20號無縫鋼管在100℃與(yu)225℃溫(wen)度(temperature)的許應力的區別
20號鋼許用應力(li)：20號鋼在225℃下(xia)的(de)許用應力(li)：(16-36mm)111-124MPa之間;(6-16mm)之間117-131MPa
20號(hao)鋼在100℃下(xia)的(de)(de)許用(yong)應(ying)力(li)：150℃時(shi),20號(hao)鋼鋼管的(de)(de)許用(yong)應(ying)力(li)為(wei)130 MPa,20號(hao)鋼鍛件的(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(tong)的碳(tan)(C)素結構(Structure)鋼、低合金結構鋼或合金結構鋼軋(ya)制，產量(liang)最(zui)多，主要用作(zuo)輸(shu)送流(liu)體的管道或結構零件。2、根據用途不(bu)同分三類(lei)供應：
A、按化(hua)學(Chemistry)成分(ingredient)和(he)機械(machinery)性能(xìng néng)供應;
B、按機械(machinery)性能(xìng néng)供應;
C、按(an)(an)水壓(ya)試驗(yan)供應(ying)。GB9948無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)主要用(yong)(yong)來生產氣(qi)動或(huo)液壓(ya) 元(yuan)件的(de)產品，如(ru)氣(qi)缸(gang)或(huo)油缸(gang)，都是用(yong)(yong)無(wu)(wu)縫(feng)管(guan)(guan)(guan)(guan)(guan)。精密無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)的(de)化學成分有(you)碳C、硅Si、錳Mn、硫S、磷P、鉻Cr。GB5310無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)按(an)(an)照用(yong)(yong)途分為結構(gou)用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan);輸送用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan);鍋(guo)爐用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan);鍋(guo)爐用(yong)(yong)高壓(ya)無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan).無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)按(an)(an)照斷面形(xing)狀，無(wu)(wu)縫(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)分圓(yuan)形(xing)和異形(xing)兩(liang)種，異形(xing)管(guan)(guan)(guan)(guan)(guan)有(you)方形(xing)、橢圓(yuan)形(xing)、三角形(xing)、六角形(xing)、瓜子形(xing)、星形(xing)、 帶(dai)翅管(guan)(guan)(guan)(guan)(guan)多種復(fu)雜形(xing)狀。按(an)(an)
A、b類(lei)供應的(de)鋼(gang)(gang)管(guan)(guan)，如(ru)用(yong)于(yu)承受(shou)液體(ti)(ti)壓(ya)力(pressure)，也(ye)要進行水(shui)壓(ya)(特(te)指:壓(ya)強)試驗。3、專門用(yong)途(tu)的(de)無(wu)縫(feng)(feng)管(guan)(guan)有(you)鍋爐(Boilers)用(yong)無(wu)縫(feng)(feng)管(guan)(guan)、化工(gong)電力用(yong)，地質用(yong)無(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)及石油(you)(petroleum)用(yong)無(wu)縫(feng)(feng)管(guan)(guan)等多(duo)種(zhong)。 無(wu)縫(feng)(feng)鋼(gang)(gang)管(guan)(guan)具(ju)有(you)中空(kong)(zhōng kōng)截面(mian)，大量用(yong)作輸送(song)流體(ti)(ti)的(de)管(guan)(guan)道(dao)(Conduit)，如(ru)輸送(song)石油(you)、天(tian)然(ran)(natural)氣、煤(mei)氣(Coal Gas)、水(shui)及某些固體(ti)(ti)物(wu)料的(de)管(guan)(guan)道(dao)等。鋼(gang)(gang)管(guan)(guan)與(yu)圓鋼(gang)(gang)等實(shi)心(xin)鋼(gang)(gang)材相比，在抗(kang)彎抗(kang)扭強度(strength)相同時(shi)，重量較(jiao)輕，是一種(zhong)經濟(Economy)截面(mian)鋼(gang)(gang)材。 廣(guang)泛(extensive)用(yong)于(yu)制(zhi)(zhi)造(zao)(zao)(zhì zào)結構(Structure)件和(he)機械(machinery)零件，如(ru)石油(you)鉆桿、汽車(auto)傳(chuan)動軸(zhou)(傳(chuan)動軸(zhou)組成:軸(zhou)管(guan)(guan)、伸縮(suo)套和(he)萬向節(jie)(jie))、自行車架以及建筑(Architecture)施工(gong)中用(yong)的(de)鋼(gang)(gang)腳手(shou)架等用(yong)鋼(gang)(gang)管(guan)(guan)制(zhi)(zhi)造(zao)(zao)環形零件，可提高材料(Material)利(li)用(yong)率(availability)，簡(jian)化制(zhi)(zhi)造(zao)(zao)工(gong)序，節(jie)(jie)約(yue)材料和(he)加工(gong)(Processing)工(gong)時(shi)，已廣(guang)泛用(yong)鋼(gang)(gang)管(guan)(guan)來(lai)制(zhi)(zhi)造(zao)(zao)。
