影響振動篩工作效率的相關因素--物料性質

       振動篩在生產過程中往往會出現堆積現象,即篩網被堆堵,篩分面(mian)積變小,工藝效率,這主要與物(wu)料(liao)組(zu)成(cheng)類(lei)型和物(wu)料(liao)松散密度(du)、物(wu)料(liao)粒度(du)等(deng)有關(guan)。

1、物料類型和顆粒物料的類型不同,物理特性也不同。物料的類型可分為脆性和粘性兩大類,粘性物料在振動篩分過程中,容易(yi)形成物(wu)料的密實粘(zhan)連,堵塞篩(shai)網,使通(tong)透(tou)(tou)率,而脆性物(wu)料則不然,工(gong)藝效(xiao)率能夠得(de)到(dao)。物(wu)料的顆(ke)粒形狀(zhuang)將影(ying)響物(wu)料的透(tou)(tou)篩(shai)率,立(li)方體形狀(zhuang)和球(qiu)體的物(wu)料易(yi)于透(tou)(tou)篩(shai),而片(pian)狀(zhuang)物(wu)料則易(yi)于卡(ka)在篩(shai)孔中,而影(ying)響工(gong)藝效(xiao)率。

2、料(liao)(liao)(liao)(liao)松散(san)密(mi)度(du)(du)(du)物(wu)料(liao)(liao)(liao)(liao)顆(ke)粒(li)基本上是按照(zhao)顆(ke)粒(li)體積(ji)的(de)大小(xiao)分層與(yu)透篩的(de),即物(wu)料(liao)(liao)(liao)(liao)的(de)松散(san)密(mi)度(du)(du)(du)直接影響振動篩的(de)處理能力。松散(san)密(mi)度(du)(du)(du)較(jiao)大的(de)塊狀物(wu)料(liao)(liao)(liao)(liao)容易透篩,篩分效率(lv)也較(jiao)高;相(xiang)反(fan),松散(san)密(mi)度(du)(du)(du)較(jiao)小(xiao)的(de)物(wu)料(liao)(liao)(liao)(liao)及粉(fen)狀物(wu)料(liao)(liao)(liao)(liao)不容易透篩,篩分效率(lv)較(jiao)低(di)。

3、物(wu)(wu)料(liao)(liao)濕度物(wu)(wu)料(liao)(liao)含(han)泥水(shui)量(liang) 過(guo)高(gao),易形成粘(zhan)連,在振動(dong)(dong)過(guo)程中,物(wu)(wu)塊相互擠壓(ya),粘(zhan)連更加密實,從而(er)增力口物(wu)(wu)料(liao)(liao)運動(dong)(dong)的阻(zu)力,以致物(wu)(wu)料(liao)(liao)顆粒(li)分(fen)(fen)層與透篩(shai)(shai)(shai)(shai)出(chu)現困難;物(wu)(wu)料(liao)(liao)粘(zhan)連也使篩(shai)(shai)(shai)(shai)孔尺(chi)寸變小,堵塞(sai)篩(shai)(shai)(shai)(shai)孔,了(le)篩(shai)(shai)(shai)(shai)分(fen)(fen)面積(ji),含(han)水(shui)量(liang)過(guo)高(gao)的物(wu)(wu)料(liao)(liao)有時(shi)甚至(zhi)無法進行篩(shai)(shai)(shai)(shai)分(fen)(fen)。因此,物(wu)(wu)料(liao)(liao)含(han)水(shui)量(liang)過(guo)高(gao)時(shi),篩(shai)(shai)(shai)(shai)分(fen)(fen)工(gong)藝應考慮一些補救方法,如采取烘干物(wu)(wu)料(liao)(liao)等措施。

4、物(wu)(wu)料顆(ke)(ke)粒(li)(li)度(du)(du)(du)(du)(du)組成物(wu)(wu)料在篩(shai)(shai)(shai)(shai)(shai)(shai)分(fen)過程中(zhong)的透(tou)篩(shai)(shai)(shai)(shai)(shai)(shai)概率(lv)(lv)(lv)受很多(duo)因(yin)素影(ying)響,其中(zhong)直接和重要(yao)的因(yin)素是物(wu)(wu)料粒(li)(li)度(du)(du)(du)(du)(du)與(yu)篩(shai)(shai)(shai)(shai)(shai)(shai)孔尺寸的相(xiang)對(dui)大(da)小(xiao)(xiao)。物(wu)(wu)料粒(li)(li)度(du)(du)(du)(du)(du)與(yu)篩(shai)(shai)(shai)(shai)(shai)(shai)孔尺寸的比(bi)值稱(cheng)為(wei)相(xiang)對(dui)粒(li)(li)度(du)(du)(du)(du)(du)。相(xiang)對(dui)粒(li)(li)度(du)(du)(du)(du)(du)越(yue)(yue)小(xiao)(xiao),透(tou)篩(shai)(shai)(shai)(shai)(shai)(shai)概率(lv)(lv)(lv)越(yue)(yue)高,當相(xiang)對(dui)粒(li)(li)度(du)(du)(du)(du)(du)接近(jin)于(yu)1時,透(tou)篩(shai)(shai)(shai)(shai)(shai)(shai)概率(lv)(lv)(lv)趨近(jin)于(yu)零(ling),因(yin)此通(tong)常把相(xiang)對(dui)粒(li)(li)度(du)(du)(du)(du)(du)等(deng)于(yu)0.7-1的物(wu)(wu)料稱(cheng)為(wei)難篩(shai)(shai)(shai)(shai)(shai)(shai)物(wu)(wu)料或臨界物(wu)(wu)料。物(wu)(wu)料中(zhong)難篩(shai)(shai)(shai)(shai)(shai)(shai)物(wu)(wu)料的含量(liang)(liang)越(yue)(yue)大(da),則透(tou)篩(shai)(shai)(shai)(shai)(shai)(shai)概率(lv)(lv)(lv)越(yue)(yue)小(xiao)(xiao),篩(shai)(shai)(shai)(shai)(shai)(shai)分(fen)效率(lv)(lv)(lv)就會(hui)越(yue)(yue)低(di);反(fan)之篩(shai)(shai)(shai)(shai)(shai)(shai)分(fen)效率(lv)(lv)(lv)越(yue)(yue)高。為(wei)了能(neng)夠得到更高的篩(shai)(shai)(shai)(shai)(shai)(shai)分(fen)效率(lv)(lv)(lv),應該盡量(liang)(liang)集(ji)料中(zhong)難篩(shai)(shai)(shai)(shai)(shai)(shai)物(wu)(wu)料的含量(liang)(liang)。此外,顆(ke)(ke)粒(li)(li)度(du)(du)(du)(du)(du)指數差異對(dui)篩(shai)(shai)(shai)(shai)(shai)(shai)分(fen)效率(lv)(lv)(lv)也有(you)的影(ying)響,顆(ke)(ke)粒(li)(li)度(du)(du)(du)(du)(du)指數差異過大(da)會(hui)造成生產循環大(da),制約了產品的質(zhi)量(liang)(liang)和處(chu)理能(neng)力。因(yin)此,應嚴格控制集(ji)料的級配。