【摘要】：作為重物搬運(yùn)重要設(shè)備的起重機(jī)在現(xiàn)代化生產(chǎn)過(guò)程中應(yīng)用越來(lái)越廣。由于電力、石油、化工,運(yùn)輸?shù)刃袠I(yè)的快速發(fā)展,起重機(jī)的種類越來(lái)越多、市場(chǎng)需求量也越來(lái)越大。 目前工程起重機(jī)廣泛采用液壓驅(qū)動(dòng),回轉(zhuǎn)機(jī)構(gòu)是起重機(jī)的重要機(jī)構(gòu),由于回轉(zhuǎn)機(jī)構(gòu)作業(yè)時(shí)具有轉(zhuǎn)動(dòng)慣量大的特性,所以作業(yè)時(shí)壓力沖擊較大,這種壓力沖擊會(huì)影響相關(guān)液壓元件工作壽命,容易損壞相關(guān)的壓力傳感器和引起整機(jī)振動(dòng),造成動(dòng)作微動(dòng)性差,使得工作效率降低,從而制約回轉(zhuǎn)系統(tǒng)的工作性能。合理的液壓油路可以提高作業(yè)效率、改進(jìn)整機(jī)性能、改善工作條件、減小發(fā)熱量等�；剞D(zhuǎn)機(jī)構(gòu)作業(yè)時(shí)應(yīng)盡量平穩(wěn),制動(dòng)時(shí)間應(yīng)盡量短,起動(dòng)、制動(dòng)、換向時(shí)壓力沖擊要小,為滿足這些要求,我們有必要對(duì)回轉(zhuǎn)機(jī)構(gòu)液壓油路進(jìn)行專門分析研究。只有了解系統(tǒng)的動(dòng)態(tài)特性,才能對(duì)系統(tǒng)的各種參數(shù)進(jìn)行合理的匹配。以往我國(guó)起重機(jī)制造企業(yè)在起重機(jī)液壓系統(tǒng)的設(shè)計(jì)和評(píng)估分析上一般都是根據(jù)人們的經(jīng)驗(yàn)和必要的產(chǎn)品借鑒,以靜態(tài)考慮為主來(lái)設(shè)定設(shè)計(jì)方案,再通過(guò)實(shí)驗(yàn)在樣機(jī)上發(fā)現(xiàn)問(wèn)題。單純地運(yùn)用實(shí)驗(yàn)法,不僅僅要花費(fèi)很大的精力和物力,而且有時(shí)變更參數(shù)或條件都比較困難,甚至可能無(wú)法實(shí)現(xiàn)。如果采用傳統(tǒng)的傳遞函數(shù)理論分析法,不但很麻煩而且稍有失誤其結(jié)果可能與實(shí)際相差甚遠(yuǎn)。而利用仿真分析的方法,可以使這一復(fù)雜的問(wèn)題簡(jiǎn)單化。 本文是來(lái)源于學(xué)校和企業(yè)合作的“移動(dòng)式起重機(jī)產(chǎn)品液壓控制回路測(cè)試評(píng)估系統(tǒng)開(kāi)發(fā)”實(shí)際項(xiàng)目,對(duì)汽車起重機(jī)回轉(zhuǎn)液壓系統(tǒng)展開(kāi)研究,以目前同類系統(tǒng)普遍存在的問(wèn)題為切入點(diǎn),分析如何實(shí)現(xiàn)回轉(zhuǎn)機(jī)構(gòu)作業(yè)時(shí)壓力平穩(wěn)、縮短制動(dòng)時(shí)間、減小起動(dòng)、制動(dòng)和換向時(shí)的壓力沖擊、改善系統(tǒng)的調(diào)速特性。 1.對(duì)50t汽車起重機(jī)的回轉(zhuǎn)機(jī)構(gòu)理論分析,建立回路的液壓控制系統(tǒng)數(shù)學(xué)模型,應(yīng)用傳遞函數(shù)法理論上分析了對(duì)液壓控制系統(tǒng)有影響的一些參數(shù)。 2.建立回轉(zhuǎn)機(jī)構(gòu)液壓系統(tǒng)仿真模型,在50t汽車起重機(jī)樣車上進(jìn)行實(shí)驗(yàn),測(cè)出回轉(zhuǎn)機(jī)構(gòu)液壓系統(tǒng)兩種工況時(shí)壓力動(dòng)態(tài)曲線,通過(guò)仿真結(jié)果和實(shí)驗(yàn)結(jié)果對(duì)比,修正參數(shù)使模型更真實(shí)地反應(yīng)實(shí)際情況,驗(yàn)證了仿真模型的正確性。 3.基于回轉(zhuǎn)機(jī)構(gòu)的AMESim仿真模型進(jìn)行仿真分析,分別分析了轉(zhuǎn)動(dòng)慣量、負(fù)載阻力矩、緩沖閥的彈簧、緩沖閥的開(kāi)口面積、泵的流量、換向閥的彈簧剛度、換向閥的開(kāi)口面積、緩沖溢流閥的彈簧預(yù)緊力對(duì)系統(tǒng)的動(dòng)態(tài)特性的影響。分析了如何減緩回轉(zhuǎn)機(jī)構(gòu)啟動(dòng)和制動(dòng)時(shí)壓力沖擊、縮短制動(dòng)時(shí)間、改善系統(tǒng)的調(diào)速特性,提高整機(jī)性能、作業(yè)效率和安全性。 根據(jù)起重機(jī)回轉(zhuǎn)機(jī)構(gòu)液壓系統(tǒng)分析提出的建議對(duì)提高整機(jī)性能非常重要,希望本文的研究成果能對(duì)以后的同類產(chǎn)品的設(shè)計(jì)、評(píng)估提供一定的參考價(jià)值。
[Abstract]:Cranes, as important equipment for handling heavy objects, are used more and more widely in the modern production process. Due to the rapid development of electric power, petroleum, chemical and transportation industries, there are more and more kinds of cranes and more market demand. At present, hydraulic drive is widely used in engineering cranes. The rotary mechanism is an important mechanism of crane. Because the rotary mechanism has the characteristic of large moment of inertia when working, the pressure shock is bigger when working. This pressure shock will affect the working life of the relevant hydraulic components, damage the related pressure sensors and cause the vibration of the whole machine, and cause the poor action micro-motion, which will reduce the working efficiency, and thus restrict the working performance of the rotary system. Reasonable hydraulic oil circuit can improve the working efficiency, improve the performance of the whole machine, improve the working conditions, reduce the heat generation and so on. In order to meet these requirements, it is necessary to make a special analysis and study on the hydraulic oil circuit of the rotary mechanism in order to meet these requirements, the working time of the rotary mechanism should be as stable as possible, the braking time should be as short as possible, and the pressure shock should be small when starting, braking and reversing. Only by understanding the dynamic characteristics of the system, can the parameters of the system be properly matched. In the past, the design and evaluation analysis of crane hydraulic system in crane manufacturing enterprises in our country are generally based on the experience of people and the reference of necessary products, and the design scheme is set mainly by static consideration, and then the problems are found in the prototype through experiments. The simple application of the experimental method not only costs a lot of energy and material resources, but also sometimes it is difficult to change the parameters or conditions, and it may even be impossible to realize. If the traditional transfer function theory analysis method is adopted, it is not only troublesome but also slightly wrong, and the result may be very different from the actual one. The method of simulation analysis can simplify this complex problem. This paper is from the school and the enterprise cooperation "mobile crane product hydraulic control loop test and evaluation system development" actual project, the automobile crane rotary hydraulic system is carried out the research, Based on the common problems existing in the same system at present, this paper analyzes how to realize the stable pressure, shorten the braking time, reduce the pressure shock when starting, braking and reversing, and improve the speed regulation characteristics of the system. 1. Based on the theoretical analysis of the slewing mechanism of 50t truck crane, the mathematical model of the hydraulic control system of the loop is established, and some parameters which have influence on the hydraulic control system are analyzed theoretically by the transfer function method. 2. The simulation model of hydraulic system of rotary mechanism is established, and the pressure dynamic curve of hydraulic system of slewing mechanism is measured on a 50t truck crane sample car. The simulation results are compared with the experimental results. The modified parameters make the model reflect the actual situation more realistically, and verify the correctness of the simulation model. 3. Based on the AMESim simulation model of the rotary mechanism, the moment of inertia, the load resistance moment, the spring of the buffer valve, the opening area of the buffer valve, the flow rate of the pump, the spring stiffness of the reversing valve and the opening area of the reversing valve are analyzed. The effect of spring pre-tightening force of buffer relief valve on the dynamic characteristics of the system. This paper analyzes how to slow down the pressure shock during start-up and braking of rotary mechanism, shorten the braking time, improve the speed regulation characteristics of the system, and improve the performance, working efficiency and safety of the whole machine. According to the analysis of hydraulic system of crane slewing mechanism, it is very important to improve the performance of the whole machine. It is hoped that the research results of this paper can provide some reference value for the design and evaluation of similar products in the future.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2011
【分類號(hào)】：TH213.6

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 夏樹(shù)立;百米登高平臺(tái)消防車回轉(zhuǎn)液壓系統(tǒng)仿真研究[D];大連理工大學(xué);2012年

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本文編號(hào)：2433091