Steam turbine, system, and method of operation

Embodiments of the invention relate generally to steam turbines (200, 400), steam turbine systems, and methods for their operation and, more particularly, to high-pressure - intermediate-pressure (HPIP) steam turbine configurations having pressure drop-limited seals and exhibiting reduced mid-packing (230) and/or end-packing (470, 430A-B, 490) leakage. One embodiment of the invention provides a combined high-pressure - intermediate-pressure (HPIP) steam turbine (200) comprising: a high-pressure section (210); an intermediate-pressure section (250) sharing a common rotor (234) with the high-pressure section (210); at least one packing ring (240A-C) disposed along a length of the rotor (234) and between the high-pressure section (210) and the intermediate-pressure section (250); and at least one conduit (264) having a first end (264A) disposed adjacent a packing ring (240C) and a second end (264B) disposed adjacent a steampath stage (212E) of the high-pressure section (210).