矿山振(zhen)动(dong)筛筛分物料适用于煤、石(shi)(shi)灰石(shi)(shi)、碎石(shi)(shi)、砂砾、金(jin)属或非金(jin)属矿石(shi)(shi)等。

      今天主要(yao)总结一(yi)下关于影响煤(mei)筛分的(de)因(yin)素：

　　一、煤的水分

　　入(ru)料煤(mei)炭的(de)(de)外在(zai)(zai)水(shui)分(fen)是影(ying)响筛(shai)(shai)(shai)分(fen)的(de)(de)主(zhu)要因素(su)，一(yi)(yi)般(ban)外在(zai)(zai)水(shui)分(fen)在(zai)(zai)6%以(yi)下(xia)，可(ke)以(yi)很好地进行干式筛(shai)(shai)(shai)分(fen);如外在(zai)(zai)水(shui)分(fen)超过6%，筛(shai)(shai)(shai)分(fen)困难。冲(chong)水(shui)的(de)(de)湿式筛(shai)(shai)(shai)分(fen)往往取得(de)较好的(de)(de)筛(shai)(shai)(shai)分(fen)效率(lv)。一(yi)(yi)般(ban)筛(shai)(shai)(shai)选厂都采用干式筛(shai)(shai)(shai)分(fen)，选煤(mei)产品可(ke)应用湿式筛(shai)(shai)(shai)分(fen)。在(zai)(zai)外在(zai)(zai)水(shui)分(fen)6%以(yi)下(xia)，筛(shai)(shai)(shai)孔采用13mm可(ke)用一(yi)(yi)般(ban)振动筛(shai)(shai)(shai)进行干式筛(shai)(shai)(shai)分(fen)取得(de)较好效果(guo)，如筛(shai)(shai)(shai)孔6mm进行干筛(shai)(shai)(shai)，用一(yi)(yi)般(ban)筛(shai)(shai)(shai)子则得(de)不(bu)到好的(de)(de)效果(guo)。

　　二、煤(mei)的粒度组成

　　如(ru)果煤中与筛(shai)(shai)孔大小相近的某含量(liang)较少(shao)时，其筛(shai)(shai)分效(xiao)率较高;如(ru)果该粒度(du)的含量(liang)较多，就影响(xiang)透(tou)筛(shai)(shai)的效(xiao)率。但(dan)往往筛(shai)(shai)孔是按国家统一(yi)规(gui)定如(ru)50、25、 13、6mm等分级(ji)的，很少(shao)考虑煤本(ben)身的筛(shai)(shai)分特性。这种与筛(shai)(shai)孔大小相近似的粒度(du)，称为“难(nan)筛(shai)(shai)粒”一(yi)般以在(zai)筛(shai)(shai)孔尺寸(cun)的±25%之内(nei)的煤的产率%计算。

　　三、筛板和(he)筛孔的形状

　　筛(shai)(shai)(shai)(shai)(shai)(shai)分(fen)粒度在25mm以(yi)上(shang)，一般(ban)用冲孔(kong)或(huo)钻(zuan)孔(kong)筛(shai)(shai)(shai)(shai)(shai)(shai)板，孔(kong)眼多数采(cai)用圆(yuan)孔(kong)，菱形排列。25mm以(yi)下(xia)(xia)可(ke)用编(bian)织筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)，编(bian)织筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)为(wei)方孔(kong)。25mm的(de)(de)(de)筛(shai)(shai)(shai)(shai)(shai)(shai)孔(kong)，可(ke)以(yi)用冲孔(kong)筛(shai)(shai)(shai)(shai)(shai)(shai)板，或(huo)编(bian)织筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)，编(bian)织筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)应(ying)防止(zhi)筛(shai)(shai)(shai)(shai)(shai)(shai)条滑动，筛(shai)(shai)(shai)(shai)(shai)(shai)孔(kong)变形。对于1mm以(yi)下(xia)(xia)筛(shai)(shai)(shai)(shai)(shai)(shai)分(fen)(包括脱泥(ni)、脱水、脱介)采(cai)用条缝筛(shai)(shai)(shai)(shai)(shai)(shai)板0.5mm以(yi)下(xia)(xia)的(de)(de)(de)可(ke)以(yi)用条缝筛(shai)(shai)(shai)(shai)(shai)(shai)板(用螺杆(gan)穿筛(shai)(shai)(shai)(shai)(shai)(shai)条上(shang)圆(yuan)环或(huo)焊接(jie)的(de)(de)(de))或(huo)尼龙(long)筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)。不论是筛(shai)(shai)(shai)(shai)(shai)(shai)板或(huo)筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)，本(ben)身须绷紧，并和筛(shai)(shai)(shai)(shai)(shai)(shai)箱(xiang)紧固，这是十分(fen)重(zhong)要的(de)(de)(de)。既可(ke)以(yi)延长筛(shai)(shai)(shai)(shai)(shai)(shai)板、筛(shai)(shai)(shai)(shai)(shai)(shai)网(wang)、筛(shai)(shai)(shai)(shai)(shai)(shai)箱(xiang)的(de)(de)(de)寿命，提高筛(shai)(shai)(shai)(shai)(shai)(shai)分(fen)效率，而且可(ke)以(yi)减轻噪音。

　　对于(yu)50mm以上(shang)的(de)筛板，经(jing)常由钢筋或轻轨(gui)(gui)制(zhi)成。尤其是固定(ding)筛使用旧钢轨(gui)(gui)更是合适。棒形筛条(tiao)都制(zhi)成楔形的(de)，上(shang)宽下(xia)窄，便于(yu)物料通过。

　　圆形(xing)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)，以(yi)圆的(de)(de)(de)(de)直径标明筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)的(de)(de)(de)(de)大(da)小，能保证通(tong)过(guo)的(de)(de)(de)(de)粒(li)(li)度(du)都小于(yu)(yu)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)的(de)(de)(de)(de)尺寸(cun)，其(qi)筛(shai)(shai)(shai)(shai)下产(chan)(chan)品基本不含大(da)于(yu)(yu)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)的(de)(de)(de)(de)大(da)小，但(dan)天上(shang)石麟形(xing)的(de)(de)(de)(de)对角线是边长(zhang)的(de)(de)(de)(de) 1.414倍(bei)，有的(de)(de)(de)(de)资料认为通(tong)过(guo)方孔(kong)(kong)(kong)的(de)(de)(de)(de)*大(da)颗粒(li)(li)，相当于(yu)(yu)通(tong)过(guo)圆孔(kong)(kong)(kong)的(de)(de)(de)(de)*大(da)粒(li)(li)度(du)的(de)(de)(de)(de)1.23倍(bei)。矩(ju)形(xing)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)以(yi)矩(ju)形(xing)的(de)(de)(de)(de)短边作(zuo)为筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)的(de)(de)(de)(de)名义(yi)尺寸(cun)，在这(zhei)种情况下，超(chao)过(guo)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)尺寸(cun)的(de)(de)(de)(de)粒(li)(li)度(du)，特别是扁平(ping)颗粒(li)(li)将顺着(zhe)筛(shai)(shai)(shai)(shai)眼长(zhang)边透筛(shai)(shai)(shai)(shai)。还(hai)有一些不规(gui)则形(xing)状(zhuang)的(de)(de)(de)(de)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)，如一些编织筛(shai)(shai)(shai)(shai)网。概率(lv)筛(shai)(shai)(shai)(shai)的(de)(de)(de)(de)筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)常大(da)于(yu)(yu)分离粒(li)(li)度(du)而用筛(shai)(shai)(shai)(shai)孔(kong)(kong)(kong)的(de)(de)(de)(de)投影进行计算。无论如何(he)，筛(shai)(shai)(shai)(shai)分产(chan)(chan)品的(de)(de)(de)(de)粒(li)(li)度(du)是衡(heng)量粒(li)(li)度(du)标准(zhun)。

　　四、 筛面的长度(du)和宽(kuan)度(du)

　　筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)的(de)(de)宽度决定筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)机(ji)的(de)(de)处理能力，若筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)宽物料的(de)(de)通过(guo)能力大;筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)的(de)(de)长(zhang)(zhang)度决定筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)机(ji)的(de)(de)筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)效(xiao)率(lv)，筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)越(yue)长(zhang)(zhang)物料经过(guo)筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)的(de)(de)时间越(yue)长(zhang)(zhang)，筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)越(yue)彻(che)底，但(dan)是(shi)，过(guo)长(zhang)(zhang)的(de)(de)筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)对(dui)提(ti)高(gao)筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)效(xiao)率(lv)并不显著，而(er)仅仅多余地加(jia)长(zhang)(zhang)了筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)机(ji)的(de)(de)尺(chi)寸。我国现有筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)机(ji)其(qi)筛(shai)(shai)(shai)(shai)(shai)面(mian)(mian)(mian)(mian)长(zhang)(zhang)度，粗粒级的(de)(de)筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)3.5~4m，中细(xi)粒级的(de)(de)筛(shai)(shai)(shai)(shai)(shai)分(fen)(fen)(fen)5.5~5.6m，脱水、脱介6.5m。

　　五、筛面的倾角

　　筛(shai)(shai)(shai)(shai)面(mian)(mian)(mian)倾(qing)角(jiao)的(de)(de)(de)大(da)小，影响筛(shai)(shai)(shai)(shai)上(shang)(shang)物(wu)料的(de)(de)(de)移动(dong)(dong)速度。倾(qing)角(jiao)大(da)，物(wu)料的(de)(de)(de)移动(dong)(dong)快(kuai)，处(chu)理能力高。筛(shai)(shai)(shai)(shai)面(mian)(mian)(mian)的(de)(de)(de)倾(qing)角(jiao)和筛(shai)(shai)(shai)(shai)子的(de)(de)(de)结构形式(shi)与筛(shai)(shai)(shai)(shai)分(fen)产品的(de)(de)(de)质量(liang)要(yao)求有(you)关(guan)。一般(ban)筛(shai)(shai)(shai)(shai)孔在(zai)50mm以上(shang)(shang)，作预先(xian)筛(shai)(shai)(shai)(shai)分(fen)时，都采用圆运动(dong)(dong)筛(shai)(shai)(shai)(shai)分(fen)机(ji)，如惯性(xing)振动(dong)(dong)筛(shai)(shai)(shai)(shai)和自定中心振动(dong)(dong)筛(shai)(shai)(shai)(shai)，其(qi)倾(qing)角(jiao)为15°~20°。而(er)直线运动(dong)(dong)的(de)(de)(de)筛(shai)(shai)(shai)(shai)分(fen)机(ji)，一般(ban)作水(shui)平安装，其(qi)倾(qing)角(jiao)为零度，物(wu)料在(zai)筛(shai)(shai)(shai)(shai)面(mian)(mian)(mian)上(shang)(shang)运动(dong)(dong)，依靠筛(shai)(shai)(shai)(shai)面(mian)(mian)(mian)对物(wu)料的(de)(de)(de)抛射力，这种筛(shai)(shai)(shai)(shai)分(fen)机(ji)一般(ban)用于煤的(de)(de)(de)脱(tuo)水(shui)、脱(tuo)泥(ni)和脱(tuo)介。

　　六、 振幅和频(pin)率

　　振(zhen)(zhen)幅(fu)(fu)是(shi)指(zhi)筛(shai)箱(xiang)行程的一半，频(pin)率是(shi)指(zhi)筛(shai)箱(xiang)分(fen)种往(wang)复振(zhen)(zhen)动(dong)(dong)(dong)的次数。筛(shai)箱(xiang)除(chu)筛(shai)面倾角(jiao)外必须具备足够大的速度才能使筛(shai)面上(shang)的物(wu)料前进。经(jing)试验(yan)研究得(de)出(chu)煤用振(zhen)(zhen)动(dong)(dong)(dong)筛(shai)筛(shai)箱(xiang)的加速度不超(chao)过70~80m/s2,振(zhen)(zhen)幅(fu)(fu)大致为(wei)(wei)2~5mm，转速为(wei)(wei)800~1500r/min。为(wei)(wei)了测量(liang)直线(xian)运动(dong)(dong)(dong)筛(shai)分(fen)机(ji)的振(zhen)(zhen)幅(fu)(fu)，一般直线(xian)振(zhen)(zhen)动(dong)(dong)(dong)筛(shai)筛(shai)帮上(shang)都画着(zhe)测量(liang)振(zhen)(zhen)幅(fu)(fu)的三(san)(san)角(jiao)形(xing)，在测量(liang)三(san)(san)角(jiao)形(xing)画着(zhe)一组平行于(yu)基线(xian)的平行线(xian)，上(shang)面标(biao)有(you)刻(ke)度，表示(shi)三(san)(san)角(jiao)形(xing)相应截割的宽(kuan)度。当筛(shai)箱(xiang)振(zhen)(zhen)动(dong)(dong)(dong)，人在视觉上(shang)的滞留，将看到(dao)两个(ge)三(san)(san)角(jiao)形(xing)，斜边的交点所指(zhi)截宽(kuan)，就是(shi)筛(shai)分(fen)机(ji)的行程(两倍的振(zhen)(zhen)幅(fu)(fu))。

　　七、抛射角

　　抛射(she)角(jiao)是筛箱运(yun)动(dong)方(fang)向与(yu)筛面所形成的角(jiao)度。如抛射(she)角(jiao)较(jiao)大，有利于(yu)物料(liao)透(tou)筛，但(dan)处理量(liang)较(jiao)小(xiao)。直线运(yun)动(dong)筛主要(yao)靠抛射(she)作(zuo)用(yong)推动(dong)物料(liao)前进，并使细粒透(tou)筛。直线运(yun)动(dong)筛的抛射(she)角(jiao)一般(ban)在30°~55°之间(jian)，我(wo)国采用(yong)45°，圆运(yun)动(dong)筛分机(ji)，也有抛射(she)作(zuo)用(yong)，但(dan)其抛射(she)角(jiao)不固定(ding)，并与(yu)筛分机(ji)的频率和振(zhen)幅有关。

　　八、 处理量

　　过大的(de)加大处(chu)理量(单(dan)位(wei)面(mian)积或是(shi)单(dan)位(wei)宽度的(de)处(chu)理量)，严重的(de)影(ying)响筛(shai)(shai)分效率，使筛(shai)(shai)上物中含小于筛(shai)(shai)孔粒级(ji)的(de)数量增(zeng)加。