Abstract: A method of forming a tube joint which can be used in a desalination plant includes providing a fluted tube, applying a sealant to the tube end and inserting the tube end into a tube sheet or plate to form a joint therebetween. After insertion, the inner surface of the fluted tube is worked to deform external ridges of the fluted tube and uniformly distribute the sealant throughout the joint area. The fluted tube is deformed using a roll expanding method. The fluted design of the tube retains sealant in the joint area during tube insertion and expansion and takes advantage of the heat transfer characteristic of the flutes to provide an improved joint construction especially adapted for heat exchange use.