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


1. 銅(Copper)


  銅(tong)又分(fen)純銅(tong)(俗稱(cheng)紫銅(tong))、黃銅(tong)和青銅(tong)等。有關(guan)銅(tong)管(guan)的標(biao)準規(gui)范包(bao)括 ASTM B42、ASTM B43、ASTM B315、ASTM B466、ASTM B467,有關(guan)銅(tong)管(guan)件(jian)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)銅(tong)(tong)(tong)呈紫紅(hong)色(se),有良好的(de)(de)導(dao)電性(xing)、導(dao)熱性(xing)和耐(nai)大(da)氣(qi)腐蝕(shi)性(xing),熔(rong)點為1083℃。在管(guan)(guan)道(dao)工程(cheng)中(zhong)常用(yong)純(chun)(chun)銅(tong)(tong)(tong)制成鋼管(guan)(guan)和法蘭(lan)墊片。因(yin)純(chun)(chun)銅(tong)(tong)(tong)硬度較低(di)(di),退火(huo)后變得更柔(rou)軟,故常用(yong)來制作高(gao)(gao)壓(ya)管(guan)(guan)道(dao)中(zhong)   的(de)(de)法蘭(lan)墊片。純(chun)(chun)銅(tong)(tong)(tong)管(guan)(guan)的(de)(de)低(di)(di)溫(wen)性(xing)能比(bi)鋼材好,故純(chun)(chun)銅(tong)(tong)(tong)管(guan)(guan)常用(yong)于空分設備管(guan)(guan)道(dao)、冷凍管(guan)(guan)道(dao)和儀表管(guan)(guan)道(dao)。純(chun)(chun)銅(tong)(tong)(tong)的(de)(de)高(gao)(gao)溫(wen)性(xing)能差,在120℃以下,允許抗拉強度為29.43MPa。溫(wen)度若再升(sheng)高(gao)(gao),其機械強度則急(ji)劇下降,當溫(wen)度上升(sheng)至250℃時,其允許抗拉強度只相當于常溫(wen)時的(de)(de)2/3,已不宜在壓(ya)力下使用(yong)。


    常用的純銅牌號為T2、T3、T4,雜質(zhi)含(han)量(liang)T2最(zui)少,T4最(zui)多。


  b. 黃銅(Brass)


   黃銅(tong)(tong)是(shi)銅(tong)(tong)和(he)鋅的(de)(de)合金,其(qi)機械(xie)強(qiang)度(du)高(gao),有(you)較好的(de)(de)耐腐蝕性(xing)和(he)澆鑄(zhu)性(xing),可用(yong)來制作(zuo)管(guan)子、管(guan)件和(he)閥(fa)門等。化(hua)工上常用(yong)的(de)(de)有(you)H80、H68、H62(“H”是(shi)黃銅(tong)(tong)代號(hao),后(hou)邊的(de)(de)數字表示合金中銅(tong)(tong)的(de)(de)平均(jun)含量(liang))。H80比H68塑(su)性(xing)好。進行強(qiang)度(du)計算時,在120℃以下,黃銅(tong)(tong)允許抗(kang)拉強(qiang)度(du)為(wei)29.43MPa。隨著溫度(du)升高(gao),其(qi)強(qiang)度(du)則急劇下降(jiang),當溫度(du)未(wei)超(chao)過(guo)225℃時,黃銅(tong)(tong)閥(fa)件可用(yong)在壓力(li)不超(chao)過(guo)1.6MPa的(de)(de)管(guan)道(dao)中。


  c. 青銅(tong)(Bronze)


    青銅(tong)(tong)是銅(tong)(tong)和錫的(de)合金,又稱錫青銅(tong)(tong)。由于(yu)錫的(de)價格(ge)較高,故制(zhi)造(zao)青銅(tong)(tong)也常用(yong)其(qi)他元素代替(ti),因(yin)而(er)又有無錫青銅(tong)(tong),如鋁青銅(tong)(tong)、鉛青銅(tong)(tong)、硅(gui)青銅(tong)(tong)等。青銅(tong)(tong)通(tong)常由澆鑄而(er)成,其(qi)強度、硬度及耐腐蝕性都比(bi)黃銅(tong)(tong)好。青銅(tong)(tong)常用(yong)于(yu)制(zhi)造(zao)蝸(gua)輪、齒輪、輪,以(yi)及管道(dao)工程中的(de)閥件(jian)和管件(jian)等。



2. 鋁(Aluminum)


  鋁的(de)熔點為527℃,它具有良(liang)好的(de)導(dao)熱性(xing)(xing)和導(dao)電(dian)性(xing)(xing),強度和硬度較低,可塑性(xing)(xing)好。鋁容易(yi)氧(yang)化,在空氣中,鋁的(de)表面能形成一層(ceng)極薄的(de)氧(yang)化鋁保(bao)護膜,防止繼(ji)續氧(yang)化。鋁合金(jin)薄板常作為壓力管道絕熱工程的(de)管子、塔、罐、換熱器、閥門、法蘭以及其他平壁(bi)設備(bei)保(bao)護層(ceng)材料。


  純(chun)鋁(lv)(lv)(lv)的(de)(de)強度和(he)硬(ying)度雖然很(hen)低(di),但(dan)若(ruo)加入其他元素(su)可以提高。鋁(lv)(lv)(lv)合金(jin)分為鑄造鋁(lv)(lv)(lv)合金(jin)和(he)可壓迫變(bian)形的(de)(de)鋁(lv)(lv)(lv)合金(jin)兩大類。管道工程中,常(chang)用L2和(he)L3牌號的(de)(de)鋁(lv)(lv)(lv)管輸送硝(xiao)酸和(he)醋(cu)酸等(deng),但(dan)是鋁(lv)(lv)(lv)不(bu)(bu)能抵抗堿(jian)性(xing)腐蝕。當溫度高于150℃時(shi),鋁(lv)(lv)(lv)管不(bu)(bu)宜用于壓力管道。鋁(lv)(lv)(lv)和(he)鋁(lv)(lv)(lv)合金(jin)管的(de)(de)標準規范有(you)ASTM B241、ASTM B26、ASTM B108、ASTM B209、ASTM B210、ASTM B211、ASTM


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


3. 鉛(Lead)


  鉛(qian)(qian)(qian)是(shi)一種暗灰色的(de)(de)金屬(shu),熔點為(wei)327℃,它(ta)有很好的(de)(de)耐腐蝕性(xing)能,常(chang)用(yong)(yong)來制作硫(liu)酸(suan)設備(bei)和管(guan)(guan)道襯里。鉛(qian)(qian)(qian)質軟,可(ke)塑性(xing)好,管(guan)(guan)道工程中(zhong)常(chang)用(yong)(yong)鉛(qian)(qian)(qian)管(guan)(guan)。在安裝鑄鐵管(guan)(guan)承插口時(shi),常(chang)用(yong)(yong)鉛(qian)(qian)(qian)作為(wei)接口填塞(sai)材料,以牌號為(wei)Pb-6的(de)(de)鉛(qian)(qian)(qian)較適宜。硬鉛(qian)(qian)(qian)是(shi)鉛(qian)(qian)(qian)和銻的(de)(de)合金,它(ta)的(de)(de)抗(kang)腐蝕性(xing)略低(di)于純(chun)鉛(qian)(qian)(qian),但機械(xie)強(qiang)度較高,常(chang)用(yong)(yong)于制造(zao)耐酸(suan)設備(bei)。鉛(qian)(qian)(qian)蒸氣有毒(du),故熔化鉛(qian)(qian)(qian)時(shi),要防止(zhi)燙(tang)傷(shang)和鉛(qian)(qian)(qian)中(zhong)毒(du)。在化工行業中(zhong),鉛(qian)(qian)(qian)主要用(yong)(yong)在處(chu)理(li)硫(liu)酸(suan)的(de)(de)設備(bei)上。Pb-4用(yong)(yong)于設備(bei)內襯,Pb-6用(yong)(yong)于管(guan)(guan)道接頭,硬鉛(qian)(qian)(qian)可(ke)制造(zao)硫(liu)酸(suan)工業用(yong)(yong)的(de)(de)泵、閥門、管(guan)(guan)道等。


4. 鋅(Zinc)


  鋅(xin)呈淺(qian)灰(hui)色(se),熔點為419℃,它有較好的(de)耐腐(fu)蝕性(xing)和力學性(xing)能(neng)。有些鋼管和管件為增(zeng)強耐腐(fu)蝕性(xing)能(neng),常在表面鍍一(yi)層鋅(xin),如室內給水工程中(zhong)常用(yong)的(de)鍍鋅(xin)管。