given for another subject-matter by
A. Kucera
could be right here too as a colour retention means

Blasluft could also be blast air but IMO not in the above case.

Actually I´m not sure what the Wendestange is supposed to be, but forced air would be my guess... MJ

Here are two examples where blow-off air is used in painting/coating operations.
HTH!

Air Knife Applications
- Air blow-off systems have become very important because of the following
influences:Reduced solvent use in coatings, causing longer cure times. ...
www.turbotech.thomasregister.com/ olc/turbotech/turbo2.htm - 17k

Industrial Air Blow Off System
We supply high penetration blow-off air systems, process air-knife air guns,air-knves,air-knife
systems,air nozzles,industrial process air knives, air canons ...
nis-co.com/6/Index.html - 80k

If you application is about blown film extrusion:

The special geometry of the turner bars as well as the special hole pattern of the turner bars are the prerequisite for completely non-contact reversal of the film . Compared with the normal turner bars, the film is lifted completely clear of the stationery turner bar and is reversed with a significantly larger air cushion in this system.


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Note added at 2002-12-01 10:30:50 (GMT)
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Windestangen are also used on web printing machines, which would explain the bit about \'abschmieren von Farbe\', as the air cushion ensures a non-contact reversal or deflection of the web after printing.

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Note added at 2002-12-01 10:35:44 (GMT)
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\'W*E*ndestangen\', of course.

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Note added at 2002-12-01 10:40:39 (GMT)
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See http://www.dri-tec.com/turnbar.html for an excellent desciption

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