Composite tubular woven seal for steam turbine diaphragm horizontal joint interfaces

摘要

Upper and lower diaphragms of a steam turbine have mating flanges forming a horizontal midline joint interface. Each flange has a groove which registers with a corresponding groove in the opposite flange. A composite woven tubular seal is provided in the mating grooves. The seal comprises an inner woven metal core surrounded by an annular silica fiber layer, in turn surrounded by a metal foil with an outer protective covering of a braided stainless steel. Upon joining the diaphragms to one another, the compliant seal generally conforms to a maximum to the shape of the grooves, maintaining a seal between the diaphragms along the horizontal midline joint.