Patents by Inventor Sudhir Rajagopalan

Sudhir Rajagopalan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for applying a shape memory alloy erosion resistant protective structure onto an airfoil of a turbine blade
    Patent number: 9157139
    Abstract: A component is provided for use in a turbine comprising: a substrate formed from an alloy, and an erosion resistant protective structure mechanically coupled to a portion of the substrate for protecting the substrate portion from erosion caused by a fluid. The erosion resistant protective structure may be formed from a shape memory alloy.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: October 13, 2015
    Assignee: Siemens Energy, Inc.
    Inventor: Sudhir Rajagopalan
  • Turbomachine blade locking structure including shape memory alloy
    Patent number: 8496439
    Abstract: A system for locking blades to a rotor of a turbomachine including adjacent pairs of generally axially extending grooves for receiving blades inserted in an axial direction. A circumferential slot is disposed around the periphery of the rotor and a locking device assembly is located in the circumferential slot between an adjacent pair of grooves. The assembly includes a last locking device, a spacer and key member formed of a shape memory alloy. The key member is located in a gap between the last locking device and the spacer. The shape memory alloy key member is heated to cause a transition from a martensite to an austenite phase to cause the key member to engage and press against opposing faces of the last locking device and the spacer to increase a force applied to a respective pair of blades in the adjacent pair of grooves.
    Type: Grant
    Filed: March 17, 2010
    Date of Patent: July 30, 2013
    Assignee: Siemens Energy, Inc.
    Inventor: Sudhir Rajagopalan
  • Turbomachine Blade Locking Structure Including Shape Memory Alloy
    Publication number: 20110229328
    Abstract: A system for locking blades to a rotor of a turbomachine including adjacent pairs of generally axially extending grooves for receiving blades inserted in an axial direction. A circumferential slot is disposed around the periphery of the rotor and a locking device assembly is located in the circumferential slot between an adjacent pair of grooves. The assembly includes a last locking device, a spacer and key member formed of a shape memory alloy. The key member is located in a gap between the last locking device and the spacer. The shape memory alloy key member is heated to cause a transition from a martensite to an austenite phase to cause the key member to engage and press against opposing faces of the last locking device and the spacer to increase a force applied to a respective pair of blades in the adjacent pair of grooves.
    Type: Application
    Filed: March 17, 2010
    Publication date: September 22, 2011
    Inventor: Sudhir Rajagopalan
  • Method of increasing service interval periods in a steam turbine
    Patent number: 7954323
    Abstract: A method of increasing service interval periods in a steam turbine by neutralizing sodium hydroxide in contaminated steam in a high temperature and a high pressure portion of a steam turbine by placing a protective covering over at least a portion of each of the bolts of a nozzle block assembly. The protective covering neutralizes contaminants in contaminated steam to reduce stress cracking of the bolts during steam turbine operation, and thus extend the useful life of the bolts and reduce the need for service work to repair or replace damaged bolts.
    Type: Grant
    Filed: March 26, 2008
    Date of Patent: June 7, 2011
    Assignee: Siemens Energy, Inc.
    Inventors: James C. Bellows, Sudhir Rajagopalan, James W. Dorow
  • EROSION RESISTANT PROTECTIVE STRUCTURE AND PROCESS FOR APPLYING SAME TO A SUBSTRATE
    Publication number: 20100034661
    Abstract: A component is provided for use in a turbine comprising: a substrate formed from an alloy, and an erosion resistant protective structure mechanically coupled to a portion of the substrate for protecting the substrate portion from erosion caused by a fluid. The erosion resistant protective structure may be formed from a shape memory alloy.
    Type: Application
    Filed: August 8, 2008
    Publication date: February 11, 2010
    Inventor: Sudhir Rajagopalan
  • Method of Increasing Service Interval Periods in a Steam Turbine
    Publication number: 20090241544
    Abstract: A method of increasing service interval periods in a steam turbine by neutralizing sodium hydroxide in contaminated steam in a high temperature and a high pressure portion of a steam turbine by placing a protective covering over at least a portion of each of the bolts of a nozzle block assembly. The protective covering neutralizes contaminants in contaminated steam to reduce stress cracking of the bolts during steam turbine operation, and thus extend the useful life of the bolts and reduce the need for service work to repair or replace damaged bolts.
    Type: Application
    Filed: March 26, 2008
    Publication date: October 1, 2009
    Applicant: SIEMENS POWER GENERATION, INC.
    Inventors: James C. Bellows, Sudhir Rajagopalan, James W. Dorow