20號無縫鋼管在100℃與225℃溫(wen)度(du)(temperature)的許應力的區別
20號(hao)鋼許用應力：20號(hao)鋼在225℃下的許用應力：(16-36mm)111-124MPa之(zhi)間(jian);(6-16mm)之(zhi)間(jian)117-131MPa
20號鋼在100℃下的許用應力(li)：150℃時,20號鋼鋼管的許用應力(li)為130 MPa,20號鋼鍛件的許用應力(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的碳(C)素(su)結(jie)構(gou)(gou)(Structure)鋼、低(di)合(he)金(jin)結(jie)構(gou)(gou)鋼或合(he)金(jin)結(jie)構(gou)(gou)鋼軋制，產量(liang)最多，主要用作(zuo)輸(shu)送流(liu)體的管道(dao)或結(jie)構(gou)(gou)零件。2、根據(ju)用途不(bu)同分三類供應：
A、按(an)化(hua)學(Chemistry)成分(ingredient)和(he)機械(machinery)性能(xìng néng)供(gong)應(ying);
B、按機械(machinery)性能(xìng néng)供應(ying);
C、按水壓(ya)試驗供應(ying)。GB9948無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)主要用(yong)來生(sheng)產氣動或液壓(ya) 元件的產品(pin)，如氣缸或油缸，都是用(yong)無(wu)(wu)(wu)縫(feng)(feng)管(guan)(guan)。精密(mi)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)的化學成分有碳(tan)C、硅Si、錳Mn、硫S、磷P、鉻Cr。GB5310無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)按照用(yong)途分為(wei)結構用(yong)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan);輸送用(yong)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan);鍋爐(lu)用(yong)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan);鍋爐(lu)用(yong)高(gao)壓(ya)無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan).無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)按照斷面形(xing)(xing)(xing)狀(zhuang)，無(wu)(wu)(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)分圓形(xing)(xing)(xing)和異(yi)(yi)形(xing)(xing)(xing)兩種，異(yi)(yi)形(xing)(xing)(xing)管(guan)(guan)有方形(xing)(xing)(xing)、橢圓形(xing)(xing)(xing)、三角形(xing)(xing)(xing)、六角形(xing)(xing)(xing)、瓜(gua)子(zi)形(xing)(xing)(xing)、星形(xing)(xing)(xing)、 帶翅管(guan)(guan)多(duo)種復(fu)雜(za)形(xing)(xing)(xing)狀(zhuang)。按
A、b類供應的(de)(de)(de)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)，如用(yong)(yong)(yong)于承受液體壓力(li)(pressure)，也要進行水(shui)壓(特(te)指:壓強(qiang))試驗。3、專門用(yong)(yong)(yong)途的(de)(de)(de)無(wu)縫管(guan)(guan)(guan)(guan)(guan)有鍋爐(Boilers)用(yong)(yong)(yong)無(wu)縫管(guan)(guan)(guan)(guan)(guan)、化工(gong)(gong)電力(li)用(yong)(yong)(yong)，地質用(yong)(yong)(yong)無(wu)縫鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)及石(shi)油(you)(petroleum)用(yong)(yong)(yong)無(wu)縫管(guan)(guan)(guan)(guan)(guan)等(deng)(deng)多種。 無(wu)縫鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)具有中空(kong)(zhōng kōng)截(jie)面，大(da)量用(yong)(yong)(yong)作輸(shu)送流體的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)道(dao)(Conduit)，如輸(shu)送石(shi)油(you)、天然(natural)氣、煤氣(Coal Gas)、水(shui)及某些固體物料的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)道(dao)等(deng)(deng)。鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)與圓(yuan)鋼(gang)(gang)(gang)等(deng)(deng)實心鋼(gang)(gang)(gang)材(cai)相比，在抗彎抗扭(niu)強(qiang)度(strength)相同時(shi)，重(zhong)量較輕(qing)，是一種經濟(Economy)截(jie)面鋼(gang)(gang)(gang)材(cai)。 廣(guang)泛(fan)(extensive)用(yong)(yong)(yong)于制造(zhì zào)結(jie)構(Structure)件和(he)機械(machinery)零(ling)件，如石(shi)油(you)鉆(zhan)桿、汽車(auto)傳(chuan)動(dong)軸(傳(chuan)動(dong)軸組成(cheng):軸管(guan)(guan)(guan)(guan)(guan)、伸(shen)縮套(tao)和(he)萬向節)、自行車架以及建筑(zhu)(Architecture)施工(gong)(gong)中用(yong)(yong)(yong)的(de)(de)(de)鋼(gang)(gang)(gang)腳手架等(deng)(deng)用(yong)(yong)(yong)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)制造環形零(ling)件，可提高材(cai)料(Material)利用(yong)(yong)(yong)率(availability)，簡化制造工(gong)(gong)序，節約材(cai)料和(he)加工(gong)(gong)(Processing)工(gong)(gong)時(shi)，已廣(guang)泛(fan)用(yong)(yong)(yong)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)(guan)來制造。
