【摘要】：近年來,聚乙烯管道被廣泛應用于市政工程當中,其中,有相當一部分接頭采用了熱縮帶連接或熱熔擠出焊連接。這兩種連接方式操作簡單,連接速度快,連接效果良好,且成本較低,但兩種連接方式分別使用時存在諸多缺陷,連接可靠性相對不足。本項目針對兩種方法的復合應用進行研究,以期獲得綜合連接的優(yōu)異效果。目前,在市政工程中很少有將兩種方法聯(lián)合使用的情況,因此熱縮帶和熱熔擠出焊兩種連接復合應用沒有施工作業(yè)指南及驗收標準,更沒有系統(tǒng)和完整的技術規(guī)程,從文獻資料中,也幾乎沒有將兩種方法聯(lián)合使用的研究成果,為此有必要進一步深入研究兩種連接方式的復合操作工藝、復合連接效果、耐久性以及復合性能的檢測及評判方法。本文依托中國水利水電七局的塑鋼纏繞排水管接頭連接研究項目,針對以上問題,從原材料試驗分析、復合連接工藝設計、組合連接試件性能測試和全尺寸接頭試驗等方面對接頭作了系統(tǒng)研究。主要內(nèi)容和成果如下:(1)對PE接頭材料作了基本的性能測試,在此基礎上,確定了熱縮帶連接方法中加熱噴槍火焰高度、噴槍行走速度與熱縮帶粘貼溫度的關系,以及熱縮帶粘貼溫度與粘結強度的關系。通過加熱噴槍火焰高度、噴槍行走速度、熱縮帶粘貼溫度與粘結強度的綜合分析,提出熱縮帶連接加熱工藝參數(shù):熱縮帶連接方法加熱火焰高度以15cm左右為宜,加熱火焰行走速度以1 0cm/s～12.5cm/s為宜,控制溫度在110℃～120℃較好。此外,管材表面油污,灰塵等雜質會顯著降低熱縮帶的粘接效果;(2)通過組合連接和單獨熱熔連接兩種類型的試件試驗證明,組合連接試件的拉伸強度高于單獨連接試件的強度。組合連接接頭在熱熔擠出焊焊接斷裂之后并不立即破壞,熱縮帶通過塑性變形仍然能夠給試件提供4MPa左右的強度,并且破壞前還會產(chǎn)生較大幅度的變形。無論是熱熔擠出焊單獨連接還是復合連接,焊縫寬度在4～6mm時達到最高強度;(3)熱熔焊和熱縮帶復合連接的接頭抗拉性能和斷裂伸長率滿足要求,通過單獨熱熔擠出焊連接試件和熱熔擠出焊復合熱縮套連接的試件的不透水性試驗發(fā)現(xiàn),兩種接頭在0.4Mpa的水壓下均無滲水情況。熱熔擠出焊受鹽溶液和堿溶液影響較小,但對酸溶液敏感,酸溶液浸泡后強度下降達17.5%;(4)復合連接接頭在受壓變形過程中完好無損,證明了該連接的可靠性;壓縮變形中,熱縮帶和PE管材的應變較大,鋼帶應變小,且從30°位置到90°位置逐漸增大,最大應變出現(xiàn)在接頭的兩側。
[Abstract]:In recent years, polyethylene pipes have been widely used in municipal engineering. These two kinds of connection modes are simple in operation, fast in connection speed, good in connection effect and low in cost. However, there are many defects in the two connection modes when they are used separately, and the reliability of connection is relatively insufficient. In this project, the composite application of the two methods is studied in order to obtain the excellent effect of the integrated connection. At present, there are very few cases in which the two methods are used together in municipal engineering, so there is no construction operation guide and acceptance standard for the combined application of hot shrinkage zone and hot melt extrusion welding, let alone systematic and complete technical regulations. From the literature, there is hardly any research result of combining the two methods. Therefore, it is necessary to further study the composite operation technology of the two kinds of connection methods and the effect of composite connection. Testing and evaluating methods for durability and composite properties. This paper relies on the joint connection research project of plastic steel winding drainage pipe of the 7th Bureau of Water Conservancy and Hydropower of China. In view of the above problems, from the raw material test analysis, the composite connection process design, The performance tests and full-scale joint tests of combined joint specimens are studied systematically. The main contents and results are as follows: (1) the basic properties of PE joint materials are tested. On the basis of this, the relationship between the flame height, the walking speed and the bonding temperature of the hot necking belt is determined. And the relationship between bonding temperature and bond strength. Based on the comprehensive analysis of the flame height, the walking speed, the bonding temperature and the bonding strength of the spray gun, the paper puts forward the heating process parameters of the hot shrinkage belt connection: the suitable heating flame height is about 15cm. The suitable walking speed of heating flame is 1 0cm/s~12.5cm/s, and the control temperature is 110 鈩，

本文編號：2424711