管道(dao)工程中常用的有色(se)金屬(Non-ferrous Metal)有銅(tong)、鋁(lv)、鉛(qian)和鋅等(deng)。


1. 銅(Copper)


  銅(tong)(tong)(tong)又分(fen)純銅(tong)(tong)(tong)(俗(su)稱紫銅(tong)(tong)(tong))、黃銅(tong)(tong)(tong)和(he)青銅(tong)(tong)(tong)等(deng)。有(you)(you)關銅(tong)(tong)(tong)管(guan)的(de)(de)標準規范包括(kuo) ASTM B42、ASTM B43、ASTM B315、ASTM B466、ASTM B467,有(you)(you)關銅(tong)(tong)(tong)管(guan)件的(de)(de)標準規范有(you)(you)ASMEB16.24、ASME B16.22、ASME B16.15、ASME B16.18等(deng)。


 a. 純銅(Copper)


    純銅(tong)(tong)呈紫紅(hong)色(se),有良好(hao)的(de)導(dao)電性(xing)、導(dao)熱性(xing)和耐(nai)大氣腐(fu)蝕性(xing),熔(rong)點為1083℃。在管(guan)(guan)道(dao)工程中(zhong)常用純銅(tong)(tong)制(zhi)成鋼管(guan)(guan)和法(fa)蘭墊片(pian)。因純銅(tong)(tong)硬度(du)(du)(du)(du)較低(di),退(tui)火后變得更柔軟,故常用來制(zhi)作(zuo)高(gao)壓管(guan)(guan)道(dao)中(zhong)   的(de)法(fa)蘭墊片(pian)。純銅(tong)(tong)管(guan)(guan)的(de)低(di)溫(wen)性(xing)能比鋼材好(hao),故純銅(tong)(tong)管(guan)(guan)常用于空分設備管(guan)(guan)道(dao)、冷(leng)凍(dong)管(guan)(guan)道(dao)和儀表管(guan)(guan)道(dao)。純銅(tong)(tong)的(de)高(gao)溫(wen)性(xing)能差(cha),在120℃以下,允(yun)許抗(kang)拉(la)強度(du)(du)(du)(du)為29.43MPa。溫(wen)度(du)(du)(du)(du)若(ruo)再升高(gao),其機械強度(du)(du)(du)(du)則急劇下降,當溫(wen)度(du)(du)(du)(du)上升至250℃時,其允(yun)許抗(kang)拉(la)強度(du)(du)(du)(du)只相當于常溫(wen)時的(de)2/3,已不宜在壓力(li)下使用。


    常用(yong)的(de)純(chun)銅牌號為T2、T3、T4,雜質含量T2最少,T4最多。


  b. 黃銅(Brass)


   黃(huang)(huang)銅(tong)是銅(tong)和鋅的(de)合(he)金,其機械強度(du)(du)高,有較好(hao)的(de)耐腐蝕性(xing)(xing)和澆鑄性(xing)(xing),可用(yong)(yong)來(lai)制作管(guan)子、管(guan)件(jian)和閥門等。化工上(shang)常(chang)用(yong)(yong)的(de)有H80、H68、H62(“H”是黃(huang)(huang)銅(tong)代(dai)號,后(hou)邊的(de)數字表示合(he)金中(zhong)銅(tong)的(de)平(ping)均含量)。H80比(bi)H68塑性(xing)(xing)好(hao)。進行(xing)強度(du)(du)計算(suan)時(shi),在120℃以(yi)下,黃(huang)(huang)銅(tong)允許抗拉強度(du)(du)為29.43MPa。隨著溫(wen)度(du)(du)升高,其強度(du)(du)則急(ji)劇下降,當(dang)溫(wen)度(du)(du)未(wei)超過225℃時(shi),黃(huang)(huang)銅(tong)閥件(jian)可用(yong)(yong)在壓力不超過1.6MPa的(de)管(guan)道(dao)中(zhong)。


  c. 青銅(tong)(Bronze)


    青(qing)(qing)銅(tong)(tong)(tong)是(shi)銅(tong)(tong)(tong)和錫(xi)(xi)的合金(jin),又稱錫(xi)(xi)青(qing)(qing)銅(tong)(tong)(tong)。由于錫(xi)(xi)的價格較高,故制造青(qing)(qing)銅(tong)(tong)(tong)也常(chang)(chang)用(yong)其他元素代替,因而(er)又有無錫(xi)(xi)青(qing)(qing)銅(tong)(tong)(tong),如鋁青(qing)(qing)銅(tong)(tong)(tong)、鉛青(qing)(qing)銅(tong)(tong)(tong)、硅青(qing)(qing)銅(tong)(tong)(tong)等。青(qing)(qing)銅(tong)(tong)(tong)通常(chang)(chang)由澆鑄而(er)成,其強(qiang)度、硬度及(ji)耐腐蝕性都比黃(huang)銅(tong)(tong)(tong)好。青(qing)(qing)銅(tong)(tong)(tong)常(chang)(chang)用(yong)于制造蝸輪(lun)、齒輪(lun)、輪(lun),以及(ji)管(guan)道工程中的閥件和管(guan)件等。



2. 鋁(Aluminum)


  鋁的(de)熔點為(wei)527℃,它具(ju)有良好(hao)的(de)導(dao)熱(re)性和導(dao)電性,強(qiang)度和硬(ying)度較(jiao)低(di),可塑性好(hao)。鋁容易氧化,在空氣(qi)中,鋁的(de)表面能形成一層極薄的(de)氧化鋁保護膜(mo),防止繼續氧化。鋁合金薄板常作為(wei)壓力管道(dao)絕熱(re)工程的(de)管子、塔、罐、換熱(re)器、閥門、法(fa)蘭(lan)以及其(qi)他(ta)平壁(bi)設備保護層材料。


  純鋁(lv)的(de)強度(du)和(he)(he)硬度(du)雖(sui)然(ran)很低,但(dan)若加入其他元素可以提高。鋁(lv)合金分為鑄造(zao)鋁(lv)合金和(he)(he)可壓(ya)迫變(bian)形的(de)鋁(lv)合金兩大類。管道工程(cheng)中,常用L2和(he)(he)L3牌號的(de)鋁(lv)管輸(shu)送硝(xiao)酸(suan)和(he)(he)醋酸(suan)等,但(dan)是鋁(lv)不能抵抗堿性腐蝕。當溫度(du)高于150℃時,鋁(lv)管不宜用于壓(ya)力(li)管道。鋁(lv)和(he)(he)鋁(lv)合金管的(de)標準(zhun)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(lu)L-鋁合金(jin)管(guan)法蘭”。


3. 鉛(Lead)


  鉛是(shi)一種(zhong)暗灰(hui)色的(de)金屬,熔點(dian)為(wei)327℃,它(ta)有很好(hao)的(de)耐腐蝕性(xing)能,常用(yong)來(lai)制作硫酸設(she)(she)備和管(guan)(guan)(guan)道襯里。鉛質(zhi)軟(ruan),可(ke)塑性(xing)好(hao),管(guan)(guan)(guan)道工(gong)(gong)程(cheng)中常用(yong)鉛管(guan)(guan)(guan)。在安裝鑄(zhu)鐵管(guan)(guan)(guan)承插口時,常用(yong)鉛作為(wei)接(jie)口填塞材料,以(yi)牌號為(wei)Pb-6的(de)鉛較適(shi)宜(yi)。硬鉛是(shi)鉛和銻的(de)合(he)金,它(ta)的(de)抗(kang)腐蝕性(xing)略低(di)于純(chun)鉛,但機械強度較高(gao),常用(yong)于制造耐酸設(she)(she)備。鉛蒸氣有毒(du),故熔化(hua)鉛時,要防止燙(tang)傷和鉛中毒(du)。在化(hua)工(gong)(gong)行業中,鉛主要用(yong)在處理(li)硫酸的(de)設(she)(she)備上。Pb-4用(yong)于設(she)(she)備內(nei)襯,Pb-6用(yong)于管(guan)(guan)(guan)道接(jie)頭,硬鉛可(ke)制造硫酸工(gong)(gong)業用(yong)的(de)泵、閥門、管(guan)(guan)(guan)道等(deng)。


4. 鋅(Zinc)


  鋅呈淺(qian)灰色,熔點為(wei)419℃,它有較好的耐腐(fu)蝕性(xing)和力(li)學性(xing)能。有些(xie)鋼管和管件為(wei)增強耐腐(fu)蝕性(xing)能,常在表面鍍一層鋅,如(ru)室內給水(shui)工程(cheng)中常用的鍍鋅管。