20號無縫鋼管在100℃與225℃溫度(temperature)的(de)許應力的(de)區別
20號鋼(gang)許用(yong)應(ying)力：20號鋼(gang)在225℃下的(de)許用(yong)應(ying)力：(16-36mm)111-124MPa之間(jian);(6-16mm)之間(jian)117-131MPa
20號(hao)鋼在100℃下的(de)(de)許用(yong)(yong)應力：150℃時,20號(hao)鋼鋼管的(de)(de)許用(yong)(yong)應力為(wei)130 MPa,20號(hao)鋼鍛件的(de)(de)許用(yong)(yong)應力為(wei)108MPa
無縫鋼管用途很廣泛(extensive)。一般用途的無縫鋼管由普(pu)通的(de)碳(tan)(C)素(su)結(jie)構(gou)(Structure)鋼(gang)、低合金結(jie)構(gou)鋼(gang)或(huo)合金結(jie)構(gou)鋼(gang)軋制，產量(liang)最多(duo)，主(zhu)要用(yong)作輸送流(liu)體(ti)的(de)管道或(huo)結(jie)構(gou)零件。2、根據(ju)用(yong)途(tu)不同(tong)分(fen)三類供(gong)應：
A、按化(hua)學(Chemistry)成分(fen)(ingredient)和機(ji)械(xie)(machinery)性能(xìng néng)供應;
B、按機械(machinery)性能(xìng néng)供應(ying);
C、按水壓試驗供應(ying)。GB9948無(wu)(wu)縫(feng)鋼(gang)管(guan)主要(yao)用(yong)(yong)來生產氣動或液壓 元件的產品，如氣缸或油缸，都(dou)是用(yong)(yong)無(wu)(wu)縫(feng)管(guan)。精密無(wu)(wu)縫(feng)鋼(gang)管(guan)的化學成分有(you)碳C、硅Si、錳Mn、硫S、磷P、鉻Cr。GB5310無(wu)(wu)縫(feng)鋼(gang)管(guan)按照用(yong)(yong)途分為結構用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan);輸送用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan);鍋爐用(yong)(yong)無(wu)(wu)縫(feng)鋼(gang)管(guan);鍋爐用(yong)(yong)高壓無(wu)(wu)縫(feng)鋼(gang)管(guan).無(wu)(wu)縫(feng)鋼(gang)管(guan)按照斷(duan)面形(xing)(xing)狀(zhuang)，無(wu)(wu)縫(feng)鋼(gang)管(guan)分圓形(xing)(xing)和異形(xing)(xing)兩種(zhong)，異形(xing)(xing)管(guan)有(you)方形(xing)(xing)、橢圓形(xing)(xing)、三(san)角形(xing)(xing)、六角形(xing)(xing)、瓜子形(xing)(xing)、星形(xing)(xing)、 帶翅管(guan)多種(zhong)復雜(za)形(xing)(xing)狀(zhuang)。按
A、b類供應的鋼(gang)管(guan)，如用(yong)(yong)(yong)(yong)(yong)(yong)于承受液體(ti)壓(ya)力(pressure)，也要進行水壓(ya)(特指(zhi):壓(ya)強)試(shi)驗。3、專門用(yong)(yong)(yong)(yong)(yong)(yong)途(tu)的無縫(feng)管(guan)有鍋爐(Boilers)用(yong)(yong)(yong)(yong)(yong)(yong)無縫(feng)管(guan)、化(hua)工(gong)電力用(yong)(yong)(yong)(yong)(yong)(yong)，地質用(yong)(yong)(yong)(yong)(yong)(yong)無縫(feng)鋼(gang)管(guan)及石(shi)油(petroleum)用(yong)(yong)(yong)(yong)(yong)(yong)無縫(feng)管(guan)等多種。 無縫(feng)鋼(gang)管(guan)具有中空(zhōng kōng)截(jie)面，大量(liang)(liang)用(yong)(yong)(yong)(yong)(yong)(yong)作(zuo)輸送流體(ti)的管(guan)道(dao)(Conduit)，如輸送石(shi)油、天然(ran)(natural)氣、煤氣(Coal Gas)、水及某些固體(ti)物料(liao)的管(guan)道(dao)等。鋼(gang)管(guan)與圓鋼(gang)等實心鋼(gang)材相比，在抗彎(wan)抗扭強度(strength)相同時，重量(liang)(liang)較輕，是一種經濟(Economy)截(jie)面鋼(gang)材。 廣(guang)泛(extensive)用(yong)(yong)(yong)(yong)(yong)(yong)于制(zhi)造(zao)(zhì zào)結構(Structure)件(jian)和機械(machinery)零件(jian)，如石(shi)油鉆桿、汽車(auto)傳動軸(zhou)(傳動軸(zhou)組(zu)成(cheng):軸(zhou)管(guan)、伸(shen)縮(suo)套和萬向節(jie)(jie))、自行車架(jia)以及建(jian)筑(Architecture)施工(gong)中用(yong)(yong)(yong)(yong)(yong)(yong)的鋼(gang)腳手架(jia)等用(yong)(yong)(yong)(yong)(yong)(yong)鋼(gang)管(guan)制(zhi)造(zao)環形零件(jian)，可提高材料(liao)(Material)利用(yong)(yong)(yong)(yong)(yong)(yong)率(availability)，簡化(hua)制(zhi)造(zao)工(gong)序(xu)，節(jie)(jie)約材料(liao)和加工(gong)(Processing)工(gong)時，已廣(guang)泛用(yong)(yong)(yong)(yong)(yong)(yong)鋼(gang)管(guan)來制(zhi)造(zao)。
