Pickling

High quality nozzles for your high quality process

The closer it comes to the final step of a production process the more important the direct result is. Hence, the pickling line has a decisive function in the entire production chain of steel.

Pickling Line

What you should keep in mind when planning

Material

The basis for all other following steps is to select an adequate material for the nozzles and the accessories. Also the life-time of these components depends on the material and the atmosphere they are used in. Keep in mind that the chemical resistance of the material depends very much on the specific operation conditions (such as temperature, acid concentration, residence time, mechanical stress, etc.).

Turbulence pickling

In the turbulence pickling section the nozzles have to offer a homogeneous liquid distribution over the entire material width. At the same time they are responsible for creating turbulence in the pickling liquid. The nozzle sprays have to force continuously the heated acid into the cracks of the scale layer on the strip. This is most important for an effective pickling and helps to accelerate the chemical process which will lead to an optimum capacity of the entire line. Flat jet nozzles could fulfill these demands in perfection. Whenever possible a staggered nozzle arrangement should be preferred to avoid any linear spray pattern on the strip. Furthermore, optimal overlapping of the adjacent sprays is a fundamental factor when defining the nozzle arrangement.

Rinsing

The rinsing section is absolutely decisive as it has to stop the chemical reaction and prevent over-pickling. An effective rinsing by an appropriate nozzle installation has a significant influence to the optimum result. Areas with a lower rinsing water density or even gaps in between the sprays could lead to severe quality issues. Therefore, an adequate nozzle selection and arrangement with an even liquid distribution is as important as good maintenance work.

Nozzle arrangement in pickling lineExample of a staggered nozzle arrangement

Blow-off

After leaving the rinsing section the water should be removed from the strip. Typically, nozzles for compressed air could manage this job. Especially, at the edges of the strip remaining rinsing water droplets have to be blown off. The multi-channel Whisperblast nozzles are especially designed to offer highest performance. Installed properly they are most effective. The air nozzles must cover the full range of the possible strip edges. Therefore, minimum and maximum strip width as well as the accuracy of the horizontal strip guidance has to be taken into account.

Pickling line blow-offStrip edge blow-off with multi-channel nozzles for compressed air

Spray headers

Precise nozzle sprays need to be installed accurately on precise spray headers. Complete spray headers could be manufactured by Lechler according to your drawings. Lechler could produce headers in material stainless steel as well as in plastics according to your specifications.

Spray headerSpray headers equipped with tongue type nozzles

Maintenance

As the nozzles and accessories are exposed to the rough operation conditions their state should be checked regularly. Especially the nozzles themselves are subject to wear, clogging or damage. A worn out nozzle could not fulfill the high functional demand anymore. An uneven overall liquid distribution and hence a non-uniform product surface could be the result. Worn out or clogged nozzles must be replaced by new ones in regular intervals to ensure optimum operation.

Maintenance pickling lineInfluence of clogged nozzles to the liquid distribution

Product overview

Düsen für Beizlinien

Precision Spray Nozzles for Pickling Lines

Nozzles for pickling lines require the highest quality to optimally support the processes in the production of your high-quality products.

More Technical data (pdf, 5.77 MB)

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