-
Date submitted2022-03-24
-
Date accepted2022-07-21
-
Date published2022-12-29
A probabilistic study on hole cleaning optimization
- Authors:
- Seyyed Shahab Tabatabaee Moradi
Hole cleaning is considered as one of the most important drilling fluid functions. An efficient hole cleaning ensures a reliable well drilling practice with minimum troublesome problems. In this study, two main steps of hole cleaning, i.e., cuttings removal from under the bit and cuttings transport to the surface are discussed based on the drilling data of a shale formation. The traditional models for optimization of each step are presented. As the models require variety of input data, which are usually subjected to some extent of errors and uncertainties, the output of the model is also an uncertain parameter. Using Monte Carlo simulation, a simple probabilistic study was conducted to quantify the certainty level of the obtained results. Based on the result of this study, it is shown that for the proposed well, a good hole cleaning is expected. However, a more reliable decision for further hole cleaning optimization should be made considering the results of uncertainty analysis.
-
Date submitted2019-06-30
-
Date accepted2019-09-10
-
Date published2019-12-24
Industrial safety principles in coal mining
- Authors:
- E. N. Chemezov
The article provides a description of injuries in coal mining enterprises in Russia. The high injury rate causes the need of developing new effective ways and means of improving safety at mining enterprises. Recently in Russia there has been a tendency for a slight decrease in fatal injuries, which indicates some progress in prevention of industrial accidents. At the same time, the problem of improving the working conditions of coal miners, reducing the level of injuries and occupational diseases in this industry remains a very urgent task. Ensuring safe operation and industrial health and safety is not only reasonable economic policy but one of the constitutional human rights. At Russian coal mining enterprises, they take measures to reduce injuries, the supervisory authorities and employees of the enterprises carry out certain work to comply with safety requirements. However, significant success has not yet been achieved. Despite the fatal injuries and accidents, the issue of industrial mining safety is not becoming a top priority. Occupational safety measures are often financed on a «left-over» principle, and therefore remain not implemented. Many managers do not pay enough attention to safety issues and have little control over the planned activities in this area. The article analyzes the causes of injuries and proposes the key directions for creating normal working conditions in coal mining enterprises.
-
Date submitted2017-10-29
-
Date accepted2017-12-31
-
Date published2018-04-24
Risk assessment of accidents due to natural factors at the Pascuales – Cuenca multiple-use pipeline (Ecuador)
- Authors:
- Dzh. Zambrano
- S. V. Kovshov
- E. A. Lyubin
The natural aspects of the accident risk at the Pascuales – Cuenca multiple-use pipeline (Ecuador) are analysed in the paper. The Russian Methodological recommendations for the quantitative analysis of accident risks at hazardous production plants of oil trunk pipelines and oil product trunk pipelines issued in 2016 are used as a methodological framework due to relatively poorly defined evaluation mechanism for natural factors of accidents at oil trunk pipelines in the most widespread international accident risk assessment methodologies. The methodological recommendations were updated to meet the environmental conditions of oil pipelines of Latin America. It was found that the accidents due to natural factors make up approximately 15 % of cases at oil trunk pipelines in Ecuador. Natural geographical features of the areas surrounding the main Ecuadorian Pascuales–Cuenca oil trunk pipeline and its relatively short length allow defining three zones along the line in terms of the accident risk: lowland coastlines, high plateaus, and foothills. Calculations and analysis revealed that the maximum predicted specific frequency of accidents is characteristic of the lowland seaside area. The evidence showed that physical and chemical properties of soils and significant seismic activity are the root causes of failures.
-
Date submitted2009-10-18
-
Date accepted2009-12-05
-
Date published2010-09-22
Assessment of the role of geodynamic factor in the accident rate of pipeline systems
- Authors:
- E. K. Melnikov
- A. N. Shabarov
The authors relate to the geodynamically active faults those faults with continuous up to present time low-amplitude movements which lead to the destructurization both of bedding rocks and of Quarternary deposits. The electrogeochemical processes proceeding in the zones of such faults, promote the metal corrosion that basically is the cause of increasing a few tens of times of specific accident rate at sites of active faults crossing with pipelines.