Patents by Inventor Nanayakkara Liyanage Don Somasiri

Nanayakkara Liyanage Don Somasiri 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).

  • Method for altering cable semiconductive layer
    Patent number: 5973266
    Abstract: A method of altering a portion of the semiconductive layer of an electric power cable, to increase its resistance so as to render it electrically insulative. The semiconductive layer is loaded with carbon powder which forms chains to provide conductive pathways through the layer. By introducing an intercalant into the semiconductive layer, which causes the layer to swell, the conductive pathways are interrupted and the material is rendered insulative (>10.sup.4 .OMEGA.-cm). The intercalant may be a polymerizable material with a curing agent which is cured in situ, i.e., without removing the semiconductive layer from the cable. By this method, flashover to the semiconductive layer at a cable splice or termination may be prevented without requiring tedious removal of the exposed portion of the semiconductive layer. The method is usable with both strippable and coextruded semiconductive layers.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: October 26, 1999
    Assignee: 3M Innovative Properties Company
    Inventors: Gary A. Shreve, Nanayakkara Liyanage Don Somasiri, Justine Anne Mooney, Alan George Hulme-Lowe, Curtis Roy Guilbert
  • Method for altering cable semiconductive layer
    Patent number: 5885651
    Abstract: A method of altering a portion of the semiconductive layer of an electric power cable, to increase its resistance so as to render it electrically insulative. The semiconductive layer is loaded with carbon powder which forms chains to provide conductive pathways through the layer. By introducing an intercalant into the semiconductive layer, which causes the layer to swell, the conductive pathways are interrupted and the material is rendered insulative (>10.sup.4 .OMEGA.-cm). The intercalant may be a polymerizable material with a curing agent which is cured in situ, i.e., without removing the semiconductive layer from the cable. By this method, flashover to the semiconductive layer at a cable splice or termination may be prevented without requiring tedious removal of the exposed portion of the semiconductive layer. The method is usable with both strippable and coextruded semiconductive layers.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: March 23, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gary A. Shreve, Nanayakkara Liyanage Don Somasiri, Justine Anne Mooney, Alan George Hulme-Lowe, Curtis Roy Guilbert
  • Method for altering cable semiconductive layer
    Patent number: 5770257
    Abstract: A method of altering a portion of the semiconductive layer of an electric power cable, to increase its resistance so as to render it electrically insulative. The semiconductive layer is loaded with carbon powder which forms chains to provide conductive pathways through the layer. By introducing an intercalant into the semiconductive layer, which causes the layer to swell, the conductive pathways are interrupted and the material is rendered insulative (>10.sup.4 .OMEGA.-cm). The intercalant may be a polymerizable material with a curing agent which is cured in situ, i.e., without removing the semiconductive layer from the cable. By this method, flashover to the semiconductive layer at a cable splice or termination may be prevented without requiring tedious removal of the exposed portion of the semiconductive layer. The method is usable with both strippable and coextruded semiconductive layers.
    Type: Grant
    Filed: August 1, 1996
    Date of Patent: June 23, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gary A. Shreve, Nanayakkara Liyanage Don Somasiri, Justine Anne Mooney, Alan George Hulme-Lowe, Curtis Roy Guilbert