US Patent 7717473 Dual walled transfer tube

A dual walled transfer tube connecting two sub-flow systems and conveying the system fluid from one subsystem to another when there are large radial and axial movements or offsets between the connecting ends of the subsystem. The dual walled transfer tube has a fitting at either end and a single ball joint proximate each fitting to allow the transfer tube to accommodate changes in radial position of the fittings. The dual walled transfer tube utilizes a main inner fluid passage and an outer secondary fluid passage, each fluid passage having a slip joint to allow the transfer tube to accommodate changes in axial length between the fittings.