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(gang)管
鋼管分(fen)為有(you)縫(feng)(feng)鋼管和(he)無縫(feng)(feng)鋼管兩(liang)大類(lei)。
①. 有縫(feng)鋼管(guan)又稱(cheng)為(wei)焊接鋼管(guan)
可分(fen)為低壓(ya)流體輸(shu)送(song)鋼管(guan)和(he)電(dian)焊鋼管(guan)兩類(lei)。低壓(ya)流體輸(shu)送(song)鋼管(guan)是(shi)由扁鋼管(guan)坯卷(juan)成管(guan)形并沿縫焊接而成的,因(yin)為它常用(yong)來輸(shu)送(song)水(shui)和(he)煤(mei)氣,故俗稱為水(shui)煤(mei)氣管(guan)。水(shui)煤(mei)氣管(guan)可分(fen)為鍍(du)鋅(xin)的和(he)不鍍(du)鋅(xin)的;普通的和(he)加厚的;帶(dai)螺紋(wen)的和(he)不帶(dai)螺紋(wen)的等類(lei)型(xing)。
水(shui)煤氣(qi)鋼(gang)管(guan)廣泛應用在小直(zhi)徑的(de)低(di)壓(ya)(ya)(ya)(ya)管(guan)路上,如給(gei)水(shui)、煤氣(qi)、暖(nuan)氣(qi)、壓(ya)(ya)(ya)(ya)縮空氣(qi)、蒸汽、凝結水(shui)、廢氣(qi)、真空及某些物料管(guan)路。普通鋼(gang)管(guan)正(zheng)常(chang)(chang)工作壓(ya)(ya)(ya)(ya)力(li)(li)不大(da)于0.6MPa(表(biao)壓(ya)(ya)(ya)(ya));加厚鋼(gang)管(guan)正(zheng)常(chang)(chang)工作壓(ya)(ya)(ya)(ya)力(li)(li)不大(da)于1MPa(表(biao)壓(ya)(ya)(ya)(ya))。正(zheng)常(chang)(chang)工作溫度不宜超過175℃。最大(da)水(shui)壓(ya)(ya)(ya)(ya)試驗壓(ya)(ya)(ya)(ya)力(li)(li):普通鋼(gang)管(guan)為(wei)2MPa,加厚鋼(gang)管(guan)為(wei)3MPa。
電焊(han)(han)(han)鋼(gang)(gang)管是由軟鋼(gang)(gang)板條(tiao)卷(juan)成管形后焊(han)(han)(han)接而成的鋼(gang)(gang)管,分直焊(han)(han)(han)縫和螺(luo)旋焊(han)(han)(han)縫兩種類型。
直焊(han)(han)縫(feng)的電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan),又可(ke)分(fen)為(wei)(wei)(wei)小(xiao)直徑(jing)電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)和大(da)直徑(jing)電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)兩類。小(xiao)直徑(jing)的電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)外徑(jing)為(wei)(wei)(wei)5~152mm,壁(bi)厚(hou)(hou)為(wei)(wei)(wei)0.5~5.5mm.大(da)直徑(jing)的電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)又稱鋼(gang)(gang)(gang)板卷管(guan),其外徑(jing)為(wei)(wei)(wei)530~2020mm,壁(bi)厚(hou)(hou)為(wei)(wei)(wei)4~16mm.螺(luo)旋縫(feng)電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)外徑(jing)為(wei)(wei)(wei)219~720mm,壁(bi)厚(hou)(hou)為(wei)(wei)(wei)6~7mm.電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)可(ke)用(yong)于壓力不高或無嚴格要求的管(guan)路(lu)上。電(dian)(dian)(dian)焊(han)(han)鋼(gang)(gang)(gang)管(guan)的正(zheng)常工作(zuo)溫(wen)度不宜超(chao)過200℃。
②. 無縫鋼(gang)管
是由圓鋼(gang)坯加熱后,經(jing)(jing)穿管(guan)機(ji)穿孔軋制(熱軋)而成的或者再經(jing)(jing)過冷拔而成為(wei)(wei)外徑(jing)較小的管(guan)子(zi),因為(wei)(wei)它沒有接縫,所(suo)以稱為(wei)(wei)無(wu)縫鋼(gang)管(guan)。
無縫(feng)(feng)鋼(gang)管(guan)按(an)照制造方法的(de)(de)不同,又分為(wei)熱軋無縫(feng)(feng)鋼(gang)管(guan)和冷拔無縫(feng)(feng)鋼(gang)管(guan)兩類。熱軋無縫(feng)(feng)鋼(gang)管(guan)的(de)(de)規格:外徑為(wei)32~630mm,壁(bi)厚為(wei)2.5~75mm,管(guan)長(chang)為(wei)4~12.5m;冷拔無縫(feng)(feng)鋼(gang)管(guan)的(de)(de)規格:外徑為(wei)2~150mm,壁(bi)厚為(wei)0.25~14mm,管(guan)長(chang)為(wei)1.5~9m。
無(wu)縫鋼(gang)(gang)管(guan)(guan)強(qiang)度(du)(du)高(gao),可用在重要管(guan)(guan)路(lu)上,如高(gao)壓蒸汽和(he)過(guo)熱(re)(re)蒸汽的(de)(de)管(guan)(guan)路(lu)、高(gao)壓水和(he)過(guo)熱(re)(re)水管(guan)(guan)路(lu)、高(gao)壓氣體(ti)和(he)液(ye)體(ti)管(guan)(guan)路(lu)以(yi)及輸送(song)燃燒(shao)性(xing)、爆(bao)炸性(xing)和(he)有毒害(hai)性(xing)的(de)(de)物料管(guan)(guan)路(lu)等。各種熱(re)(re)交換器(qi)的(de)(de)管(guan)(guan)子大都采用無(wu)縫鋼(gang)(gang)管(guan)(guan)。中、低(di)壓管(guan)(guan)路(lu)無(wu)縫鋼(gang)(gang)管(guan)(guan)的(de)(de)最(zui)高(gao)工作溫(wen)度(du)(du):碳鋼(gang)(gang)為(wei)250℃;優質碳鋼(gang)(gang)(如10鋼(gang)(gang))為(wei)450℃.高(gao)壓管(guan)(guan)路(lu)均(jun)用優質碳鋼(gang)(gang)(20鋼(gang)(gang))制(zhi)成(cheng)的(de)(de)無(wu)縫鋼(gang)(gang)管(guan)(guan),最(zui)高(gao)工作溫(wen)度(du)(du)為(wei)200℃。
輸送強腐蝕(shi)性(xing)或(huo)高溫(wen)(wen)的介質時,采(cai)用(yong)不(bu)銹鋼、耐(nai)酸鋼或(huo)耐(nai)熱鋼制的無(wu)縫鋼管(guan)。這(zhe)種無(wu)縫鋼管(guan)也可用(yong)熱軋而成(cheng)或(huo)再冷拔成(cheng)尺寸較小的管(guan)子。熱軋管(guan)的規格(ge):外徑為6~89mm,壁厚為1~7mm,長度(du)為1.5~7m.耐(nai)熱鋼管(guan)最高工作(zuo)溫(wen)(wen)度(du)為850℃。
輸(shu)送高(gao)壓水時(shi),可以采用厚壁無縫鋼(gang)管,它的外徑為(wei)12~219mm,壁厚為(wei)3.5~40mm,長度為(wei)3~4m,最高(gao)工作溫(wen)度為(wei)375℃。
2. 鑄鐵管(guan)
鑄鐵(tie)管分為普通鑄鐵(tie)管和硅鐵(tie)管兩(liang)類。
①. 普通鑄鐵管
一(yi)般用灰(hui)口鐵鑄造,耐(nai)蝕性好,但質脆,不抗沖擊。常(chang)用于埋(mai)地(di)給水(shui)(shui)管(guan)(guan)道、煤氣管(guan)(guan)道和(he)(he)室內排(pai)水(shui)(shui)管(guan)(guan)道。給水(shui)(shui)鑄鐵管(guan)(guan)有低壓(ya)(p=0.45MPa)、常(chang)壓(ya)(p=0.75MPa)和(he)(he)高壓(ya)(p=1MPa)三(san)種,直(zhi)徑50~1500mm,壁厚(hou)7.5~30mm,管(guan)(guan)長3m、4m、6m.管(guan)(guan)端形狀分承插(cha)式和(he)(he)法蘭式兩(liang)種,其中以承插(cha)式最常(chang)用。
排(pai)水(shui)(shui)鑄(zhu)(zhu)鐵(tie)(tie)管只有(you)(you)承(cheng)插式一種(zhong)。直徑50~200mm,壁(bi)厚4~7mm,長度有(you)(you)0.5m、1m、1.5m、2m等(deng)多種(zhong),但一般為2m。排(pai)水(shui)(shui)鑄(zhu)(zhu)鐵(tie)(tie)管比(bi)給水(shui)(shui)鑄(zhu)(zhu)鐵(tie)(tie)管壁(bi)薄,承(cheng)口(kou)也淺,使(shi)用時(shi)可根據外形加(jia)以判別(bie)。
②. 硅鐵管
可分為(wei)高硅(gui)鐵(tie)管和抗氯硅(gui)鐵(tie)管兩種(zhong)。高硅(gui)鐵(tie)管能抵抗多種(zhong)強酸的(de)腐蝕(shi),而含鉬的(de)抗氯硅(gui)鑄鐵(tie)可抵抗各(ge)種(zhong)濃度(du)和溫度(du)的(de)鹽(yan)酸,因此(ci)是很好(hao)的(de)耐腐蝕(shi)管材。高硅(gui)合(he)金(jin)(jin)鑄件硬度(du)大,只能用金(jin)(jin)剛砂輪修磨或用硬質合(he)金(jin)(jin)刀具(ju)來加工。高硅(gui)合(he)金(jin)(jin)制(zhi)件受(shou)到輕微敲擊(ji)、局部受(shou)熱或急(ji)劇冷卻時,皆易破裂,但是由于其耐腐蝕(shi)性好(hao),所以(yi)廣泛(fan)應用于化工管路(lu)中(zhong)。
高(gao)硅鑄(zhu)鐵(tie)(tie)管(guan)(guan)和抗氯硅鑄(zhu)鐵(tie)(tie)管(guan)(guan)的內徑(jing)為(wei)32~300mm,壁厚(hou)為(wei)10~16mm,長度(du)為(wei)150~2000mm.用(yong)于輸送公稱壓力(li)低于0.25MPa的腐蝕性介質。硅鐵(tie)(tie)管(guan)(guan)的耐熱性能(neng)好,可達900℃.硅鐵(tie)(tie)管(guan)(guan)的兩(liang)端有供連接(jie)用(yong)的凸(tu)肩,利用(yong)對開式(shi)的松套法蘭連接(jie)。
3. 紫銅管和黃(huang)銅管
紫(zi)銅管(guan)和黃(huang)銅管(guan)都是(shi)拔制(zhi)(zhi)或擠制(zhi)(zhi)而成的(de)無縫(feng)管(guan),主要(yao)用(yong)于(yu)制(zhi)(zhi)造換熱設備、制(zhi)(zhi)氧設備中(zhong)的(de)低溫管(guan)路以及機(ji)械設備中(zhong)的(de)油管(guan)和控制(zhi)(zhi)系統的(de)管(guan)路。
拔制紫(zi)銅(tong)(tong)管(guan)外徑為(wei)(wei)3~360mm,壁(bi)厚為(wei)(wei)0.5~10mm;壓(ya)制紫(zi)銅(tong)(tong)管(guan)外徑為(wei)(wei)30~280mm,壁(bi)厚為(wei)(wei)5~30mm.管(guan)長均(jun)為(wei)(wei)1~6m,隨管(guan)子(zi)外徑與制造方(fang)法(fa)而異。拔制的盤狀紫(zi)銅(tong)(tong)管(guan)直徑較小,每(mei)盤管(guan)子(zi)長度(du)(du)從十幾米至數十米,黃銅(tong)(tong)管(guan)外徑為(wei)(wei)3~195mm.當工作溫度(du)(du)高于(yu)250℃時,不宜在(zai)壓(ya)力下使用紫(zi)銅(tong)(tong)管(guan)和(he)黃銅(tong)(tong)管(guan)。紫(zi)銅(tong)(tong)管(guan)和(he)黃銅(tong)(tong)管(guan)可以采用焊接(jie)連(lian)接(jie)、法(fa)蘭連(lian)接(jie)和(he)螺紋連(lian)接(jie)。
4. 鋁(lv)管
鋁(lv)管(guan)(guan)(guan)是拔制而成的無縫鋁(lv)管(guan)(guan)(guan),它主要用(yong)來輸送(song)濃硝酸(suan)、醋酸(suan)、甲酸(suan)及(ji)其他介質,但不能抗堿液。鋁(lv)管(guan)(guan)(guan)外(wai)徑(jing)為6~120mm,壁厚為1~10mm,管(guan)(guan)(guan)長(chang)可(ke)達6m.當工作溫度高于160℃時,不宜(yi)在壓力(li)下使用(yong)鋁(lv)管(guan)(guan)(guan)。鋁(lv)管(guan)(guan)(guan)的連(lian)(lian)接(jie)(jie)采用(yong)焊接(jie)(jie)連(lian)(lian)接(jie)(jie)和法蘭(lan)連(lian)(lian)接(jie)(jie)。
5. 鉛管
鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)對硫酸具(ju)有(you)良好的(de)耐蝕性,因此(ci)(ci)廣泛(fan)應(ying)用(yong)于(yu)(yu)硫酸工業中(zhong),但由于(yu)(yu)鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)有(you)強(qiang)度低、密度大(da)、抗熱性能(neng)差等缺點,故近來已逐漸(jian)被各種(zhong)耐酸合(he)(he)金(jin)(jin)管(guan)(guan)與(yu)塑料(liao)管(guan)(guan)所(suo)代替。鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)的(de)內徑(jing)為8~150mm,壁厚為2~10mm.內徑(jing)小(xiao)于(yu)(yu)55mm的(de)鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)多制(zhi)成盤管(guan)(guan),內徑(jing)大(da)于(yu)(yu)60mm時才做成直(zhi)管(guan)(guan),每根長2~2.5m.由于(yu)(yu)鉛(qian)(qian)(qian)(qian)(qian)易(yi)于(yu)(yu)輾壓、鍛(duan)制(zhi)和焊(han)接,所(suo)以大(da)直(zhi)徑(jing)的(de)鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)很容易(yi)用(yong)鉛(qian)(qian)(qian)(qian)(qian)板(ban)焊(han)制(zhi)而(er)成;也可以在(zai)鉛(qian)(qian)(qian)(qian)(qian)中(zhong)加入(ru)8%~10%的(de)銻,而(er)形成鉛(qian)(qian)(qian)(qian)(qian)銻合(he)(he)金(jin)(jin),此(ci)(ci)合(he)(he)金(jin)(jin)通常稱為硬鉛(qian)(qian)(qian)(qian)(qian),它可用(yong)于(yu)(yu)鑄造鉛(qian)(qian)(qian)(qian)(qian)管(guan)(guan)。
鉛管(guan)的連接可(ke)采用焊接連接和法蘭連接。工(gong)作(zuo)溫度高于140℃時,就不宜在壓(ya)力下使(shi)用鉛管(guan)。