LAMINATED FUEL AND VAPOR RETURN LINES

摘要

A multi-layer hydrocarbon vapor-impermeable tube (11) is formed with a nylon outer layer (12) and a vapor barrier inner layer (15) such as ETFE, bonded together by two adhesive layers. The laminated tube is coextruded. The shear on the two adhesive layers are adjusted to bias the first adhesive layer (13) towards the nylon outer layer and the second adhesive layer (14) towards the ETFE barrier layer (15). This permits rapid coextrusion of the laminated tubing. Preferably, both adhesive layers are formed from a blend of nylon and ETFE. The ratio of nylon to ETFE can be adjusted so that the first adhesive layer is preferentially adherent to the nylon layer, and the second adhesive layer is preferentially adherent to the ETFE layer, and both adhesive layers are adherent to each other.