Abstract: This paper introduced the structure and working principle of teetering-bed separator with pulsation damping,and separation tests were processed with it to separation the ＜1.5 mm size coarse slime in Xuehu coal preparation plant,determined the best upward flow rate and the size fraction of the feeding material,based on that tested and analyzed the factors affecting its separation result.The results show that the best range of feed size is 0.2 ～ 0.9 mm;The material concentration have certain effects on the separation result,the separation is best when the liquid-solid ratio is 1.5 ∶1 ～ 1 ∶0.5;the effect of pulsating flow on the production yield is limited,and on the change of ash content of the product will with the variation of the upward flow rate.