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Steering drilling technology can achieve precise control of wellbore trajectory, and related technologies have been widely used in the field of petroleum drilling. This paper proposed a new steering drilling technology based on the Pulsed Arc Plasma Shockwave Technology (PAPST),Plasma Pulse Steering Technology (PPST). PAPST transforms electric energy into mechanical energy by discharging electrodes, which can break rock. On the basis of PAPST, PPST can precisely control the discharge time and break the rock in the specified direction at the bottom of the well, so as to realize guided drilling. First, the discharge mechanism and guiding mechanism of the PPST were studied separately. Then, the discharge control model of PPST was established to explain the feasibility of using this technology to achieve drilling guidance. Finally, to verify the actual effect of this technology on rock breaking, an experiment was carried out with self-developed experimental equipment. Through the study of the mechanism and discharge control model of PPST, it is considered that it is feasible to use this technology to achieve guidance in theory. The experimental results show that the sandstone samples were damaged and a large area of pits appeared after the shockwave, and the ultrasonic penetration test results showed that there was damage inside the rock. As the number of impacts increased, the rock damage became more severe and fracture occurred. Therefore, it is feasible to apply PPST to the directional fracture of bottom hole rock. In summary, this technology has very good application prospects. For the first time, this paper proposed the idea of applying PAPST to steering drilling. Through the research on the steering mechanism and the experiment, the feasibility of this technology was proved and the theoretical basis was provided for the application of this technology in the field of oil drilling.

The exact calculation and control for cementing annulus flow pressure is very important, especially for formations with narrow density windows. It is easy to form belly shaped arc concave boreholes because of the uneven hole enlargement rate in the process of practical drilling. Research on the change law of annulus flow pressure loss in an arc concave borehole is helpful for controlling the annulus pressure profile accurately. The structure of flow pressure loss is analyzed through the establishment of a flow pressure loss equation in an arc concave borehole; the fluid flow control equation is established, the solving method is studied, the analysis software is developed, the flow pressure loss is calculated, the influence law of hole enlargement rate and fluid displacement on the flow pressure loss are analyzed, and the results are verified by numerical simulation software, Fluent. The results show that the flow pressure loss in arc concave borehole sections is less than that in normal boreholes within the scope of common hole enlargement rates. The offset between software calculation results and numerical simulation results are in the scope of engineering allowable error. The conclusions provide a powerful technical reference for analyzing cementing annulus pressure characteristics accurately.

Three-dimensional visualization of seismic profile data can better display seismic data information than traditional profile display, but there are mosaic errors in grid mosaic. In order to solve the problem of false mosaics, an adaptive mosaic method is proposed, first in the pixel shader Calculate the sample point most relevant to the current sample point on the next track, and then map its relative offset in the time direction to the tilt mode and render it to the texture. When filling the vertex index, fully consider the tilt of the adjacent sample points on the same track In order to realize the adaptive tessellation of vertices; finally, the effectiveness of the proposed method is verified through experiments.

A new digital image method for measuring soil landslide displacement is presented in this paper. First, the principle of surface fitting method to determine the sub-pixel gray value is introduced. Second, the optical experimental system and the specimen used in this experiment are described in detail. Then, the soil micro-displacement field can be measured by obtaining the clear image sequence of soil micro-slide of an expansive soil sample under water load and searching the gray value in sub-pixels by digital image surface fitting technology. The results show that through the optical system, this nondestructive testing method can improve the measurement accuracy, and has a very good prospect of application in the study of soil landslide. After getting a great deal of useful data, the principal of the displacement in different times and in different locations under different water load can be obtained by drawing displacement curves, consequently the experimentation can provide useful data for disaster prevention and mitigation research and actual construction. In addition, if using a CCD with higher resolution and more effective record area, or using synthetic aperture technology to increase effective record area, the accuracy of the experiment are expected to be further enhanced.