快(kuai)走絲(si)線切割斷絲(si)原因(yin)主要有(you)以下(xia)四種：

1、鉬絲(si)(si)鉬絲(si)(si)的松緊程度

如(ru)果鉬(mu)絲(si)(si)(si)(si)(si)(si)安(an)裝(zhuang)太(tai)松，則鉬(mu)絲(si)(si)(si)(si)(si)(si)抖動(dong)厲害(hai)，不(bu)僅會(hui)造成斷絲(si)(si)(si)(si)(si)(si)，而(er)(er)且由于鉬(mu)絲(si)(si)(si)(si)(si)(si)的(de)(de)抖動(dong)直接(jie)影響工(gong)件表面粗糙度(du)。但鉬(mu)絲(si)(si)(si)(si)(si)(si)也不(bu)能(neng)安(an)裝(zhuang)得(de)太(tai)緊(jin)(jin)(jin)(jin)，太(tai)緊(jin)(jin)(jin)(jin)內應(ying)(ying)力增大，也會(hui)造成斷絲(si)(si)(si)(si)(si)(si)，因(yin)此鉬(mu)絲(si)(si)(si)(si)(si)(si)在(zai)(zai)切割過程(cheng)中，其(qi)松緊(jin)(jin)(jin)(jin)程(cheng)度(du)要(yao)適當(dang)，新安(an)裝(zhuang)的(de)(de)鉬(mu)絲(si)(si)(si)(si)(si)(si)，要(yao)先緊(jin)(jin)(jin)(jin)絲(si)(si)(si)(si)(si)(si)再加工(gong)，緊(jin)(jin)(jin)(jin)絲(si)(si)(si)(si)(si)(si)時(shi)(shi)(shi)用力不(bu)要(yao)太(tai)大。鉬(mu)絲(si)(si)(si)(si)(si)(si)在(zai)(zai)加工(gong)一(yi)(yi)段時(shi)(shi)(shi)間(jian)后，由于自身的(de)(de)拉伸而(er)(er)變(bian)松。當(dang)伸長量較大時(shi)(shi)(shi)，會(hui)加劇鉬(mu)絲(si)(si)(si)(si)(si)(si)振動(dong)或出(chu)現鉬(mu)絲(si)(si)(si)(si)(si)(si)在(zai)(zai)貯絲(si)(si)(si)(si)(si)(si)筒上重疊。使走(zou)絲(si)(si)(si)(si)(si)(si)不(bu)穩(wen)而(er)(er)引起斷絲(si)(si)(si)(si)(si)(si)。應(ying)(ying)經(jing)常檢(jian)查(cha)鉬(mu)絲(si)(si)(si)(si)(si)(si)的(de)(de)松緊(jin)(jin)(jin)(jin)程(cheng)度(du)，如(ru)果存在(zai)(zai)松弛(chi)現象，要(yao)及時(shi)(shi)(shi)拉緊(jin)(jin)(jin)(jin)。鉬(mu)絲(si)(si)(si)(si)(si)(si)安(an)裝(zhuang)：鉬(mu)絲(si)(si)(si)(si)(si)(si)要(yao)按規定的(de)(de)走(zou)向(xiang)繞在(zai)(zai)貯絲(si)(si)(si)(si)(si)(si)筒上，同(tong)時(shi)(shi)(shi)固定兩(liang)端(duan)。繞絲(si)(si)(si)(si)(si)(si)時(shi)(shi)(shi)，一(yi)(yi)般貯絲(si)(si)(si)(si)(si)(si)筒兩(liang)端(duan)各(ge)留10mm，中間(jian)繞滿不(bu)重疊，寬度(du)不(bu)少(shao)于貯絲(si)(si)(si)(si)(si)(si)筒長度(du)的(de)(de)一(yi)(yi)半，以免(mian)電機(ji)換向(xiang)頻(pin)繁而(er)(er)使機(ji)件加速(su)損(sun)壞，也防止鉬(mu)絲(si)(si)(si)(si)(si)(si)頻(pin)繁參與(yu)切割而(er)(er)斷絲(si)(si)(si)(si)(si)(si)。機(ji)床上鉬(mu)絲(si)(si)(si)(si)(si)(si)引出(chu)處有擋絲(si)(si)(si)(si)(si)(si)棒，擋絲(si)(si)(si)(si)(si)(si)棒是由兩(liang)根紅寶石制成的(de)(de)導向(xiang)立柱(zhu)，擋絲(si)(si)(si)(si)(si)(si)棒不(bu)像(xiang)導輪那(nei)樣作滾動(dong)運動(dong)，他們直接(jie)與(yu)鉬(mu)絲(si)(si)(si)(si)(si)(si)接(jie)觸，作滑動(dong)摩擦。因(yin)此磨損(sun)很快，使用不(bu)久(jiu)柱(zhu)體(ti)與(yu)鉬(mu)絲(si)(si)(si)(si)(si)(si)接(jie)觸的(de)(de)地方(fang)就會(hui)形成深溝，必須及時(shi)(shi)(shi)檢(jian)查(cha)并進行翻轉和(he)更換，否則會(hui)出(chu)現疊絲(si)(si)(si)(si)(si)(si)斷絲(si)(si)(si)(si)(si)(si)。

2、運絲機構

中(zhong)走絲(si)(si)(si)(si)線(xian)(xian)切割(ge)機(ji)(ji)的(de)運(yun)(yun)(yun)絲(si)(si)(si)(si)機(ji)(ji)構(gou)(gou)主(zhu)要(yao)是(shi)由貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)、線(xian)(xian)架(jia)和(he)導(dao)(dao)(dao)輪(lun)(lun)組成(cheng)。當運(yun)(yun)(yun)絲(si)(si)(si)(si)機(ji)(ji)構(gou)(gou)的(de)精度下降時(shi)(shi)(shi)（主(zhu)要(yao)是(shi)傳動(dong)(dong)(dong)(dong)軸(zhou)承(cheng)），會(hui)引起貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)的(de)徑(jing)向(xiang)(xiang)跳動(dong)(dong)(dong)(dong)和(he)軸(zhou)向(xiang)(xiang)竄(cuan)動(dong)(dong)(dong)(dong)。貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)的(de)徑(jing)向(xiang)(xiang)跳動(dong)(dong)(dong)(dong)會(hui)使(shi)電(dian)極絲(si)(si)(si)(si)的(de)張力減小，造成(cheng)絲(si)(si)(si)(si)松(song)，嚴重時(shi)(shi)(shi)會(hui)使(shi)鉬(mu)絲(si)(si)(si)(si)從導(dao)(dao)(dao)輪(lun)(lun)槽中(zhong)脫出(chu)拉(la)斷(duan)(duan)。貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)的(de)軸(zhou)向(xiang)(xiang)竄(cuan)動(dong)(dong)(dong)(dong)會(hui)使(shi)排絲(si)(si)(si)(si)不(bu)勻(yun)，產生疊絲(si)(si)(si)(si)現(xian)象。貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)的(de)軸(zhou)和(he)軸(zhou)承(cheng)等零件(jian)(jian)(jian)常因(yin)(yin)磨損而(er)產生間(jian)隙，也(ye)容易引起絲(si)(si)(si)(si)抖動(dong)(dong)(dong)(dong)而(er)斷(duan)(duan)絲(si)(si)(si)(si)，因(yin)(yin)此必(bi)須及(ji)時(shi)(shi)(shi)更(geng)換磨損的(de)軸(zhou)和(he)軸(zhou)承(cheng)等零件(jian)(jian)(jian)。貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)換向(xiang)(xiang)時(shi)(shi)(shi)，如沒有切斷(duan)(duan)高頻電(dian)源，快走絲(si)(si)(si)(si)線(xian)(xian)切割(ge)會(hui)導(dao)(dao)(dao)致鉬(mu)絲(si)(si)(si)(si)在(zai)短時(shi)(shi)(shi)間(jian)內溫度過高而(er)燒斷(duan)(duan)鉬(mu)絲(si)(si)(si)(si)，因(yin)(yin)此必(bi)須檢(jian)(jian)查貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)后端的(de)行程開關是(shi)否失(shi)靈(ling)。要(yao)保持貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)、導(dao)(dao)(dao)輪(lun)(lun)轉動(dong)(dong)(dong)(dong)靈(ling)活，否則在(zai)往返運(yun)(yun)(yun)動(dong)(dong)(dong)(dong)時(shi)(shi)(shi)會(hui)引起運(yun)(yun)(yun)絲(si)(si)(si)(si)系統振動(dong)(dong)(dong)(dong)而(er)斷(duan)(duan)絲(si)(si)(si)(si)。繞(rao)絲(si)(si)(si)(si)后空載走絲(si)(si)(si)(si)檢(jian)(jian)驗(yan)鉬(mu)絲(si)(si)(si)(si)是(shi)否抖動(dong)(dong)(dong)(dong)，若發生抖動(dong)(dong)(dong)(dong)要(yao)分析原(yuan)因(yin)(yin)。貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)后端的(de)限(xian)位(wei)擋(dang)塊(kuai)必(bi)須調整好(hao)，避免貯(zhu)絲(si)(si)(si)(si)筒(tong)(tong)(tong)(tong)(tong)沖出(chu)限(xian)位(wei)行程而(er)斷(duan)(duan)絲(si)(si)(si)(si)。擋(dang)絲(si)(si)(si)(si)裝置(zhi)中(zhong)擋(dang)塊(kuai)與快速運(yun)(yun)(yun)動(dong)(dong)(dong)(dong)的(de)鉬(mu)絲(si)(si)(si)(si)接(jie)觸、摩擦，易產生溝槽并造成(cheng)夾絲(si)(si)(si)(si)拉(la)斷(duan)(duan)，因(yin)(yin)此也(ye)需及(ji)時(shi)(shi)(shi)更(geng)換。導(dao)(dao)(dao)輪(lun)(lun)軸(zhou)承(cheng)的(de)磨損將直接(jie)影響導(dao)(dao)(dao)絲(si)(si)(si)(si)精度，此外(wai)，當導(dao)(dao)(dao)輪(lun)(lun)的(de)v型槽、寶(bao)石限(xian)位(wei)塊(kuai)、導(dao)(dao)(dao)電(dian)塊(kuai)磨損后產生的(de)溝槽，也(ye)會(hui)使(shi)電(dian)極絲(si)(si)(si)(si)的(de)摩擦力過大，易將鉬(mu)絲(si)(si)(si)(si)拉(la)斷(duan)(duan)。這(zhe)種現(xian)象一般(ban)發生在(zai)機(ji)(ji)床(chuang)使(shi)用時(shi)(shi)(shi)間(jian)較(jiao)長、加工工件(jian)(jian)(jian)較(jiao)厚、運(yun)(yun)(yun)絲(si)(si)(si)(si)機(ji)(ji)構(gou)(gou)不(bu)易清理的(de)情(qing)況下。因(yin)(yin)此在(zai)機(ji)(ji)床(chuang)使(shi)用中(zhong)應定(ding)期檢(jian)(jian)查運(yun)(yun)(yun)絲(si)(si)(si)(si)機(ji)(ji)構(gou)(gou)的(de)精度，及(ji)時(shi)(shi)(shi)更(geng)換易磨損件(jian)(jian)(jian)。

3、工件

工(gong)件材料(liao)：對不經鍛打、不淬火材料(liao)，在(zai)(zai)線切割(ge)加工(gong)前zui好(hao)采用(yong)低溫(wen)回火消(xiao)除內應力，因為如果工(gong)件的內應力沒有得到消(xiao)除，在(zai)(zai)切割(ge)時(shi)(shi)，有的工(gong)件會開裂，把鉬(mu)絲(si)碰斷(duan)；有的會使間隙變形，把鉬(mu)絲(si)夾斷(duan)或彈(dan)斷(duan)。如淬火后t8鋼在(zai)(zai)線切割(ge)加工(gong)中及(ji)易(yi)引起斷(duan)絲(si)盡量少用(yong)。切割(ge)厚鋁材料(liao)時(shi)(shi)，由于排屑困(kun)難，導電(dian)塊磨(mo)損較大，注(zhu)意及(ji)時(shi)(shi)更換。

工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)裝夾(jia)：雖然線切割加(jia)工(gong)(gong)(gong)(gong)過(guo)程中工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)受(shou)力(li)極小，但仍需牢(lao)固夾(jia)緊工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)，防(fang)止加(jia)工(gong)(gong)(gong)(gong)過(guo)程中因(yin)工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)位置變動造(zao)成斷(duan)(duan)絲(si)。同時要(yao)避免由于(yu)工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)的(de)自(zi)重和工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)材料的(de)彈性變形造(zao)成的(de)斷(duan)(duan)絲(si)。在加(jia)工(gong)(gong)(gong)(gong)厚(hou)重工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)時，可在加(jia)工(gong)(gong)(gong)(gong)快要(yao)結(jie)束時，用磁鐵(tie)吸住將要(yao)下落(luo)的(de)工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)，或者人工(gong)(gong)(gong)(gong)保護下落(luo)的(de)工(gong)(gong)(gong)(gong)件(jian)(jian)(jian)(jian)(jian)，使(shi)其平行緩(huan)慢(man)下落(luo)從而防(fang)止斷(duan)(duan)絲(si)。

4、電參數

電(dian)(dian)參數選擇不當也是引起斷(duan)(duan)絲(si)的(de)(de)一(yi)個重要原因(yin)，所以要根據工(gong)件厚度選擇合理的(de)(de)電(dian)(dian)參數，將脈(mo)沖間(jian)隔拉開一(yi)些(xie)，有利于熔化金屬微(wei)粒(li)的(de)(de)排出，同(tong)時(shi)峰值(zhi)電(dian)(dian)流(liu)和空載電(dian)(dian)壓不宜過高(gao)，否(fou)則使(shi)單(dan)個脈(mo)沖能量變大，切割速度加(jia)快，容易產(chan)生集中放電(dian)(dian)和拉弧，引起斷(duan)(duan)絲(si)。一(yi)般空載電(dian)(dian)壓為(wei)100v左右。在電(dian)(dian)火花(hua)加(jia)工(gong)中，電(dian)(dian)弧放電(dian)(dian)是造成負極腐蝕(shi)損壞的(de)(de)主要因(yin)素(su)，再加(jia)上間(jian)隙(xi)不合適，容易使(shi)某(mou)一(yi)脈(mo)沖形成電(dian)(dian)弧放電(dian)(dian)，只要電(dian)(dian)弧放電(dian)(dian)集中于某(mou)一(yi)段(duan)，就會引起斷(duan)(duan)絲(si)。

根據工件(jian)厚度選(xuan)擇合(he)適的放(fang)電(dian)(dian)間(jian)(jian)隙：放(fang)電(dian)(dian)間(jian)(jian)隙不(bu)能太小，否(fou)則容(rong)易產生短路(lu)，也不(bu)利(li)于冷卻和(he)電(dian)(dian)蝕物的排(pai)出；放(fang)電(dian)(dian)間(jian)(jian)隙過大(da)(da)，將影響表面(mian)粗糙度及加工速(su)度。快(kuai)走絲線切(qie)割當(dang)切(qie)割厚度較大(da)(da)的工件(jian)時，應盡(jin)量選(xuan)用(yong)大(da)(da)脈寬(kuan)電(dian)(dian)流，同時放(fang)電(dian)(dian)間(jian)(jian)隙也要大(da)(da)一點，長而(er)增強排(pai)屑效果，提高切(qie)割的穩定性。