Core drilling has been widely used in mineral exploration with diamond-impregnated drilling technology. Automation is a critical technology in improving core drilling efficiency and reducing core drilling costs, but there is no complete automation that can control the entire core drilling process. In this paper, an electric drive laboratory drilling system was established using programmable logic controller (PLC) technology. A proportional integration differentiation (PID) control algorithm was developed to achieve closed-loop control of the weight-on-bit (WOB) during the drilling process. Four drilling modes were developed for the drilling system, and their performances were verified by drilling test. A constant-speed mode is proposed as the most suitable mode for the system. The recommended rate of penetration (ROP) of the rock sample and bit used in the experiment was obtained through the power optimization drilling test. The results show that the optimal rotation speed ranged from 700 to 1000 rpm, and the optimal ROP ranged from 2.0 to 2.6 m/h.

Fiber-optic gyroscopes (FOGs)-based Measurement While Drilling system (MWD) is a newly developed instrument to survey the borehole trajectory continuously and in real time. However, because of the strong vibration while drilling, the measurement accuracy of FOG-based MWD deteriorates. It is urgent to improve the measurement accuracy while drilling. Therefore, this paper proposes an innovative scheme for the vibration error of the FOG-based MWD. Firstly, the nonlinear error models for the FOGs and ACCs are established. Secondly, a 36-order Extended Kalman Filter (EKF) combined with a calibration method based on 24-position is designed to identify the coefficients in the error model. Moreover, in order to obtain a higher accurate error model, an iterative calibration method has been suggested to suppress calibration residuals. Finally, vibration experiments simulating the drilling vibration in the laboratory is implemented. Compared to the original data, compensated the linear error items, the error of 3D borehole trajectory can only be reduced by a ratio from 10% to 34%. While compensating for the nonlinear error items of the FOG-based MWD, the error of 3D borehole trajectory can be reduced by a ratio from 44.13% to 97.22%. In conclusion, compensation of the nonlinear error of FOG-based MWD could improve the trajectory survey accuracy under vibration.

The study focused on the relation of structure, property, and application of composite prepared by organic cation intercalated montmorillonite (Mt). Herein a new kind of green and steady ionic liquid, 1‐hexadecyl‐3‐methylimidazolium chloride monohydrate (C₁₂mimCl), was chosen as the intercalated agent. This study used molecular dynamics (MD) modeling to examine the interlayer microstructures of montmorillonite intercalated with C₁₂mimCl. The C₁₂mimCl intercalation was relatively fast with a large rate constant. The process was affected by the initial concentration of the solution; the basal spacing increased to 2.08 nm after intercalation. The coordination of electrostatic interaction and hydrogen bonding expelled water molecules out of the clay gallery and bound the layer together, which led to the dehydration of clay. The intercalation of C₁₂minCl into Mt interlayer space affected rheology of the system and improved various properties. This organic clay composite was environmentally friendly and could be used in drilling fluid system. These models provided insights into the prediction of synthesized organic cationic‐clay microstructure and guidelines for relevant engineering applications.

Sonic drilling is a novel sampling technology applied in many fields. Based on SolidWorks software, a dynamics virtual prototyping is utilized to develop a physical sonic driller by demonstrating collision detection and optimizing overall layout and key component structures. Key hydraulic and structural parameters are optimized using a mathematical model. Search for the optimized parameters and operating conditions for this multi-body mechanical system is conducted experimentally. The practical results show that the virtual prototype technology not only shortens the design cycle but also improves the quality of the conventional design. The new sonic driller designed by this method is both environmentally friendly and smarter.

In the production process of oil and gas wells, the migration of solid particles, such as mud and sand, often leads to screen pipe clogging, resulting in production reduction or even shutdown. Controlled plasma pulse plugging removal technology is a new physical method for unplugging. Plasma, generated by the electrical explosion of the wire, then triggers a shock wave, which can remove the plugging. In this paper, the performance of controllable plasma pulse plugging removal technology is evaluated by simulating the plugging state of the downhole screen through laboratory experiments. The test results of screen plate unplugging effect evaluation fully show that the plasma pulse decongestion technology can carry out effective decongestion, can effectively reduce the pressure behind the clogging zone and increase the flow rate of the clogging zone, and is suitable for different screen plate blockage states such as mild, moderate and severe. Thus, this technology has a good application prospect.