管道(dao)工程(cheng)中常(chang)用的有色(se)金屬(Non-ferrous Metal)有銅(tong)、鋁、鉛和鋅(xin)等。


1. 銅(tong)(Copper)


  銅又分純銅(俗稱紫銅)、黃(huang)銅和青銅等。有關銅管(guan)的標(biao)準規(gui)范包括 ASTM B42、ASTM B43、ASTM B315、ASTM B466、ASTM B467,有關銅管(guan)件的標(biao)準規(gui)范有ASMEB16.24、ASME B16.22、ASME B16.15、ASME B16.18等。


 a. 純銅(Copper)


    純(chun)(chun)(chun)(chun)銅(tong)(tong)呈紫紅色,有(you)良(liang)好(hao)的(de)導電(dian)性、導熱(re)性和(he)耐大氣腐蝕性,熔(rong)點(dian)為(wei)1083℃。在(zai)管道(dao)工程中常(chang)用純(chun)(chun)(chun)(chun)銅(tong)(tong)制(zhi)成鋼(gang)管和(he)法蘭墊片。因純(chun)(chun)(chun)(chun)銅(tong)(tong)硬(ying)度(du)較(jiao)低,退(tui)火后變(bian)得更柔軟,故(gu)常(chang)用來制(zhi)作高壓管道(dao)中   的(de)法蘭墊片。純(chun)(chun)(chun)(chun)銅(tong)(tong)管的(de)低溫(wen)性能比鋼(gang)材(cai)好(hao),故(gu)純(chun)(chun)(chun)(chun)銅(tong)(tong)管常(chang)用于(yu)空分(fen)設(she)備管道(dao)、冷凍管道(dao)和(he)儀表管道(dao)。純(chun)(chun)(chun)(chun)銅(tong)(tong)的(de)高溫(wen)性能差(cha),在(zai)120℃以(yi)下(xia),允許抗(kang)拉強度(du)為(wei)29.43MPa。溫(wen)度(du)若(ruo)再(zai)升高,其(qi)機械(xie)強度(du)則急劇下(xia)降(jiang),當溫(wen)度(du)上升至250℃時(shi),其(qi)允許抗(kang)拉強度(du)只相(xiang)當于(yu)常(chang)溫(wen)時(shi)的(de)2/3,已不宜在(zai)壓力下(xia)使用。


    常用(yong)的純銅牌號(hao)為T2、T3、T4,雜質含(han)量(liang)T2最少,T4最多。


  b. 黃銅(tong)(Brass)


   黃銅(tong)是(shi)銅(tong)和鋅的(de)合(he)金,其機械強(qiang)度高,有(you)較好(hao)的(de)耐(nai)腐蝕性(xing)(xing)和澆(jiao)鑄(zhu)性(xing)(xing),可用來制作(zuo)管(guan)子、管(guan)件和閥門等(deng)。化工上常用的(de)有(you)H80、H68、H62(“H”是(shi)黃銅(tong)代號,后邊的(de)數(shu)字表示合(he)金中(zhong)銅(tong)的(de)平均含量)。H80比H68塑性(xing)(xing)好(hao)。進行強(qiang)度計算時(shi),在120℃以(yi)下(xia),黃銅(tong)允(yun)許(xu)抗拉強(qiang)度為29.43MPa。隨著溫(wen)度升高,其強(qiang)度則急劇下(xia)降,當溫(wen)度未超過225℃時(shi),黃銅(tong)閥件可用在壓力不超過1.6MPa的(de)管(guan)道中(zhong)。


  c. 青銅(Bronze)


    青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)是銅(tong)(tong)(tong)(tong)(tong)(tong)和錫的合金,又稱(cheng)錫青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)。由于錫的價格較高,故制(zhi)造(zao)青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)也常(chang)用(yong)其他元素代替,因而(er)又有無(wu)錫青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong),如鋁青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)、鉛青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)、硅青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)等。青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)通常(chang)由澆(jiao)鑄而(er)成(cheng),其強度、硬(ying)度及(ji)耐腐蝕性都(dou)比(bi)黃銅(tong)(tong)(tong)(tong)(tong)(tong)好。青(qing)(qing)(qing)銅(tong)(tong)(tong)(tong)(tong)(tong)常(chang)用(yong)于制(zhi)造(zao)蝸輪、齒輪、輪,以及(ji)管(guan)道工程中的閥(fa)件(jian)和管(guan)件(jian)等。



2. 鋁(Aluminum)


  鋁的(de)(de)熔(rong)點為527℃,它具有良好(hao)的(de)(de)導熱性和導電(dian)性,強(qiang)度和硬度較低,可塑性好(hao)。鋁容(rong)易氧(yang)化,在空氣中,鋁的(de)(de)表面能形成(cheng)一層極薄(bo)(bo)的(de)(de)氧(yang)化鋁保護(hu)膜,防(fang)止繼續氧(yang)化。鋁合金薄(bo)(bo)板常作(zuo)為壓力管道絕熱工程的(de)(de)管子、塔、罐、換熱器、閥(fa)門、法(fa)蘭以及其他(ta)平壁(bi)設備保護(hu)層材料。


  純鋁(lv)的(de)強度(du)和(he)硬度(du)雖(sui)然很低,但若(ruo)加(jia)入(ru)其他元素可(ke)以提高(gao)。鋁(lv)合(he)(he)金(jin)分(fen)為(wei)鑄造(zao)鋁(lv)合(he)(he)金(jin)和(he)可(ke)壓迫變形(xing)的(de)鋁(lv)合(he)(he)金(jin)兩(liang)大類。管(guan)道(dao)工程(cheng)中,常用L2和(he)L3牌(pai)號的(de)鋁(lv)管(guan)輸(shu)送硝酸和(he)醋酸等,但是鋁(lv)不能抵抗堿性腐蝕。當(dang)溫度(du)高(gao)于150℃時,鋁(lv)管(guan)不宜(yi)用于壓力管(guan)道(dao)。鋁(lv)和(he)鋁(lv)合(he)(he)金(jin)管(guan)的(de)標準規范有ASTM B241、ASTM B26、ASTM B108、ASTM B209、ASTM B210、ASTM B211、ASTM


  B221、ASTMI B234、ASTM B247 以及 ASME B31.3的“附錄L-鋁合金管法蘭”。


3. 鉛(Lead)


  鉛(qian)(qian)(qian)是(shi)一種(zhong)暗灰(hui)色的(de)金屬,熔(rong)點為(wei)(wei)327℃,它(ta)有很好的(de)耐(nai)腐(fu)(fu)蝕(shi)性(xing)能(neng),常(chang)(chang)用(yong)(yong)來制作(zuo)硫(liu)酸(suan)設(she)(she)備(bei)(bei)和管(guan)(guan)道襯里。鉛(qian)(qian)(qian)質(zhi)軟,可塑(su)性(xing)好,管(guan)(guan)道工程中(zhong)常(chang)(chang)用(yong)(yong)鉛(qian)(qian)(qian)管(guan)(guan)。在安裝鑄鐵管(guan)(guan)承插(cha)口(kou)時,常(chang)(chang)用(yong)(yong)鉛(qian)(qian)(qian)作(zuo)為(wei)(wei)接口(kou)填塞材(cai)料,以牌(pai)號為(wei)(wei)Pb-6的(de)鉛(qian)(qian)(qian)較適(shi)宜(yi)。硬(ying)鉛(qian)(qian)(qian)是(shi)鉛(qian)(qian)(qian)和銻的(de)合金,它(ta)的(de)抗腐(fu)(fu)蝕(shi)性(xing)略(lve)低于純鉛(qian)(qian)(qian),但(dan)機械強度較高,常(chang)(chang)用(yong)(yong)于制造耐(nai)酸(suan)設(she)(she)備(bei)(bei)。鉛(qian)(qian)(qian)蒸氣(qi)有毒(du),故熔(rong)化(hua)鉛(qian)(qian)(qian)時,要防止燙(tang)傷和鉛(qian)(qian)(qian)中(zhong)毒(du)。在化(hua)工行業(ye)中(zhong),鉛(qian)(qian)(qian)主要用(yong)(yong)在處理硫(liu)酸(suan)的(de)設(she)(she)備(bei)(bei)上(shang)。Pb-4用(yong)(yong)于設(she)(she)備(bei)(bei)內襯,Pb-6用(yong)(yong)于管(guan)(guan)道接頭,硬(ying)鉛(qian)(qian)(qian)可制造硫(liu)酸(suan)工業(ye)用(yong)(yong)的(de)泵、閥(fa)門、管(guan)(guan)道等。


4. 鋅(Zinc)


  鋅(xin)呈淺灰色(se),熔(rong)點為419℃,它有(you)較好的(de)(de)耐腐(fu)蝕性和力學性能。有(you)些鋼(gang)管和管件為增強耐腐(fu)蝕性能,常在表面鍍(du)一層鋅(xin),如(ru)室(shi)內給水工程中常用的(de)(de)鍍(du)鋅(xin)管。