HEAT-SHRINKABLE TUBE MANUFACTURING APPARATUS

摘要

PURPOSE: To produce a thick heat-shrinkable tube of high expansion magnification by uniformly expanding a crosslinked plastic tube being a base material by one process to mold the same so as to form a circular cross section. CONSTITUTION: A guide pipe 1 sending out introduced gas pressure to the outside from the hole provided on the way of the pipe 1 in the longitudinal direction thereof is covered with a crosslinked plastic tube A and, after both ends of the tube is sealed by a seal band 2 and a holding mechanism 3, the covered guide pipe 1 is set to the center of the cylindrical mold 12 supported on a stand 6. A volute cylindrical body 13 expanded in diameter by definite pressure is arranged outside the pipe 1 and definite external force is applied to the entire periphery of the tube A expanded by gas pressure by the cylindrical body 13. By this constitution, unbalanced expansion can be eliminated and a tube shape is finished into a circular cross section by the restriction due to the mold 12.