環氧樹脂：點火線圈灌封料首選

車用汽(qi)油發動(dong)機(ji)(ji)氣(qi)缸內的燃料(liao)(liao)和(he)空氣(qi)混(hun)合(he)氣(qi)是(shi)(shi)靠(kao)高(gao)壓(ya)電火(huo)花來(lai)實(shi)現(xian)點(dian)燃的。點(dian)火(huo)線(xian)(xian)(xian)(xian)圈(quan)是(shi)(shi)形(xing)成(cheng)這種高(gao)壓(ya)電火(huo)花的高(gao)壓(ya)部(bu)件(jian)，產生(sheng)高(gao)電壓(ya)達30 kV以上(shang)，因此處(chu)理好(hao)點(dian)火(huo)線(xian)(xian)(xian)(xian)圈(quan)的絕(jue)緣強度是(shi)(shi)提高(gao)其產品質量、可靠(kao)性(xing)和(he)壽命的關鍵。解決線(xian)(xian)(xian)(xian)圈(quan)中空氣(qi)絕(jue)緣處(chu)理最好(hao)的方(fang)法(fa)是(shi)(shi)采用樹(shu)(shu)脂(zhi)真(zhen)空灌(guan)(guan)封(feng)(feng)工藝，所謂(wei)樹(shu)(shu)脂(zhi)真(zhen)空灌(guan)(guan)封(feng)(feng)工藝就是(shi)(shi)先將澆(jiao)(jiao)注用樹(shu)(shu)脂(zhi)灌(guan)(guan)封(feng)(feng)料(liao)(liao)進(jin)(jin)行(xing)真(zhen)空脫泡(pao)處(chu)理，再把經過預烘干燥(zao)處(chu)理、待封(feng)(feng)裝的點(dian)火(huo)線(xian)(xian)(xian)(xian)圈(quan)放在真(zhen)空澆(jiao)(jiao)注室中進(jin)(jin)行(xing)前期真(zhen)空干燥(zao)處(chu)理，使線(xian)(xian)(xian)(xian)圈(quan)與(yu)骨(gu)架、線(xian)(xian)(xian)(xian)包與(yu)外(wai)殼之間(jian)的氣(qi)體全部(bu)排出，然后在真(zhen)空條(tiao)(tiao)件(jian)下用完全脫過泡(pao)的已混(hun)合(he)好(hao)的灌(guan)(guan)封(feng)(feng)料(liao)(liao)進(jin)(jin)行(xing)封(feng)(feng)裝。哪么真(zhen)空灌(guan)(guan)封(feng)(feng)采用什么材料(liao)(liao)為(wei)(wei)好(hao)？專家(jia)日(ri)前介紹說(shuo)，從(cong)各方(fang)面進(jin)(jin)行(xing)考(kao)察，環氧樹(shu)(shu)脂(zhi)是(shi)(shi)首選。在選擇真(zhen)空灌(guan)(guan)封(feng)(feng)材料(liao)(liao)時，可根據使用環境(jing)提出樹(shu)(shu)脂(zhi)灌(guan)(guan)封(feng)(feng)料(liao)(liao)技術條(tiao)(tiao)件(jian)進(jin)(jin)行(xing)。目前應用于車用點(dian)火(huo)線(xian)(xian)(xian)(xian)圈(quan)的樹(shu)(shu)脂(zhi)灌(guan)(guan)封(feng)(feng)料(liao)(liao)主要有聚(ju)(ju)氨酯、有機(ji)(ji)硅(gui)和(he)環氧樹(shu)(shu)脂(zhi)3種，其中聚(ju)(ju)氨酯和(he)有機(ji)(ji)硅(gui)都為(wei)(wei)彈性(xing)體，從(cong)灌(guan)(guan)封(feng)(feng)條(tiao)(tiao)件(jian)、設備條(tiao)(tiao)件(jian)、絕(jue)緣強度、成(cheng)本及原料(liao)(liao)來(lai)源方(fang)面，環氧樹(shu)(shu)脂(zhi)最優。

　　專家(jia)表示，另外(wai)需要(yao)(yao)注意的(de)(de)(de)(de)(de)是：汽車點(dian)(dian)火線(xian)圈(quan)環(huan)氧樹(shu)(shu)脂(zhi)(zhi)灌(guan)(guan)封料(liao)的(de)(de)(de)(de)(de)技(ji)術(shu)要(yao)(yao)求固化(hua)物(wu)具有(you)(you)優良的(de)(de)(de)(de)(de)電氣性(xing)能，產(chan)品須具有(you)(you)優異的(de)(de)(de)(de)(de)耐高低溫沖擊(ji)性(xing)、耐久性(xing)和(he)不開(kai)裂(lie)性(xing)，具體(ti)地說就(jiu)是汽車點(dian)(dian)火線(xian)圈(quan)環(huan)氧樹(shu)(shu)脂(zhi)(zhi)灌(guan)(guan)封料(liao)的(de)(de)(de)(de)(de)技(ji)術(shu)要(yao)(yao)求為耐冷熱沖擊(ji)-40～120℃/h、400個(ge)循(xun)環(huan)、壽命(ming)試(shi)驗(yan)140℃環(huan)境(jing)≥1000h，國(guo)內這類產(chan)品主(zhu)要(yao)(yao)還是依靠國(guo)外(wai)進(jin)(jin)口，日本Somar公(gong)司、瑞士Ciba公(gong)司、美國(guo)Ther-moset plastics公(gong)司都有(you)(you)這方面的(de)(de)(de)(de)(de)產(chan)品。而(er)摩(mo)托(tuo)車點(dian)(dian)火線(xian)圈(quan)用(yong)(yong)環(huan)氧樹(shu)(shu)脂(zhi)(zhi)灌(guan)(guan)封料(liao)應能承受峰值電壓35kV，歷時1 min開(kai)路試(shi)驗(yan)而(er)無擊(ji)穿損傷(shang)和(he)表面放電現(xian)象，在-40℃和(he)80℃中各保(bao)持1h為1個(ge)循(xun)環(huan)，共5個(ge)循(xun)環(huan)的(de)(de)(de)(de)(de)溫度(du)變(bian)化(hua)試(shi)驗(yan)而(er)無損傷(shang)，強(qiang)化(hua)耐久壽命(ming)達240h以(yi)(yi)上(shang)(shang)，摩(mo)托(tuo)車用(yong)(yong)環(huan)氧樹(shu)(shu)脂(zhi)(zhi)灌(guan)(guan)封料(liao)主(zhu)要(yao)(yao)強(qiang)調耐壓性(xing)能。環(huan)氧樹(shu)(shu)脂(zhi)(zhi)灌(guan)(guan)封料(liao)的(de)(de)(de)(de)(de)外(wai)觀(guan)可以(yi)(yi)看(kan)出：汽車點(dian)(dian)火線(xian)圈(quan)所使用(yong)(yong)的(de)(de)(de)(de)(de)灌(guan)(guan)封料(liao)黏度(du)大，加(jia)(jia)熱到(dao)110℃以(yi)(yi)上(shang)(shang)黏度(du)才迅(xun)(xun)速(su)下(xia)降(jiang)，并且添加(jia)(jia)的(de)(de)(de)(de)(de)填(tian)料(liao)量(liang)較多；而(er)摩(mo)托(tuo)車點(dian)(dian)火線(xian)圈(quan)使用(yong)(yong)的(de)(de)(de)(de)(de)灌(guan)(guan)封料(liao)黏度(du)小些(xie)，加(jia)(jia)熱到(dao)60℃上(shang)(shang)黏度(du)就(jiu)迅(xun)(xun)速(su)下(xia)降(jiang)，填(tian)料(liao)量(liang)較少。用(yong)(yong)戶在進(jin)(jin)貨時可用(yong)(yong)一些(xie)簡便的(de)(de)(de)(de)(de)方法檢(jian)測樹(shu)(shu)脂(zhi)(zhi)的(de)(de)(de)(de)(de)可靠性(xing)：用(yong)(yong)一次性(xing)紙杯提取適量(liang)灌(guan)(guan)封料(liao)A組分，根據預定的(de)(de)(de)(de)(de)工作溫度(du)進(jin)(jin)行加(jia)(jia)熱保(bao)持8h以(yi)(yi)上(shang)(shang)，觀(guan)測棚旨料(liao)的(de)(de)(de)(de)(de)變(bian)化(hua)情況(kuang)。

　　汽(qi)車用(yong)(yong)灌(guan)(guan)封(feng)(feng)(feng)(feng)料(liao)(liao)，可(ke)加熱(re)130℃/8h:摩(mo)托車用(yong)(yong)灌(guan)(guan)封(feng)(feng)(feng)(feng)料(liao)(liao)，可(ke)加熱(re)80℃/8h。不(bu)出(chu)(chu)現(xian)大(da)量沉積物(wu)且物(wu)料(liao)(liao)流動性好的(de)為(wei)合格品(pin)(pin)，否則為(wei)不(bu)合格品(pin)(pin)。有條(tiao)(tiao)件也(ye)可(ke)制作(zuo)1 mm厚圓切片固化(hua)物(wu)，進(jin)(jin)行(xing)(xing)(xing)打(da)壓(ya)耐(nai)壓(ya)試驗(yan)，擊穿電(dian)壓(ya)小(xiao)(xiao)于(yu)20kV為(wei)不(bu)合格品(pin)(pin)。通過(guo)(guo)灌(guan)(guan)封(feng)(feng)(feng)(feng)產品(pin)(pin)的(de)高(gao)低溫強(qiang)化(hua)耐(nai)久試驗(yan)和路況試驗(yan)也(ye)是(shi)手(shou)段之(zhi)一，可(ke)觀測其(qi)是(shi)否有開裂、擊穿或膨脹等問題出(chu)(chu)現(xian)，不(bu)同(tong)(tong)(tong)批次均有出(chu)(chu)現(xian)，可(ke)判定灌(guan)(guan)封(feng)(feng)(feng)(feng)料(liao)(liao)為(wei)不(bu)合格品(pin)(pin)。環(huan)氧樹(shu)(shu)脂(zhi)真空(kong)(kong)灌(guan)(guan)封(feng)(feng)(feng)(feng)系統(tong)，已廣泛應(ying)用(yong)(yong)于(yu)車用(yong)(yong)點火(huo)線(xian)圈(quan)制造行(xing)(xing)(xing)業，而環(huan)氧樹(shu)(shu)脂(zhi)作(zuo)為(wei)絕緣材料(liao)(liao)，在(zai)(zai)不(bu)同(tong)(tong)(tong)產品(pin)(pin)中對其(qi)性能也(ye)有不(bu)同(tong)(tong)(tong)要(yao)求。在(zai)(zai)掌握設(she)備操作(zuo)技術(shu)的(de)基礎上，應(ying)進(jin)(jin)一步(bu)進(jin)(jin)行(xing)(xing)(xing)工(gong)藝(yi)(yi)、設(she)備改進(jin)(jin)，以提高(gao)性能，使其(qi)更好適(shi)應(ying)生產需要(yao)。據專家介紹，樹(shu)(shu)脂(zhi)真空(kong)(kong)灌(guan)(guan)封(feng)(feng)(feng)(feng)工(gong)藝(yi)(yi)，就是(shi)先將(jiang)澆(jiao)(jiao)注(zhu)用(yong)(yong)樹(shu)(shu)脂(zhi)灌(guan)(guan)封(feng)(feng)(feng)(feng)料(liao)(liao)進(jin)(jin)行(xing)(xing)(xing)真空(kong)(kong)脫(tuo)泡處理，再(zai)把經過(guo)(guo)預烘干燥(zao)處理、待封(feng)(feng)(feng)(feng)裝的(de)點火(huo)線(xian)圈(quan)放在(zai)(zai)真空(kong)(kong)澆(jiao)(jiao)注(zhu)室(shi)中進(jin)(jin)行(xing)(xing)(xing)前期真空(kong)(kong)干燥(zao)處理，使線(xian)圈(quan)與(yu)骨架、線(xian)包與(yu)外(wai)殼之(zhi)間的(de)氣體(ti)全部排出(chu)(chu)，然(ran)后在(zai)(zai)真空(kong)(kong)條(tiao)(tiao)件下(xia)用(yong)(yong)完全脫(tuo)過(guo)(guo)泡的(de)已混合好的(de)灌(guan)(guan)封(feng)(feng)(feng)(feng)料(liao)(liao)進(jin)(jin)行(xing)(xing)(xing)封(feng)(feng)(feng)(feng)裝。真空(kong)(kong)灌(guan)(guan)封(feng)(feng)(feng)(feng)設(she)備不(bu)同(tong)(tong)(tong)灌(guan)(guan)封(feng)(feng)(feng)(feng)工(gong)藝(yi)(yi)也(ye)有所不(bu)同(tong)(tong)(tong)，但(dan)是(shi)總體(ti)工(gong)藝(yi)(yi)流程大(da)同(tong)(tong)(tong)小(xiao)(xiao)異(yi)。而在(zai)(zai)相(xiang)同(tong)(tong)(tong)工(gong)藝(yi)(yi)條(tiao)(tiao)件下(xia)材料(liao)(liao)選擇成為(wei)重要(yao)一環(huan)。