本文選題：有限元分析 + 倉泵��； 參考：《電子科技大學(xué)》2011年碩士論文

【摘要】：倉泵多數(shù)在高溫高壓下運(yùn)行,是壓送式氣力輸送粉末狀物料(如水泥、礦粉、粉煤灰、糧食、化工原料)的理想設(shè)備。因此,倉泵的焊接接頭必須具有較高的強(qiáng)度、耐磨性,足夠高的沖擊韌性和較高的耐熱性,并且保證接頭無裂紋、末熔合、夾渣等缺陷。本課題研究的倉泵是浙江菲達(dá)環(huán)保集團(tuán)公司生產(chǎn)低壓容器中的一個主要品種,是氣力輸送環(huán)保配套設(shè)備的關(guān)鍵部件,其殼體母材是15CrMoR鋼。解決15CrMoR鋼焊后冷裂紋問題以獲得強(qiáng)度高、韌性與塑性好的優(yōu)質(zhì)倉泵焊接接頭成為倉泵生產(chǎn)制造過程中的關(guān)鍵問題。 本論文通過對倉泵殼體15CrMoR鋼的化學(xué)成分和性能分析、焊接裂紋敏感性計(jì)算、裂紋敏感機(jī)理分析及焊接工藝可行性分析,結(jié)合生產(chǎn)實(shí)際,確定了課題研究目標(biāo)是以MAG氣體保護(hù)焊打底、填充,埋弧焊蓋面的組合焊法為重點(diǎn)研究內(nèi)容。采用ANSYS系統(tǒng)對倉泵焊接溫度場和焊接應(yīng)力場進(jìn)行動態(tài)模擬,建立了基于ANSYS軟件系統(tǒng)溫度場、應(yīng)力場的有限元分析模型,針對不同時刻焊接溫度場分布,焊接應(yīng)力場中殘余應(yīng)力的變化進(jìn)行了數(shù)字分析,為16mm中厚板多層多道焊選擇焊接規(guī)范提供了科學(xué)依據(jù)。 在倉泵焊接應(yīng)用研究中,我們采用了不同的預(yù)熱溫度、焊接電流、焊接速度及線能量進(jìn)行施焊,對焊接接頭焊縫進(jìn)行X射線探傷,力學(xué)性能試驗(yàn),達(dá)到JB4730-2005《承壓設(shè)備無損檢測》標(biāo)準(zhǔn)中的Ⅱ級要求,焊縫外觀達(dá)到GB50236-98《現(xiàn)場設(shè)備、工業(yè)管道焊接工程施工及驗(yàn)收規(guī)范》標(biāo)準(zhǔn)中的Ⅰ級要求。通過對接頭金相組織進(jìn)行分析,焊縫組織為細(xì)小的柱狀晶,而熔合區(qū)和熱影響區(qū)組織均為柱狀晶鐵素體+粒狀貝氏體+低碳馬氏體組織。研究結(jié)果表明:倉泵焊接填充材料是H13CrMoA ,要求焊前預(yù)熱溫度為150～180℃,打底層、填充層MAG氣體保護(hù)焊保護(hù)介質(zhì)為20%CO2+80%Ar,電弧電壓為22±1V,焊接電流為130～170A。埋弧焊進(jìn)行蓋面,焊接電流為480～550,電弧電壓為36～38V。焊后熱處理溫度為250℃,保溫lh,正火溫度900℃,保溫1h后馬上隨爐冷卻,采用焊后熱處理方式,高溫回火溫度為680士100℃,保溫1h。得到的焊接接頭抗拉強(qiáng)度為560Mpa,焊縫金屬(20℃)沖擊韌性為79J,完全可以滿足倉泵設(shè)計(jì)的技術(shù)要求。 通過本次應(yīng)用研究分析,焊接熱輸入對接頭組織和性能有重大影響,通過調(diào)整熱輸入能有效控制接頭冷卻速度,從而改善熱影響區(qū)的脆化和軟化現(xiàn)象,提高接頭的強(qiáng)度、韌性,滿足了產(chǎn)品的設(shè)計(jì)制造要求。 本文倉泵焊接的應(yīng)用研究已用于產(chǎn)品焊接生產(chǎn),焊接質(zhì)量達(dá)到了相應(yīng)國家標(biāo)準(zhǔn)規(guī)定要求。
[Abstract]:Most of the storage pumps operate at high temperature and high pressure. They are ideal equipment for pneumatic conveying of powder materials (such as cement, mineral powder, fly ash, grain and chemical raw materials). Therefore, the welded joints of bin pump must have high strength, wear resistance, high impact toughness and high heat resistance, and ensure that the joints are free of cracks, end fusion, slag inclusion and other defects. The storage pump studied in this paper is one of the main varieties of low pressure vessels produced by Zhejiang Fida Environmental Protection Group Co., Ltd. It is the key part of the supporting equipment for pneumatic transportation and environmental protection. Its shell base material is 15CrMoR steel. To solve the problem of cold crack after welding of 15CrMoR steel to obtain high strength, good toughness and good ductility, the welding joint of high quality warehouse pump becomes the key problem in the production and manufacture of warehouse pump. In this paper, the chemical composition and properties of 15CrMoR steel, the calculation of welding crack sensitivity, the mechanism of crack sensitivity and the feasibility of welding process are analyzed. The research object is focused on MAG gas shielded welding, filling and combined welding of submerged arc welding cover. The welding temperature field and welding stress field of warehouse pump are simulated dynamically by ANSYS system, and the finite element analysis model of temperature field and stress field based on ANSYS software system is established, aiming at the distribution of welding temperature field at different time. The variation of residual stress in welding stress field is analyzed numerically, which provides a scientific basis for the selection of welding specification for multi-layer and multi-pass welding of 16mm plate. In the research on the application of bin pump welding, we used different preheating temperature, welding current, welding speed and line energy to weld the welded joint. The welding seam was tested by X ray and mechanical properties. It can meet the requirements of Class 鈪，

本文編號：1789289