scholarly journals Selection of automatic vertical drilling system for the fourth section in Shunbei 11 well, Tarim basin, China

2021 ◽  
Vol 303 ◽  
pp. 01045
Author(s):  
Weiqiang Song ◽  
Shaojie Chen ◽  
Weiguang Sun ◽  
Junming Zhang ◽  
Hongjian Ni

Based on the introduction of the working principles of various automatic vertical drilling systems (VDS), the latter are divided into rotary push type and sliding push type. Then the technical advantages and applicable scope of various types of drilling tools are analysed. Combined with the latest domestic application progress and typical case analysis of the vertical drilling system, the future development direction of the vertical drilling technology is predicted. The results show that, the existing vertical drilling technology can better meet the technical needs of rapid drilling in the middle-deep sections with high steep angles. While the stability of wireless information transmission and wear resistance of the push pad still need further improvement. The new type of vertical drilling system that is miniaturized (suitable for small boreholes) and resistant to high temperature and high pressure is in urgent need to fill the gaps in the market segment. Domestic independent vertical drilling systems have made great progress, some even surpass foreign products in key indicators such as temperature resistance, in addition to achieving the technical goal of anti-inclination successfully. Finally, based on the engineering geological conditions of Shunbei 11 well, feasible vertical drilling tools were recommended and achieved engineering goal finally. The research results can provide support for the drilling company to optimize the vertical drilling system based on engineering-geological conditions.

2014 ◽  
Vol 543-547 ◽  
pp. 387-390
Author(s):  
Hong Shan Zhao ◽  
Kun Zhang

Automated strap-down vertical drilling system (AVDS) with independent intellectual property rights is composed of a strap-down stabilization platform and a deviation control and correction mechanism. It performs deviation control and correction initiatively while drilling by applying dynamic push-lean, which can effectively solve the inclination control and fast drilling problems arising from high-steep structures and high dip formations. The system can release drilling pressure completely, so under the precondition of ensuring inclination precision, it could remarkably improve the penetration rate, shorten the drilling cycle and reduce the drilling costs. During the field test from 2436 to 2610.79m in well Anshun-1, inclination angle decreased to 0.25° from 6.25°. The average ROP was 1.02m/h, and the average footage was 87.4m. Compared with traditional drilling tools, it improved the penetration rate by 25.9% and the footage by 18.3%. The stability and reliability of the system was proved through the field test. It was suggested that field tests should be strengthened and AVDS applying for different borehole should be developed.


2011 ◽  
Vol 101-102 ◽  
pp. 1105-1108 ◽  
Author(s):  
Wei Zhang ◽  
Dong Sheng Zhang ◽  
Yong Shu Zhao

Under the condition of large inclined angle, the stability control of hydraulic support was always the challenge for the fully-mechanized mining in large inclined coal seams. Based on the specific geological conditions of 509 coalface with large inclined and high mining in Gaozhuang mine, the model of hydraulic support had been drawn by using SolidWorks software, and the inclination mechanical model of hydraulic support had been established to analyze its inclination stability along coalface. The calculation result shows that when the maximum inclination angle is 31° and the underhand angle is 10°, the minimum support resistance needed to keep the hydraulic support not dumping is 283.59 kN. Meanwhile, the critical support resistance required for the hydraulic support not to dump in inclination direction increases approximately linearly along with the increase of coalface mining height; under the same mining height condition, the critical support resistance increases along with the increase of the inclined angle. Therefore, the selection of the mining height and inclined angle of the coal seam must be considered at the beginning of the hydraulic support design.


2012 ◽  
Vol 57 (2) ◽  
pp. 363-373
Author(s):  
Jan Macuda

Abstract In Poland all lignite mines are dewatered with the use of large-diameter wells. Drilling of such wells is inefficient owing to the presence of loose Quaternary and Tertiary material and considerable dewatering of rock mass within the open pit area. Difficult geological conditions significantly elongate the time in which large-diameter dewatering wells are drilled, and various drilling complications and break-downs related to the caving may occur. Obtaining higher drilling rates in large-diameter wells can be achieved only when new cutter bits designs are worked out and rock drillability tests performed for optimum mechanical parameters of drilling technology. Those tests were performed for a bit ø 1.16 m in separated macroscopically homogeneous layers of similar drillability. Depending on the designed thickness of the drilled layer, there were determined measurement sections from 0.2 to 1.0 m long, and each of the sections was drilled at constant rotary speed and weight on bit values. Prior to drillability tests, accounting for the technical characteristic of the rig and strength of the string and the cutter bit, there were established limitations for mechanical parameters of drilling technology: P ∈ (Pmin; Pmax) n ∈ (nmin; nmax) where: Pmin; Pmax - lowest and highest values of weight on bit, nmin; nmax - lowest and highest values of rotary speed of bit, For finding the dependence of the rate of penetration on weight on bit and rotary speed of bit various regression models have been analyzed. The most satisfactory results were obtained for the exponential model illustrating the influence of weight on bit and rotary speed of bit on drilling rate. The regression coefficients and statistical parameters prove the good fit of the model to measurement data, presented in tables 4-6. The average drilling rate for a cutter bit with profiled wings has been described with the form: Vśr= Z ·Pa· nb where: Vśr- average drilling rate, Z - drillability coefficient, P - weight on bit, n - rotary speed of bit, a - coefficient of influence of weight on bit on drilling rate, b - coefficient of influence of rotary speed of bit on drilling rate. Industrial tests were performed for assessing the efficiency of drilling of large-diameter wells with a cutter bit having profiled wings ø 1.16 m according to elaborated model of average rate of drilling. The obtained values of average rate of drilling during industrial tests ranged from 8.33×10-4 to 1.94×10-3 m/s and were higher than the ones obtained so far, i.e. from 181.21 to 262.11%.


Author(s):  
S.X. Li ◽  
Z.H. Wang ◽  
D.M. Li ◽  
W.W. Duan ◽  
S. Mei ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuping Li ◽  
Xiaoju Liang ◽  
Xuguo Zhou ◽  
Yu An ◽  
Ming Li ◽  
...  

AbstractGlycyrrhiza, a genus of perennial medicinal herbs, has been traditionally used to treat human diseases, including respiratory disorders. Functional analysis of genes involved in the synthesis, accumulation, and degradation of bioactive compounds in these medicinal plants requires accurate measurement of their expression profiles. Reverse transcription quantitative real-time PCR (RT-qPCR) is a primary tool, which requires stably expressed reference genes to serve as the internal references to normalize the target gene expression. In this study, the stability of 14 candidate reference genes from the two congeneric species G. uralensis and G. inflata, including ACT, CAC, CYP, DNAJ, DREB, EF1, RAN, TIF1, TUB, UBC2, ABCC2, COPS3, CS, R3HDM2, were evaluated across different tissues and throughout various developmental stages. More importantly, we investigated the impact of interactions between tissue and developmental stage on the performance of candidate reference genes. Four algorithms, including geNorm, NormFinder, BestKeeper, and Delta Ct, were used to analyze the expression stability and RefFinder, a comprehensive software, provided the final recommendation. Based on previous research and our preliminary data, we hypothesized that internal references for spatio-temporal gene expression are different from the reference genes suited for individual factors. In G. uralensis, the top three most stable reference genes across different tissues were R3HDM2, CAC and TUB, while CAC, CYP and ABCC2 were most suited for different developmental stages. CAC is the only candidate recommended for both biotic factors, which is reflected in the stability ranking for the spatio (tissue)-temporal (developmental stage) interactions (CAC, R3HDM2 and DNAJ). Similarly, in G. inflata, COPS3, R3HDM2 and DREB were selected for tissues, while RAN, COPS3 and CS were recommended for developmental stages. For the tissue-developmental stage interactions, COPS3, DREB and ABCC2 were the most suited reference genes. In both species, only one of the top three candidates was shared between the individual factors and their interactions, specifically, CAC in G. uralensis and COPS3 in G. inflata, which supports our overarching hypothesis. In summary, spatio-temporal selection of reference genes not only lays the foundation for functional genomics research in Glycyrrhiza, but also facilitates these traditional medicinal herbs to reach/maximize their pharmaceutical potential.


Author(s):  
Dandan Li ◽  
Zhiqiang Zuo ◽  
Yijing Wang

Using an event-based switching law, we address the stability issue for continuous-time switched affine systems in the network environment. The state-dependent switching law in terms of the region function is firstly developed. We combine the region function with the event-triggering mechanism to construct the switching law. This can provide more candidates for the selection of the next activated subsystem at each switching instant. As a result, it is possible for us to activate the appropriate subsystem to avoid the sliding motion. The Zeno behavior for the switched affine system can be naturally ruled out by guaranteeing a positive minimum inter-event time between two consecutive executions of the event-triggering threshold. Finally, two numerical examples are given to demonstrate the effectiveness of the proposed method.


2019 ◽  
Vol 136 ◽  
pp. 04023
Author(s):  
Ming Zhao ◽  
Ke Li ◽  
Hong Yan Guo ◽  
KaiCheng Hua

Based on the special geological conditions of a tunnel in Qingyuan section of Huizhou-Zhanzhou Expressway, FLAC3d numerical simulation software is used to simulate the rheological properties and instability of surrounding rock in large-section fully weathered sandstone section, and the stability and loss of surrounding rock are analyzed. The deformation of the dome and the face at steady state is analyzed. It is found that: 1) when the surrounding rock is in a stable state, the deformation curve of the dome is smooth. When the surrounding rock of the face is unstable, the front of the face appears ahead. Deformation should be first strengthened on the surrounding rock in front of the face. 2) The arched foot is an important part of the instability of the surrounding rock. In order to prevent the expansion of the collapsed part, the arched part should be reinforced. 3) In order to obtain the limit state of surrounding rock stability, the strength of surrounding rock is reduced, and the strength reduction coefficient corresponding to the displacement sudden point is taken as the safety factor of rock stability around the hole, and the stability safety coefficients of surrounding rock of each construction step are greater than 1.2. 4) The dynamic standard values of deformation control in the whole construction stage are obtained by analyzing the deformation curves of each data monitoring point with time in the corresponding time period of each construction step.


2012 ◽  
Vol 461 ◽  
pp. 652-655
Author(s):  
Ying Wu ◽  
Peng Zhang ◽  
Xiao Li

Directional drilling technology is an important and very promising trenchless pipeline crossing technology. On the basis of the related literature research at home and abroad and our pipeline construction site investigation, focuses on several common soil properties are introduced, and then the formation adaptability of directional drilling is analyzed. The drilling selection methods are made when drilling in the specific geological conditions, and the possible risks of the construction process have been classified in the directional drilling.


2012 ◽  
Vol 516 ◽  
pp. 516-521
Author(s):  
Chung Chieh Cheng ◽  
Dong Yea Sheu

This study describes a novel process to drill small holes in brittle materials such as glass, silicon and ceramic using a self-elastic polycrystalline diamond (PCD) drilling tool. In order to improve the surface roughness and reduce crack of the small holes, a new type of self-elastic PCD drilling tool equipped with vibration absorbing materials inside the housing was developed to fabricate small holes in glass in this study. The self-elastic PCD drilling tools could absorb the mechanical force by the vibration absorbing materials while the PCD tool penetrates into the small holes. Compared to conventional PCD drilling tools, the experimental results show that high-quality small holes drilled in glass can be achieved with cracking as small as 0.02mm on the outlet surface using the self-elastic PCD drilling tool.


2021 ◽  
Author(s):  
Tianying Wang ◽  
Yanjun Zhou ◽  
Honglin Tang ◽  
Shihua Zhang ◽  
Haiqing Tian

Abstract The JCSM concept (short for Jackup Combined Semisubmersible Multifunction Platform) is a new type of semisubmersible platform presented by the first author, which overcomes the shortcomings of the available semisubmersible platforms, and combines the advantages of the traditional semisubmersible platform, the Jackup platform and the new FPSO concept - IQFP. Due to the complicated interaction between stability and hydrodynamic performance, it is necessary to explore the effect of geometrical parameters of the main body on the stability and hydrodynamic performance in order to obtain the optimal design plan of a JCSM platform. Firstly, the structure components and innovations of the JCSM were briefly reviewed in order to facilitate readers to understand its full picture. Then, six independent geometric parameters were selected by carefully studying the shape characteristics of the initial design plan of a JCSM study case. Furthermore, the stability heights and motion responses of various floating bodies of the JCSM case with different geometric parameters in wave were calculated using boundary element method based on potential flow theory. Lastly, effect of the shape parameters on stability and hydrodynamic performance of the JCSM was qualitatively evaluated. The research would shed lights on the shape design of the JCSM main body.


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