本文關(guān)鍵詞： 復(fù)合材料護(hù)環(huán) 車削加工 熱膨脹 過盈裝配　出處：《哈爾濱工業(yè)大學(xué)》2014年碩士論文　論文類型：學(xué)位論文

【摘要】：近年來，隨之我國國民經(jīng)濟(jì)的快速發(fā)展，我國對(duì)電力的需求也隨之不斷增加，為此對(duì)大容量、大功率發(fā)電機(jī)組的需求就顯得尤為迫切。電機(jī)中的轉(zhuǎn)子護(hù)環(huán)是發(fā)電機(jī)的重要部件。在發(fā)電機(jī)正常運(yùn)轉(zhuǎn)時(shí)，護(hù)環(huán)受到來自轉(zhuǎn)子的交變壓力及兩者旋轉(zhuǎn)時(shí)巨大的離心力，為此對(duì)護(hù)環(huán)的力學(xué)性能和護(hù)環(huán)與轉(zhuǎn)子的裝配要求尤其苛刻。現(xiàn)役的奧氏體反磁鋼電機(jī)護(hù)環(huán)自重大、依賴進(jìn)口，制約著我國大容量發(fā)電機(jī)的自主發(fā)展。于此同時(shí)，纖維樹脂基復(fù)合材料在工程上的應(yīng)用卻越來越成熟、越來越廣泛，其比強(qiáng)度比模量高、磁導(dǎo)率低、加工成型方便、成本低。纖維樹脂基復(fù)合材料護(hù)環(huán)作為工程結(jié)構(gòu)件應(yīng)用，需要對(duì)材料進(jìn)行一定的機(jī)械加工，才能滿足裝配及精度的要求。護(hù)環(huán)與轉(zhuǎn)子之間為過盈配合，兩者之間的合理裝配對(duì)于轉(zhuǎn)子的正常運(yùn)轉(zhuǎn)具有重要的意義。 針對(duì)以上問題，本文設(shè)計(jì)并制造了600MW級(jí)汽輪發(fā)電機(jī)用碳纖維復(fù)合材料護(hù)環(huán)。首先，選擇復(fù)合材料體系—樹脂基體、增強(qiáng)纖維、固化劑、促進(jìn)劑，確定制備工藝、進(jìn)行鋪層設(shè)計(jì)。其次對(duì)復(fù)合材料進(jìn)行了車削加工及已加工表面的粗糙度測試，從而優(yōu)化了切削參數(shù)。再者，對(duì)復(fù)合材料的熱膨脹系數(shù)及熱膨脹變形量進(jìn)行了實(shí)驗(yàn)和模擬分析，最終進(jìn)行了復(fù)合材料護(hù)環(huán)縮比件與轉(zhuǎn)子進(jìn)行裝配的仿真模擬，外護(hù)環(huán)與轉(zhuǎn)子的裝配實(shí)驗(yàn)完成了鋪墊工作。 本文使用有限元軟件對(duì)復(fù)合材料的以下兩個(gè)方面進(jìn)行了模擬仿真： 1）轉(zhuǎn)子與護(hù)環(huán)之間的過盈裝配采用熱裝法與冷裝法結(jié)合的方法，為了保證兩者之間裝配實(shí)驗(yàn)的順利進(jìn)行，分別模擬了護(hù)環(huán)在高溫下內(nèi)表面的徑向膨脹量、轉(zhuǎn)子在低溫下的徑向收縮量。模擬結(jié)果表明：對(duì)于600MWe級(jí)汽輪發(fā)電機(jī)用碳纖維復(fù)合材料護(hù)環(huán)的縮比件（縮小比例為4:1），其在120℃時(shí)的徑向膨脹量為0.0447mm，轉(zhuǎn)子在-110℃時(shí)的徑向收縮量為0.681mm。同時(shí)還模擬了玻璃纖維及其與碳纖維混雜復(fù)合材料在高溫下的熱膨脹量，結(jié)果表明，玻璃纖維復(fù)合材料護(hù)環(huán)的徑向熱膨脹量在溫度升高至120℃達(dá)到0.389mm，比碳纖維復(fù)合材料護(hù)環(huán)提高了9倍。 2）護(hù)環(huán)與轉(zhuǎn)子之間的過盈配合量對(duì)于兩者工作時(shí)的應(yīng)力有很大影響，為此本課題模擬了轉(zhuǎn)子與護(hù)環(huán)縮比件在不同過盈裝配量時(shí)的應(yīng)力分布情況，以及護(hù)環(huán)受到過盈裝配產(chǎn)生的離心力的作用下，接觸面上的應(yīng)力分布情況。結(jié)果表明，護(hù)環(huán)及轉(zhuǎn)子在0.2mm過盈量裝配時(shí)，護(hù)環(huán)內(nèi)邊界的應(yīng)力達(dá)到20.42MPa，小于碳纖維復(fù)合材料護(hù)環(huán)的縱向壓縮強(qiáng)度900MPa。護(hù)環(huán)在50Hz頻率下旋轉(zhuǎn)過程中，環(huán)向最大膨脹位移量約為0.05mm，在60Hz極限頻率下的環(huán)向最大膨脹位移量約為0.075mm，該膨脹量處于護(hù)環(huán)與轉(zhuǎn)子間的過盈配合量的設(shè)計(jì)范圍內(nèi)，，因此不會(huì)影響轉(zhuǎn)子與護(hù)環(huán)間的整體配合。
[Abstract]:In recent years, with the rapid development of China's national economy, the demand for electricity in our country is also increasing, so the large capacity. The demand of high-power generator set is particularly urgent. The rotor ring is an important part of generator. When the generator is running normally. The ring is subjected to the alternating pressure from the rotor and the great centrifugal force when they rotate. Therefore, the mechanical properties of the retaining ring and the assembly requirements of the ring and rotor are particularly harsh. Dependence on imports restricts the independent development of large capacity generators in China. At the same time, fiber resin matrix composites are more and more mature and widely used in engineering, their specific strength ratio modulus is high, permeability is low. Fiber resin matrix composite ring is used as an engineering structure, which needs to be machined. Only in order to meet the requirements of assembly and accuracy, the interference fit between the retaining ring and the rotor is necessary, and the reasonable assembly between the two is of great significance to the normal operation of the rotor. Aiming at the above problems, the carbon fiber composite ring for 600MW turbogenerator is designed and manufactured. Firstly, the composite system-resin matrix, reinforcing fiber, curing agent and accelerator are selected. The preparation process was determined and the layering design was carried out. Secondly, the cutting parameters were optimized by turning the composites and measuring the roughness of the machined surfaces. The thermal expansion coefficient and thermal expansion deformation of composite material were tested and simulated. Finally, the assembly of composite retaining ring and rotor was simulated. The assembly experiment of the outer protection ring and the rotor has completed the paving work. In this paper, the following two aspects of composite materials are simulated by finite element software: 1) the interference assembly between rotor and retaining ring adopts the method of hot loading and cold assembling. In order to ensure the smooth assembly experiment between the two, the radial expansion of the inner surface of the retaining ring at high temperature is simulated respectively. The radial shrinkage of the rotor at low temperature. The simulation results show that for the carbon fiber composite retaining ring of 600MWe class turbogenerator, the shrinkage ratio is 4: 1. The radial expansion is 0.0447 mm at 120 鈩

本文編號(hào)：1479759