A supply of continuous thin wall tubing which is drawn by a pair of opposed conveyor belts frictionally engaging the outside surfaces of the tubing first through a tube straightening device before the tube walls become engaged with the aforesaid conveyor belts so that straightened tubing is always subjected...http://www.google.es/patents/US6494353?utm_source=gb-gplus-sharePatente US6494353 - Tube feeding apparatus
