(under subclass 118) Device wherein the pipe wall is made up of more than one layer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
101, for distinct layer pipe wherein at least one of the layers is braided, interlaced, knitted or woven.
SEE OR SEARCH CLASS
156, Adhesive Bonding and Miscellaneous Chemical Manufacture, appropriate subclasses for processes and apparatus for forming tubes, etc., with distinct layers by a laminating operation.
428, Stock Material or Miscellaneous Articles, appropriate subclasses, for a stock material product in the form of a single or plural layer web or sheet, and especially 457+, for a nonstructural plural layer web or sheet including at least one layer of metal.
