Corrosion Protection of Semi-Finished Products - Process Monitoring of the Oil-to-Solvent Ratio

Relevant for semi-finished products in metal industry, steel, aluminium, copper and other metals

Corrosion bath monitoring

The inline viscosity sensor provides continuous slurry measurement. A viscosity range is defined for the slurry in the adjustment-vessel. If the actual dynamic viscosity value exceeds the limit for a specific period of time, stabilizer is added via a dosage pump to instantTo protect semi-finished products against corrosive attacks, it is necessary to cover them with a protection fluid existing of oil in an organic solvent mixture. After the evaporation of the solvent the oil remains as a clear corrosion-preventive film providing displacement of moisture. The continuous treatment of products implicates a shift of the oil-to-solvent ratio in the fluid.  Hence the wetting of the products shows various layer thicknesses during operation and the protection against corrosion is not on the same quality level.

Oil in solvent monitoring

The density sensors of the L-Dens series are highly efficient process instruments which take exactly this problem into account. They monitor the composition of the fluid continuously. Customer specific oil to solvent ratio can be monitored and thereby a constant high quality of the protective film is guaranteed. In addition, the consumption of the mostly expensive oils is reduced to a minimum.

Process density sensor L-Dens 3300

The process density sensor L-Dens 3300 from Anton Paar continuously displays the concentration of the oil in solvent. This measurement allows 24-hour monitoring of any bath. Furthermore maintenance free construction allows operating times for many years. These benefits are combined with high accuracy, robust design and cost efficiency. Due to the reduced consumption of oil the payback time for the sensor is quite short.


  • Constant quality monitoring
  • Optimizing oil consumption
  • Easy to integrate
  • Stable results

Learn more about the L-Dens 3300



L-Dens 3300 version SST


Measuring range: 500 - 2000 kg/m³
Process temp. range: 10 to 80 °C
Ambient temp. range: +10 to +40 °C
Process pressure: max. 16 bar (abs.)
Accuracy in adjusted range: 1 kg/m3

Measuring range

Sample concentration: customer specific
Sample temperature: customer specific

Other relevant instruments

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