A method for continuously making a tubular polyurethane foam insulation adapted to be installed about a pipe or the like by convolutely winding a continuous web about a mandrel disposed in a stationary mold, the free end of the web extending out through a slot in the mold wall, convolutely winding a second web about the first web having its free end also extend out through the same slot, placing a foamable polyurethane mixture between the two webs while pulling the exposed portions of the webs longitudinally and thereby moving the two radially spaced webs through the mold while the foamable reaction mixture forms longitudinally spit tubular bodies having the first web as a liner and the second web as a cover.