鉛管因質軟且重,故經(jing)過搬運(yun)、裝卸(xie)之后一般均產生變形(xing),所以鉛管在安(an)裝前(qian)均應調(diao)直和校圓。 


  鉛(qian)(qian)管(guan)調(diao)直時,鉛(qian)(qian)管(guan)應放在鋪有木(mu)板的(de)平臺上用木(mu)榔頭輕輕敲打調(diao)直。為了便于檢(jian)査和(he)操作,常把鉛(qian)(qian)管(guan)緊貼在角(jiao)鋼或槽鋼內(nei)側的(de)翼上,根(gen)據管(guan)子和(he)型鋼的(de)間隙拍打調(diao)直。


  鉛(qian)(qian)管(guan)(guan)(guan)除(chu)調直外,還需校圓(yuan)。直徑大于DN50mm的(de)鉛(qian)(qian)管(guan)(guan)(guan)校圓(yuan),可用(yong)一根外徑小于鉛(qian)(qian)管(guan)(guan)(guan)內徑的(de)鋼管(guan)(guan)(guan)(管(guan)(guan)(guan)端(duan)最(zui)好制成一半球形封(feng)頭)穿在鉛(qian)(qian)管(guan)(guan)(guan)內,并把鋼管(guan)(guan)(guan)的(de)兩端(duan)放(fang)在支(zhi)撐架(jia)上, 然后用(yong)木錘敲打鉛(qian)(qian)管(guan)(guan)(guan)被壓扁(bian)的(de)地方,邊(bian)(bian)打邊(bian)(bian)轉(zhuan)動管(guan)(guan)(guan)子,直到將管(guan)(guan)(guan)子校圓(yuan)為止。


  鉛(qian)管校(xiao)圓的(de)方法還有用(yong)硬(ying)木制成的(de)外徑與鉛(qian)管內(nei)徑相(xiang)同的(de)圓柱形胎(tai)具,將(jiang)頭部削圓, 穿上繩子,用(yong)繩將(jiang)胎(tai)具拉進(jin)管內(nei),使變形部位隨胎(tai)具而撐圓。


  鉛(qian)管(guan)直(zhi)徑不大于DN50mm的(de)鉛(qian)管(guan)校(xiao)圓,可(ke)將鉛(qian)管(guan)兩(liang)端堵塞,在管(guan)內(nei)通入壓(ya)力為(wei)0.3~0.4MPa的(de)壓(ya)縮(suo)(suo)空氣,然后用(yong)焊(han)炬對壓(ya)扁(bian)的(de)地(di)方(fang)加熱(re)(re),管(guan)內(nei)的(de)壓(ya)縮(suo)(suo)空氣把管(guan)子脹(zhang)圓,加熱(re)(re)時,要注意使加熱(re)(re)部分受(shou)熱(re)(re)均勻,升溫不要太快,當(dang)管(guan)子被脹(zhang)圓時,應立即停止(zhi)加熱(re)(re)。