超越负载工况下轮式起重机起升系统特性研究

发布时间：2018-06-26 05:47

本文选题：轮式起重机 + 起升系统　；参考：《吉林大学》2011年硕士论文

【摘要】：起重机械是工程建设中不可或缺的工程机械之一,在我国经济建设中发挥着举足轻重的作用。特别是随着我国经济社会的快速前进,高铁、石油化工、建筑等行业飞速发展,起重机械满足市场需求量越来越大,起重机械所起的作用亦愈加明显。轮式起重机是起重机械众多种类中具有特别突出位置,轮式起重机以其自由移动式底盘、多工况等优点,在工程建设中得到了广泛的应用。轮式起重机的出现极大地提高了人类的劳动生产率,减轻了劳动强度,加速了经济建设。轮式起重机自从推出市场至今已经经历了一个快速、健康的发展时期,但是随着科学技术的快速发展,用户对轮式起重机的操作性能的要求也越来越高。起升系统是轮式起重机中最为关键的子系统之一,起升系统性能的好坏直接影响整个起重机的操作性能,故提高起升系统的性能对提升起重机可靠性有着非常重要的意义。目前,轮式起重机起升系统存在下降抖动、二次起升下滑等缺陷,这些缺陷使起重机不能发挥正常的起升性能,极端情况下,还有可能会曹成严重的安全事故,故对轮式起重机下降性能的研究具有非常重要意义和技术地位。本文将以工程起重机中应用广泛的轮式起重机作为原型车,对其起升液压系统性能进行测试、分析。针对起升系统存在的问题,主要对起升系统下降抖动问题展开研究,通过对起升系统下降性能测试曲线的对比分析,设计了新型平衡阀阻尼网络端盖。新型平衡阀阻尼网络端盖主要是通过应用阻尼网络的滤波特性,使进入平衡阀先导控制油腔的压力油压力趋于平稳,同时由于阻尼的“隔压”作用使平衡阀和制动器的启闭时间得到了良好的匹配,从而最大限度上消除了起升系统的下降抖动问题,提升了起升系统的性能。本文主要做了以下工作: (1)介绍了目前国内外轮式起重机起升机构典型的几种液压控制系统,主要分析了阀控开式液压系统、泵控开式液压系统和泵控闭式液压系统的优缺点以及控制原理,为起升系统的优化设计提供了理论参考。 (2)对现有起重机进行起升系统各工况的测试,通过分析测试数据,发掘影响起升系统性能的相关因素。实车测试结果显示,样机起升系统在进行下降操作时,存在抖动现象,分析测试曲线可知,平衡阀先导控制油腔压力存在波动,并且平衡阀与制动器的开启时间不符合设计要求,从而导致系统出现压力波动,致使重物下降出现抖动现象。 (3)通过分析起重机出现下降抖动现象的机理,利用阻尼网络匹配技术,优化了平衡阀先到控制油路,设计了新型平衡阀阻尼网络端盖。新型平衡阀先导阻尼网络在进行参数匹配时,不仅考虑了良好的滤波性能,而且对阻尼网络与制动器启闭时间进行了匹配,推导了阻尼网络参数选取的计算关系式,为新型阻尼网络端盖参数的合理选取提供了计算依据。 (4)通过AMESim软件对典型起重机起升系统系统进行了物理建模,根据实际工况对模型进行仿真,主要分析了起重机起升系统的下降性能。仿真结果表明现有起重机起升系统平衡阀与制动器的启闭时间不合理,在某些工况下会出现下降抖动现象,为了提升起升系统的可靠性,需要采取合理的措施来消除该缺陷。 (5)针对现有系统存在的缺陷,运用AMESim软件对改进后的起升系统进行了物理建模和仿真,对比分析了改进后起升系统的下降性能。运用不同阻尼网络参数的平衡阀端盖进行模型仿真,结果表明新型阻尼网络端盖的使用修正了平衡阀与制动器的启闭时间关系,有效滤除了进入平衡阀先导油腔的压力波动,很大程度上提升了起升系统下降性能。 (6)根据理论计算和仿真分析结果,对新型阻尼网络端盖进行了实车测试,经过对不同阻尼参数的测试,结果表明新型阻尼网络端盖在对平衡阀先导控制压力进行滤波和改善平衡阀与制动器的启闭时间关系上具有显著的效果。只要新型阻尼网络各参数选取合适,可以有效解决起重机下降抖动问题。本文利用阻尼网络技术,对起升系统进行了参数匹配,优化了起升系统关键控制元件的参数关系,从理论上提供了提升起升系统下降性能的科学依据;并且通过AMESim软件对起重机起升系统进行了物理建模和仿真,从仿真的角度验证了理论分析的正确性,并且通过实车测试,验证了仿真结果的有效性。仿真与实车测试数据均表明,本论文设计新型平衡阀阻尼端盖具有良好的稳压作用,能够有效解决起升系统下降抖动的问题,极大地提升了起重机起升系统的可靠性。
[Abstract]:The lifting machinery is one of the indispensable engineering machinery in the construction of the project. It plays an important role in the economic construction of our country. In particular, with the rapid progress of our country's economy and society, the rapid development of the industries, such as high speed rail, petrochemical, construction, etc., the lifting machinery satisfies the demand for the market more and more, and the function of the lifting machinery is also more and more important. It is obvious that the wheel crane is a special prominent position in many kinds of lifting machinery. The wheel crane has the advantages of free moving chassis and multiple working conditions. It has been widely used in engineering construction. The appearance of wheel crane greatly improves the labor productivity, reduces the labor intensity and accelerates the economic construction.
The wheel crane has experienced a rapid and healthy development since it launched the market. But with the rapid development of science and technology, the requirement of the operating performance of the wheel crane is becoming higher and higher. The lifting system is one of the most important subsystem of the wheel crane, and the performance of the lifting system is directly affected by the performance of the hoisting system. With the operating performance of a crane, it is very important to improve the hoisting system's performance to improve the reliability of the crane. At present, the hoisting system of the wheel crane has a drop jitter, two rise and fall and other defects. These defects make the crane not able to perform the normal lifting performance. In extreme cases, there may be serious Cao. Safety accidents, therefore, the study of the drop performance of wheel cranes has very important significance and technical status.
In this paper, a wheeled crane used widely in the engineering crane is used as a prototype vehicle, and the performance of its lifting hydraulic system is tested and analyzed. In view of the problems existing in the lifting system, this paper mainly studies the problem of the drop jitter of the lifting system, and designs a new balance valve by comparing and analyzing the performance test curve of the lifting system's descent performance. The end cover of the damping network is mainly through the application of the filter characteristics of the damping network, which makes the pressure oil pressure of the balance valve control the oil chamber smooth. At the same time, the opening and closing time of the balance valve and the brake can be well matched because of the "pressure isolation" effect of the damping, thus the maximum elimination is made. The drop jitter problem of hoisting system improves the performance of hoisting system.
The main work of this article is as follows:
(1) several typical hydraulic control systems of hoisting mechanism of wheel crane at home and abroad are introduced. The advantages and disadvantages of valve controlled open hydraulic system, pump controlled open hydraulic system and pump controlled closed hydraulic system are mainly analyzed, and the theoretical reference is provided for the optimization design of lifting system.
(2) test the working conditions of the hoisting system of the existing crane, and through the analysis of the test data to explore the related factors affecting the performance of the lifting system. The actual vehicle test results show that there is a jitter phenomenon in the lifting system when the lifting system is carried out. The analysis test curve shows that the balance valve pilot control oil chamber pressure fluctuates, and the balance is balanced. The opening time of the valve and the brake does not meet the design requirements, resulting in pressure fluctuations in the system, resulting in heavy weight dropping and jitter.
(3) through the analysis of the mechanism of the drop jitter of the crane, the damper network matching technology is used to optimize the balance valve first to control the oil path, and the new balance valve damping network end cover is designed. The new balance valve pilot damping network not only considers the good filtering performance, but also the damping network and the brake when the parameter matching is matched. The relationship between opening and closing time is matched, and the calculation formula of damping network parameters is deduced, which provides a basis for the rational selection of the end cover parameters of the new damping network.
(4) the typical crane hoisting system system is modeled by the AMESim software, and the model is simulated according to the actual working condition. The performance of the lifting system is mainly analyzed. The simulation results show that the opening and closing time of the balance valve and brake of the existing crane lifting system is not reasonable, and there will be a drop of shaking in some working conditions. In order to improve the reliability of hoisting system, reasonable measures should be taken to eliminate this defect.
(5) in view of the defects existing in the existing system, the physical modeling and Simulation of the improved hoisting system are carried out with AMESim software, and the decrease performance of the improved hoisting system is compared and analyzed. The model simulation is made with the balance valve cover of different damping network parameters. The results show that the use of the new damping network end cover is modified by the balance valve and the balance valve. The opening and closing time relationship of the brake effectively removes the pressure fluctuation entering the pilot oil chamber of the balancing valve, and greatly improves the descent performance of the lifting system.
(6) according to the theoretical calculation and the results of simulation and analysis, the new damping network end cover is tested. After testing the different damping parameters, the results show that the new damping network end cover has significant effect on the relationship between the balance valve pre control pressure filtering and the improvement of the opening and closing time of the balance valve and the brake. Suitable parameters of damping network can effectively solve the problem of crane's descent and jitter.
This paper uses the damping network technology to match the hoisting system, optimizes the parameter relation of the key control elements of the hoisting system, provides a scientific basis for the lifting system to improve the performance of the lifting system, and carries out the physical modeling and Simulation of the lifting system of the crane through the AMESim software, and verifies the theory from the angle of simulation. The correctness of the analysis is discussed and the validity of the simulation results is verified by the real vehicle test. The simulation and the actual test data show that the design of the new balance valve has a good stabilizing effect in the design of the balance valve, and can effectively solve the problem of the drop jitter of the lifting system and greatly improve the reliability of the crane lifting system.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH213.6

【引证文献】