20號無縫鋼管在(zai)100℃與225℃溫度(temperature)的許應(ying)力(li)的區別
20號鋼許用應力(li)：20號鋼在(zai)225℃下(xia)的許用應力(li)：(16-36mm)111-124MPa之間;(6-16mm)之間117-131MPa
20號(hao)(hao)鋼(gang)(gang)在100℃下的(de)(de)許用(yong)應(ying)力(li)：150℃時,20號(hao)(hao)鋼(gang)(gang)鋼(gang)(gang)管的(de)(de)許用(yong)應(ying)力(li)為(wei)130 MPa,20號(hao)(hao)鋼(gang)(gang)鍛件的(de)(de)許用(yong)應(ying)力(li)為(wei)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)素結構(Structure)鋼、低合金結構鋼或合金結構鋼軋制，產(chan)量最多，主要用(yong)作輸(shu)送(song)流體的管道或結構零件。2、根據用(yong)途不同分(fen)三類供應：
A、按化學(Chemistry)成分(fen)(ingredient)和機械(machinery)性能(xìng néng)供應;
B、按機械(machinery)性能(xìng néng)供應;
C、按(an)水(shui)壓(ya)試(shi)驗供應。GB9948無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan)主要用(yong)來生產氣(qi)動(dong)或液壓(ya) 元件的產品，如氣(qi)缸或油缸，都是用(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)管(guan)(guan)(guan)。精密無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan)的化(hua)學成分有(you)碳C、硅Si、錳Mn、硫(liu)S、磷(lin)P、鉻Cr。GB5310無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan)按(an)照用(yong)途分為結構用(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan);輸送用(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan);鍋爐(lu)用(yong)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan);鍋爐(lu)用(yong)高壓(ya)無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan).無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan)按(an)照斷面形(xing)(xing)(xing)狀，無(wu)(wu)(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)(gang)(gang)管(guan)(guan)(guan)分圓形(xing)(xing)(xing)和異形(xing)(xing)(xing)兩種，異形(xing)(xing)(xing)管(guan)(guan)(guan)有(you)方形(xing)(xing)(xing)、橢圓形(xing)(xing)(xing)、三(san)角形(xing)(xing)(xing)、六角形(xing)(xing)(xing)、瓜子形(xing)(xing)(xing)、星形(xing)(xing)(xing)、 帶翅管(guan)(guan)(guan)多種復雜形(xing)(xing)(xing)狀。按(an)
A、b類供應(ying)的鋼(gang)(gang)管(guan)(guan)(guan)，如用(yong)于承受液體(ti)(ti)壓(ya)力(li)(pressure)，也要(yao)進行水壓(ya)(特(te)指:壓(ya)強)試驗。3、專(zhuan)門用(yong)途(tu)的無(wu)縫(feng)(feng)(feng)管(guan)(guan)(guan)有(you)鍋爐(lu)(Boilers)用(yong)無(wu)縫(feng)(feng)(feng)管(guan)(guan)(guan)、化工(gong)電(dian)力(li)用(yong)，地質用(yong)無(wu)縫(feng)(feng)(feng)鋼(gang)(gang)管(guan)(guan)(guan)及(ji)(ji)石油(you)(you)(petroleum)用(yong)無(wu)縫(feng)(feng)(feng)管(guan)(guan)(guan)等多種(zhong)。 無(wu)縫(feng)(feng)(feng)鋼(gang)(gang)管(guan)(guan)(guan)具有(you)中(zhong)空(kong)(zhōng kōng)截面(mian)(mian)，大量用(yong)作輸(shu)送(song)流(liu)體(ti)(ti)的管(guan)(guan)(guan)道(Conduit)，如輸(shu)送(song)石油(you)(you)、天然(natural)氣、煤氣(Coal Gas)、水及(ji)(ji)某(mou)些固體(ti)(ti)物料的管(guan)(guan)(guan)道等。鋼(gang)(gang)管(guan)(guan)(guan)與圓鋼(gang)(gang)等實心(xin)鋼(gang)(gang)材(cai)相(xiang)比，在(zai)抗彎抗扭(niu)強度(strength)相(xiang)同(tong)時，重量較輕，是一種(zhong)經濟(Economy)截面(mian)(mian)鋼(gang)(gang)材(cai)。 廣(guang)泛(fan)(extensive)用(yong)于制造(zao)(zhì zào)結構(Structure)件(jian)和機械(machinery)零件(jian)，如石油(you)(you)鉆(zhan)桿、汽車(auto)傳動軸(傳動軸組成(cheng):軸管(guan)(guan)(guan)、伸縮套和萬(wan)向節(jie))、自行車架以及(ji)(ji)建(jian)筑(Architecture)施工(gong)中(zhong)用(yong)的鋼(gang)(gang)腳手架等用(yong)鋼(gang)(gang)管(guan)(guan)(guan)制造(zao)環形零件(jian)，可(ke)提(ti)高材(cai)料(Material)利用(yong)率(availability)，簡(jian)化制造(zao)工(gong)序，節(jie)約材(cai)料和加工(gong)(Processing)工(gong)時，已廣(guang)泛(fan)用(yong)鋼(gang)(gang)管(guan)(guan)(guan)來(lai)制造(zao)。
