金屬管在管路中應用極為廣泛,現將常用金屬管介紹如下。
1. 鋼管(guan)
鋼(gang)管(guan)(guan)分(fen)為有縫鋼(gang)管(guan)(guan)和無(wu)縫鋼(gang)管(guan)(guan)兩大類。
①. 有縫鋼管(guan)又稱為焊接(jie)鋼管(guan)
可(ke)分為(wei)低壓流體輸(shu)送鋼(gang)管(guan)和(he)(he)電焊鋼(gang)管(guan)兩類。低壓流體輸(shu)送鋼(gang)管(guan)是由扁(bian)鋼(gang)管(guan)坯卷成管(guan)形并沿(yan)縫焊接而成的(de)(de)(de),因為(wei)它常用來輸(shu)送水和(he)(he)煤(mei)氣,故俗稱為(wei)水煤(mei)氣管(guan)。水煤(mei)氣管(guan)可(ke)分為(wei)鍍鋅(xin)的(de)(de)(de)和(he)(he)不鍍鋅(xin)的(de)(de)(de);普通的(de)(de)(de)和(he)(he)加厚的(de)(de)(de);帶螺紋(wen)的(de)(de)(de)和(he)(he)不帶螺紋(wen)的(de)(de)(de)等(deng)類型。
水(shui)煤氣鋼(gang)管(guan)廣泛(fan)應用在小直徑的低壓(ya)(ya)管(guan)路上,如給水(shui)、煤氣、暖氣、壓(ya)(ya)縮(suo)空氣、蒸汽、凝結(jie)水(shui)、廢氣、真空及某些物(wu)料管(guan)路。普(pu)通鋼(gang)管(guan)正(zheng)(zheng)常(chang)工(gong)作(zuo)壓(ya)(ya)力(li)不(bu)大于0.6MPa(表(biao)壓(ya)(ya));加(jia)厚(hou)鋼(gang)管(guan)正(zheng)(zheng)常(chang)工(gong)作(zuo)壓(ya)(ya)力(li)不(bu)大于1MPa(表(biao)壓(ya)(ya))。正(zheng)(zheng)常(chang)工(gong)作(zuo)溫(wen)度不(bu)宜超過175℃。最大水(shui)壓(ya)(ya)試(shi)驗壓(ya)(ya)力(li):普(pu)通鋼(gang)管(guan)為2MPa,加(jia)厚(hou)鋼(gang)管(guan)為3MPa。
電焊鋼管是(shi)由軟鋼板條卷成管形后焊接而成的鋼管,分直焊縫和螺(luo)旋(xuan)焊縫兩種類型。
直(zhi)(zhi)焊(han)縫的電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan),又(you)可(ke)分為(wei)(wei)(wei)小直(zhi)(zhi)徑(jing)(jing)(jing)電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)和(he)大(da)直(zhi)(zhi)徑(jing)(jing)(jing)電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)兩類。小直(zhi)(zhi)徑(jing)(jing)(jing)的電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)外(wai)徑(jing)(jing)(jing)為(wei)(wei)(wei)5~152mm,壁厚(hou)為(wei)(wei)(wei)0.5~5.5mm.大(da)直(zhi)(zhi)徑(jing)(jing)(jing)的電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)又(you)稱鋼(gang)(gang)(gang)(gang)(gang)板卷管(guan)(guan)(guan)(guan),其(qi)外(wai)徑(jing)(jing)(jing)為(wei)(wei)(wei)530~2020mm,壁厚(hou)為(wei)(wei)(wei)4~16mm.螺(luo)旋縫電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)外(wai)徑(jing)(jing)(jing)為(wei)(wei)(wei)219~720mm,壁厚(hou)為(wei)(wei)(wei)6~7mm.電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)可(ke)用于壓(ya)力(li)不(bu)高或無嚴格(ge)要(yao)求的管(guan)(guan)(guan)(guan)路(lu)上(shang)。電(dian)(dian)(dian)焊(han)鋼(gang)(gang)(gang)(gang)(gang)管(guan)(guan)(guan)(guan)的正常工作溫(wen)度不(bu)宜超過200℃。
②. 無縫鋼管
是由圓(yuan)鋼(gang)坯加熱(re)(re)后,經穿(chuan)管(guan)機穿(chuan)孔軋(ya)制(熱(re)(re)軋(ya))而(er)成的或者再經過冷(leng)拔(ba)而(er)成為外(wai)徑較(jiao)小的管(guan)子,因為它沒有接縫,所以稱為無縫鋼(gang)管(guan)。
無縫鋼管按照制造方(fang)法的(de)不同,又(you)分(fen)為(wei)(wei)(wei)熱軋無縫鋼管和冷拔無縫鋼管兩類。熱軋無縫鋼管的(de)規(gui)格(ge):外徑為(wei)(wei)(wei)32~630mm,壁(bi)厚為(wei)(wei)(wei)2.5~75mm,管長(chang)為(wei)(wei)(wei)4~12.5m;冷拔無縫鋼管的(de)規(gui)格(ge):外徑為(wei)(wei)(wei)2~150mm,壁(bi)厚為(wei)(wei)(wei)0.25~14mm,管長(chang)為(wei)(wei)(wei)1.5~9m。
無(wu)縫(feng)(feng)鋼管(guan)(guan)強度高,可(ke)用(yong)(yong)在重要管(guan)(guan)路上,如(ru)高壓(ya)(ya)蒸汽和(he)過熱蒸汽的(de)管(guan)(guan)路、高壓(ya)(ya)水(shui)和(he)過熱水(shui)管(guan)(guan)路、高壓(ya)(ya)氣體(ti)和(he)液體(ti)管(guan)(guan)路以及輸(shu)送燃燒性(xing)、爆炸(zha)性(xing)和(he)有毒害性(xing)的(de)物料管(guan)(guan)路等。各種熱交(jiao)換器的(de)管(guan)(guan)子大都采用(yong)(yong)無(wu)縫(feng)(feng)鋼管(guan)(guan)。中、低壓(ya)(ya)管(guan)(guan)路無(wu)縫(feng)(feng)鋼管(guan)(guan)的(de)最(zui)高工作溫(wen)(wen)度:碳(tan)鋼為(wei)(wei)250℃;優(you)質(zhi)碳(tan)鋼(如(ru)10鋼)為(wei)(wei)450℃.高壓(ya)(ya)管(guan)(guan)路均用(yong)(yong)優(you)質(zhi)碳(tan)鋼(20鋼)制成的(de)無(wu)縫(feng)(feng)鋼管(guan)(guan),最(zui)高工作溫(wen)(wen)度為(wei)(wei)200℃。
輸送強腐蝕性或高(gao)(gao)溫的介(jie)質時,采用不(bu)銹鋼(gang)、耐酸鋼(gang)或耐熱(re)(re)(re)鋼(gang)制的無縫(feng)鋼(gang)管。這種無縫(feng)鋼(gang)管也可用熱(re)(re)(re)軋而成(cheng)或再冷拔成(cheng)尺寸較小的管子。熱(re)(re)(re)軋管的規(gui)格(ge):外徑為(wei)6~89mm,壁厚為(wei)1~7mm,長(chang)度(du)為(wei)1.5~7m.耐熱(re)(re)(re)鋼(gang)管最(zui)高(gao)(gao)工作溫度(du)為(wei)850℃。
輸送高壓水時,可以采用厚(hou)壁(bi)無縫鋼管,它的外(wai)徑為12~219mm,壁(bi)厚(hou)為3.5~40mm,長度為3~4m,最高工作溫度為375℃。
2. 鑄鐵管
鑄鐵管分為普通鑄鐵管和(he)硅鐵管兩類。
①. 普通鑄鐵管(guan)
一(yi)般用灰口(kou)鐵鑄(zhu)造,耐蝕(shi)性好,但質脆,不抗沖擊。常用于埋地給水管道、煤氣管道和(he)室內排水管道。給水鑄(zhu)鐵管有低壓(p=0.45MPa)、常壓(p=0.75MPa)和(he)高(gao)壓(p=1MPa)三種,直徑50~1500mm,壁厚7.5~30mm,管長3m、4m、6m.管端形狀分承(cheng)插式和(he)法蘭(lan)式兩種,其(qi)中以承(cheng)插式最常用。
排水鑄(zhu)鐵(tie)管只有承(cheng)插式一(yi)種。直(zhi)徑50~200mm,壁厚4~7mm,長(chang)度有0.5m、1m、1.5m、2m等多種,但一(yi)般為2m。排水鑄(zhu)鐵(tie)管比(bi)給水鑄(zhu)鐵(tie)管壁薄(bo),承(cheng)口也淺,使用時可根據(ju)外形(xing)加以判(pan)別。
②. 硅鐵管(guan)
可分(fen)為(wei)高(gao)(gao)硅(gui)鐵(tie)管(guan)和(he)抗氯(lv)硅(gui)鐵(tie)管(guan)兩種。高(gao)(gao)硅(gui)鐵(tie)管(guan)能(neng)抵(di)抗多種強(qiang)酸(suan)的(de)腐(fu)蝕(shi),而含鉬的(de)抗氯(lv)硅(gui)鑄鐵(tie)可抵(di)抗各種濃度(du)(du)和(he)溫度(du)(du)的(de)鹽酸(suan),因此(ci)是(shi)很好(hao)的(de)耐腐(fu)蝕(shi)管(guan)材。高(gao)(gao)硅(gui)合(he)金鑄件(jian)硬度(du)(du)大,只(zhi)能(neng)用金剛砂輪(lun)修磨或用硬質合(he)金刀具(ju)來加工。高(gao)(gao)硅(gui)合(he)金制(zhi)件(jian)受(shou)到輕微敲擊、局部受(shou)熱或急劇冷卻(que)時,皆易破裂,但是(shi)由于其(qi)耐腐(fu)蝕(shi)性好(hao),所(suo)以廣泛應用于化工管(guan)路中(zhong)。
高硅(gui)鑄鐵管(guan)(guan)和(he)抗氯硅(gui)鑄鐵管(guan)(guan)的內(nei)徑(jing)為(wei)32~300mm,壁厚為(wei)10~16mm,長度為(wei)150~2000mm.用(yong)于輸送公稱壓力(li)低(di)于0.25MPa的腐蝕性介質。硅(gui)鐵管(guan)(guan)的耐熱性能好,可達(da)900℃.硅(gui)鐵管(guan)(guan)的兩端有供連接用(yong)的凸肩,利用(yong)對開(kai)式的松套法蘭連接。
3. 紫銅(tong)管和黃銅(tong)管
紫銅(tong)管(guan)(guan)和黃銅(tong)管(guan)(guan)都是拔(ba)制(zhi)(zhi)或擠制(zhi)(zhi)而成的(de)無縫(feng)管(guan)(guan),主要用(yong)于(yu)制(zhi)(zhi)造換熱設(she)備(bei)、制(zhi)(zhi)氧設(she)備(bei)中(zhong)的(de)低溫管(guan)(guan)路(lu)以及(ji)機(ji)械(xie)設(she)備(bei)中(zhong)的(de)油管(guan)(guan)和控制(zhi)(zhi)系(xi)統的(de)管(guan)(guan)路(lu)。
拔制紫(zi)(zi)銅(tong)(tong)管(guan)(guan)(guan)外(wai)徑(jing)(jing)為(wei)(wei)3~360mm,壁厚為(wei)(wei)0.5~10mm;壓制紫(zi)(zi)銅(tong)(tong)管(guan)(guan)(guan)外(wai)徑(jing)(jing)為(wei)(wei)30~280mm,壁厚為(wei)(wei)5~30mm.管(guan)(guan)(guan)長均(jun)為(wei)(wei)1~6m,隨管(guan)(guan)(guan)子外(wai)徑(jing)(jing)與制造方法而異(yi)。拔制的(de)盤狀(zhuang)紫(zi)(zi)銅(tong)(tong)管(guan)(guan)(guan)直徑(jing)(jing)較小,每(mei)盤管(guan)(guan)(guan)子長度從十幾米至數十米,黃(huang)銅(tong)(tong)管(guan)(guan)(guan)外(wai)徑(jing)(jing)為(wei)(wei)3~195mm.當工作溫度高于(yu)250℃時,不宜(yi)在壓力下使用紫(zi)(zi)銅(tong)(tong)管(guan)(guan)(guan)和(he)黃(huang)銅(tong)(tong)管(guan)(guan)(guan)。紫(zi)(zi)銅(tong)(tong)管(guan)(guan)(guan)和(he)黃(huang)銅(tong)(tong)管(guan)(guan)(guan)可以采用焊接(jie)(jie)連(lian)接(jie)(jie)、法蘭(lan)連(lian)接(jie)(jie)和(he)螺(luo)紋連(lian)接(jie)(jie)。
4. 鋁管(guan)
鋁(lv)管(guan)是拔制(zhi)而成的(de)無縫鋁(lv)管(guan),它主(zhu)要(yao)用來輸送濃硝酸(suan)(suan)、醋酸(suan)(suan)、甲(jia)酸(suan)(suan)及其他介質,但不能(neng)抗堿(jian)液(ye)。鋁(lv)管(guan)外徑為(wei)6~120mm,壁厚(hou)為(wei)1~10mm,管(guan)長可達6m.當工作溫(wen)度高于160℃時,不宜在(zai)壓力下使用鋁(lv)管(guan)。鋁(lv)管(guan)的(de)連(lian)(lian)接采用焊接連(lian)(lian)接和法蘭連(lian)(lian)接。
5. 鉛管
鉛(qian)(qian)(qian)管(guan)(guan)(guan)對硫酸(suan)具有良好的耐蝕性,因此廣泛應用于(yu)硫酸(suan)工業(ye)中,但由(you)于(yu)鉛(qian)(qian)(qian)管(guan)(guan)(guan)有強度低、密度大、抗熱性能差(cha)等缺點,故近來已逐漸(jian)被(bei)各(ge)種耐酸(suan)合(he)金(jin)管(guan)(guan)(guan)與塑料管(guan)(guan)(guan)所(suo)(suo)代替。鉛(qian)(qian)(qian)管(guan)(guan)(guan)的內(nei)(nei)徑(jing)為8~150mm,壁厚為2~10mm.內(nei)(nei)徑(jing)小于(yu)55mm的鉛(qian)(qian)(qian)管(guan)(guan)(guan)多(duo)制成(cheng)盤(pan)管(guan)(guan)(guan),內(nei)(nei)徑(jing)大于(yu)60mm時(shi)才做成(cheng)直(zhi)管(guan)(guan)(guan),每根(gen)長2~2.5m.由(you)于(yu)鉛(qian)(qian)(qian)易(yi)(yi)于(yu)輾(zhan)壓(ya)、鍛制和焊(han)接,所(suo)(suo)以(yi)大直(zhi)徑(jing)的鉛(qian)(qian)(qian)管(guan)(guan)(guan)很容(rong)易(yi)(yi)用鉛(qian)(qian)(qian)板焊(han)制而(er)成(cheng);也(ye)可以(yi)在鉛(qian)(qian)(qian)中加入(ru)8%~10%的銻,而(er)形成(cheng)鉛(qian)(qian)(qian)銻合(he)金(jin),此合(he)金(jin)通常(chang)稱為硬鉛(qian)(qian)(qian),它可用于(yu)鑄造鉛(qian)(qian)(qian)管(guan)(guan)(guan)。
鉛(qian)管的連接(jie)可采用焊接(jie)連接(jie)和法蘭連接(jie)。工(gong)作溫度(du)高(gao)于140℃時(shi),就不宜在壓力下使(shi)用鉛(qian)管。

