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In this article, considering the factors such as well trajectory and tubing string structures, the transient shut‐in tubing string pressure fluctuation model of ultra‐deep high‐temperature and high‐pressure (hereinafter referred to as HTHP) gas well is established, the propagation of pressure wave along the well depth is obtained, and the effects of different production and shut‐in time on the fluctuating pressure and its variation range are analyzed. Through calculation and analysis, it can be seen that there are differences in pressure waveforms at different well depths. The closer to the bottom of the well, the more delayed the occurrence of water hammer, and the smaller the water hammer pressure value. The larger the production, the greater the pressure wave velocity, and the closer to the wellhead, the more obvious the change. For well X, the pressure wave velocity in the well section below 6500 m varies greatly with the increase of production. When the production is 140 × 104 m3 D−1, the difference of pressure wave velocity between the bottom hole and the wellhead is 105.19 m s−1. After instantaneous shut‐in, the wellhead pressure increases by 3.2% compared with the initial pressure and the bottom hole pressure increases by 0.6%. [ABSTRACT FROM AUTHOR]

In order to solve the problem where the traditional intelligent inspection robot only has a single inspection function, we studied the use of a dry powder (including an ultra-fine dry powder) as a fire-extinguishing medium for the first time. In fire-extinguishing robots, the spray pressure is difficult to control, and there are several other issues. For integrated inspection, an intelligent, nitrogen-driven fire-extinguishing robot using a dry powder in a pressure-controlled spray was developed. On this basis, in order to investigate nitrogen-driven dry powder particle spraying as a gas–solid two-phase mechanism, as well as the flow characteristics and the influence of relevant parameters on the spraying effect, a nitrogen-driven dry powder particle spraying system was established as part of a gas–solid two-phase computational fluid dynamics model. The flow field of the spraying system and the particle motion characteristics were analyzed to explore the micro-mechanisms of the influence of different driving pressures, pipe diameters, and nozzle configurations on the spraying of the dry powder. In order to investigate the macroscopic effect of dry powder spraying where the gas–solid two-phase micro-mechanisms could not be revealed, an experimental platform was set up, and the experiments verified the accuracy of the numerical simulation results. We also investigated the dry powder spraying effect under different driving pressures, pipe diameters, nozzle configurations, and loading ratios. Finally, an orthogonal test was designed based on the results of the single-factor experiments to find the best combination of parameters required to achieve the optimal spraying effect. The research results can provide a theoretical and technical reference for the design and development of nitrogen-driven dry powder spraying systems. [ABSTRACT FROM AUTHOR]

Objectives: This article investigates the corrosion behavior and mechanical-property changes of S135, G105, and V150 drill pipe materials in a high-temperature-resistant, potassium amino poly-sulfonate drilling fluid, which has good lubrication performance and contains CO2/H2S, by applying an 80% yield-limit-load simulation. The results show that the CO2-corrosion behavior of G105, S135, and V150 drill pipes are obvious under the simulated constant-load-stress-corrosion environments at the wellhead, well-middle, and bottomhole positions. Compared to uncorroded drill pipes, S135 and V150 drill pipes have increased strength and yield ratios, decreased fracture elongation, and increased sensitivity to hydrogen embrittlement under H2S action, and V150 has a greater risk of stress-hydrogen embrittlement. The strength and yield ratios of G105-material drill pipes decrease, while the fracture elongation increases; the intensity-change amplitude levels are ranked V150 > G105 > S135, and the fracture-elongation-change amplitude is ranked G105 > S135 > V150. The tensile-performance-change amplitude and the SSCC (Sulfide-Stress-Corrosion Cracking) sensitivity of G105 and V150 drill pipes were the highest at the bottomhole. S135 drill pipe materials were most affected by pitting and tensile action at the wellhead, and they had the with the largest SSCC sensitivity. [ABSTRACT FROM AUTHOR]

Due to the particularity of raw materials and the complexity of processes, the petroleum and petrochemical industry involves a variety of disaster risks in production, transportation, storage and etc. However, there are three barriers in the emergency rescue of the petroleum and petrochemical industry, scene separation, data isolation and inefficient coordination. No matter the application of existing technology or the proposed method and concept, the situation cannot be broken quickly. By analyzing these problems existing in 5G communication technology, artificial intelligence and petroleum and petrochemical emergency rescue, this paper puts forward the concept of petroleum and petrochemical remote collaborative emergency technology, analyzes the development trend of remote collaborative emergency technology, and prospects the petroleum and petrochemical emergency rescue technology.

Leakage is one of the most serious challenges for the safe production of high‐pressure gas wells for its high risks, including abnormal annular pressure, natural gas accumulation, and environment pollution, but available methods can hardly accurately measure the leakage type and depth, which are the key parameters for the rigless leakage repair and risk assessment. Therefore, this paper proposes a method to measure the leakage based on the characteristics, which combines qualitative and quantitative measurement together. Qualitative measurement considers the annular pressure, tubing pressure, liquid level, cement quality, and workover history. Quantitative measurement is determined by noise logging, electromagnetic logging, pressure logging, and temperature logging. The logging should be optimized according to the qualitative measurement. The method was successfully applied in high‐pressure gas well belonging to Tarim Oilfield. Two potential leakage types are provided based on the annular pressure, liquid level, cement quality, and workover history, including tubing leakage and linger hanger leakage. Based on the potential leakage types, the pressure difference, logging devices string, stopping length, and time are optimized to make the engineering logging reliable. Through measurement, two leakage points are found in tubing string. One is tubing body crack at the depth of 2724 m and the other is tubing thread leakage at the depth of 5211.7 m, which well matches the production data. [ABSTRACT FROM AUTHOR]