鉛管因質軟且重,故(gu)經過搬運、裝(zhuang)(zhuang)卸(xie)之后一般均(jun)產生變形,所以鉛管在安裝(zhuang)(zhuang)前均(jun)應調直和校圓。 


  鉛(qian)管(guan)調(diao)直時,鉛(qian)管(guan)應放在鋪有木板的(de)平臺上(shang)用木榔頭輕(qing)輕(qing)敲打調(diao)直。為了便于檢査和操作,常把鉛(qian)管(guan)緊(jin)貼(tie)在角鋼(gang)或槽鋼(gang)內側的(de)翼(yi)上(shang),根據管(guan)子(zi)和型(xing)鋼(gang)的(de)間隙(xi)拍打調(diao)直。


  鉛(qian)管(guan)(guan)(guan)(guan)(guan)除調直外,還需校(xiao)圓(yuan)。直徑大于DN50mm的(de)(de)(de)鉛(qian)管(guan)(guan)(guan)(guan)(guan)校(xiao)圓(yuan),可用一(yi)根(gen)外徑小于鉛(qian)管(guan)(guan)(guan)(guan)(guan)內(nei)(nei)徑的(de)(de)(de)鋼管(guan)(guan)(guan)(guan)(guan)(管(guan)(guan)(guan)(guan)(guan)端(duan)(duan)最好(hao)制成一(yi)半球形(xing)封頭)穿在鉛(qian)管(guan)(guan)(guan)(guan)(guan)內(nei)(nei),并把鋼管(guan)(guan)(guan)(guan)(guan)的(de)(de)(de)兩端(duan)(duan)放在支撐架上(shang), 然后用木錘敲打鉛(qian)管(guan)(guan)(guan)(guan)(guan)被(bei)壓扁(bian)的(de)(de)(de)地方,邊打邊轉(zhuan)動(dong)管(guan)(guan)(guan)(guan)(guan)子,直到將管(guan)(guan)(guan)(guan)(guan)子校(xiao)圓(yuan)為止。


  鉛(qian)管校(xiao)圓(yuan)(yuan)的方法還(huan)有用(yong)硬木制成的外(wai)徑與鉛(qian)管內(nei)徑相同(tong)的圓(yuan)(yuan)柱形(xing)胎具,將(jiang)頭部(bu)(bu)削圓(yuan)(yuan), 穿上繩子,用(yong)繩將(jiang)胎具拉(la)進管內(nei),使變形(xing)部(bu)(bu)位隨(sui)胎具而撐(cheng)圓(yuan)(yuan)。


  鉛管(guan)直徑不(bu)大于DN50mm的(de)鉛管(guan)校圓(yuan),可(ke)將鉛管(guan)兩(liang)端堵(du)塞,在管(guan)內(nei)通入壓力為0.3~0.4MPa的(de)壓縮(suo)空氣,然后用焊炬對壓扁的(de)地方加熱,管(guan)內(nei)的(de)壓縮(suo)空氣把(ba)管(guan)子脹圓(yuan),加熱時(shi),要(yao)(yao)注意使加熱部(bu)分受熱均勻(yun),升溫不(bu)要(yao)(yao)太(tai)快(kuai),當(dang)管(guan)子被脹圓(yuan)時(shi),應立即停止(zhi)加熱。