Patent ID: 8197211
Filing Date: 2012-06-12
Classification: F01D

Abstract:
1. A composite turbine rotor blade comprising: a blade root with a platform extending outward; a leading edge spar and a trailing edge spar extending from the root and platform; the leading edge spar forming a leading edge region of the blade; the trailing edge spar forming a trailing edge region of the blade; the leading edge spar and the trailing edge spar both forming a radial extending cooling channel; the leading edge spar and the trailing edge spar both having a radial extending rib extending inward from the respective spar; the blade root, the platform and the two spars all being formed from a single piece and from a metallic material; a mid-chord piece having a pressure side wall and a suction side wall and extending from the platform to a blade tip region, the mid-chord piece having a forward side with a radial extending groove and an aft side with a radial extending groove, the two grooves being sized to fit the ribs from the spars to secure the mid-chord piece to the spars; and, a T-shape tip rail piece having a tip rail cooling channel extending from the leading edge spar to the trailing edge spar, the tip rail piece having a hollow radial pin extending from the tip rail channel at around a mid-chord position, the tip rail piece having a row of tip cooling holes extending from the forward end to the aft end, the tip rail piece securing the mid-chord piece to the blade root and platform against radial displacement, and the tip rail piece being made from a high temperature resistant composite material.