管(guan)道工程中常(chang)用的有色(se)金屬(Non-ferrous Metal)有銅、鋁、鉛和鋅等(deng)。


1. 銅(Copper)


  銅(tong)(tong)又分純(chun)銅(tong)(tong)(俗稱紫(zi)銅(tong)(tong))、黃銅(tong)(tong)和青(qing)銅(tong)(tong)等(deng)(deng)。有(you)關銅(tong)(tong)管(guan)的(de)標(biao)準規范包括 ASTM B42、ASTM B43、ASTM B315、ASTM B466、ASTM B467,有(you)關銅(tong)(tong)管(guan)件的(de)標(biao)準規范有(you)ASMEB16.24、ASME B16.22、ASME B16.15、ASME B16.18等(deng)(deng)。


 a. 純銅(Copper)


    純(chun)銅(tong)呈紫紅色,有良好(hao)的(de)導電性、導熱(re)性和耐大氣腐蝕性,熔(rong)點為(wei)1083℃。在管(guan)道(dao)工程中常(chang)(chang)(chang)用純(chun)銅(tong)制(zhi)成(cheng)鋼管(guan)和法蘭墊片。因純(chun)銅(tong)硬度(du)較(jiao)低,退火(huo)后變得更柔軟,故(gu)常(chang)(chang)(chang)用來制(zhi)作高(gao)(gao)壓管(guan)道(dao)中   的(de)法蘭墊片。純(chun)銅(tong)管(guan)的(de)低溫(wen)性能(neng)比鋼材好(hao),故(gu)純(chun)銅(tong)管(guan)常(chang)(chang)(chang)用于(yu)空分設備管(guan)道(dao)、冷凍管(guan)道(dao)和儀表管(guan)道(dao)。純(chun)銅(tong)的(de)高(gao)(gao)溫(wen)性能(neng)差,在120℃以下(xia),允許(xu)抗(kang)拉強(qiang)度(du)為(wei)29.43MPa。溫(wen)度(du)若再升(sheng)高(gao)(gao),其機械強(qiang)度(du)則急(ji)劇(ju)下(xia)降(jiang),當(dang)溫(wen)度(du)上升(sheng)至250℃時(shi),其允許(xu)抗(kang)拉強(qiang)度(du)只相當(dang)于(yu)常(chang)(chang)(chang)溫(wen)時(shi)的(de)2/3,已不(bu)宜在壓力下(xia)使用。


    常(chang)用的(de)純銅(tong)牌(pai)號為T2、T3、T4,雜質含(han)量T2最少(shao),T4最多。


  b. 黃銅(Brass)


   黃銅(tong)(tong)是銅(tong)(tong)和鋅(xin)的(de)合(he)(he)金(jin),其機械強(qiang)(qiang)度(du)高(gao),有較好的(de)耐腐蝕性(xing)(xing)和澆鑄性(xing)(xing),可用來(lai)制作管子(zi)、管件和閥門等(deng)。化(hua)工(gong)上常用的(de)有H80、H68、H62(“H”是黃銅(tong)(tong)代(dai)號,后邊的(de)數(shu)字表示合(he)(he)金(jin)中銅(tong)(tong)的(de)平均含量(liang))。H80比(bi)H68塑性(xing)(xing)好。進行強(qiang)(qiang)度(du)計算時,在120℃以(yi)下,黃銅(tong)(tong)允許抗拉強(qiang)(qiang)度(du)為29.43MPa。隨(sui)著溫度(du)升高(gao),其強(qiang)(qiang)度(du)則(ze)急劇下降(jiang),當溫度(du)未(wei)超過225℃時,黃銅(tong)(tong)閥件可用在壓力不(bu)超過1.6MPa的(de)管道(dao)中。


  c. 青銅(Bronze)


    青(qing)(qing)(qing)銅(tong)是銅(tong)和錫的合金,又稱錫青(qing)(qing)(qing)銅(tong)。由(you)于錫的價格較(jiao)高(gao),故制造(zao)青(qing)(qing)(qing)銅(tong)也常用(yong)其(qi)他元(yuan)素代替,因而(er)又有(you)無錫青(qing)(qing)(qing)銅(tong),如鋁青(qing)(qing)(qing)銅(tong)、鉛青(qing)(qing)(qing)銅(tong)、硅青(qing)(qing)(qing)銅(tong)等(deng)(deng)。青(qing)(qing)(qing)銅(tong)通常由(you)澆鑄(zhu)而(er)成(cheng),其(qi)強度、硬度及(ji)耐腐蝕(shi)性都比黃(huang)銅(tong)好(hao)。青(qing)(qing)(qing)銅(tong)常用(yong)于制造(zao)蝸輪(lun)、齒輪(lun)、輪(lun),以及(ji)管道工程中的閥件和管件等(deng)(deng)。



2. 鋁(Aluminum)


  鋁的(de)熔點為527℃,它具(ju)有良好的(de)導(dao)熱(re)性(xing)和(he)導(dao)電性(xing),強度和(he)硬度較低,可(ke)塑(su)性(xing)好。鋁容易氧化,在空氣中,鋁的(de)表面能形成一層極薄(bo)的(de)氧化鋁保護膜,防止繼續氧化。鋁合(he)金薄(bo)板常作為壓力管(guan)道絕熱(re)工程的(de)管(guan)子、塔、罐、換熱(re)器、閥(fa)門、法蘭以(yi)及其他(ta)平壁設(she)備保護層材料。


  純鋁的強度和(he)硬度雖(sui)然很低,但若加入其他(ta)元素可(ke)以提高(gao)。鋁合(he)金(jin)(jin)分(fen)為鑄造鋁合(he)金(jin)(jin)和(he)可(ke)壓(ya)迫變形的鋁合(he)金(jin)(jin)兩大類。管道工程中,常用L2和(he)L3牌(pai)號的鋁管輸送硝酸(suan)和(he)醋(cu)酸(suan)等,但是鋁不能抵抗堿性腐蝕。當(dang)溫度高(gao)于150℃時,鋁管不宜用于壓(ya)力(li)管道。鋁和(he)鋁合(he)金(jin)(jin)管的標(biao)準規范有(you)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(de)“附錄(lu)L-鋁合金管法蘭”。


3. 鉛(Lead)


  鉛(qian)(qian)(qian)是一種暗灰色的(de)(de)金(jin)屬,熔點為327℃,它有(you)很好的(de)(de)耐腐蝕(shi)性(xing)能,常(chang)(chang)用(yong)(yong)來制(zhi)作硫酸(suan)(suan)設備(bei)和(he)管(guan)道(dao)(dao)襯里(li)。鉛(qian)(qian)(qian)質軟,可塑(su)性(xing)好,管(guan)道(dao)(dao)工(gong)程中(zhong)(zhong)常(chang)(chang)用(yong)(yong)鉛(qian)(qian)(qian)管(guan)。在安裝鑄鐵(tie)管(guan)承插口時,常(chang)(chang)用(yong)(yong)鉛(qian)(qian)(qian)作為接口填塞材料,以牌號為Pb-6的(de)(de)鉛(qian)(qian)(qian)較適宜。硬(ying)鉛(qian)(qian)(qian)是鉛(qian)(qian)(qian)和(he)銻的(de)(de)合金(jin),它的(de)(de)抗腐蝕(shi)性(xing)略低(di)于(yu)純(chun)鉛(qian)(qian)(qian),但(dan)機(ji)械強度(du)較高,常(chang)(chang)用(yong)(yong)于(yu)制(zhi)造耐酸(suan)(suan)設備(bei)。鉛(qian)(qian)(qian)蒸氣有(you)毒,故(gu)熔化(hua)鉛(qian)(qian)(qian)時,要防止燙傷(shang)和(he)鉛(qian)(qian)(qian)中(zhong)(zhong)毒。在化(hua)工(gong)行業中(zhong)(zhong),鉛(qian)(qian)(qian)主要用(yong)(yong)在處理硫酸(suan)(suan)的(de)(de)設備(bei)上。Pb-4用(yong)(yong)于(yu)設備(bei)內(nei)襯,Pb-6用(yong)(yong)于(yu)管(guan)道(dao)(dao)接頭,硬(ying)鉛(qian)(qian)(qian)可制(zhi)造硫酸(suan)(suan)工(gong)業用(yong)(yong)的(de)(de)泵、閥(fa)門、管(guan)道(dao)(dao)等。


4. 鋅(Zinc)


  鋅(xin)(xin)呈淺灰色,熔點(dian)為419℃,它有(you)較(jiao)好(hao)的耐(nai)腐蝕性和(he)力(li)學性能。有(you)些鋼(gang)管(guan)和(he)管(guan)件為增(zeng)強(qiang)耐(nai)腐蝕性能,常(chang)在表面鍍一層鋅(xin)(xin),如室(shi)內(nei)給水工(gong)程(cheng)中常(chang)用的鍍鋅(xin)(xin)管(guan)。