Turbine rotor blade

Abstract

It is possible to easily and rapidly slot a blade root of a final (last) turbine rotor blade into a blade groove on a turbine disc even when the plan-view shape of a shroud of the turbine rotor blade is complex. A turbine rotor blade that is provided with a blade root that is slotted into a blade groove formed on a circumferential portion of the turbine disc to hold the whole blade, a blade portion that is exposed to high-temperature gas, a platform that supports this blade portion, a shank that connects the blade root and the platform, and a shroud that extends along the circumferential direction from the end of the blade portion has a cut-out portion cut out to a predetermined depth, either at the leading-edge or the trailing-edge of the blade root, along the lengthwise direction thereof from the end of the blade root to an intermediate part of the shank.

1 . A turbine rotor blade provided with a blade root that is slotted into a blade groove formed on a circumferential portion of a turbine disc to hold the whole blade, a blade portion that is exposed to high-temperature gas, a platform that supports this blade portion, a shank that connects the blade root and the platform, and a shroud that extends along the circumferential direction from an end of the blade portion, the turbine rotor blade comprising:
 a cut-out portion that is cut out to a predetermined depth, either at the leading-edge or the trailing-edge of the blade root, along the lengthwise direction thereof, from the end of the blade root to an intermediate part of the shank.   
     
     
         2 . A turbine rotor comprising:
 at one turbine rotor blade according to  claim 1 ;   a plurality of normal blades provided with a blade root that is slotted into a blade groove formed on the circumferential portion of the turbine disc to hold the whole blade, a blade portion that is exposed to high-temperature gas, a platform that supports this blade portion, a shank that connects the blade root and the platform, and a shroud that extends along the circumferential direction from the end of the blade portion; and   the turbine disc.   
     
     
         3 . A method for constructing a turbine rotor by slotting:
 at least one turbine rotor blade provided with a blade root that is slotted into a blade groove formed on a circumferential portion of a turbine disc to hold the whole blade, a blade portion that is exposed to high-temperature gas, a platform that supports this blade portion, a shank that connects the blade root and the platform, a shroud that extends along the circumferential direction from the end of the blade portion, and a cut-out portion that is cut out to a predetermined depth, either at the leading edge or the trailing edge of the blade root, along the lengthwise direction thereof from the end of the blade root to an intermediate part of the shank; and   a plurality of normal blades provided with a blade root that is slotted into a blade groove formed on the circumferential portion of the turbine disc to hold the whole blade, a blade portion that is exposed to high-temperature gas, a platform that supports this blade portion, a shank that connects the blade root and the platform, and a shroud that extends along the circumferential direction from the end of the blade portion; into the turbine disc to complete the turbine rotor, the method for constructing the turbine rotor comprising,   a step of positioning the turbine rotor blade between the normal blades by moving the turbine rotor blade radially inward from radially outward, between the normal blades whose blade roots have been slotted into the blade grooves on the turbine disc to a predetermined depth, and thereafter, slotting the blade roots of the turbine rotor blade and the normal blades into the blade grooves on the turbine disc by moving the turbine rotor blade and the normal blades in the axis line direction of the turbine rotor.