1. 電凈液成分(fen)見(jian)表4-42.


表 42.jpg


2. 電凈液的性質(zhi)和用途(tu)


 電(dian)凈液(ye)都是堿性溶液(ye),pH為11~13.溶液(ye)呈(cheng)無色(se)透明,手(shou)摸有(you)滑感(gan),-10℃不結冰。


 電凈液具有較強的去油(you)作用,同時具有輕度的除氧化膜作用。


3. 使用(yong)方法


  用鍍(du)(du)筆(bi)蘸上(shang)(shang)電凈液,大型(xing)圓柱形工件(jian)夾在(zai)(zai)機床車(che)頭上(shang)(shang)旋(xuan)轉,鍍(du)(du)筆(bi)固定在(zai)(zai)刀架(jia)上(shang)(shang)不動,將鍍(du)(du)筆(bi)和工件(jian)接(jie)觸,并保持一定的相對運動速率,如果是平(ping)(ping)面(mian)工件(jian),則工件(jian)固定,鍍(du)(du)筆(bi)在(zai)(zai)工件(jian)平(ping)(ping)面(mian)上(shang)(shang)接(jie)觸,用手工移動保持相對運動速率。在(zai)(zai)通(tong)電的情況下在(zai)(zai)工件(jian)表面(mian)涂抹,達(da)到去油的目(mu)的。


  工(gong)(gong)件(jian)與鍍(du)筆(bi)之間的通(tong)電(dian)有(you)兩種方(fang)式:一(yi)種稱(cheng)為正(zheng)極(ji)性(xing)電(dian)凈,工(gong)(gong)件(jian)接(jie)負極(ji),鍍(du)筆(bi)接(jie)正(zheng)極(ji),去(qu)(qu)油效(xiao)(xiao)果快捷。通(tong)電(dian)時工(gong)(gong)件(jian)表(biao)面產(chan)生大量(liang)的氫氣,故工(gong)(gong)件(jian)有(you)滲氫現象(xiang);另一(yi)種稱(cheng)為反(fan)極(ji)性(xing)電(dian)凈,工(gong)(gong)件(jian)接(jie)正(zheng)極(ji),鍍(du)筆(bi)接(jie)負極(ji),通(tong)電(dian)時工(gong)(gong)件(jian)表(biao)面產(chan)生氧氣,其(qi)去(qu)(qu)油效(xiao)(xiao)果中等,作(zuo)用(yong)溫和,沒有(you)滲氫現象(xiang)。在(zai)實際工(gong)(gong)作(zuo)中,往往是采用(yong)高檔電(dian)壓(10~18V),先正(zheng)極(ji)性(xing)電(dian)凈后(hou)反(fan)極(ji)性(xing)電(dian)凈聯(lian)合應用(yong),效(xiao)(xiao)果最(zui)佳。


4. 電(dian)凈工藝(yi)條(tiao)件


 電壓10~18V,一(yi)般取12V;時(shi)間30~90s;電凈液(ye)溫(wen)度 15~50℃。


 電凈(jing)后(hou)立(li)(li)即(ji)用(yong)水沖洗干凈(jing),表面(mian)水膜分布(bu)均(jun)勻,金(jin)屬表面(mian)呈現均(jun)勻的潔凈(jing)狀態,立(li)(li)即(ji)進行下道(dao)工序,不可使表面(mian)形成干斑。