精拔無縫鋼管一米起售

　　精拔無縫鋼管主要特點是無焊接縫，可承受較大的壓力。產品可以是很粗糙的鑄態或冷撥件。精拔無縫鋼管是近幾(ji)年出現(xian)的產(chan)品，主要是內孔、外(wai)壁(bi)尺寸有嚴格(ge)的公差(cha)及(ji)粗(cu)糙(cao)度。

　　精(jing)(jing)拔無(wu)縫(feng)鋼管(guan)(guan)(guan)是一種通過(guo)精(jing)(jing)拔或(huo)冷(leng)軋處(chu)理后的一種高(gao)精(jing)(jing)密的鋼管(guan)(guan)(guan)材(cai)料(liao)。由于精(jing)(jing)拔無(wu)縫(feng)鋼管(guan)(guan)(guan)內外(wai)壁無(wu)氧化層、承受(shou)高(gao)壓(ya)(ya)無(wu)泄(xie)漏、高(gao)精(jing)(jing)度、高(gao)光潔度、冷(leng)彎不變形、擴口、壓(ya)(ya)扁無(wu)裂縫(feng)等有點，主(zhu)要用(yong)來生產氣動或(huo)液壓(ya)(ya) 元件(jian)的產品，如氣缸或(huo)油缸，可(ke)以是無(wu)縫(feng)管(guan)(guan)(guan)，也有焊接(jie)管(guan)(guan)(guan)。

　　特點

　　1.外徑更小。

　　2.精度高可做小批量生

　　3.冷拔(ba)成品(pin)精度高(gao)，表面(mian)質量(liang)好。

　　4.精(jing)拔無縫鋼管橫面(mian)積更(geng)復雜。

　　5.鋼(gang)管性能更(geng)優越，金(jin)屬(shu)比較密(mi)。

　　精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing) 合金(jin)鋼(gang)(gang)(gang)淬(cui)火(huo)得到馬氏體(ti)(ti)組織后，在(zai)(zai)(zai)250～400℃溫(wen)(wen)度范(fan)圍(wei)回(hui)火(huo)使鋼(gang)(gang)(gang)脆(cui)(cui)(cui)化(hua)(hua)，其韌性(xing)(xing)一脆(cui)(cui)(cui)性(xing)(xing)轉化(hua)(hua)溫(wen)(wen)度明顯升高。已(yi)脆(cui)(cui)(cui)化(hua)(hua)的(de)精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管不能再用(yong)低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)加熱(re)的(de)方(fang)法消除(chu)，故又(you)稱為%26ldquo;不可逆回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing)%26rdquo;。精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管主(zhu)要發(fa)生(sheng)(sheng)在(zai)(zai)(zai)合金(jin)結構(gou)鋼(gang)(gang)(gang)和(he)低(di)(di)(di)(di)合金(jin)超高強度精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管等(deng)鋼(gang)(gang)(gang)種(zhong)。已(yi)脆(cui)(cui)(cui)化(hua)(hua)精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管的(de)斷(duan)口是沿晶(jing)(jing)(jing)(jing)斷(duan)口或是沿晶(jing)(jing)(jing)(jing)和(he)準解理混合斷(duan)口。產(chan)生(sheng)(sheng)低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing)的(de)原(yuan)因(yin)，普(pu)遍認為：(1)與滲碳體(ti)(ti)在(zai)(zai)(zai)低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)時以薄(bo)片狀(zhuang)在(zai)(zai)(zai)原(yuan)奧(ao)(ao)氏體(ti)(ti)晶(jing)(jing)(jing)(jing)界(jie)(jie)析出，造成(cheng)(cheng)晶(jing)(jing)(jing)(jing)界(jie)(jie)脆(cui)(cui)(cui)化(hua)(hua)密切相關。(2)雜質元(yuan)素磷等(deng)在(zai)(zai)(zai)原(yuan)奧(ao)(ao)氏體(ti)(ti)晶(jing)(jing)(jing)(jing)界(jie)(jie)偏(pian)聚也是造成(cheng)(cheng)低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing)原(yuan)因(yin)之一。含磷低(di)(di)(di)(di)于0.005%的(de)高純度精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管并(bing)不產(chan)生(sheng)(sheng)低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing)。磷在(zai)(zai)(zai)火(huo)加熱(re)時發(fa)生(sheng)(sheng)奧(ao)(ao)氏體(ti)(ti)晶(jing)(jing)(jing)(jing)界(jie)(jie)偏(pian)聚，淬(cui)火(huo)后保(bao)留下來。磷在(zai)(zai)(zai)原(yuan)奧(ao)(ao)氏體(ti)(ti)晶(jing)(jing)(jing)(jing)界(jie)(jie)偏(pian)聚和(he)滲碳體(ti)(ti)回(hui)火(huo)時在(zai)(zai)(zai)原(yuan)奧(ao)(ao)氏體(ti)(ti)晶(jing)(jing)(jing)(jing)界(jie)(jie)析出，這兩個因(yin)素造成(cheng)(cheng)沿晶(jing)(jing)(jing)(jing)脆(cui)(cui)(cui)斷(duan)，促成(cheng)(cheng)了(le)精(jing)拔(ba)無(wu)(wu)縫(feng)鋼(gang)(gang)(gang)管低(di)(di)(di)(di)溫(wen)(wen)回(hui)火(huo)脆(cui)(cui)(cui)性(xing)(xing)的(de)發(fa)生(sheng)(sheng)。

　　精(jing)拔無縫(feng)鋼(gang)管中合金元素(su)對低溫(wen)回(hui)火(huo)(huo)脆(cui)性產生(sheng)較大的(de)(de)影(ying)(ying)響。鉻和錳促進(jin)雜質元素(su)磷等在奧氏(shi)體晶界偏聚(ju)，從(cong)而促進(jin)低溫(wen)回(hui)火(huo)(huo)脆(cui)性，鎢和釩(fan)基本(ben)上沒有影(ying)(ying)響，鉬降低低溫(wen)回(hui)火(huo)(huo)精(jing)拔無縫(feng)鋼(gang)管的(de)(de)韌性一脆(cui)性轉(zhuan)化溫(wen)度，但尚不(bu)足(zu)以抑制低溫(wen)回(hui)火(huo)(huo)脆(cui)性。硅能推遲回(hui)火(huo)(huo)時滲碳(tan)體析出，提高其生(sheng)成溫(wen)度，故可提高精(jing)拔無縫(feng)鋼(gang)管低溫(wen)回(hui)火(huo)(huo)脆(cui)性發生(sheng)的(de)(de)溫(wen)度。