直接測數法是(shi)憑借照(zhao)布(bu)(bu)鏡或織(zhi)(zhi)物(wu)(wu)密(mi)度(du)分(fen)析鏡來(lai)完成。織(zhi)(zhi)物(wu)(wu)密(mi)度(du)分(fen)析鏡的刻度(du)尺長(chang)度(du)為5cm,在分(fen)析鏡頭下面,一(yi)塊長(chang)條(tiao)(tiao)形玻璃片上(shang)刻有一(yi)條(tiao)(tiao)紅(hong)線(xian), 棉(mian)帆布(bu)(bu) 就(jiu)是(shi)棉(mian)線(xian)布(bu)(bu) 俗(su)稱(cheng)CC56,還有聚酯(zhi)輸(shu)送(song)帶、尼(ni)龍輸(shu)送(song)帶、相比(bi)棉(mian)帆布(bu)(bu)輸(shu)送(song)帶拉(la)力大(da)。棉(mian)帆布(bu)(bu)輸(shu)送(song)帶,適用(yong)于(yu)短(duan)距(ju)離、載量中等條(tiao)(tiao)件下輸(shu)送(song)物(wu)(wu)料(liao),拉(la)力比(bi)較低,承重有一(yi)定的...