Papers by Keyword: Mechanics Analysis

Abstract: Deepwater pipeline repairing machine (DPRM) is an appropriative equipment which is used to repair damaged deepwater oil and gas pipelines. With the development of deepwater oil and gas exploitation, inventions of such kinds of equipments are urgent priorities. Grinding technology is used in DPRM to remove pipeline anticorrosive coating. It is easy to cut the pipeline excessively when grinding pipeline anticorrosive coating for large orality of deepwater pipelines, which is not conducive to use mechanical connector to seal the pipeline. In order to settle this problem, the rotating compliant mechanism is designed and the grinding tool is steel wire brush. Based on the theory of boundary layer, the underwater rotating mechanical model of grinding tools is established to gain the relationship between grinding drag torque and grinding tool radius, rotational speed, and positive pressure. The grinding experiment gives the effect of structural parameters of steel wire brush on removing anticorrosive coating and indicates that medium density bowl type steel wire brush is the best choice. Finally, the grinding pipeline anticorrosive coating test is completed to verify the rationality of the design of grinding device. These studies provide technical basis for the development of deepwater multifunctional pipeline repair machinery.

Abstract: Based on the Rankine earth mechanics theory, the mechanics model that the helical blade working in earth is simplified in this paper, and an experimental platform for discovery the relationship that between helical blade structure parameters and the driving torque is designed when the helical blade working in the earth. Through a series of experiments, comparative analysis the effect of the helical blade width, pitch on the driving torque, the experimental results verified the feasibility of the helical blade operation way of working in the earth, which laid the theoretical foundation for the subsequent development of the spiral in the earth device.

Abstract: Takeoff is extremely important to long jump. The paper analyzes the mechanics characteristics of takeoff for long jump by means of the theory of neural network. It firstly discusses some importantly influencing factors for long jump in theory. On the basis of description of the theory of Artificial Neural Network, the back propagation network is applied to model the long jump. The results show that an excellent performance of long jump is depend on a rapid run-up speed and the rhythm of the final two steps.

Abstract: The paper analyzes some basic technologies for billiards sport. The basis of the research is considering the billiards as a rigid body. Hence, the theory of rigid mechanics can be applied to discuss billiards sport. On the basis of analysis of basic form and mechanics principle for billiards sport, goal mechanical condition of elastic collision and the skill of jumping bar for billiard balls are technically analyzed. The analysis results displays that the billiard sport can be calculated from two aspects of translation and rotation. In addition, a greater angular velocity can accelerate the speed and shorten the horizontal distance in jumping bar.

Abstract: Through the site investigation of defects on a secondary highway tunnel portal in Guizhou Province and survey data, this paper aims to analyze the detection mechanism of all defects. Controlled by bias effect of tunnel portals, the defects of portal lining cracking and leakage are pretty serious. A fully understanding of these mechanisms can help to improve and fine design and construction of tunnel portal, reducing the production of defect.

Abstract: In order to minimize the friction when the linear motion unit in the movement, the new type unit based on permanent magnet was designed. The Halbach Array magnet structure was adopted in the unit. It can realize the stable suspension with the combination of gravitation and repulsion. The new type units have good performance and broad application prospects.

Abstract: This article aims at the fracture problem of the transmission linkage of swaying yarn machine, based on the improved transmission mechanism, used the theory of Kinematics and Mechanics, the paper analyzed and calculated the transverse force and the longitudinal force on the transmission linkage of the swaying yarn machine, and got the force direction and size, and the maximal position and value of bending moment in the one rotary process of the driving crank of transmission linkage, to supply the theory basis of solving the problem of transmission fracture of swaying yarn machine.

Abstract: Design of closed loop drilling tool in the rotary steering drilling system is a bit in recent installation guide controlled stabilizer, and placed on the upper drill collar two downhole assembly form of stabilizer. The set of parameters for the MATLAB software programming is used to solve the three moment equation and the downhole assembly mechanical properties. With continuous beam column theory, the mechanics features of the BHA are analyzed. It is analyzed focused on the relationship between the guiding force and the bit deflecting force, the relationship between the hole deviation angle and bit deflecting force, the relationship between the drill press and bit deflecting force, the relationship between the guiding force position on the well inclined plane and bit deflecting force through the tables and figures based on closed-loop rotary steerable drilling system.

Abstract: In this paper, it is put forward a new kind of gyroscope and Theoretical analysis and simulation for it. it is based on the latest proposed a kind of MEMS gyroscope, the micro machine rotor of the liquid floated gyroscope in the thermal field has carried on the stress analysis and simulation. The magnetic field is a kind of drive, Gyroscope lumen is composed of stator and detecting electrode plates,it is filled with 2 # industrial white oil in the inner cavity body,2 # industrial white oil support this gyroscope of rotor . The measuring accuracy of the rotor is very high, and the rotor's drift stability is also greatly improved. But the rotor is governed by thermal field, it is still mentioned the main reason for the precision. For the generation of thermal field mainly comes from two parts: heat field and eddy heat. Comsol software is presented in this paper, the thermal field of the rotor were analyzed, and the current in the magnetic field to join 280 mA, 580 mA, 780 mA and 1800 mA, the temperature distribution for the magnetic field, the rotor's blow plate of temperature is less than the up plate of temperature; The rotor side wall is the highest temperature and its the lining is greater than the outer wall temperature; Around the rotor 2 # industrial white oil to join as the speed of 2500 rmp, 3500 rmp, 5500 rmp, 8000 rmp, because of the large flow rate, the eddy current is big, so the temperature increased. Two physical field coupling together to produce energy losses, affect the material performance, at the same time bring local vibration,this phenomenon results in the decrease of accuracy of measurement. Therefore, we need to change the rotor structure and materials to reduce the influence on measurement accuracy. At the same time for the next step, the stress analysis of rotor under the confined space for experiment platform test provide simulation data and the theoretical analysis.The sidewalls of the rotor machining into the radian of 0.05 mm.

Abstract: According to the characteristics of the marine pipelines, we present a kind of ships in-pipe reconnaissance robot for different types of pipes. Finish an optimized design for the adjusting mechanism by mechanics analysis of the metamorphic mechanism, and by the analysis of overcoming obstacles performance, the robot can not only adapt to different types of pipes, but also has good obstacle surmounting abilities. No doubt it improves the stability and reliability of the robot. The force and movement trajectory of the robot is obtained by using ADAMS, which carries on the kinematics analysis. Simulation results show that the robot can pass through 330 ~ 486 mm (diameter) pipes smoothly and can pass 5 mm circular obstacle by spring within the scope of the traction.