Corrugated polymeric filler neck tubing

A filler neck comprising:

• an elongated generally cylindrical filler tube;
• and
• a connector for attaching an end of the filler tube to a fuel tank, the filler tube comprising:
• a generally cylindrical wall having an outer surface and an inner surface, the inner surface approximately parallel to the outer surface and defining a generally cylindrical interior having a diameter D, the cylindrical interior extending longitudinally through the tube coaxial to a longitudinal axis;
• a first longitudinal segment in which D is approximately constant along the longitudinal axis;
• and
• a second longitudinal segment in which D varies with position along the longitudinal axis and is at most between about 20% and about 300% greater than the value of D in the first longitudinal segment, the variation of D defining a convolution for facilitating bending of the filler tube, the cylindrical wall of the multiple-layer tube further comprising:
• an outer layer comprised of a thermoplastic elastomer;
• and
• an inner layer comprised of an extrudable melt-processible thermoplastic having an elongation of at least 150%;
• wherein the outer layer and the inner layer are in non-adhesive contact.

A filler neck comprising:

• an elongated generally cylindrical filler tube;
• and
• a connector for attaching an end of the filler tube to a fuel tank, the filler tube comprising:
• a generally cylindrical wall having an outer surface and an inner surface, the inner surface approximately parallel to the outer surface and defining a generally cylindrical interior having a diameter D, the cylindrical interior extending longitudinally through the tube coaxial to a longitudinal axis;
• a first longitudinal segment in which D is approximately constant along the longitudinal axis;
• and
• a second longitudinal segment in which D varies with position along the longitudinal axis and is at most between about 20% and about 300% greater than the value of D in the first longitudinal segment, the variation of D defining a convolution for facilitating bending of the filler tube, the cylindrical wall of the multiple-layer tube further comprising:
• an outer layer comprised of a crosslinked EPDM rubber dispersed in polypropylene;
• and
• an inner layer comprised of an extrudable melt-processible thermoplastic, wherein the thermoplastic is a twelve-carbon block polyamide, an eleven-carbon block polyamide, or a six-carbon block polyamide, alone or in combination;
• wherein the outer layer and the inner layer are in non-adhesive contact.