Flange seal assembly

This invention relates generally to a flange seal assembly and more particularly to a flange seal assembly utilized with multi-layered plastic fuel tanks. A flange seal assembly for a multi-layered plastic fuel tank having a wall with a permeation barrier layer encapsulated by inner and outer layers. The wall is blow molded about a ring so that the outer layer alone is in actual contact with the ring. The permeation barrier layer is exposed and engaged by a resilient seal. A locking member is located outboard of a flange which engages the seal. Engagement of the locking member with the ring produces a force compressing the seal against the flange and the permeation barrier layer.