管道工程中常用的有色金屬(Non-ferrous Metal)有銅(tong)、鋁、鉛和鋅等。


1. 銅(Copper)


  銅(tong)(tong)(tong)(tong)又(you)分純銅(tong)(tong)(tong)(tong)(俗稱紫銅(tong)(tong)(tong)(tong))、黃銅(tong)(tong)(tong)(tong)和青銅(tong)(tong)(tong)(tong)等。有關銅(tong)(tong)(tong)(tong)管的(de)標準規(gui)范包括 ASTM B42、ASTM B43、ASTM B315、ASTM B466、ASTM B467,有關銅(tong)(tong)(tong)(tong)管件的(de)標準規(gui)范有ASMEB16.24、ASME B16.22、ASME B16.15、ASME B16.18等。


 a. 純銅(Copper)


    純(chun)(chun)銅呈紫紅色(se),有良好的導電性(xing)、導熱性(xing)和耐大氣腐蝕性(xing),熔點為1083℃。在(zai)(zai)管(guan)道(dao)工程中(zhong)常用純(chun)(chun)銅制(zhi)成鋼管(guan)和法蘭(lan)墊片。因純(chun)(chun)銅硬(ying)度(du)較低,退火后變(bian)得(de)更柔軟,故(gu)常用來(lai)制(zhi)作(zuo)高(gao)壓(ya)管(guan)道(dao)中(zhong)   的法蘭(lan)墊片。純(chun)(chun)銅管(guan)的低溫(wen)性(xing)能(neng)比鋼材好,故(gu)純(chun)(chun)銅管(guan)常用于空分(fen)設備管(guan)道(dao)、冷凍管(guan)道(dao)和儀表管(guan)道(dao)。純(chun)(chun)銅的高(gao)溫(wen)性(xing)能(neng)差,在(zai)(zai)120℃以(yi)下,允許(xu)抗拉(la)強度(du)為29.43MPa。溫(wen)度(du)若再升(sheng)高(gao),其機械強度(du)則急劇下降,當溫(wen)度(du)上升(sheng)至250℃時,其允許(xu)抗拉(la)強度(du)只相當于常溫(wen)時的2/3,已不宜在(zai)(zai)壓(ya)力下使用。


    常用(yong)的純(chun)銅(tong)牌號為T2、T3、T4,雜質含(han)量(liang)T2最(zui)少(shao),T4最(zui)多(duo)。


  b. 黃銅(tong)(Brass)


   黃(huang)銅是銅和(he)鋅的(de)合金,其機械(xie)強(qiang)度(du)高,有較好(hao)的(de)耐腐蝕性和(he)澆(jiao)鑄性,可用(yong)來(lai)制作管子、管件和(he)閥門等。化(hua)工上常用(yong)的(de)有H80、H68、H62(“H”是黃(huang)銅代號,后邊的(de)數字表示合金中(zhong)銅的(de)平均含量)。H80比(bi)H68塑性好(hao)。進行強(qiang)度(du)計算(suan)時,在120℃以下,黃(huang)銅允許(xu)抗拉強(qiang)度(du)為29.43MPa。隨著溫度(du)升高,其強(qiang)度(du)則急劇下降,當(dang)溫度(du)未超(chao)過225℃時,黃(huang)銅閥件可用(yong)在壓(ya)力不(bu)超(chao)過1.6MPa的(de)管道中(zhong)。


  c. 青銅(tong)(Bronze)


    青(qing)(qing)銅(tong)是銅(tong)和錫的合金(jin),又稱錫青(qing)(qing)銅(tong)。由于(yu)(yu)錫的價格較高,故制造青(qing)(qing)銅(tong)也常(chang)用其(qi)他元(yuan)素代(dai)替,因(yin)而(er)又有(you)無錫青(qing)(qing)銅(tong),如鋁青(qing)(qing)銅(tong)、鉛青(qing)(qing)銅(tong)、硅青(qing)(qing)銅(tong)等。青(qing)(qing)銅(tong)通(tong)常(chang)由澆鑄(zhu)而(er)成,其(qi)強度、硬度及(ji)耐(nai)腐蝕(shi)性都比黃銅(tong)好。青(qing)(qing)銅(tong)常(chang)用于(yu)(yu)制造蝸輪(lun)(lun)、齒輪(lun)(lun)、輪(lun)(lun),以及(ji)管道工(gong)程中的閥件(jian)和管件(jian)等。



2. 鋁(Aluminum)


  鋁(lv)(lv)的熔點為527℃,它具有良(liang)好的導熱(re)性(xing)和(he)導電(dian)性(xing),強度(du)(du)和(he)硬(ying)度(du)(du)較(jiao)低,可(ke)塑性(xing)好。鋁(lv)(lv)容(rong)易氧化,在空氣中,鋁(lv)(lv)的表(biao)面能形成一層極薄(bo)的氧化鋁(lv)(lv)保護膜(mo),防止繼續氧化。鋁(lv)(lv)合金薄(bo)板(ban)常作為壓力管道絕熱(re)工程(cheng)的管子、塔、罐(guan)、換(huan)熱(re)器(qi)、閥門、法蘭以及其(qi)他(ta)平壁設備保護層材料(liao)。


  純鋁(lv)的(de)強度和(he)(he)硬度雖然(ran)很低(di),但若加(jia)入其他(ta)元素可以提高。鋁(lv)合(he)(he)金分為(wei)鑄造鋁(lv)合(he)(he)金和(he)(he)可壓迫變形的(de)鋁(lv)合(he)(he)金兩大類(lei)。管(guan)道工程中,常(chang)用L2和(he)(he)L3牌號的(de)鋁(lv)管(guan)輸送硝酸和(he)(he)醋(cu)酸等,但是鋁(lv)不(bu)能抵抗堿性腐蝕。當溫度高于(yu)150℃時,鋁(lv)管(guan)不(bu)宜用于(yu)壓力(li)管(guan)道。鋁(lv)和(he)(he)鋁(lv)合(he)(he)金管(guan)的(de)標(biao)準規范有ASTM B241、ASTM B26、ASTM B108、ASTM B209、ASTM B210、ASTM B211、ASTM


  B221、ASTMI B234、ASTM B247 以及(ji) ASME B31.3的“附(fu)錄L-鋁合(he)金管法蘭”。


3. 鉛(Lead)


  鉛(qian)(qian)是一種(zhong)暗(an)灰色的(de)(de)金屬,熔點為327℃,它有很(hen)好的(de)(de)耐(nai)腐蝕性(xing)能,常用(yong)(yong)(yong)來(lai)制作硫酸設(she)備和(he)管(guan)(guan)道(dao)襯里。鉛(qian)(qian)質軟,可(ke)塑性(xing)好,管(guan)(guan)道(dao)工程中(zhong)常用(yong)(yong)(yong)鉛(qian)(qian)管(guan)(guan)。在安(an)裝鑄(zhu)鐵管(guan)(guan)承插口時(shi)(shi),常用(yong)(yong)(yong)鉛(qian)(qian)作為接口填塞材(cai)料(liao),以牌號為Pb-6的(de)(de)鉛(qian)(qian)較(jiao)適(shi)宜。硬鉛(qian)(qian)是鉛(qian)(qian)和(he)銻的(de)(de)合金,它的(de)(de)抗(kang)腐蝕性(xing)略低于(yu)純鉛(qian)(qian),但機(ji)械強度(du)較(jiao)高(gao),常用(yong)(yong)(yong)于(yu)制造(zao)耐(nai)酸設(she)備。鉛(qian)(qian)蒸氣(qi)有毒,故熔化鉛(qian)(qian)時(shi)(shi),要(yao)防(fang)止燙(tang)傷和(he)鉛(qian)(qian)中(zhong)毒。在化工行(xing)業中(zhong),鉛(qian)(qian)主(zhu)要(yao)用(yong)(yong)(yong)在處理硫酸的(de)(de)設(she)備上。Pb-4用(yong)(yong)(yong)于(yu)設(she)備內襯,Pb-6用(yong)(yong)(yong)于(yu)管(guan)(guan)道(dao)接頭,硬鉛(qian)(qian)可(ke)制造(zao)硫酸工業用(yong)(yong)(yong)的(de)(de)泵、閥(fa)門、管(guan)(guan)道(dao)等。


4. 鋅(Zinc)


  鋅(xin)(xin)呈淺灰色,熔點(dian)為419℃,它(ta)有(you)較(jiao)好的耐腐蝕性和力學性能(neng)(neng)。有(you)些鋼管和管件為增強耐腐蝕性能(neng)(neng),常(chang)在表(biao)面鍍一層(ceng)鋅(xin)(xin),如室內給水工程中常(chang)用(yong)的鍍鋅(xin)(xin)管。