本文關鍵詞： 灰口鑄鐵管 腐蝕結垢 三維掃描 數(shù)值模擬 應力計算　出處：《浙江大學》2013年碩士論文　論文類型：學位論文

【摘要】：灰口鑄鐵管曾作為城市給水系統(tǒng)中的主要管材被大量使用于我國的城鎮(zhèn)給水管網(wǎng)中,雖然截至2012年,灰口鑄鐵管已經(jīng)被禁止使用于給水系統(tǒng)中,但是據(jù)不完全統(tǒng)計我國現(xiàn)仍有51%灰口鑄鐵管在給水管網(wǎng)中服役。由于灰口鑄鐵管本身的材質原因,在使用一段時間后,灰口鑄鐵管內(nèi)壁會發(fā)生腐蝕,形成腐蝕坑；同時腐蝕產(chǎn)物沉淀、粘結于管道內(nèi)壁形成管垢。管道的腐蝕會使管壁變薄降低管道強度、腐蝕產(chǎn)物的溶解污染了管內(nèi)飲用水、管壁結垢導致管道內(nèi)過水斷面面積減小減弱了管道的輸水能力�；铱阼T鐵管腐蝕結垢所帶來的水質污染問題、管網(wǎng)安全問題及供水保障問題已經(jīng)嚴重威脅到了每一個用水者的切身利益。 針對現(xiàn)階段我國供水系統(tǒng)中由灰口鑄鐵管所引起的各類問題較為頻繁這一實際情況出發(fā),本文中以杭州市供水管網(wǎng)中的一段管齡為15年的灰口鑄鐵管管段作為研究對象,采用化學分析的方法對灰口鑄鐵管內(nèi)壁腐蝕結垢瘤進行淺析；借助三維掃描建模技術,將灰口鑄鐵管內(nèi)壁形態(tài)進行了數(shù)字化還原；通過對模型中腐蝕坑洞的測量統(tǒng)計,得到了管道內(nèi)壁腐蝕瘤(坑)的分布情況與形態(tài)大�。蛔詈蟛捎糜嬎銠C數(shù)值模擬的方法在不考慮土體荷載與約束的情況下對灰口鑄鐵管管內(nèi)流態(tài)情況、管道內(nèi)受力等情況進行了模擬研究；結合腐蝕管道剩余強度理論,采用數(shù)值計算的方法得出腐蝕后灰口鑄鐵管的剩余強度值；以灰口鑄鐵管的剩余強度值和模擬研究的結果作為基礎,判斷了管段是否安全。 研究結果表明：灰口鑄鐵管內(nèi)壁的腐蝕結垢起始于金屬的電化學腐蝕,管垢的主要成分是：鐵、氧、鋁、硅、硫、碳。其中鐵和氧的成分比例占到了管垢的90%。管內(nèi)水垢主要是由腐蝕沉積物組成,形態(tài)以凸起的瘤狀為主,腐蝕瘤尺寸差異較大,在管內(nèi)無規(guī)則分布；這些形態(tài)各異的腐蝕沉積物的不規(guī)則分布,導致了管道內(nèi)流體的流態(tài)紊亂、管內(nèi)壓力和流速分布不均,對供水管網(wǎng)造成水頭損失增加、供水不足及能源浪費；管道在腐蝕破壞后,管道僅在內(nèi)壓的作用下極易在腐蝕坑洞處形成應力集中,應力集中點的Mises應力大小甚至能達到管道內(nèi)壓的數(shù)倍,同時腐蝕破壞帶來的管道的剩余強度衰減也降低了管道使用過程中的安全系數(shù)。 本論文得到了水體污染控制與治理科技重大專項課題：“典型城市飲用水安全保障共性技術研究與示范(編號：2008ZX07424)".'‘潮汐影響地區(qū)飲用水安全保障技術集成與示范”(編號：2008ZX07424-001)和“山地丘陵城市飲用水安全保障共性技術研究與示范”(編號：2008ZX07424-004)的資助。
[Abstract]:Gray cast iron pipes have been widely used in urban water supply networks in China, although as of 2012, gray cast iron pipes have been banned from being used in water supply systems. However, according to incomplete statistics, there are still 51% gray cast iron pipes in service in water supply pipe network in China. Due to the material reason of gray cast iron pipe itself, the inner wall of gray cast iron pipe will be corroded and corrosion pit will be formed after using for a period of time. At the same time, corrosion products precipitate and form pipe scale by sticking to the inner wall of the pipe. The corrosion of the pipe will make the pipe wall thinning and reduce the strength of the pipe, and the dissolution of the corrosion product will pollute the drinking water in the pipe. The fouling of the pipe wall leads to the reduction of the cross section area of the pipeline, which weakens the water delivery capacity of the pipeline. The water pollution caused by the corrosion and scaling of the gray cast iron pipe, The problem of pipe network safety and water supply security has seriously threatened the vital interests of every water user. In view of the fact that all kinds of problems caused by gray cast iron pipe are more frequent in the water supply system of our country at present, this paper takes a section of gray cast iron pipe in Hangzhou water supply network as the research object. Chemical analysis method is used to analyze the corrosion and scaling of the inner wall of gray cast iron pipe; with the help of 3D scanning modeling technology, the shape of inner wall of gray cast iron pipe is digitally reduced. The distribution and shape of corrosion nodule (pit) in the inner wall of pipeline are obtained. Finally, the internal flow state of gray cast iron pipe is simulated by computer numerical simulation method without considering the soil load and constraint. Based on the theory of residual strength of corroded pipeline, the residual strength of corroded gray cast iron pipe is obtained by numerical calculation. Based on the residual strength of gray cast iron pipe and the result of simulation study, the safety of pipe section is judged. The results show that the corrosion and scaling of the inner wall of gray cast iron pipe begin with the electrochemical corrosion of metal. The main components of the scale are: iron, oxygen, aluminum, silicon, sulfur, etc. Carbon. The proportion of iron and oxygen is 90% of the scale in the tube. The scale in the tube is mainly composed of corroded sediment, which is mainly shaped by bulge, and the size of the corrosion tumor varies greatly, and it is not distributed regularly in the tube. The irregular distribution of these corrosion sediments in different shapes leads to the fluid flow disorder in the pipeline, the uneven distribution of pressure and velocity in the pipe, the increase of water head loss, the shortage of water supply and the waste of energy. After the pipeline is corroded and destroyed, it is easy to form stress concentration in the corrosion pit under the action of only internal pressure. The Mises stress at the stress concentration point can even reach several times of the internal pressure of the pipeline. At the same time, the residual strength attenuation of pipeline caused by corrosion damage also reduces the safety factor in the process of pipeline operation. In this paper, a major scientific and technological project on water pollution control and control has been obtained: "study and demonstration of common technologies for drinking water safety assurance in typical cities (No.: 2008ZX0742424)" .integration and demonstration of drinking water security technology in tidal affected areas (. Number: 2008ZX07424-001) and "Research and demonstration of common technologies for the safety of drinking water in hilly cities" (No.: 2008ZX07424-004).
【學位授予單位】：浙江大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：TU991.33

【參考文獻】

相關期刊論文 前10條

1 李正印;劉志攀;何智勇;;供水系統(tǒng)中水垢形成機理探討[J];廣東化工;2008年09期

2 鄭小明;姚黎光;宋仁元;;上海供水管網(wǎng)概況、問題及對策[J];供水技術;2007年04期

3 馮文昌;給水系統(tǒng)的腐蝕及控制[J];中國給水排水;1992年01期

4 廖麗妃;胡學香;胡春;趙丹;;供水管網(wǎng)管垢的特征及其對水質的影響研究[J];中國給水排水;2011年15期

5 米子龍;張曉健;陳超;陸品品;汪雋;顧軍農(nóng);;硫酸根和堿度變化對管網(wǎng)鐵釋放的影響[J];中國給水排水;2012年01期

6 吳紅偉,劉文君,賀北平,王占生,張彌,樊康平;配水管網(wǎng)中管垢的形成特點和防治措施[J];中國給水排水;1998年03期

7 王立清,欒秀全;給水管道水垢形成及處理方法小議[J];哈爾濱鐵道科技;2002年03期

8 盛銘軍;王秀英;;城市管網(wǎng)生長環(huán)物質組成研究分析[J];工業(yè)用水與廢水;2006年03期

9 牛璋彬;王洋;張曉健;何文杰;韓宏大;陰沛軍;;給水管網(wǎng)中管內(nèi)壁腐蝕管垢特征分析[J];環(huán)境科學;2006年06期

10 牛璋彬;王洋;張曉健;陳超;王生輝;;給水管網(wǎng)中鐵釋放現(xiàn)象的影響因素研究[J];環(huán)境科學;2007年10期

，

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