| 摘要 |
PURPOSE:To make it possible to insert a plastic tube in a tubular path without any trouble, by pulling in the plastic tube with a flat shape in the tubular path while molding and flat treatment of the plastic tube are continuously carried out at a construction site. CONSTITUTION:An extrusion-molded plastic tube 2 is flat-treated by means of flat-treating rolls 4 and 4 after passing through a cooling bath 3. This flat- treatment is carried out by softening the plastic tube 2 by heating. As the heat- softening means for the plastic tube 2, e.g., a means where a heater is built in the flat-treating rolls 4 and 4, and a means where steam is fed in an ejecting tube 5 from its rear end and ejected from an apex head 5a of the steam tube 5 into the plastic tube 2 can be cited. Fixing of a bung 7 and connection of a pulling rope 8 being drawn in the tubular path in advance are carried out with an apex of the plastic tube 2' after flat-treatment are carried out, and the flat plastic 2' is pulled in the tubular path a by pulling with the rope 8. |
