Patents by Inventor Norman Pietruska

Norman Pietruska 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).

  • Patent number: 5741378
    Abstract: An improved method is described for restoring the mechanical properties to carbide-containing Co-based superalloy gas turbine components which have been exposed to high temperatures and pressures for extended periods of time. The method includes solution heat treating to 2250.degree.-2300.degree. F. for one to twelve hours to dissolve complex carbides, and aging at approximately 1965.degree.-1975.degree. F. for two to twenty four hours. The rejuvenated components exhibit excellent high temperature creep properties.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: April 21, 1998
    Assignee: United Technologies Corporation
    Inventors: Norman Pietruska, S. Michael Kurpaska
  • Patent number: 5735448
    Abstract: A repair coating for superalloy articles, such as gas turbine engine components, includes a volatile organic carrier or water-based carrier, a fluxing agent, a thickening agent, balance a filler mix. The filler mix consists of at least two distinct particulate components. The mix includes a first particulate component having a composition which approximates that of the article being repaired. The mix also includes a second particulate component having a composition approximating that of the article and a melting point depressant, such as boron. This melting point depressant is substantially in excess of that in the article and sufficient to provide melting of a portion of the mix at a processing temperature below the melting temperature of the article. The above filler mix is blended with the other constituents to form the repair coating which is applied to an article.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: April 7, 1998
    Assignee: United Technologies Corporation
    Inventors: Peter J. Draghi, Norman Pietruska, Wayne K. Armstrong
  • Patent number: 5549767
    Abstract: An improved method is described for repairing Co-base superalloy gas turbine engine components by applying a mixture of base alloy powder and base alloy powder with a melting point depressant to the surface of the component and heating at 2250.degree.-2300.degree. F. to diffuse the melting point depressant isothermally into the base alloy. A protective coating is then applied, during which a heating cycle which ages the base material is used. The resultant component has high temperature creep properties which are significantly better than achieved using the prior art process. The same temperature cycle is also useful in the initial heat treatment of Co-base superalloys, and can also be used for rejuvenation of components which have experienced extensive exposure to engine operating conditions.
    Type: Grant
    Filed: July 26, 1994
    Date of Patent: August 27, 1996
    Assignee: United Technologies Corporation
    Inventors: Norman Pietruska, S. Michael Kurpaska
  • Patent number: 5522134
    Abstract: A method for refurbishing or restoring a turbine vane or other airfoil to restore a desired flow area includes the steps of: providing a plate to be used to restore the flow area on the airfoil; cutting the plate into a desired shape; machining a series of tapers into the cut plate so that the cut plate has a single region with a substantially uniform thickness; overlaying a surface of the airfoil with the pre-cut, pre-shaped plate so that the substantially uniform thickness region is positioned over that part of the airfoil where the flow area is to be restored; and attaching the pre-cut, pre-shaped plate to the airfoil. The refurbishment or restoration method further includes heat treating the pre-cut, pre-shaped plate so that the plate softens and conforms to the shape of the airfoil surface.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: June 4, 1996
    Assignee: United Technologies Corporation
    Inventors: Jon G. Rowe, Norman Pietruska, Richard J. Pawlaczyk, Gilbert B. Wilcox
  • Patent number: 5437737
    Abstract: A repair coating for superalloy articles, such as gas turbine engine components, includes a volatile organic carrier or water-based carrier, a fluxing agent, a thickening agent, balance a filler mix. The filler mix consists of at least two distinct particulate components. The mix includes a first particulate component having a composition which approximates that of the article being repaired. The mix also includes a second particulate component having a composition approximating that of the article and a melting point depressant, such as boron. This melting point depressant is substantially in excess of that in the article and sufficient to provide melting of a portion of the mix at a processing temperature below the melting temperature of the article. The above filler mix is blended with the other constituents to form the repair coating which is applied to an article.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: August 1, 1995
    Assignee: United Technologies Corporation
    Inventors: Peter J. Draghi, Norman Pietruska, Wayne F. Armstrong