20號無縫鋼管在100℃與225℃溫度(temperature)的許(xu)應力的區別(bie)
20號鋼(gang)許用應力：20號鋼(gang)在(zai)225℃下的(de)許用應力：(16-36mm)111-124MPa之間(jian);(6-16mm)之間(jian)117-131MPa
20號鋼在100℃下的許用(yong)應力：150℃時,20號鋼鋼管的許用(yong)應力為130 MPa,20號鋼鍛件的許用(yong)應力為108MPa
無縫鋼管用途很廣泛(extensive)。一般用途的無縫鋼管由普通的碳(C)素結(jie)(jie)構(gou)(Structure)鋼(gang)、低合(he)金(jin)(jin)結(jie)(jie)構(gou)鋼(gang)或合(he)金(jin)(jin)結(jie)(jie)構(gou)鋼(gang)軋制，產量最(zui)多，主要用作輸送流體(ti)的管道或結(jie)(jie)構(gou)零(ling)件。2、根據用途不同(tong)分三類(lei)供應：
A、按化學(Chemistry)成分(ingredient)和機(ji)械(xie)(machinery)性能(xìng néng)供應;
B、按機械(machinery)性能(xìng néng)供應;
C、按水壓(ya)試(shi)驗供應。GB9948無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan)主要用(yong)(yong)來生產氣(qi)動或液壓(ya) 元件的(de)產品，如氣(qi)缸或油缸，都是用(yong)(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)管(guan)。精密無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan)的(de)化(hua)學成分(fen)有(you)碳C、硅Si、錳Mn、硫S、磷P、鉻Cr。GB5310無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan)按照用(yong)(yong)途分(fen)為結構用(yong)(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan);輸送用(yong)(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan);鍋(guo)爐(lu)用(yong)(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan);鍋(guo)爐(lu)用(yong)(yong)高壓(ya)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan).無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan)按照斷面形狀(zhuang)(zhuang)，無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)鋼(gang)管(guan)分(fen)圓形和異(yi)(yi)形兩種(zhong)，異(yi)(yi)形管(guan)有(you)方(fang)形、橢圓形、三(san)角形、六角形、瓜子形、星形、 帶翅管(guan)多種(zhong)復雜形狀(zhuang)(zhuang)。按
A、b類供(gong)應(ying)的(de)(de)鋼(gang)管(guan)，如(ru)用(yong)(yong)于承(cheng)受液體壓(ya)(ya)力(li)(pressure)，也(ye)要(yao)進(jin)行水壓(ya)(ya)(特指(zhi):壓(ya)(ya)強(qiang))試驗。3、專門用(yong)(yong)途(tu)的(de)(de)無(wu)(wu)(wu)縫管(guan)有(you)鍋爐(Boilers)用(yong)(yong)無(wu)(wu)(wu)縫管(guan)、化(hua)工電力(li)用(yong)(yong)，地質用(yong)(yong)無(wu)(wu)(wu)縫鋼(gang)管(guan)及(ji)石油(you)(petroleum)用(yong)(yong)無(wu)(wu)(wu)縫管(guan)等(deng)多(duo)種(zhong)。 無(wu)(wu)(wu)縫鋼(gang)管(guan)具有(you)中空(zhōng kōng)截面，大量用(yong)(yong)作輸送流體的(de)(de)管(guan)道(dao)(dao)(Conduit)，如(ru)輸送石油(you)、天(tian)然(natural)氣、煤(mei)氣(Coal Gas)、水及(ji)某些固體物(wu)料(liao)(liao)的(de)(de)管(guan)道(dao)(dao)等(deng)。鋼(gang)管(guan)與圓(yuan)鋼(gang)等(deng)實心鋼(gang)材(cai)相(xiang)比(bi)，在抗(kang)彎抗(kang)扭強(qiang)度(strength)相(xiang)同時，重(zhong)量較輕，是(shi)一種(zhong)經濟(Economy)截面鋼(gang)材(cai)。 廣泛(extensive)用(yong)(yong)于制(zhi)造(zhì zào)結(jie)構(Structure)件(jian)和機械(xie)(machinery)零(ling)(ling)件(jian)，如(ru)石油(you)鉆(zhan)桿、汽車(auto)傳動軸(zhou)(zhou)(傳動軸(zhou)(zhou)組成(cheng):軸(zhou)(zhou)管(guan)、伸縮套和萬向節(jie))、自行車架(jia)以及(ji)建(jian)筑(Architecture)施工中用(yong)(yong)的(de)(de)鋼(gang)腳手架(jia)等(deng)用(yong)(yong)鋼(gang)管(guan)制(zhi)造環形(xing)零(ling)(ling)件(jian)，可提高材(cai)料(liao)(liao)(Material)利用(yong)(yong)率(availability)，簡化(hua)制(zhi)造工序，節(jie)約材(cai)料(liao)(liao)和加(jia)工(Processing)工時，已廣泛用(yong)(yong)鋼(gang)管(guan)來制(zhi)造。
