Abstract: The trouble with the operation of the washery’s heavy-medium shallow-bath separator is the frequent plugging up of its upward current system.Through analysis of the cause leading to the occurrence of this phenomenon,a remoulding scheme is proposed and implemented on the 305#separator.Practice shows that the structural improvement of the upward current system produces basically no favourable effect on the performance of the separator,and the frequency of blockage of the upward current system is,however,reduced by 80 more percentage points,bringing about a substantially favourable economic benefit for the washery as a result of dramatic reduction of operating cost.