Turbine blade having material block and related method

Abstract

A turbine blade including a root section at an end of the turbine blade, a first airfoil section adjacent to the root section, and a tip section adjacent to the airfoil section and including a material block that is incongruous with the airfoil section. A midspan section may also include a material block. Each material block can be selectively machined to customize the length of the turbine blade and the position of a tip shroud connection or midspan connection. The turbine blade can be sized for retrofitting last stage blades of older turbines. A radial position of the root mounts for the turbine blade may also be adjusted to provide further customization.

1 . A turbine blade form comprising:
 a root section at an end of the turbine blade form;   a first airfoil section adjacent to the root section;   a midspan section adjacent to the first airfoil section and including a first material block;   a second airfoil section adjacent to the midspan section; and   a tip section adjacent to the second airfoil section and including a second material block,   wherein the first and second material block are incongruous with any adjacent airfoil section, and   wherein the first and second material block constitute approximately 15 to 25 percent of a length of the turbine blade form.   
     
     
         2 . The turbine blade form of  claim 1 , wherein the first material block is machinable to include a third airfoil section that is congruous with the first and second airfoil sections. 
     
     
         3 . The turbine blade form of  claim 2 , wherein the first material block is machinable to include a midspan connection for mating connection with an adjacent turbine blade at a selected position along the length of the first material block. 
     
     
         4 . The turbine blade form of  claim 1 , wherein the second material block is machinable to include a third airfoil section that is congruous with the second airfoil section. 
     
     
         5 . The turbine blade form of  claim 4 , wherein the second material block is machinable to include a tip shroud connection for mating connection with an adjacent turbine blade at a selected position along the length of the second material block. 
     
     
         6 . The turbine blade form of  claim 1 , wherein the second material block is machinable to selectively define a length of the turbine blade form. 
     
     
         7 . The turbine blade form of  claim 1 , wherein the root section includes a connection for mating with a root mount coupled to a rotating shaft of a multiple stage turbine. 
     
     
         8 . The turbine blade form of  claim 7 , wherein the root mount has a radial position relative to the rotating shaft that is one of less than, greater than, and equal to an adjacent root mount for an adjacent stage of the multiple stage turbine. 
     
     
         9 . The turbine blade form of  claim 1 , wherein the first and second material blocks each have a substantially polyhedron shape except where at least one of the first and second airfoil sections connect to a respective material block. 
     
     
         10 . The turbine blade form of  claim 1 , wherein the turbine blade form is a freestanding blade. 
     
     
         11 . A turbine blade form comprising:
 a root section at an end of the turbine blade form;   a first airfoil section adjacent to the root section; and   a tip section adjacent to the first airfoil section and including a first material block,   wherein the first material block is incongruous with the first airfoil section, and   wherein the first material block is substantially polyhedron in shape.   
     
     
         12 . The turbine blade form of  claim 11 , further comprising:
 a midspan section intersecting the first airfoil section into two adjacent airfoil sections, the midspan section including a second material block,   wherein the second material block is incongruous with the two adjacent airfoil sections.   
     
     
         13 . The turbine blade form of  claim 12 , wherein the second material block is machinable to include another airfoil section that is congruous with the two adjacent airfoil sections and a midspan connection for mating connection with an adjacent turbine blade at a selected position along the length of the first material block. 
     
     
         14 . The turbine blade form of  claim 11 , wherein the first material block is machinable to include another airfoil section that is congruous with the first airfoil section, and a tip shroud connection for mating connection with an adjacent turbine blade at a selected position along the length of the first material block. 
     
     
         15 . The turbine blade form of  claim 11 , wherein the first material block is machinable to selectively define a length of the turbine blade. 
     
     
         16 . The turbine blade form of  claim 12 , wherein the first and second material block constitute approximately 15 to 25 percent of a length of the turbine blade form. 
     
     
         17 . A turbine blade form capable of being machined into a final operative turbine blade comprising:
 a root section at an end of the turbine blade form;   a first airfoil section adjacent to the root section;   a midspan section adjacent to the first airfoil section and including a first material block;   a second airfoil section adjacent to the midspan section; and   a tip section adjacent to the second airfoil section and including a second material block,   wherein the first and second material block are incongruous with any adjacent airfoil section, wherein the first and second material block are substantially polyhedron in shape, and wherein the first and second material block constitute approximately 15 to 25 percent of a length of the turbine blade form.   
     
     
         18 . The turbine blade form of  claim 17 , wherein the root section includes a connection for mating with a root mount coupled to a rotating shaft of a multiple stage turbine. 
     
     
         19 . The turbine blade form of  claim 18 , wherein the root mount has a radial position relative to the rotating shaft that is less than an adjacent root mount for an adjacent stage of the multiple stage turbine. 
     
     
         20 . The turbine blade form of  claim 17 , wherein the midspan section intersects the first airfoil section into two adjacent airfoil sections, and wherein the first material block is incongruous with the two adjacent airfoil sections.