SELF-ADJUSTING SEAL FOR TURBO ROTARY MACHINE

摘要

A self-adjusting seal (1) includes a movable seal member (20) fitted to a groove (6) of a dummy ring (4) and along a rotor (2). The movable seal member (20) is biased outward in the radial direction by a disc spring (30), and the gap between the movable seal member (20) and the rotor (2) is widened when the turbo rotary machine is activated and stopped. During rated operation of the turbo rotary machine, on the other hand, the movable seal member (20) is pressed to the rotor (2) against the biasing force of the disc spring (30) by a fluid flowing into the groove (6) through between a high-pressure end face of the movable seal member (20) and the groove (6). At least one of a low-pressure end face of the movable seal member (20) and a wall surface of the groove (6) facing the low-pressure end face is treated so as to smoothen the sliding movement relative to each other.