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
鋼(gang)(gang)管(guan)分為有縫(feng)鋼(gang)(gang)管(guan)和無縫(feng)鋼(gang)(gang)管(guan)兩大(da)類。
①. 有(you)縫(feng)鋼(gang)管又(you)稱為焊接鋼(gang)管
可(ke)分為低(di)壓流體輸送鋼(gang)管(guan)(guan)(guan)和電焊鋼(gang)管(guan)(guan)(guan)兩(liang)類。低(di)壓流體輸送鋼(gang)管(guan)(guan)(guan)是由扁(bian)鋼(gang)管(guan)(guan)(guan)坯卷成管(guan)(guan)(guan)形并沿(yan)縫焊接而成的(de)(de)(de),因(yin)為它常用(yong)來輸送水(shui)(shui)和煤氣,故(gu)俗稱為水(shui)(shui)煤氣管(guan)(guan)(guan)。水(shui)(shui)煤氣管(guan)(guan)(guan)可(ke)分為鍍(du)(du)鋅的(de)(de)(de)和不鍍(du)(du)鋅的(de)(de)(de);普通的(de)(de)(de)和加厚(hou)的(de)(de)(de);帶螺紋(wen)(wen)的(de)(de)(de)和不帶螺紋(wen)(wen)的(de)(de)(de)等類型(xing)。
水(shui)煤氣(qi)鋼(gang)管廣(guang)泛應用在小直徑的(de)低壓(ya)管路(lu)上,如(ru)給水(shui)、煤氣(qi)、暖氣(qi)、壓(ya)縮空氣(qi)、蒸汽、凝結水(shui)、廢氣(qi)、真空及某些物料管路(lu)。普通鋼(gang)管正(zheng)常工作壓(ya)力不(bu)大于0.6MPa(表(biao)壓(ya));加厚(hou)鋼(gang)管正(zheng)常工作壓(ya)力不(bu)大于1MPa(表(biao)壓(ya))。正(zheng)常工作溫度不(bu)宜超(chao)過175℃。最大水(shui)壓(ya)試(shi)驗壓(ya)力:普通鋼(gang)管為2MPa,加厚(hou)鋼(gang)管為3MPa。
電(dian)焊(han)鋼管(guan)是由軟鋼板條(tiao)卷成管(guan)形后焊(han)接(jie)而(er)成的鋼管(guan),分直焊(han)縫和螺(luo)旋焊(han)縫兩種類型。
直焊(han)(han)縫(feng)的(de)(de)(de)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan),又可(ke)分為(wei)(wei)小直徑(jing)(jing)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)和(he)大直徑(jing)(jing)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)兩類。小直徑(jing)(jing)的(de)(de)(de)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)外徑(jing)(jing)為(wei)(wei)5~152mm,壁厚為(wei)(wei)0.5~5.5mm.大直徑(jing)(jing)的(de)(de)(de)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)又稱鋼(gang)板卷管(guan)(guan),其外徑(jing)(jing)為(wei)(wei)530~2020mm,壁厚為(wei)(wei)4~16mm.螺旋縫(feng)電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)外徑(jing)(jing)為(wei)(wei)219~720mm,壁厚為(wei)(wei)6~7mm.電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)可(ke)用于壓力(li)不高或(huo)無嚴(yan)格要(yao)求的(de)(de)(de)管(guan)(guan)路上(shang)。電(dian)(dian)(dian)焊(han)(han)鋼(gang)管(guan)(guan)的(de)(de)(de)正常工(gong)作(zuo)溫度(du)不宜超過(guo)200℃。
②. 無(wu)縫鋼管(guan)
是由圓(yuan)鋼坯(pi)加熱(re)后(hou),經穿(chuan)管機穿(chuan)孔軋(ya)制(熱(re)軋(ya))而成(cheng)的或者(zhe)再經過冷拔而成(cheng)為(wei)外徑較小的管子,因為(wei)它沒有接(jie)縫(feng),所(suo)以稱為(wei)無縫(feng)鋼管。
無(wu)縫鋼(gang)管(guan)(guan)按照制造方(fang)法的不(bu)同,又(you)分為(wei)(wei)(wei)熱軋無(wu)縫鋼(gang)管(guan)(guan)和冷(leng)拔(ba)無(wu)縫鋼(gang)管(guan)(guan)兩類(lei)。熱軋無(wu)縫鋼(gang)管(guan)(guan)的規(gui)格:外徑(jing)(jing)為(wei)(wei)(wei)32~630mm,壁厚為(wei)(wei)(wei)2.5~75mm,管(guan)(guan)長(chang)為(wei)(wei)(wei)4~12.5m;冷(leng)拔(ba)無(wu)縫鋼(gang)管(guan)(guan)的規(gui)格:外徑(jing)(jing)為(wei)(wei)(wei)2~150mm,壁厚為(wei)(wei)(wei)0.25~14mm,管(guan)(guan)長(chang)為(wei)(wei)(wei)1.5~9m。
無(wu)縫鋼(gang)(gang)管(guan)(guan)(guan)(guan)強度(du)高(gao),可用(yong)(yong)在(zai)重要管(guan)(guan)(guan)(guan)路(lu)上,如(ru)高(gao)壓(ya)蒸(zheng)汽(qi)和(he)(he)(he)過熱(re)蒸(zheng)汽(qi)的管(guan)(guan)(guan)(guan)路(lu)、高(gao)壓(ya)水(shui)和(he)(he)(he)過熱(re)水(shui)管(guan)(guan)(guan)(guan)路(lu)、高(gao)壓(ya)氣體和(he)(he)(he)液體管(guan)(guan)(guan)(guan)路(lu)以及(ji)輸送燃燒性(xing)、爆炸(zha)性(xing)和(he)(he)(he)有毒害性(xing)的物料管(guan)(guan)(guan)(guan)路(lu)等。各種熱(re)交換器(qi)的管(guan)(guan)(guan)(guan)子(zi)大都采用(yong)(yong)無(wu)縫鋼(gang)(gang)管(guan)(guan)(guan)(guan)。中、低(di)壓(ya)管(guan)(guan)(guan)(guan)路(lu)無(wu)縫鋼(gang)(gang)管(guan)(guan)(guan)(guan)的最高(gao)工作溫度(du):碳(tan)鋼(gang)(gang)為(wei)250℃;優(you)質(zhi)碳(tan)鋼(gang)(gang)(如(ru)10鋼(gang)(gang))為(wei)450℃.高(gao)壓(ya)管(guan)(guan)(guan)(guan)路(lu)均用(yong)(yong)優(you)質(zhi)碳(tan)鋼(gang)(gang)(20鋼(gang)(gang))制成的無(wu)縫鋼(gang)(gang)管(guan)(guan)(guan)(guan),最高(gao)工作溫度(du)為(wei)200℃。
輸送強腐(fu)蝕(shi)性或高溫的(de)介質時,采用不銹鋼、耐酸鋼或耐熱(re)鋼制的(de)無縫鋼管。這(zhe)種(zhong)無縫鋼管也(ye)可用熱(re)軋而成(cheng)或再冷拔成(cheng)尺寸較小(xiao)的(de)管子。熱(re)軋管的(de)規格:外徑為6~89mm,壁厚為1~7mm,長度為1.5~7m.耐熱(re)鋼管最(zui)高工(gong)作溫度為850℃。
輸送高壓水(shui)時,可以采(cai)用厚(hou)壁(bi)無縫鋼(gang)管,它的外徑為(wei)12~219mm,壁(bi)厚(hou)為(wei)3.5~40mm,長(chang)度(du)(du)為(wei)3~4m,最高工(gong)作溫(wen)度(du)(du)為(wei)375℃。
2. 鑄鐵管
鑄(zhu)(zhu)鐵管(guan)(guan)分(fen)為普通鑄(zhu)(zhu)鐵管(guan)(guan)和(he)硅鐵管(guan)(guan)兩類。
①. 普通鑄鐵管(guan)
一般(ban)用灰口鐵(tie)鑄(zhu)造(zao),耐蝕性(xing)好,但質脆(cui),不抗沖(chong)擊。常(chang)用于埋地給水管(guan)(guan)道(dao)、煤氣(qi)管(guan)(guan)道(dao)和室內排水管(guan)(guan)道(dao)。給水鑄(zhu)鐵(tie)管(guan)(guan)有(you)低壓(p=0.45MPa)、常(chang)壓(p=0.75MPa)和高壓(p=1MPa)三種,直徑50~1500mm,壁厚(hou)7.5~30mm,管(guan)(guan)長3m、4m、6m.管(guan)(guan)端形狀分承(cheng)插式(shi)(shi)和法蘭(lan)式(shi)(shi)兩種,其中以(yi)承(cheng)插式(shi)(shi)最常(chang)用。
排水鑄鐵管(guan)只有承(cheng)插式一種。直徑50~200mm,壁厚4~7mm,長(chang)度有0.5m、1m、1.5m、2m等多種,但一般為(wei)2m。排水鑄鐵管(guan)比給水鑄鐵管(guan)壁薄(bo),承(cheng)口也淺,使用時可根(gen)據外形加以判(pan)別。
②. 硅鐵管
可分為高(gao)硅(gui)鐵管(guan)(guan)和抗(kang)氯硅(gui)鐵管(guan)(guan)兩種。高(gao)硅(gui)鐵管(guan)(guan)能抵抗(kang)多種強酸(suan)的腐蝕,而含鉬的抗(kang)氯硅(gui)鑄(zhu)鐵可抵抗(kang)各種濃度和溫度的鹽酸(suan),因此是很(hen)好的耐腐蝕管(guan)(guan)材。高(gao)硅(gui)合(he)(he)金(jin)(jin)鑄(zhu)件(jian)硬(ying)度大,只能用(yong)金(jin)(jin)剛(gang)砂輪修磨或(huo)用(yong)硬(ying)質合(he)(he)金(jin)(jin)刀具(ju)來加(jia)工(gong)。高(gao)硅(gui)合(he)(he)金(jin)(jin)制件(jian)受到(dao)輕微敲擊、局(ju)部受熱或(huo)急劇冷(leng)卻時,皆(jie)易(yi)破裂,但(dan)是由于(yu)(yu)其耐腐蝕性好,所以廣泛應用(yong)于(yu)(yu)化工(gong)管(guan)(guan)路(lu)中。
高(gao)硅(gui)(gui)鑄(zhu)鐵(tie)管(guan)和(he)抗氯硅(gui)(gui)鑄(zhu)鐵(tie)管(guan)的內徑為32~300mm,壁厚(hou)為10~16mm,長度為150~2000mm.用(yong)(yong)(yong)于(yu)輸送公稱壓力低(di)于(yu)0.25MPa的腐蝕性(xing)(xing)介質(zhi)。硅(gui)(gui)鐵(tie)管(guan)的耐(nai)熱性(xing)(xing)能(neng)好,可達(da)900℃.硅(gui)(gui)鐵(tie)管(guan)的兩端有供連(lian)接(jie)用(yong)(yong)(yong)的凸(tu)肩,利用(yong)(yong)(yong)對(dui)開式(shi)的松套法蘭連(lian)接(jie)。
3. 紫(zi)銅管和黃(huang)銅管
紫銅(tong)(tong)管(guan)和黃銅(tong)(tong)管(guan)都是(shi)拔制或擠制而成的無縫管(guan),主要用(yong)于制造換(huan)熱設備、制氧設備中(zhong)的低溫管(guan)路以及機械(xie)設備中(zhong)的油管(guan)和控制系統(tong)的管(guan)路。
拔(ba)制紫(zi)(zi)銅(tong)管(guan)(guan)外(wai)徑(jing)為3~360mm,壁(bi)厚為0.5~10mm;壓(ya)制紫(zi)(zi)銅(tong)管(guan)(guan)外(wai)徑(jing)為30~280mm,壁(bi)厚為5~30mm.管(guan)(guan)長均(jun)為1~6m,隨管(guan)(guan)子外(wai)徑(jing)與制造方法而異。拔(ba)制的盤(pan)(pan)狀紫(zi)(zi)銅(tong)管(guan)(guan)直徑(jing)較小,每盤(pan)(pan)管(guan)(guan)子長度從(cong)十幾米至數十米,黃(huang)銅(tong)管(guan)(guan)外(wai)徑(jing)為3~195mm.當工(gong)作溫度高于250℃時,不宜在壓(ya)力下使用(yong)紫(zi)(zi)銅(tong)管(guan)(guan)和黃(huang)銅(tong)管(guan)(guan)。紫(zi)(zi)銅(tong)管(guan)(guan)和黃(huang)銅(tong)管(guan)(guan)可以(yi)采用(yong)焊接(jie)連接(jie)、法蘭(lan)連接(jie)和螺紋連接(jie)。
4. 鋁管(guan)
鋁管(guan)是拔制而(er)成的(de)(de)無(wu)縫鋁管(guan),它主要用來輸送濃硝酸、醋(cu)酸、甲酸及其他介質,但不能抗堿液。鋁管(guan)外徑為6~120mm,壁厚(hou)為1~10mm,管(guan)長可達(da)6m.當(dang)工作溫度高于160℃時,不宜在壓(ya)力下使用鋁管(guan)。鋁管(guan)的(de)(de)連接(jie)(jie)(jie)采(cai)用焊接(jie)(jie)(jie)連接(jie)(jie)(jie)和(he)法蘭連接(jie)(jie)(jie)。
5. 鉛管
鉛(qian)(qian)(qian)(qian)(qian)管(guan)對硫(liu)酸(suan)具有良好的耐蝕性,因此(ci)廣泛應用(yong)(yong)于(yu)硫(liu)酸(suan)工(gong)業中,但(dan)由于(yu)鉛(qian)(qian)(qian)(qian)(qian)管(guan)有強度(du)低(di)、密度(du)大(da)、抗熱性能(neng)差等缺(que)點,故近來已逐漸(jian)被各(ge)種耐酸(suan)合(he)金(jin)(jin)(jin)管(guan)與塑料(liao)管(guan)所(suo)代(dai)替(ti)。鉛(qian)(qian)(qian)(qian)(qian)管(guan)的內徑(jing)為8~150mm,壁厚為2~10mm.內徑(jing)小(xiao)于(yu)55mm的鉛(qian)(qian)(qian)(qian)(qian)管(guan)多制成(cheng)(cheng)盤管(guan),內徑(jing)大(da)于(yu)60mm時才做成(cheng)(cheng)直(zhi)(zhi)管(guan),每根(gen)長(chang)2~2.5m.由于(yu)鉛(qian)(qian)(qian)(qian)(qian)易于(yu)輾壓、鍛制和焊(han)接,所(suo)以(yi)大(da)直(zhi)(zhi)徑(jing)的鉛(qian)(qian)(qian)(qian)(qian)管(guan)很容易用(yong)(yong)鉛(qian)(qian)(qian)(qian)(qian)板焊(han)制而成(cheng)(cheng);也(ye)可以(yi)在鉛(qian)(qian)(qian)(qian)(qian)中加入8%~10%的銻,而形成(cheng)(cheng)鉛(qian)(qian)(qian)(qian)(qian)銻合(he)金(jin)(jin)(jin),此(ci)合(he)金(jin)(jin)(jin)通常稱為硬(ying)鉛(qian)(qian)(qian)(qian)(qian),它可用(yong)(yong)于(yu)鑄造(zao)鉛(qian)(qian)(qian)(qian)(qian)管(guan)。
鉛管的連(lian)接可采用焊(han)接連(lian)接和法蘭連(lian)接。工(gong)作溫度高于140℃時,就不宜(yi)在壓力下使用鉛管。

