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輔助原料 輔助原料的用量較少,主要以改善玻璃的熔化、澄清和成型性能或使產品具有某些特殊性能,使玻璃獲得某些必要的性能和加速熔制過程的原料。三氧化銻為白色結晶粉末。%~1%,硝酸鹽的用量是氧化銻用量的4~8倍。浮法玻璃常用離子著色劑,即過渡金屬元素和稀土金屬元素的化合物。這些雜質主要來源是玻璃原料中含有的鐵、鉻、鈦、釩等化合物和有機物的有害雜質。采用脫色方法并不能從根本上消除著色源,尤其浮法玻璃成型是在弱還原氣氛中進行。碳粉的主要成分是C,它能降低Na2SO4的分解溫度。應當引起注意的是,還原劑的用量還依賴于各種原料,尤其是硅砂中的有機物含量(還原性物質)。當碎玻璃加入量合適時,碎玻璃的助熔作用使玻璃熔體粘度降低,縮短澄清和均化時間。根據浮法玻璃成型工藝的特點和要求,與普通平板玻璃相比,浮法玻璃成分中Al2O3的含量要適當?shù)臏p少,%;而CaO和MgO的總含量可以適當增加,等于或略大于12%;Na2O+K2O可以在14%左右;%以下,%,%。s;均勻流入的玻璃液在錫槽表面攤平并拋光,在經徐冷區(qū),溫度為850~900℃,~最后進入硬化區(qū),使玻璃硬化,進入退火窯而不變形。為此必須在成型溫度范圍內,使玻璃保持一定粘度與表面張力。s,相對應的溫度之間的溫差表示,即=()~()(1泊=浮法玻璃允許的析晶上限溫度(開始結晶溫度)應低于1025℃。玻璃的透明度高,可見光透射率達到國際要求以上。因此MgO控制在4%左右,以改善玻璃的析晶性能。根據Na2OCaOSiO2系統(tǒng)相圖確定系統(tǒng)中能夠形成玻璃的組成范圍:12%~18%Na2O;6%~16%CaO;68%~82%SiO2。表21中Fe2O3為原料中雜質所致,并非設計數(shù)值,而是限制數(shù)值;SO3主要是由澄清劑芒硝引入。進行配合料計算時,應認為原料中的氣體物質在加熱過程中全部分解逸出,而且分解后的氧化物全部轉入玻璃成分中。%~%之間。(4)螢石含率螢石含率指由螢石引入的CaF2量與原料引入總量之比,即螢石含率= (34)它隨熔化條件和碎玻璃的儲存量而增減,在正常情況下,一般在18%~26%。例如,在進行粗算時,在硅砂和砂巖含量中沒有考慮其他原料引入的SiO2和Al2O3,所以應進行校正。對配合料的主要要求是:(1)構成配合料的各種原料均應有一定的粒度組成,即同一種原料應有適宜的粒度,不同原料間保持一定的粒度比,以保證配合料的均勻度,熔制速度、玻璃液均勻度,提高混合質量,防止配合料的分層。 配合料制備的工藝流程浮法玻璃工廠原料大部分都必須經過破碎、篩分,而后經稱量、混合,最后制成配合料。砂巖、石英巖的硬度較大,用量也多,為了減少破碎時物料對機械設備的磨損,正常情況下應對其煅燒。破碎和粉碎的設備選型為:PE250400顎式破碎機:進料口尺寸:400mm250mm最大進料粒度:210mm產量:5~20t/d排料口調整范圍:20~60mm外形尺寸:1450mm1315mm1296mm電機功率:15kw2PG630300輾式破碎機:最大進料尺寸:10~25mm出料粒度:0~10mm生產率:2~8t/h輾子轉速:80r/min機重:電機功率:15kwPC800600錘式破碎機:給料粒度:300mm出料粒度:30mm產量:25~50t/h功率:55kw機重:2tLF600型籠形輾:生產能力:1~3t/h物料最大粒度:100mm主軸轉速:400r/min功率:外形尺寸:1200mm1450mm882mm機重: [1415] 原料的篩分各種塊狀原料經粉碎必須進行篩分,將雜質和大顆粒部分分離出去,使物料具有適宜的顆粒組成以保證配合料混合均勻和避免分層,不同的原料有不同的粒度要求,配合料中各原料應有一定的粒度比,難熔化的原料其粒度應適當細些。純堿、芒硝、石灰石、白云石,通過孔/cm2的篩。稱量必須做到準確無誤,否則會使玻璃的成分改變,這不僅會給玻璃的熔制和成型帶來一系列困難,而且還會影響制品的性能,造成制品的各種缺陷。而且如果混合的不夠完全,則玻璃制品中會出現(xiàn)條紋,氣泡及結石等缺陷。 原料運輸設備當被運輸?shù)奈锪纤骄嚯x較近,垂直高度較大時,可應用斗式提升機進行輸送。而且,由于玻璃工廠所用的原料大部分是粉粒狀的,因此,氣力輸送在玻璃工廠具有廣闊的前景。建廠全部投資:設備投資1200萬元;建筑物、構筑物投資2000萬元;設備運輸安裝按設備投資的20萬元;地皮費、車輛1000萬元;職工培訓20萬元。在本設計開始時,我查閱了大量的文獻資料,接觸到了當今最前沿的浮法玻璃技術,并借鑒了先進的科技支撐。由于我實在是能力有限,難免會存有不足和錯誤,希望各位老師能夠積極指教。在這里,感謝各位老師三年來的教導和幫助,謝謝你們的辛勤付出,謝謝你們。,30(5):2629[3] 王桂榮,浮法玻璃原料,北京:化學工業(yè)出版社,2006,30(5):7881[4] 陳樹正,浮法玻璃,武漢理工大學出版社,2002,26(7),5864[5]李春菊,胡濤,玻璃,維普資訊網,2006年第二期:6569[6]楊金剛,孫強,玻璃,維普資訊網,2004年第三期:3643[7]何峰,張兆艷,硅酸鹽學報,萬方數(shù)據庫,2003年第七期:3638[8]劉志強,玻璃,維普資訊網,2000年第二期:6769[9] 陳正樹.,浮法玻璃,武漢理工大學出版社,2008,168(5):49[10] 戴春梅. E 玻璃熔化過程中的物化反應和能量消耗[D] 大連理工大學 ,2008[11]鄭林義. 無機非金屬材料工廠設計概論 合肥工業(yè)大學,[12]宋曉嵐,葉昌,余海湖. 無機材料工藝學 冶金工業(yè)出版社,[13] 姜洪舟. 無機非金屬材料熱工設備( 第2 版) [M]武漢理工大學出版社,2009: 189 [14] 楊京安,彭壽. 浮法玻璃制造技術新工藝 化學工業(yè)出版社 [15] 構架質量技術監(jiān)督局 浮法玻璃 國家標準出版社 2002[16] Campos, I., Balankin, A., Bautista, O., Ram237。 fibrous posites are anisotropic, . their properties vary depending on the direction of the load with respect to the orientation of the fibres. Imagine a small sheet of balsa wood: it is much easier to bend (and break) it along a line parallel to the fibres than perpendicular to the fibres. This anisotropy is overe by stacking layers, each often only fractions of a millimetre thick, on top of one another with the fibres oriented at different angles to form a laminate.Except in very special cases, the laminate will still be anisotropic, but the variation in properties with respect to direction will be less extreme. In most aerospace applications, this approach is taken a stage further and the differently oriented layers (anything from a very few to several hundred in number) are stacked in a specific sequence to tailor the properties of the laminate to best withstand the loads to which it will be subjected. This way, material, and therefore weight, can be saved, which is a factor of prime importance in the aviation and aerospace industry.Another advantage of posite materials is that, generally speaking, they can be formed into more plex shapes than their metallic counterparts. This not only reduces the number of parts making up a given ponent, but also reduces the need for fasteners and joints, the advantages of which are twofold: fasteners and joints may be the weak points of a ponent — a bolt needs a hole which is a stress concentration and therefore a potential crackinitiation site, and fewer fasteners and joints can mean a shorter assembly time.Shorter assembly times, however , need to be offset against the greater time likely to be needed to fabricate the ponent in the first place. To produce a posite ponent, the individual layers, which are often preimpregnated (‘prepreg’) with the resin matrix, are cut to their required shapes, which are all likely to be different to a greater or lesser extent, and then stacked in the specified sequence over a former (the former is a solid or framed structure used to keep the uncured layers in the required shape prior to, and during, the curing process). This assembly is then subjected to a sequence of temeratures and pressures to‘cure’ the material. The product is then checked thoroughly to ensure both that dimensional tolerances are met and that the curing process has been successful (bubbles or voids in the laminate might have been formed as a result of contamination of the raw materials, for example).The Use of Composites in Aircraft Design Among the first uses of modern posite materials was about 30 years ago when boron reinforced epoxy posite was used for the skins of the empennages of the . F14 and F15 fighters. Initially, posite materials were used only in secondary structures, but as knowledge and development of the materials has improved, their use in primary structures such as wings and fuselages has increased. The following table lists some air craft in which significant amounts of posite materials are used in the airframe.Composites in Aerospace Applications Initially, the percentage by structural weight of posites used in manufacturing was very small, at around two percent in the F15, for example. However, the percentage has gr own considerably, through 19 percent in the F18 up to 24 percent in the F22