide an affordable solution and an alternative way to explore new methodologies for obtaining CaCO3. According to the 2017 Report of Pakistan Poultry Association (PPA) 18,000 Million table eggs are consumed per year in Pakistan. The obtained results of this research are quite satisfactory. CaCO3 obtained from eggshells is used in high amounts, 275–410g to achieve density ranges from 9.5 to 11.0 pounds per gallon whereas, pure the needed quantity of pure CaCO3 is 150g to obtain the density of 10.5 pounds per gallon. Apart from this, it is also observed that eggshell based CaCO3 samples are more efficient in rheological properties compared to the market samples of CaCO3 t. The pH of pure CaCO3 sample of 10.5 pounds per gallon density is almost the same with the sample of eggshell CaCO3 of 10.5 pounds per gallon density.


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