Papers by Keyword: Heavy Load

Abstract: Heavy payload forging manipulators are mainly characterized by large load output and large capacitive load input. The relationships between outputs and inputs have greatly influence about the control and the reliability. Forging manipulators have become more prevalent in the industry today. They are used to manipulate objects to be forged. The most common forging manipulators are moving on a railway to have a greater precision and stability. They have been called the railbound forging manipulators. In this paper one presents the general aspects of a railbound forging manipulator, like geometry, structure, general kinematics and forces of the main mechanism from such manipulator. Kinematic scheme shows a typical forging manipulator, with the basic motions in operation process: walking, motion of the tong and buffering. The lifting mechanism consists of several parts including linkages, hydraulic drives and motion pairs. An idea of establishing the incidence relationship between output characteristics and actuator inputs is proposed.

Abstract: With the rising of public environmental awareness and energy saving goal, high efficient transmission of ballscrew is widely used for production equipment. Of all the ballscrew application, heavy loading is the most stringent operation condition. The crucial techniques for this application are ball recirculation system and lubrication design. In this article, a heavy-load type ballscrew is verified to meet the application requirements through experiments, dynamic simulations and test runs on test bench.

Abstract: In order to study elastohydrodynamic lubrication characteristics of cylindrical roller under heavy load and unsteady state, a testing machine is designed for measuring line contact film thickness and shape according to optical interference principle. The experimental apparatus is mainly made of glass block reciprocating motion systems, ball or roller rolling rotation system, loading system, speed control systems, lighting systems and image acquisition system. Moving parts is formed by the slider-crank mechanism. Specimen is accompanied by a pair of floating trial roller bearing. Specimen load is applied by leverage. The entrainment velocity of roller is approximate sinusoidal variation during a cycle. Experiment interference image is satisfactory, can provide reliable experimental data for future research.

Abstract: The growth rates of stress in the hexagon , square and octagon cement blocks under different vehicle loads were analyzed using the finite element method (FEM). The growth rate of bottom layer stress of the hexagon is the smallest among them when vehicle loads increase. Under the 400kN loads, the growth rate of bottom layer stress of the hexagon significantly reduced as the thickness increase. When its thickness is up to 28cm,the bottom layer stress is the smallest among the three kinds of shapes. The results show that the hexagon cement block is the most suitable for overload vehicles obviously when compared to the square and octagon cement block. Therefore, hexagon cement block is the most suitable for the roads which are always under heavy and overload vehicles .

Abstract: Along with the rapid development of highway, regenerated materials are used more frequently in highway engineering. Featured by low carbon and environmental protection, it confirms to the philosophy of sustainable development in China. However, the fast developing transport industry brings more heavy vehicles and heavy-load traffics take place commonly, thus causing diseases to China’s highway in advance. The major highway disease is wheel ruts. The appearance of wheel rut not only affects the service life of highway and the comfort level of driving, but also threatens driving safety, thereby causing huge losses and harmful effect. According to an investigation, 70% of highway suffers from the problem of wheel rut. High temperature and heavy load are two most important factors of wheel rut. This paper will take Tieling-Fuxin line for example to analyze the pavement performance and test the material performance of regenerated mixtures under different loads.

Abstract: By studying the advantages and disadvantages of the conventional automatic linear door systems, it was found that flat permanent magnet linear synchronous motors (PMSLM) can satisfy high-speed long-stroke heavy-load door systems better than other techniques. In order to reach a long lifespan, the authors compared five possible topologies with flat PMLSM, and then designed a kind of magnetically suspended door system driven by a single-sided flat PMLSM and suspended by the normal force of the motor. The results demonstrate that the prototype door system satisfies the requirements.

Abstract: The problem of variable cross-section beam carrying a moving heavy load is investigated. UG software is used to build a three-dimensional model of the beam. The finite difference method and finite element method are used static analysis for the variable cross-section beam carrying a moving heavy load. The static deformation of the beam guide surface is obtained. Comparing the data of the two method, the feasibility of the method is verified. This paper give a guide surface load curve research method of variable cross-section beam carrying a moving heavy load.

Abstract: IEEE802.15.4 defines MAC and PHY specification for low-rate wireless personal area networks (LR-WPANS), which targets wireless networking among low-rate, low-power and low-cost devices for short range telecommunication. As the wireless sensor network used in ward monitoring system need to handle large amounts of data, this paper proposes an improved backoff algorithm in slotted CSMA/CA by introducing a weighting algorithm of. According to the comparison of and , we can dynamic change the minimum contention window each time at CSMA/CA begins. By NS2 simulation, when the traffic load is large, the delay time, packet loss rate and jitter of the improved dynamic algorithm can be significantly reduced.

Abstract: This paper introduces working principle of screw oscillating hydraulic cylinder. Structure parameters and process parameters influence on mechanical efficiency is analyzed, simultaneously, structure parameters and process parameters influence on volumetric efficiency is also analyzed. the maximum mechanical efficiency and optimal spiral angle are acquired. Total transmission efficiency model is established. Transmission efficiency experimental test is carried out, experiment test efficiency is basically in accordance with calculated efficiency.

Abstract: In order to study the dynamic response law of semi-rigid base of asphalt pavement under heavy load traffic, the viscoelastic system model under heavy load was established based on measured loading pattern and axle load distribution with the finite element software ANSYS12.0. Heavy load traffic effect on the dynamic response of semi-rigid base of asphalt pavement was discussed . The results show that semi-rigid asphalt pavement structure dynamic response value changed with the increase of axle load; time varying regularity of stress and strain was not the same in different directions.