Patent ID: 7469935

Claim:
A pipe fitting for connecting at least two pipes, which pipe fitting comprises at least an innermost layer and an outer layer in such a way that the innermost layer is made of a material different from the outer layer, and that the innermost layer is made of plastic tolerating high temperatures, and that the outer layer is formed of such a material that the outer layer is arranged to function as the provider of oxygen diffusion protection and/or the UV protector, wherein the materials of the different layers are selected in such a way that the outer layer is in contact with but not secured to the innermost layer, such that the surfaces of the innermost layer and the outer layer are able to move relative to each other, wherein the innermost layer is made of polyphenyl sulphone, polysulphone, polyvinylidene fluoride, polyketone, or polyether ketone, and wherein the outer layer is made of polyamide, polypropylene, polyethylene, acrylonitrile-butadiene-styrene, or a copolymer containing styrene.