# US 2014/0154081 A1 · Tear-drop shaped part-span shroud > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154081 A1 - Document ID: US20140154081A1 - Status: Published application - Kind: A1 - Application number: 13/691,478 - Filed: 2012-11-30 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Rohit CHOUHAN - Web page: https://patentgrep.com/patent/US20140154081A1 ## CPC - F01D 5/225: {by shrouding} - F01D 5/22: Blade-to-blade connections, {e.g. for damping vibrations} - F05D 2250/74: given by a set or table of xyz-coordinates - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A rotatable blade for use in a turbomachine includes an airfoil portion having a leading edge, a trailing edge a radially-inner end and a radially-outer end; a root section affixed to the radially-inner end of the airfoil portion. A part-span shroud is located on the airfoil portion between the root section and the radially-outer end. The part-span shroud is substantially tear-drop shaped such that its cross-sectional shape has a maximum thickness located within 20 to 40% of a chord length extending between leading and trailing edges of the part-span shroud, as measured from the leading edge of the part-span shroud. ## Claims ### Claim 1 A rotatable blade for a turbomachine comprising: an airfoil portion having a leading edge and a trailing edge, a radially-inner end and a radially-outer end; a root section affixed to the radially-inner end of the airfoil portion; and a substantially tear-drop shaped part-span shroud located on the airfoil portion between the root section and the radially outer end, wherein said part-span shroud is provided with a cross-sectional shape having a maximum thickness located within 20 to 40% of a chord length extending from a leading edge of said part-span shroud to a trailing edge of said part-span shroud, as measured from said leading edge of said part-span shroud. ### Claim 2 (depends on 1) The rotatable blade of claim 1, wherein said maximum thickness is located at about 30% of said chord length. ### Claim 3 (depends on 1) The rotatable blade of claim 1, wherein said said maximum thickness is located between 31% and 37% of said chord length. ### Claim 4 (depends on 1) The rotatable blade of claim 1, wherein said maximum thickness is located at 31% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table I. ### Claim 5 (depends on 1) The rotatable blade of claim 1, wherein said maximum thickness is located at 36% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table II. ### Claim 6 (depends on 1) The rotatable blade of claim 1, wherein said maximum thickness is located at 37% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table III. ### Claim 7 (depends on 1) The rotatable blade of claim 1 wherein the part-span shroud is located substantially midway along a radial length of the airfoil portion. ### Claim 8 (depends on 1) The rotatable blade of claim 1 wherein the rotating blade operates as one of: a front stage blade in a compressor, a latter stage blade in a gas turbine, or a low pressure section blade in a steam turbine. ### Claim 9 (depends on 1) The rotatable blade of claim 1 wherein part-span shrouds on respective pressure and suction sides of adjacent ones of said blades at least partially engage along adjacent, substantially Z-shaped contact surfaces. ### Claim 10 (depends on 1) The rotatable blade of claim 1 wherein part-span shrouds on respective pressure and suction sides of adjacent ones of said blades have substantially-straight contact surfaces. ### Claim 11 A turbomachine comprising: a rotor rotatably mounted within a stator, the rotor including: a shaft; at least one rotor wheel mounted on the shaft, each of the at least one rotor wheels including a plurality of radially outwardly extending blades mounted thereon; and wherein each blade includes an airfoil portion having a leading edge and a trailing edge, a radially-inner end and a radially-outer end, a pressure side and a suction side; a root section at the radially-inner end of said airfoil portion; and a part-span shroud located on said airfoil portion between said root section and said radially outer end, on said pressure side and said suction side, wherein said part-span shroud is provided with a substantially tear-drop cross-sectional shape having a maximum thickness located within 20 to 40% of a chord length extending between a leading edge of said part-span shroud and a trailing edge of said part-span shroud, as measured from said leading edge of said part-span shroud. ### Claim 12 (depends on 11) The turbomachine of claim 11 wherein said maximum thickness is located at 31% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table I. ### Claim 13 (depends on 11) The turbomachine of claim 11, wherein said maximum thickness is located at 36% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table II. ### Claim 14 (depends on 11) The turbomachine of claim 11, wherein said maximum thickness is located at 37% of said chord length and wherein said part-span shroud has a profile defined by the X-Y coordinates set forth in Table III. ### Claim 15 (depends on 11) The turbomachine of claim 11, wherein said blade operates as one of: a front stage blade in a compressor, a latter stage blade in a gas turbine, or a low pressure section blade in a steam turbine. ### Claim 16 (depends on 11) The turbomachine of claim 11 wherein said part-span shroud is located substantially midway along a radial length of said airfoil portion. ### Claim 17 A turbomachine comprising: a rotor rotatably mounted within a stator, the rotor including: a shaft; at least one rotor wheel mounted on the shaft, each of the at least one rotor wheels including a plurality of radially outwardly extending blades mounted thereon; and wherein each blade includes an airfoil portion having a leading edge and a trailing edge, a radially-inner end and a radially-outer end, a pressure side and a suction side; a root section at the radially-inner end of said airfoil portion; and a part-span shroud located on said airfoil portion between said root section and said radially outer end, on said pressure side and said suction side, wherein said part-span shroud is provided with a substantially tear-drop cross-sectional shape having a maximum thickness located at 31%, 36% or 37% of a chord length extending between a leading edge of said part-span shroud and a trailing edge of said part-span shroud, as measured from said leading edge of said part-span shroud; and wherein said part-span shroud is disposed on the airfoil portion between about 40% to 80% of a radial height of said airfoil portion as measured from the root section of the blade. ### Claim 18 (depends on 17) The turbomachine of claim 17 wherein said part-span shroud has a profile defined by the X-Y coordinates as set forth in any one of Tables respectively, or by geometric scaling of said coordinates. ### Claim 19 (depends on 17) The turbomachine of claim 17 wherein part-span shrouds on respective pressure and suction sides of adjacent ones of said blades at least partially engage along adjacent, substantially straight or Z-shaped contact surfaces. ### Claim 20 (depends on 17) The turbomachine of claim 17 wherein said part-span shroud is located substantially midway along said radial height of said airfoil portion.