歐式起重設備的調速系統有什么特點
(1)具有(you)良好(hao)的(de)低速(su)、高(gao)速(su)性(xing)能。低速(su)可以實(shi)現(xian)物體的(de)準確定位(wei),高(gao)速(su)可滿(man)足提高(gao)生產率(lv)的(de)要求,妥善解決(jue)準確到位(wei)和高(gao)生產率(lv)的(de)矛盾(dun)。
(2)具有(you)(you)良好的起動、制(zhi)動特性,抑(yi)制(zhi)有(you)(you)害的沖擊。
當重物(wu)在上升(sheng)方向加速時,負(fu)載的(de)(de)(de)加速轉矩會(hui)(hui)對機(ji)(ji)(ji)械設備產生(sheng)巨大(da)沖擊(ji);下降減速停(ting)車時,由于機(ji)(ji)(ji)械制(zhi)動(dong)器參與減速和停(ting)車,因此也會(hui)(hui)產生(sheng)過(guo)載沖擊(ji)。這(zhe)些有害的(de)(de)(de)機(ji)(ji)(ji)械沖擊(ji),影響機(ji)(ji)(ji)械部(bu)件(jian)(jian)、起重機(ji)(ji)(ji)的(de)(de)(de)鋼(gang)結構(特別是大(da)梁(liang))、機(ji)(ji)(ji)械制(zhi)動(dong)部(bu)件(jian)(jian)的(de)(de)(de)壽命(ming)。另一方面(mian),當電機(ji)(ji)(ji)在加速和減速時,會(hui)(hui)產生(sheng)很大(da)的(de)(de)(de)電流。過(guo)大(da)的(de)(de)(de)電流將引起電機(ji)(ji)(ji)發熱,影響電機(ji)(ji)(ji)壽命(ming)。
因此,特別(bie)是大噸位、高(gao)速(su)頻繁(fan)作業的(de)(de)起重設(she)備(bei),對(dui)調速(su)系統的(de)(de)起動(dong)、制動(dong)特性要求更高(gao)。
為(wei)了(le)抑制(zhi)有(you)害的(de)機(ji)械(xie)(xie)沖(chong)擊,在重(zhong)物加速(su)(su)上(shang)升時(shi),調速(su)(su)系(xi)統能夠有(you)效地(di)控(kong)制(zhi)加速(su)(su)度(du)(du)值;在重(zhong)物下降減速(su)(su)時(shi),調速(su)(su)系(xi)統能夠按照(zhao)設(she)置的(de)減速(su)(su)度(du)(du)進行電制(zhi)動,等待速(su)(su)度(du)(du)降到低(di)速(su)(su)后,才進行機(ji)械(xie)(xie)制(zhi)動,在機(ji)械(xie)(xie)制(zhi)動器完全閉合前,保(bao)持(chi)電制(zhi)動轉矩。這樣,確保(bao)了(le)制(zhi)動平(ping)穩、防(fang)止了(le)重(zhong)物的(de)下溜。
(3)減少(shao)或避(bi)免點動(dong)(dong)操作(zuo)次數,減少(shao)機(ji)械部件(jian)和(he)電(dian)動(dong)(dong)機(ji)、電(dian)器(qi)元(yuan)件(jian)的(de)沖擊,提高電(dian)器(qi)元(yuan)件(jian)的(de)使用壽(shou)命。
點動(dong)(dong)操作(zuo)對起(qi)重設(she)備電(dian)(dian)(dian)(dian)(dian)(dian)氣設(she)備的(de)(de)影響很大,點動(dong)(dong)操作(zuo)是指將電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機接通電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan),但不等待電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機起(qi)動(dong)(dong)結(jie)束,就切(qie)斷電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)。使電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機總是工作(zuo)在起(qi)動(dong)(dong)狀態。由(you)于電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機的(de)(de)起(qi)動(dong)(dong)電(dian)(dian)(dian)(dian)(dian)(dian)流大于額定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)流(籠型電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機的(de)(de)起(qi)動(dong)(dong)電(dian)(dian)(dian)(dian)(dian)(dian)流是額定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)流的(de)(de)4~7倍;繞(rao)線電(dian)(dian)(dian)(dian)(dian)(dian)動(dong)(dong)機轉子串電(dian)(dian)(dian)(dian)(dian)(dian)阻的(de)(de)起(qi)動(dong)(dong)電(dian)(dian)(dian)(dian)(dian)(dian)流也是額定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)流的(de)(de)1.8~2.5倍)。
如果點(dian)(dian)動(dong)(dong)操(cao)作(zuo)次(ci)數(shu)多(duo),電(dian)動(dong)(dong)機(ji)的溫(wen)度很(hen)快(kuai)就(jiu)會上(shang)升,極(ji)易損(sun)(sun)壞(huai)電(dian)動(dong)(dong)機(ji)的繞(rao)組。對(dui)于接觸(chu)(chu)器、繼(ji)(ji)(ji)電(dian)器而言,點(dian)(dian)動(dong)(dong)操(cao)作(zuo)次(ci)數(shu)多(duo),就(jiu)是它們的開斷(duan)次(ci)數(shu)多(duo),對(dui)接觸(chu)(chu)器來說是開斷(duan)電(dian)動(dong)(dong)機(ji)的起動(dong)(dong)電(dian)流,這樣,接觸(chu)(chu)器的觸(chu)(chu)頭(tou)磨(mo)損(sun)(sun)大(da)(da)大(da)(da)加(jia)快(kuai);對(dui)繼(ji)(ji)(ji)電(dian)器來說,是開斷(duan)繼(ji)(ji)(ji)電(dian)器繞(rao)組的起動(dong)(dong)電(dian)流,同樣使(shi)繼(ji)(ji)(ji)電(dian)器的觸(chu)(chu)頭(tou)磨(mo)損(sun)(sun)大(da)(da)大(da)(da)加(jia)快(kuai)。所(suo)以點(dian)(dian)動(dong)(dong)操(cao)作(zuo)無論(lun)對(dui)電(dian)動(dong)(dong)機(ji)的繞(rao)組還是接觸(chu)(chu)器、繼(ji)(ji)(ji)電(dian)器的線圈和觸(chu)(chu)頭(tou)都十分不(bu)利,嚴(yan)重影響其使(shi)用壽命。
靖江市起重設備廠,唐(tang)經理: