鋼管(guan)熱(re)處理可(ke)以分為(wei)兩類,即為(wei)了(le)滿足產品使用性能要求的(de)(de)最終(zhong)熱(re)處理和鋼管(guan)制造過(guo)程中的(de)(de)工(gong)序間的(de)(de)熱(re)處理。
同其他(ta)產(chan)品(pin)一樣,根據產(chan)品(pin)標準的(de)(de)技(ji)術條件要(yao)求,鋼管(guan)(guan)(guan)(guan)常(chang)用(yong)(yong)的(de)(de)熱處(chu)理工(gong)(gong)藝(yi)主要(yao)有(you)淬(cui)火(huo)(huo)(huo)、回(hui)(hui)(hui)火(huo)(huo)(huo)、正(zheng)火(huo)(huo)(huo)及退(tui)火(huo)(huo)(huo)等(deng)。例如;石油(you)專用(yong)(yong)管(guan)(guan)(guan)(guan)中(zhong)的(de)(de)套管(guan)(guan)(guan)(guan)、油(you)管(guan)(guan)(guan)(guan)、鉆桿、管(guan)(guan)(guan)(guan)線管(guan)(guan)(guan)(guan)等(deng),根據鋼級的(de)(de)高(gao)低則相應采用(yong)(yong)正(zheng)火(huo)(huo)(huo)、正(zheng)火(huo)(huo)(huo)加(jia)(jia)(jia)(jia)(jia)回(hui)(hui)(hui)火(huo)(huo)(huo)、淬(cui)火(huo)(huo)(huo)加(jia)(jia)(jia)(jia)(jia)回(hui)(hui)(hui)火(huo)(huo)(huo)(調質(zhi))的(de)(de)工(gong)(gong)藝(yi);高(gao)壓鍋爐(lu)管(guan)(guan)(guan)(guan)、高(gao)壓化肥管(guan)(guan)(guan)(guan)通(tong)常(chang)采用(yong)(yong)正(zheng)火(huo)(huo)(huo)、正(zheng)火(huo)(huo)(huo)加(jia)(jia)(jia)(jia)(jia)回(hui)(hui)(hui)火(huo)(huo)(huo)、淬(cui)火(huo)(huo)(huo)加(jia)(jia)(jia)(jia)(jia)回(hui)(hui)(hui)火(huo)(huo)(huo)(厚壁管(guan)(guan)(guan)(guan))及奧(ao)氏體不(bu)銹鋼管(guan)(guan)(guan)(guan)的(de)(de)固溶處(chu)理;軸承用(yong)(yong)鋼管(guan)(guan)(guan)(guan)的(de)(de)球(qiu)化退(tui)火(huo)(huo)(huo)等(deng)。工(gong)(gong)序間的(de)(de)熱處(chu)理用(yong)(yong)于(yu)(yu)冷(leng)軋、冷(leng)拔鋼管(guan)(guan)(guan)(guan)的(de)(de)生產(chan)過程中(zhong),通(tong)常(chang)采用(yong)(yong)再結晶退(tui)火(huo)(huo)(huo)、軟(ruan)化退(tui)火(huo)(huo)(huo),目的(de)(de)在于(yu)(yu)消除(chu)冷(leng)加(jia)(jia)(jia)(jia)(jia)工(gong)(gong)硬化效應,降低硬度、提高(gao)塑性(xing)以利于(yu)(yu)進一步冷(leng)變形工(gong)(gong)序得以實施(shi)。
應在(zai)了解了鋼(gang)管執行的標準或者用(yong)戶技術要求的前提下(xia),再來確定(ding)熱處理工(gong)(gong)(gong)藝(yi)(yi),即正火(huo)、淬(cui)火(huo)、回(hui)火(huo)及(ji)退(tui)火(huo)等(deng)。其(qi)后再根(gen)據鋼(gang)管所使(shi)用(yong)的鋼(gang)種(zhong)確定(ding)工(gong)(gong)(gong)藝(yi)(yi)參(can)數(shu):如工(gong)(gong)(gong)藝(yi)(yi)溫度、保溫時間(jian)和冷卻方式等(deng)。工(gong)(gong)(gong)藝(yi)(yi)參(can)數(shu)應依(yi)據鋼(gang)種(zhong)的成分、物理性(xing)能、工(gong)(gong)(gong)藝(yi)(yi)性(xing)能及(ji)所使(shi)用(yong)的設(she)備性(xing)能等(deng)多種(zhong)因(yin)素來確定(ding)。對于一(yi)種(zhong)新產(chan)品,應遵循實驗(yan)室試驗(yan)-生產(chan)試驗(yan)-試生產(chan)-正常生產(chan)這樣一(yi)種(zhong)科學程(cheng)序。
鋼管(guan)熱(re)處理的(de)目的(de)體現在以下個方面(mian):
1. 為(wei)使鋼(gang)(gang)管組織均勻化(hua) 通(tong)過熱(re)處理(li)可以(yi)消(xiao)除原來鋼(gang)(gang)管生產中產生的組織性(xing)能不均,達到所要求(qiu)的均勻組織和物理(li)性(xing)能;
2. 消(xiao)除生產(chan)中留下的缺(que)陷 如冷(leng)拔(ba)鋼管(guan)加工后生產(chan)的硬化使強度提高1.3~1.6倍(bei),延伸率相應降低了(le)30%~35%,繼續冷(leng)加工就會拔(ba)斷,因此需要中間(jian)退火以(yi)消(xiao)除內應力;當熱軋無縫(feng)鋼管(guan)中殘余應力較大,影響其抗腐蝕性能、抗擊毀性能時也需要進行(xing)消(xiao)除殘余應力熱處理;
3. 進一步提高鋼管(guan)的(de)質量 滿足不同用戶要(yao)求,但為了提高產品質量,適(shi)應(ying)高鋼級用途,延長使用壽命,增加產品競(jing)爭力,也(ye)要(yao)進行熱處(chu)理;
4. 簡(jian)化(hua)工藝 同(tong)(tong)一(yi)種原(yuan)料(liao)和(he)加工方法,在控制不同(tong)(tong)的(de)熱處理(li)條件下,可以生產出具有多種不同(tong)(tong)性能的(de)產品,從而可使原(yuan)料(liao)單(dan)一(yi)化(hua)。