【摘要】：渦旋壓縮機(jī)是一種發(fā)展迅速的高效容積式流體機(jī)械,目前對其核心部件渦旋盤的特性研究越來越深入。其中,高速切削加工過程中熱變形的產(chǎn)生是影響渦旋盤加工精度和質(zhì)量的主要原因。文章主要是以組合型線渦旋盤的高速精密銑削加工過程中的切削熱問題為研究對象,主要工作內(nèi)容如下:1.組合型線的渦旋盤數(shù)控銑削加工。選用數(shù)值逼近的方法加工渦旋盤,先采用粗加工的加工策略,然后在粗加工的基礎(chǔ)上采用精加工方式獲取幾何尺寸、形狀精度及表面質(zhì)量符合要求的工件。2.任意時刻和位置處的溫度變化情況分析。采用單一變量的方法,模擬了y值一定時,x=z=20mm處不同的熱源熱量引起溫度隨時間的變化規(guī)律,呈現(xiàn)先增高后降低的趨勢,20s時溫度達(dá)到最大值,此時溫差最大為208℃,隨著時間的增加,溫差逐漸減小,直至為零;t=20s時刻,不同z值的情況下,溫度隨著x值的變化規(guī)律,基本上在x=0.06m位置處,溫度基本趨于室溫。3.三個變形區(qū)熱源熱量的理論分析和數(shù)值計算。渦旋盤與刀具之間的摩擦切削熱主要是來自于剪切區(qū)和刀-件摩擦區(qū),研究了這兩個變形區(qū)產(chǎn)生的熱量對渦旋盤的影響。剪切區(qū)熱量比例分配系數(shù)R1和刀-件摩擦區(qū)產(chǎn)生的熱量比例分配系數(shù)R3都隨著主軸轉(zhuǎn)速的提高而增加,主軸轉(zhuǎn)速越高,傳入工件的熱量越少。4.剪切溫度和應(yīng)變-應(yīng)力的變化規(guī)律及實際銑削加工過程中溫度-時間變化情況。隨著切削速度v的增加,剪切應(yīng)變率?(5)每升高213/s,剪切應(yīng)力s?大約增加20MPa,剪切溫度一直呈現(xiàn)上升趨勢,當(dāng)主軸轉(zhuǎn)速達(dá)到7000r/min時,此時渦旋盤溫升緩慢,切削溫度基本保持在754℃左右。在實際銑削加工渦旋盤時,低速加工階段溫度值穩(wěn)定后基本保持103℃左右,高速精加工階段初始時刻溫度值已達(dá)到570℃以上,隨著時間的變化,溫度值逐漸趨于750℃左右。通過對渦旋盤的高速精密銑削加工過程,切削熱問題的研究并與實際銑削加工過程中的溫度進(jìn)行比較,具有很好地一致性,這對于減少渦旋盤溫升,減少熱變形,提高其加工質(zhì)量和精度具有指導(dǎo)意義,也為變截面渦旋型線的高速精密加工切削熱問題提供了參考價值。
[Abstract]:Scroll compressor is a kind of high efficiency displacement fluid machine with rapid development. At present, the characteristics of vortex disk, its core component, are studied more and more deeply. The thermal deformation in high speed cutting is the main reason that affects the machining precision and quality of scroll disk. In this paper, the problem of cutting heat in the high speed and precision milling process of the combined line vortex disk is studied. The main work is as follows: 1. Numerical Control Milling of Scroll disk of combined profile. The method of numerical approximation is used to process the scroll disk. Firstly, rough machining strategy is adopted, and then the geometric dimension, shape precision and surface quality of workpiece. 2 are obtained by finishing on the basis of rough machining. Analysis of temperature variation at any time and position. By using the method of single variable, the variation of temperature with time caused by different heat sources at a certain y value of 20mm is simulated. The temperature increases first and then decreases to the maximum at 20 s, and the maximum temperature difference is 208 鈩，

本文編號：2163566