Transverse stretching and crystallizing machines TDOj

...for the production of polyester, polypropylene, polyamide as well as other plastic films with production speeds up to 500 m/min.

DORNIER TDOs are well known as very robust and easy to maintain machines with excellent airing system and different types of rail and clip systems for different applications. The returning rails are either within the oven or, for polyester or PA film production, outside the oven.

The patented DORNIER clips with ball bearings are suitable for all film thicknesses, from thin films (0.8 - 50 µm), on through the middle thickness range (50 - 125 µm) and on up to thick film production (up to 350 µm). One thing, however, which all DORNIER transverse stretching and heat setting machines have in common is the endless monorail clip guiding system guiding the clips from the inlet up to the end of the machine and back to the inlet, without any interruption. This system keeps the oil consumption for the clips as low as approx. 40 cm³ per day and machine, even at speeds up to 450 m/min.

Special treatment of the clip table and clip flaps can improve the friction value of these parts on the film. The ovens on all transverse stretching or heat setting machines are fitted with a base insulation. The complete oven is supported on ball bearings which allows heat expansion under controlled conditions (floating oven). The various oven zones are available with a length of 3 m or 4.5 m. Each zone is equipped with only one heater and one blower. The upper and lower nozzles are arranged in blocks allowing operators to move through an oven which simplifies maintenance work enormously.

This also allows removing film particles caused by a break very quickly. The DORNIER oven attains excellent air velocity distribution as well as temperature uniformity (1°C) with a temperature lowering device and can be delivered with 10 m width.

In case of a film break where film particles have to be removed from inside the oven, the oven can be entered within 1 minute after switching off the heating. The operator can pass through the oven after waiting another, approximate, 5 minutes. After the film particles have been removed (entering the oven) and the heating has been switched back on again, the temperature required to restart production can be reached after 15 minutes. DORNIER ovens can be heated with thermo oil, steam, electrically or these in combination. Direct gas-heated ovens are available for BOPP film production.