Technoform Caprano+brunnhofer Kg

Edwin Brunnhofer

A layered tubing for use in a motor vehicle has a thick tubular inner layer formed of one or more sublayers of a synthetic resin having a predetermined hardness and a predetermined thickness and designed for use in a temperature range down to -40.degree. C., and a thin tubular outer crack-absorbing layer bonded externally to and surrounding the inner layer. The outer crack-absorbing layer is formed of a synthetic resin resistant to attach by lacquer solvent over the temperature range of the inner layer and having a hardness equal to at most 0.8 of the hardness of the inner layer and a thickness equal to at most 0.5 of the thickness of the inner layer. When lacquer is intentionally or accidentally applied to such tubing and the tubing subsequently is flexed at extremely low temperatures, the lacquer will crack but the soft outer layer will not transmit the sudden change in shape and energy to the inner layer, causing a crack therein. Instead the soft outer layer will absorb the energy of the crack, leaving the underlying tubing intact and free of cracks.

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Guxhagen, Germany

Edwin Brunnhofer