Patent ID: 8419354

Claim:
A steam turbine comprising: two or more rotating blades; and a diaphragm outer ring arranged on a circumference outside the rotating blades, each of the rotating blades including: a tip cover which is provided to a tip of each of the rotating blades and is connected in contact with another tip cover adjacent to the tip cover; moisture-trapping grooves formed in a longitudinal direction of each of the rotating blades on a leading edge of each of the rotating blades; a droplet ejection hole formed so that the droplet ejection hole connects an outside of the tip cover on a side of the diaphragm outer ring with an inside of the tip cover on a side of each of the rotating blades; and a drain guide groove formed so that the drain guide groove connects ends of the moisture-trapping grooves on the side of the tip cover with the droplet ejection hole, the diaphragm outer ring including a drain pocket which faces the droplet ejection hole.