IMPROVED SUPPORT ARRANGEMENT FOR OPTIMIZING A LOW PRESSURE STEAM TURBINE INNER CYLINDER STRUCTURAL PERFORMANCE

摘要

56,128 Apparatus is provided for increasing the bending flexibility of the horizontal joint flange of a low pressure steam turbine. The radial width of the horizontal joint flange in the support area where the turbine inner cylinder rests on the outer cylinder has been significantly reduced. In order to accommodate a reduction in the radial width of the flange in this area, the present invention provides a novel arrangement of the functional features of the cylinder support area. In a preferred embodiment the horizontal joint flange is capable of being narrowed in the radial direction due to the strategic rearrangement of the functional components in the support area. The present invention also provides retrofit steps for modifying existing turbines in order to provide the features and benefits of the improved apparatus. The present invention reduces ovality of the turbine inner cylinder rings, resulting in improved thermal performance and mechanical reliability as well as a reduction in flange induced, non-axisymmetric bolt loads in the horizontal joint flange bolts.