| This paper is associative with the project "Research on the equipment and instrument of No-Dig Guided Boring paving pipes", which comes from JiLin province's scientific and technical Committee.Our country is just on the development period on which the economic construction is advancing rapidly. And all kinds of spreading pipes' construction quantities are very large, which are used in petroleum, coal gas, electric power, telecommunication, water supply, sewage, and etc. The traditional trench technology possesses infinite localization character breakage character, such as effecting traffic and environment, construction period lasting a long time, cost being high, and etc. So trench technology is no long suit of the new era's demand. Furthermore, the construction is very difficult or can't going along at all in the situations such as historic protect sections, busy streets, crop and plant protect sections, freeways, railroads, buildings, rivers, and etc, so trenchless technology emerges as the times require. It is such a construction technology which carrying through every underground pipes exploration, paving, replacing and repairing within the least earth digging quantity. And it has many virtues such as not destroying road surface, nor affecting traffic and business management, nor polluting environment, and having high synthesis economy benefit. Although trenchless technology in our country has biggish development these years, there are also quite differences compared with other countries. Observing the instances all over our country, the spreading pipes' construction quantities using trenchless technology is no more than one percent. And the majority paved pipes used the method of trench technology. According to relate datum, the spreading pipes' construction quantities using trenchless technology occupy ten percent of whole works, and the quantities are raise year after year. Some cities' proportions are even greater than this. Why trenchless technology is not applied entireness in our country? On the one hand, the original base is very weakness, and the devotion in advance for purchasing construction equipment is very high, and the correlation department doesn't think much of the technology. On the other hand, the causes concerned with technique and equipment are very important.Guided Boring is one of primary construction methods in the industry of trenchless technology. Compared with other construction methods of paving pipes, Guided Boring method has little affection on the environment with fast speed, and can control the direction of paving pipes, and have high construction precision. The most notable characteristic is the high precision of paving pipes. Especially at area with complicated pipes' net in cities, this method can control paving position exactly, avoiding damaging other underground establishment. The paved pipes under the barrier are very deep, having protected function for pipes, and with few maintenance costs. The costs are lowest in many situations.Directional Drill is the chief construction equipment of Guided Boring. It is used to provide feeding force, dragging force, rotating torque, controlling angle of incidence and aiding breaking rod. The capability of Directional Drill effects drilling efficiency, operators' working intension, construction quality, utilizing energy sources, construction costs, and etc. directly. So it has important significance to carrying through deep research on Directional Drill and guiding design and construction using the conclusion.The design of Directional Drill in existence is adopted analogy methods, namely consulting of similar kind of drill. So the design is short of enough theoretic hereunder, and this situation restrict the more development of Directional Drill. This paper develops Model JFK-15 Trenchless Directional Drill on the base of theoretic analysis according to the demand of design parameters. The research work and conclusion are as follows:1. Research on the feeding mechanism. In this part, we choose double-force feeding mechanism by use of hydraulic motor and chain as our project on the base of contrasting different projects, and the mechanism was designed and calculated. It is shown by practicing that this mechanism works calmly and credibly, and feeding/ drawing force meet the design's demands. And it can lighten the bear of the motor and the chain efficiently, as well as reduce system's working pressure, cut down the wholly dimensions of the drill.2. Research on the rotating mechanism. On the base of contrasting different projects, we choose two hydraulic motors and reducer driving mode as our mechanism. The two motors are laid on two cater-corner of the output axial of the power head. This structure can reduce motor's displacement, reduce system working pressure, improve the steady quality of power head, reduce impact force, and lengthen the longevity of pillows and gears. So it meets the demands very well.3. Designing the clamping mechanism and doing theory analyses and calculation. This mechanism operates conveniently, works steady and reliably. And it can ease the operator labor intensity, improve construction efficiency.4. The theory of finite element is used to conducting analysis of intensity and rigidity on basic shaft of power head and sideway so that to test their capability. From the results, the conclusion can be drawn about how to improve structure to make them more logical. 5. The hydraulic system is designed. Three oil circuits system is used in the drill, and energy is assigned in reason, so the system meets logical relation of different motions. There are safety relief valves in both main engine and power station, and reliability of hydraulic system is much better.6. The theory of optimum design is introduced into the design of hydraulic system. Object function of hydraulic line is built which considered both energy loss and pipeline's volume, and the program is designed, then optimum design is conducted. The rational pipeline size is determined.As entirely hydraulic drill, dynamical property's stand or fall of hydraulic system has important effect on the reliability, stability, using life and etc. to the equipment. While currently existing researches on Directional Drill are most about the static state property. So it has important meaning to study dynamical property on hydraulic system of Directional Drill. This paper analyses and studies the dynamical property on feeding hydraulic system and dragging hydraulic system of the manufactured Directional Drill. The math model about dynamical property of hydraulic system is built and emulation analysis is carried by using emulation software. The research content and conclusion are as follows:1. The math models about motors' section of feeding hydraulic system and dragging hydraulic system are built. Two kinds of work condition are emphases: step change of flow and step change of load. The effect about correlation parameter to motor's hydraulic natural frequency (ω_n) and hydraulic damping factor (ξ) is analyzed, and the methods of elevating system's respond speed and enhancing stability are summed.2. The emulation models about feeding system and rotating system are built by using of software AMESim, and emulation analyses are proceed. The conclusion can be drawn from the emulation result that the system is steady and dynamic response is very fast at the condition of turnaround suddenly and load increasing suddenly in the existing parameters. 3. According to the emulation analyses on the series connection work condition of rotating system, the conclusion is drew that there is comparatively large difference about the load-bearing states of the two motors.4. The emulation analyses are preceded by changing some parameters of system. The correlative factors which influence stability and transition time are summed up from the emulation curve. And then the methods about how to improve dynamic response characteristic of feeding system and rotating system are extracted.5. Against parallel work condition of rotating system, the output shaft's turn angle is used as subject investigated and emulation analyses are preceded. The correlation parameters' influence to the precision of turn angle is obtained from the emulation result. And then the methods about how to improve the precision of turn angle are extracted. The precision of turn angle affects the conduction precision of drilling orbiting directly.Experiments are put after the drill having been manufactured. It can be shown from the experimental results that the emulation analysis conclusions about dynamical property are correct, and it can also be seen that the drill's capability meets design demand. The drill can be operated conveniently, working reliable and possessing construction capability.
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