Abstract: The current offshore downhole operation,especially grouting operation in deep wells,is very low in efficiency,In drifting and scraping,sticking and tight tripping are common.An all-in-one cyclone flushing tool had been developed to improve operation efficiency and ensure safety operation.In this paper,through the research of structure,operating principle and some other calculations,after simulation test in laboratory and revision,the all-in-one cyclone flushing tool was developed successfully.Its application in 2 wells of A oilfield showed that the operation efficiency increased by using this tool,and this tool could finish displacing mud and cleaning cuttings in one trip;the improvement in efficiency brought about by this tool would result in economic profit of ￥480 000 per well on average.