Gas riser with free rotating plastic riser casing

摘要

A riser assembly to transmit gas from a buried fluid line to a manifold. Inner (50) and outer (90) casings are received in a first end of an adapter (54). The other end of the adapter (60) is secured to the manifold. A gripping assembly (70) holds the inner casing in the adapter and prevents a pullout while also providing a sealed inner face between the inner casing and the adapter. A mounting assembly is provided to secure the outer casing in the adapter. It, too, prevents pullout of the outer casing and also allows the outer casing to freely rotate relative to the adapter. In selected embodiments the outer casing is formed of a non-corrosive material such as a PVC or polyethelene to address corrosion resistant properties.