Coupling member for connecting a fuel receiving or fuel dispensing part to a fluid line and method for its manufacture

A coupling member for connecting a part, provided for receiving or dispensing fuel and made primarily of HDPE (high-density polyethylene), to a fluid line, wherein the coupling member comprises:

• a first component, a second component, and a third component comprised of primarily meltable material;
• wherein the third component is configured to form a heat fusion joint with the part for receiving or dispensing fuel and has an undesirably high permeability and swelling capacity relative to fuel;
• wherein the third component is connected to the first component by at least one of a material bonding action and a positive-locking action;
• wherein the second component has a greater locking capacity relative to fuel than the third component and a higher strength than the third component;
• wherein the material of the second component is embedded completely or mostly in the material of the third component;
• wherein a volume ratio of volumes of the second and third components relative to one another is selected such that combined properties of the second and third components with regard to fuel permeability, strength, and volume changes by swelling are approximated to properties of the second component with regard to fuel permeability, strength, and volume changes by swelling;
• wherein the materials of the first and third components are directly connected together by a heat-fusion connection.