Haul off plant for extruded thermoplastic pipe with internal rib has guide rolls which align pipe at an angle to extrusion direction and induce a rotation of the pipe

摘要

A extruded pipe(1) with an integral internal rib(3) is fed at an angle into the haul off unit(11). Due to the angle of pipe entry the belt(13) of the haul-off exerts a tangential force onto the pipe wall(2) and causes the latter to rotate around its axis. The haul-off(11) is arranged at an acute angle to the extrusion direction so that pipe(1) enters the haul-off at not more than30degrees, preferably not more than15degrees. Pressure rolls(21) above the haul off are spring loaded to press the pipe against the conveying belt(13). A crossbeam supports the pressure rolls whose axes are parallel to the belt. Additional guide rolls(22) with axes at a right angle to the haul-off off conveyer are arranged at an acute angle to the extrusion direction. The guide rolls may lie on either side of the pipe. Guide rolls are mounted in the crossbeam so that they form a variable angle of not more than30degrees to the extrusion direction. Alternatively the crossbeam can be arranged at a variable angle of not more than30degrees to the extrusion direction. Crossbeam height above the conveyer can also be varied.