Steam Turbine Rotor and Steam Turbine
According to the present invention, the steam turbine rotor includes an embedded fin which includes: a bent bottom part; and an upright part including a fin tip and a fin root, and which is inserted in a fixing groove and fixed in the fixing groove by means of a locking strip, and has an arrangement wherein a static friction coefficient between a side surface of the fixing groove and a side surface of the fin root, a static friction coefficient between a side surface of the locking strip and a side surface of the fin root, and a static friction coefficient between the side surface of the fixing groove and the side surface of the locking strip are increased.
1 . A steam turbine rotor comprising an embedded fin which includes: a bent bottom part; and an upright part including a fin tip and a fin root, and which is inserted in a fixing groove and fixed in the fixing groove by means of a locking strip,
wherein a static friction coefficient between a side surface of the fixing groove and a side surface of the fin root, a static friction coefficient between a side surface of the locking strip and a side surface of the fin root, and a static friction coefficient between the side surface of the fixing groove and the side surface of the locking strip are increased.
2 . The steam turbine rotor according to claim 1 , wherein, of the static friction coefficient between the side surface of the fixing groove and the side surface of the fin root, the static friction coefficient between the side surface of the locking strip and the side surface of the fin root, and the static friction coefficient between the side surface of the fixing groove and the side surface of the locking strip, the static friction coefficient between the side surface of the fixing groove and the side surface of the fin root is the largest.
3 . The steam turbine rotor according to claim 2 , wherein the fixing groove has a width-to-depth ratio of 1:2 or more and 1:4 or less.
4 . The steam turbine rotor according to claim 1 , wherein the side surface of the fin root has a larger surface roughness than the side surface of the fixing groove.
5 . The steam turbine rotor according to claim 1 , wherein the side surface of the locking strip has a larger surface roughness than the side surface of the fixing groove.
6 . The steam turbine rotor according to claim 1 , wherein the fixing groove includes a croze.
7 . A steam turbine comprising the steam turbine rotor according to claim 1 .