SEAL STRUCTURE OF ROTARY MACHINE

摘要

A seal structure capable of actively controlling the operation of a movable seal ring to increase the sealing performance and enhance the reliability. The seal structure (41) in which a high-pressure part and a low-pressure part are partitioned from each other comprises the movable seal ring (73). The movable seal ring (73) comprises spring back seal rings (51) on the high pressure side and ACC seal rings (49) and a fin (71) on the low pressure side. A part of the ACC seal rings (49) constitute the seal rings (73) movable in the generally radial direction. The adjustable movable seal ring (73) partitions the seal structure between a high-pressure side steam chamber (43) and an intermediate-pressure side steam chamber (45) by the fin (71) and the peripheral surface (83). An equalizer pipe (47) connected to a high-pressure outlet part (25) is disposed on the low pressure side of the adjustable movable seal ring (73). An adjustment pipe (55) for connecting a high-pressure dummy (39) to the high-pressure outlet part (25) used for the intermediate- pressure side steam chamber (45) and an open/close valve (57) in the adjustment pipe (55) are disposed on the high-pressure side steam chamber (43) side of the ACC seal ring (49).