Nozzles speed up pickling

Pickling of carbon steel strip: New process increases pickling speed and/or reduces length of pickling lines

Nozzles speed up pickling

Assembly of a spray module at the pickling line entry; the pickling tanks are in the background.

At Metec, CMI UVK will introduce its newly developed spray modules for pickling steel strip. In these modules, the acidic pickling liquor removes the scale much more efficiently from the strip surface than in conventional turbulence pickling lines. Thus, carbon steel strip can now be pickled in markedly less time than before, and newly built pickling lines can be designed with a shorter length. Moreover, it will be possible to flexibly adapt the pickling parameters from coil to coil. As a further advantage, the process saves energy because the pickling liquor temperature can be lower.

The new, patent-pending technology consists of several nozzles arranged across the width of the strip. These nozzles spray the acid onto the strip surface from above and below with high impact. Alone by the impinging acid jet is a large part of the scale adhering to the strip removed.

Compared to conventional turbulence pickling, spray pickling achieves an equivalent surface quality in much less time. In laboratory tests, the pickling time, for example for „1.1231“ was reduced from 55 to 14 s, for „1.8159“ from 39 to 18 s and for IF steel from 33 to 10 s.

By combining spray pickling modules and pickling tanks in a specific way, this process opens up numerous new possibilities. The options range from the installation of just one spray module at the line entry through to a layout with several cascades of spray pickling modules and pickling tanks arranged in series. In all cases, the surface quality will be equal to or even better than that achieved in conventional turbulence pickling lines.

The length of newly built pickling lines can be reduced from more than 80 m – the typical length of conventional turbulence pickling lines – down to below 50 m. In other words, a 40 percent length reduction. This would cut the investment costs for a typical-size pickling line by several hundred thousand euros.

If the modernization target is to maximize the capacity while retaining the existing line length, the strip speed may be increased from, let“s say, 180 m/min to about 300 m/min through spray pickling.

With spray pickling, it is now also possible to vary the pressure of the frequency-controlled circulation pumps within wide ranges. This enables the pickling line to be set to optimal conditions for different steel grades in a very short time – even from one coil to the next.

The new process also makes it possible to pickle at lower temperatures than in the past, with the positive effect of saving costs on energy. Lowering the liquor temperature, for example from 90° C to 70° C, can save more than 20 percent of the energy costs.

CMI UVK at Metec (Düsseldorf, June 16 – 20, 2015):
Hall 05, booth D04

About CMI UVK GmbH
CMI UVK offers the full line of engineering and project management services for cleaning, degreasing and pickling solutions for strip, wire rod, tubes and pipes, as well as single parts:
– Pickling lines for carbon and stainless steel products
– Continuous and push-pull pickling lines
– Regeneration plants based on the fluidized bed and spray calcination principles
– Degreasing lines
– Waste water treatment plants for pickling lines
– Off-gas treatment plants

CMI UVK, based in Montabaur/Germany, belongs to the Belgian CMI Group and forms the Group“s centre of competence for the chemical surface treatment of steel strip.

Firmenkontakt
CMI UVK GmbH
Ingo Wohnig
Robert-Bosch-Straße 12
56410 Montabaur/Germany
+49.2602.9999-144
+49.2602.9999-596
ingo.wohnig@CMIgroupe.com
www.CMIgroupe.com

Pressekontakt
VIP-Kommunikation
Regina Reinhardt
Süsterfeldstraße 83
52072 Aachen / Germany
+49.241.89468-24
reinhardt@vip-kommunikation.de
www.vip-kommunikation.de