預熱保溫爐

      臥式爐的爐底面(mian)比立(li)式爐的爐底面(mian)容易(yi)搗(dao)固(gu)，因為金屬(shu)熔(rong)溝基本上是平放著，僅僅略帶傾斜，這有(you)利于用鐵扦將石(shi)英砂(sha)搗(dao)結實。

      臥式爐熔(rong)(rong)(rong)溝(gou)(gou)(gou)安放(fang)(fang)要呈傾斜狀(zhuang)，不應(ying)完(wan)金(jin)(jin)(jin)平(ping)(ping)放(fang)(fang)，傾斜度(du)約18。，因為(wei)完(wan)全(quan)平(ping)(ping)放(fang)(fang)不利于(yu)液(ye)體金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)的熱(re)(re)(re)(re)循(xun)環，感應(ying)電(dian)爐中(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)的運動，不只是(shi)由于(yu)電(dian)磁現(xian)象所引起(qi)的，同時(shi)也(ye)為(wei)熱(re)(re)(re)(re)現(xian)象所引起(qi)，因為(wei)熱(re)(re)(re)(re)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)與冷金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)的比重不一樣，過熱(re)(re)(re)(re)的金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)是(shi)位于(yu)熔(rong)(rong)(rong)溝(gou)(gou)(gou)后(hou)面狹帶(dai)部份，較冷的金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)則在(zai)熔(rong)(rong)(rong)溝(gou)(gou)(gou)的前而和與熔(rong)(rong)(rong)溝(gou)(gou)(gou)相連(lian)的熔(rong)(rong)(rong)池內(nei)，這(zhe)(zhe)樣就(jiu)能引起(qi)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)的熱(re)(re)(re)(re)循(xun)環，從而使(shi)熔(rong)(rong)(rong)池內(nei)的金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)逐漸得(de)到(dao)升熱(re)(re)(re)(re)。如果將熔(rong)(rong)(rong)溝(gou)(gou)(gou)完(wan)全(quan)平(ping)(ping)放(fang)(fang)，實踐證明將使(shi)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)加(jia)熱(re)(re)(re)(re)時(shi)間(jian)延長，從現(xian)象上(shang)也(ye)能看到(dao)，在(zai)加(jia)熱(re)(re)(re)(re)過程中(zhong)，電(dian)流(liu)表上(shang)的指(zhi)針產生不停地搖擺(bai)，這(zhe)(zhe)種現(xian)象的產生說明了(le)(le)熔(rong)(rong)(rong)溝(gou)(gou)(gou)內(nei)的金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)導(dao)體在(zai)不停地發生瞬息斷路，于(yu)是(shi)使(shi)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)加(jia)熱(re)(re)(re)(re)放(fang)(fang)慢了(le)(le)速度(du)，將熔(rong)(rong)(rong)溝(gou)(gou)(gou)呈傾斜狀(zhuang)安放(fang)(fang)，則能改善(shan)熱(re)(re)(re)(re)循(xun)環條件(jian)，從而加(jia)快(kuai)金(jin)(jin)(jin)屬(shu)(shu)(shu)(shu)的加(jia)熱(re)(re)(re)(re)。

      筑爐安放(fang)(fang)熔(rong)溝(gou)時(shi)，在實(shi)際操作中(zhong)必須使用量具來求取(qu)傾斜(xie)角度(du)，只要在擱(ge)放(fang)(fang)熔(rong)溝(gou)前(qian)部時(shi)，砌(qi)兩層(ceng)斧(fu)形磚(zhuan)，將熔(rong)溝(gou)安放(fang)(fang)在斧(fu)形磚(zhuan)的(de)斜(xie)面上(shang)，即能(neng)達到傾斜(xie)度(du)的(de)要求，非(fei)常簡便。

      能使保溫爐內的液體金屬直接進入結晶器內，是依靠裝置在爐身前墻內的石墨底座，實際上石墨底座既是金屬的流出口，又足使爐子與結晶器的連接器，一端伸入熔池內，在金屬流出口上安裝一個石墨制塞桿，旋開石墨塞桿，液體金屬便從石墨底座的管道流入與之相連的結晶器內，將石墨塞桿旋緊，液體金屬被堵住不能外流，另一端被埋在前墻爐壁內，用一塊外方內圓有錐度的耐火磚使其位置固定。

       應當(dang)指出，石(shi)(shi)墨底座在砌爐時不能(neng)完全埋在石(shi)(shi)英砂中(zhong)，應使其體積的一半(ban)露出石(shi)(shi)英砂底使它(ta)泡在熔融金屬中(zhong)和金屬一同加(jia)熱，實(shi)踐證明，石(shi)(shi)墨底座完全或絕大部份被(bei)埋在石(shi)(shi)英砂內，當(dang)金屬流(liu)入結晶器之前(qian)，就有被(bei)降低溫度(du)而影響拉鑄。