查詢結果分析
來源資料
頁籤選單縮合
題名 | 聚丙烯對焊接之加熱與冷卻過程=Heating and Cooling Processes of Polypropylene During Butt Welding |
---|---|
作者 | 溫超東; Wen, Chudong; |
期刊 | 中華技術學院學報 |
出版日期 | 20010900 |
卷期 | 23 2001.09[民90.09] |
頁次 | 頁105-112 |
分類號 | 472.14 |
語文 | chi |
關鍵詞 | 聚丙烯; 塑膠焊接; 對焊接; 焓公式; Polypropylene; Plastic welding; Butt welding; Enthalpy equation; |
中文摘要 | 本計畫在於研究熱塑性塑膠聚丙烯在實施熱元件對焊接時在加熱和冷却過程中之暫態溫度變化,由焊件之溫度分佈圖和溫度-時間圖我們可以判斷出適當的焊接加熱和冷却所需的時間。 研究時採用隱含有限差分法,關於焊接時相變化之問題,本研究採用焓公式。為了獲得較準確的分析結果,材料的比熱係以DSC分析結果後以公式來模擬,此比熱包含了焊接時固/液相間相變化的潛熱。 數值分析結果顯示了1.在自然對流之冷卻情形下,板件對焊接時板件上方和下方之溫度不對稱情形並不嚴重,以致於一般之焊接應用均忽略此溫度不對稱之影響2.較厚的焊件因焊件表面和焊件中心之溫度差較大,故焊接之溫度應較低而焊接時間需要較久3.所需的冷郤時間因焊件厚度不同而可較焊接機或材料供應商所提供的冷卻時間減少50%~70%。 |
英文摘要 | The heating and cooling processes of polypropylene during heating element butting welding were investigated. From the temperature distribution and temperature history, the heating time and cool time required for welding are suggested. The implicit finite-difference method was used in the research. Enthalpy equation was used to solve the phase change problem during welding. In order to obtain more accurate analytical results, the specific heat modeled by equations according to the DSC results was used. The latent heat for solid/liquid phase change was included in the specific heat. The numerical analysis shows that: 1. The non-symmetrical temperature distributions between the upper plate and the lower plate are not significant. Therefore the influence due to the non-symmetrical temperature distri-butions on the butt welding is usually neglected. 2. The thicker the plate, the lower the welding temperature and the longer the welding time are required. This is because that during welding the thicker plate presents larger temperature difference between the center and the surface. 3. Welding time can be reduced from 50% to 70% in according to the thickness of the weldment. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。