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恩施(shi)(shi)(shi)精(jing)密鋼(gang)(gang)管在(zai)(zai)熱(re)(re)(re)(re)(re)處(chu)理(li)(li)工(gong)(gong)藝中(zhong)(zhong)淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)工(gong)(gong)序造成的(de)廢品率往(wang)往(wang)較高，這主要是(shi)(shi)在(zai)(zai)淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)過(guo)程中(zhong)(zhong)，同時(shi)形(xing)(xing)成較大(da) 的(de)熱(re)(re)(re)(re)(re)應(ying)力與(yu)組織應(ying)力，此外，由于(yu)恩施(shi)(shi)(shi)精(jing)密鋼(gang)(gang)管內(nei)在(zai)(zai)的(de)冶金(jin)缺(que)陷、選材不當，錯料、設(she)計(ji)上的(de)結構工(gong)(gong)藝 性差(cha)(cha)、冷、熱(re)(re)(re)(re)(re)加(jia)(jia)(jia)工(gong)(gong)過(guo)程中(zhong)(zhong)形(xing)(xing)成的(de)缺(que)陷等(deng)因素(su)，均(jun)容易(yi)在(zai)(zai)淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)、回火(huo)(huo)(huo)(huo)(huo)工(gong)(gong)藝中(zhong)(zhong)暴露出來，因此對(dui)(dui)零部件(jian)(jian)(jian)(jian)(jian) 淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)、回火(huo)(huo)(huo)(huo)(huo)后(hou)的(de)缺(que)陷必須進行系(xi)統的(de)分析與(yu)調查。 淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)變(bian)(bian)形(xing)(xing)與(yu)淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)裂(lie)紋 在(zai)(zai)實際生(sheng)產中(zhong)(zhong)，應(ying)該根 據淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)變(bian)(bian)形(xing)(xing)與(yu)淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)裂(lie)紋的(de)形(xing)(xing)成原因采(cai)取有(you)效的(de)措(cuo)施(shi)(shi)(shi)。恩施(shi)(shi)(shi)精(jing)密管熱(re)(re)(re)(re)(re)處(chu)理(li)(li)盡管做到均(jun)勻(yun)(yun)(yun)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)及(ji)(ji)正 確加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)：工(gong)(gong)件(jian)(jian)(jian)(jian)(jian)形(xing)(xing)狀復(fu)雜或(huo)(huo)(huo)截面尺寸相差(cha)(cha)懸殊時(shi)，常(chang)因加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)不均(jun)勻(yun)(yun)(yun)而變(bian)(bian)形(xing)(xing)。為此，工(gong)(gong)件(jian)(jian)(jian)(jian)(jian)在(zai)(zai)裝爐前，對(dui)(dui) 不許淬(cui)(cui)(cui)硬的(de)孔及(ji)(ji)截面突變(bian)(bian)處(chu)，應(ying)采(cai)用石棉繩堵塞或(huo)(huo)(huo)綁扎等(deng)辦法，以(yi)改善其受熱(re)(re)(re)(re)(re)條件(jian)(jian)(jian)(jian)(jian)，對(dui)(dui)一些薄壁圓 環(huan)等(deng)易(yi)變(bian)(bian)形(xing)(xing)零件(jian)(jian)(jian)(jian)(jian)，可(ke)設(she)計(ji)特定淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)夾具，。這些措(cuo)施(shi)(shi)(shi)既有(you)利于(yu)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)均(jun)勻(yun)(yun)(yun)，又有(you)利于(yu)冷卻均(jun)勻(yun)(yun)(yun)。工(gong)(gong)件(jian)(jian)(jian)(jian)(jian) 在(zai)(zai)爐內(nei)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)時(shi)，應(ying)均(jun)勻(yun)(yun)(yun)放(fang)置，防止單面受熱(re)(re)(re)(re)(re)，應(ying)放(fang)平，避免工(gong)(gong)件(jian)(jian)(jian)(jian)(jian)在(zai)(zai)高溫(wen)塑(su)形(xing)(xing)狀態因自重而變(bian)(bian)形(xing)(xing)。對(dui)(dui) 細長零件(jian)(jian)(jian)(jian)(jian)及(ji)(ji)袖類零件(jian)(jian)(jian)(jian)(jian)盡量采(cai)用井式爐或(huo)(huo)(huo)鹽爐垂(chui)直懸掛(gua)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)。限(xian)制或(huo)(huo)(huo)降低加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)速(su)度(du)，可(ke)減(jian)少工(gong)(gong)件(jian)(jian)(jian)(jian)(jian)截面 溫(wen)差(cha)(cha)，使加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)均(jun)勻(yun)(yun)(yun)。因此對(dui)(dui)大(da)型鍛(duan)模、高速(su)鋼(gang)(gang)及(ji)(ji)高合金(jin)鋼(gang)(gang)工(gong)(gong)件(jian)(jian)(jian)(jian)(jian)，以(yi)及(ji)(ji)形(xing)(xing)狀復(fu)雜、厚薄不勻(yun)(yun)(yun)、要求變(bian)(bian) 形(xing)(xing)小(xiao)的(de)零件(jian)(jian)(jian)(jian)(jian)，一般都采(cai)用預(yu)熱(re)(re)(re)(re)(re)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)或(huo)(huo)(huo)限(xian)制加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)速(su)度(du)的(de)措(cuo)施(shi)(shi)(shi)。合理(li)(li)選擇淬(cui)(cui)(cui)火(huo)(huo)(huo)(huo)(huo)加(jia)(jia)(jia)熱(re)(re)(re)(re)(re)溫(wen)度(du)，也是(shi)(shi)減(jian)少或(huo)(huo)(huo)防 止變(bian)(bian)形(xing)(xing)、開(kai)裂(lie)的(de)關鍵。