A turbine that includes a rotor, an inner turbine shell, an outer turbine shell, and a sliding engagement between the inner turbine shell and the outer turbine shell. The inner turbine shell is a single piece construction that completely surrounds at least a portion of the rotor, and the outer turbine shell surrounds the inner turbine shell. A method for aligning turbine components that includes aligning a single-piece inner turbine shell substantially concentric with a rotor and surrounding the single-piece inner turbine shell with an outer turbine shell. The method further includes supporting the single-piece inner turbine shell with respect to the outer turbine shell using a bearing assembly between the single-piece inner turbine shell and the outer turbine shell.
FEDERAL RESEARCH STATEMENT
 This invention was made with Government support under contract number DE-FC26-05NT42643 awarded by the Department of Energy. The Government may have certain rights in the invention.