PCT No. PCT/SE86/00103 Sec. 371 Date Dec. 19, 1986 Sec. 102(e) Date Dec. 19, 1986 PCT Filed Mar. 11, 1986 PCT Pub. No. WO86/05437 PCT Pub. Date Sep. 25, 1986.Method in extruding a double-walled plastic tube by using plastic materials of different colors for the inner layer and the outer layer, a portion of the material for the inner layer being diverted to form a longitudinal strip of the outer layer on the outside surface of the tube. The invention also relates to an extrusion tool for working the method, wherein an element (21) is provided inside the tool to divert material from a passage (19) for material for the inner layer to a passage (16) for material for the outer layer.
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