20號無縫鋼管在(zai)100℃與225℃溫(wen)度(du)(temperature)的(de)許(xu)應力的(de)區別
20號鋼許用(yong)應力：20號鋼在225℃下(xia)的許用(yong)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)(yong)應(ying)力(li)：150℃時,20號鋼鋼管的許用(yong)(yong)應(ying)力(li)為130 MPa,20號鋼鍛(duan)件的許用(yong)(yong)應(ying)力(li)為108MPa
無縫鋼管用途很廣泛(extensive)。一般用途的無縫鋼管由普通(tong)的碳(C)素結構(Structure)鋼(gang)、低合(he)金結構鋼(gang)或(huo)合(he)金結構鋼(gang)軋(ya)制，產量最多，主要用(yong)作輸送(song)流體的管道或(huo)結構零件。2、根據用(yong)途不同分(fen)三類供應(ying)：
A、按化(hua)學(Chemistry)成分(ingredient)和機械(machinery)性能(neng)(xìng néng)供應(ying);
B、按機械(xie)(machinery)性(xing)能(xìng néng)供應;
C、按(an)水壓(ya)試驗供(gong)應。GB9948無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan)主要用來生產氣動(dong)或液壓(ya) 元件的產品，如氣缸或油(you)缸，都是用無(wu)(wu)縫管(guan)(guan)。精密(mi)無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan)的化學成分(fen)有(you)碳(tan)C、硅Si、錳Mn、硫S、磷(lin)P、鉻Cr。GB5310無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan)按(an)照(zhao)用途分(fen)為結(jie)構用無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan);輸送(song)用無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan);鍋(guo)爐(lu)用無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan);鍋(guo)爐(lu)用高壓(ya)無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan).無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan)按(an)照(zhao)斷面(mian)形(xing)(xing)(xing)狀(zhuang)，無(wu)(wu)縫鋼(gang)(gang)(gang)(gang)管(guan)(guan)分(fen)圓(yuan)形(xing)(xing)(xing)和異形(xing)(xing)(xing)兩種，異形(xing)(xing)(xing)管(guan)(guan)有(you)方形(xing)(xing)(xing)、橢(tuo)圓(yuan)形(xing)(xing)(xing)、三角(jiao)形(xing)(xing)(xing)、六(liu)角(jiao)形(xing)(xing)(xing)、瓜子形(xing)(xing)(xing)、星形(xing)(xing)(xing)、 帶翅管(guan)(guan)多種復雜形(xing)(xing)(xing)狀(zhuang)。按(an)
A、b類供(gong)應(ying)的(de)鋼(gang)(gang)管(guan)(guan)(guan)(guan)，如用(yong)(yong)(yong)(yong)(yong)(yong)(yong)于承受(shou)液體(ti)(ti)壓力(pressure)，也要進行水壓(特指:壓強)試驗。3、專門用(yong)(yong)(yong)(yong)(yong)(yong)(yong)途的(de)無(wu)(wu)(wu)縫(feng)(feng)管(guan)(guan)(guan)(guan)有(you)鍋爐(Boilers)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)無(wu)(wu)(wu)縫(feng)(feng)管(guan)(guan)(guan)(guan)、化(hua)工(gong)電力用(yong)(yong)(yong)(yong)(yong)(yong)(yong)，地質(zhi)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)(guan)(guan)及石(shi)油(petroleum)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)無(wu)(wu)(wu)縫(feng)(feng)管(guan)(guan)(guan)(guan)等(deng)多種(zhong)。 無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)(guan)(guan)具(ju)有(you)中(zhong)空(zhōng kōng)截(jie)面，大量(liang)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)作輸送流體(ti)(ti)的(de)管(guan)(guan)(guan)(guan)道(Conduit)，如輸送石(shi)油、天然(natural)氣(qi)、煤氣(qi)(Coal Gas)、水及某些固體(ti)(ti)物料(liao)的(de)管(guan)(guan)(guan)(guan)道等(deng)。鋼(gang)(gang)管(guan)(guan)(guan)(guan)與圓鋼(gang)(gang)等(deng)實心鋼(gang)(gang)材(cai)相比，在抗彎抗扭強度(strength)相同時(shi)，重量(liang)較輕(qing)，是一種(zhong)經濟(Economy)截(jie)面鋼(gang)(gang)材(cai)。 廣泛(fan)(fan)(extensive)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)于制(zhi)造(zao)(zhì zào)結構(gou)(Structure)件(jian)和(he)機(ji)械(machinery)零件(jian)，如石(shi)油鉆桿、汽(qi)車(auto)傳動軸(zhou)(傳動軸(zhou)組(zu)成(cheng):軸(zhou)管(guan)(guan)(guan)(guan)、伸縮套和(he)萬向節)、自行車架(jia)以及建筑(Architecture)施工(gong)中(zhong)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)的(de)鋼(gang)(gang)腳(jiao)手架(jia)等(deng)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)鋼(gang)(gang)管(guan)(guan)(guan)(guan)制(zhi)造(zao)環形零件(jian)，可提高(gao)材(cai)料(liao)(Material)利用(yong)(yong)(yong)(yong)(yong)(yong)(yong)率(availability)，簡化(hua)制(zhi)造(zao)工(gong)序，節約材(cai)料(liao)和(he)加工(gong)(Processing)工(gong)時(shi)，已廣泛(fan)(fan)用(yong)(yong)(yong)(yong)(yong)(yong)(yong)鋼(gang)(gang)管(guan)(guan)(guan)(guan)來制(zhi)造(zao)。
