Important technical terms

Kolene pickling-plant
Extruded and also stretch reduced tubes, pipes and hollows have to be liberated from glass and scale. This is achieved with a procedure of the Kolene Corporation, which is patented in the USA. The Kolene bath approximately consists of: 63 % NaOH, 15 % KOH, 12 % NaNO3, 10 % NaCl and works at 480 - 500 C°. The duration of the treatment is approx. 10 - 15 min. Then the tubes, pipes and hollows are quenched in water and afterwards pickled in mixed acid, rinsed in water and dried. The complete cycle has to be repeated 2-3 times.