Abstract: A packing assembly for a valve includes a first segment having at least one first guiding surface, and a second segment having at least one second guiding surface in engagement with at least a portion of the at least one first guiding surface. A shape-memory member couples the first and second segments. The shape-memory member may be formed of a material that is responsive to changes in temperature, so that, in response to a change in temperature, the shape-memory member may cause relative movement of the first and second segments in a first direction. In response to the movement, the first and second guiding surfaces may cause relative displacement of the first and second segments in a second direction.

Abstract: The present invention provides a polymer indentation method and tester that includes measuring the time taken by a polymeric material to recover a set portion of an initial deformation and use this duration as a material degradation indicator. The recovery time was found to be more sensitive to cable degradation than the specific compressive stillness (or indenter modulus) measured during the indentation phase, and this high sensitivity was achieved for both thermally aged and irradiated polymer.

Abstract: A packing assembly for a valve includes a first segment having at least one first guiding surface, and a second segment having at least one second guiding surface in engagement with at least a portion of the at least one first guiding surface. A shape-memory member couples the first and second segments. The shape-memory member may be formed of a material that is responsive to changes in temperature, so that, in response to a change in temperature, the shape-memory member may cause relative movement of the first and second segments in a first direction. In response to the movement, the first and second guiding surfaces may cause relative displacement of the first and second segments in a second direction.

Abstract: The present invention provides a polymer indentation method and tester that includes measuring the time taken by a polymeric material to recover a set portion of an initial deformation and use this duration as a material degradation indicator. The recovery time was found to be more sensitive to cable degradation than the specific compressive stillness (or indenter modulus) measured during the indentation phase, and this high sensitivity was achieved for both thermally aged and irradiated polymer.

Abstract: The present invention provides a polymer indentation method and tester that includes measuring the time taken by a polymeric material to recover a set portion of an initial deformation and use this duration as a material degradation indicator. The recovery time was found to be more sensitive to cable degradation than the specific compressive stiffness (or indenter modulus) measured during the indentation phase, and this high sensitivity was achieved for both thermally aged and irradiated polymer samples.

Abstract: The present invention provides a polymer indentation method and tester that includes measuring the time taken by a polymeric material to recover a set portion of an initial deformation and use this duration as a material degradation indicator. The recovery time was found to be more sensitive to cable degradation than the specific compressive stiffness (or indenter modulus) measured during the indentation phase, and this high sensitivity was achieved for both thermally aged and irradiated polymer samples.