Papers by Keyword: Overturning Moment

Abstract: The transverse shock tester is an important device to assess the shock resistance ability of ship equipments. Because of the shock point and the gravity center of the tester are not on the same horizontal, the device may generate huge overturning moment. We adopt the finite element method to do the dynamics analysis of the transverse shock tester, using the parallelogram mechanism as its guide device, to analysis its output waveform and other problems, and find: it will appear saw-tooth acceleration waveform result from the oscillation caused by the overturning moment during the impact process; the oscillation will greatly increases the hinge load--changed following the oscillation amplitude periodically--of the parallelogram mechanism; the hinge inner friction almost has no effect on the impact tester movement or the output waveform. From the above statements, we can see that the parallelogram mechanism can not only share the overturning moment generated by the transverse impact, but also can ensure to get the desired output waveform, thus it suits to be used as the guide device of the transverse shock tester.

Abstract: In article work of a fragment of a wall design from blocks from autoclaved aerated concrete (AAC) is considered at its floor-by-floor leaning on monolithic overlapping of the building with a monolithic ferroconcrete framework and conditions of ensuring stability (not losses) a considered fragment within one floor at action on it the overturning moment from wind loading.

Abstract: Studies on leakage and friction have received considerable attention in scroll compressor, especially which between the fitting surface of orbiting scroll and fixed scroll, as they affect the scroll compressor performance. According to the scroll compressor working principle and structure, combined with the force model of the orbiting scroll, the overturning moment on the orbiting scroll was analyzed and verified by a specific example, in which the azimuth angle and of the overturning moment action line were calculated and compared. The results show that the overturning moment will have a significant effect not only on the leak and friction loss at the fitting surface of orbiting and fixed scroll, also on the dynamic characteristics of the orbiting scroll due to the linear change of the azimuth angle and the unstable of the azimuth angle . The result is helpful for the study on leakage, friction, and the dynamics and tribology coupling problem research of scroll compressor.

Abstract: Because of cross roller-slewing bearing structure have a certain degree of particularity, and two sets of cross rollers is equivalent to two columns roller stack situation, therefore it should deduce roller calculation formula for two sets of roller respectively. According to the stress of the slewing bearings, we proceed load distribution calculation synthetically under the center of bearing axial force, overturning moment and radial force. Finally, based on the above formula for calculating the bearing load distribution and through the Matlab software, we analyze the influence of some parameters on the bearing load distribution. For ensuring bearing design parameter, it has the certain reference value.

Abstract: The iron ladle is a kind of large metallurgy equipments and used for collecting and carrying iron water. According to the factual demand of produce, some corporation wanted to enlarge the capacity of the idle from 65t to 75t only by increasing the height of ladle. This paper is aimed at the changing idle which the capacity is 75t and built up its 3D numerical model. According to the constant of the iron water capacity, it used the method of modeling to find the angle of the ladle taphole and made sure the ladle couldn't overturn automatically by studying the process of overturning. Then this paper worked out the overturning moment so that it could provide mechanics data for the analysis of the finite element and the reformation of the corporation.

Abstract: Reinforced concrete grid frame core-tube structure system is a new system. This article draws the conclusion that grid frame core-tube has high stiffness and obvious space affection, and that its basic mechanics properties is better than frame core-tube structure and similar to tube structure through the comparison of two tube structure systems, which the Inner tube is similar to grid frame core-tube and the outer tubes respectively are frame and high beam - column frame tube. It puts forward some reasonable suggestions for the future designation of this structural system.

Abstract: By simulation experiments, the relation between the starting friction torque of a blade bearing and the overturning moment is explored in order to disclose the nonlinear evolution characteristics of the sample mean and variation coefficient of the starting friction torque. Via the variation analysis of the test data, the result indicates that with the rise of the overturning moment, the sample mean is nonlinearly increased and the sample variation coefficient is nonlinearly decreased in view of the overall situation, at which there is a sensitive spot where the sample variation coefficient makes larger abnormally. This is a new discovery. Perhaps it can lay the foundation for analyzing the starting friction torque measurement system and for designing the blade bearing system.

Abstract: Railway wind-break wall is widely used, which is of significant importance to prevent running vehicles from suffering the risk of overturning. In the paper, application of railway wind-break wall and specific details of its structure are introduced. Wind tunnel test and CFD simulation are widely used in the researches on the performance of railway wind-break wall and some important results are summarized. Based on the review, developments of railway wind-break wall in the future are provided.

Abstract: This study is conducted to provide a compensation formula to design the stowing devices - a tie-down rod and a stowage pin - and an alarm system to prevent an overturning of a container crane under wind loads. Two method, namely FSI(fluid-structure interaction) analysis and wind tunnel test, are adopted in this investigation. In order to evaluate the effect of wind load on the stability of the crane, 50-ton class container crane widely used in container terminals is adopted for analytic model and 19-values are considered for wind direction as design parameter. First, the wind tunnel test for the reduced scale container crane model is performed according to the wind direction using an Eiffel type atmospheric boundary-layer wind tunnel. Next, FSI analysis for a full-scale container crane is conducted using ANSYS and CFX. Then, the uplift force obtained from FSI analysis is compared with that yielded by the wind tunnel test. Finally, a formula is suggested to compensate the difference between the FSI analysis and the wind tunnel test.

Abstract: An overload limiter is used to prevent its overturning accident during an operating of a movable crane. Recently the indirectly measuring method, which measures hoisting load and overturning moment of overload limiter, demands instead of the existing method, which measures only hoisting load. The indirectly measuring method is how to conduct the hoisting load and overturning moment as measuring the load of hydraulic cylinder for a luffing driving of boom. So we need to develop the many-angular pin type load cell with the measuring angle of ±10 degree instead of the existing load cell with the measuring angle of ±2 degree. In this study we conducted the finite element analysis in order to evaluate the effect of the aspect ratio of measuring cross section on the measuring limit of the load cell to develop the many-angular pin type load cell. For this investigation, the aspect ratio of measuring cross section and load applying angle were adopted as design parameters and the stresses of measuring part were evaluated for each parameter.