Water dosing for sand conditioning plants
The task:
Uniform moisture in the mould material is an important criterion for avoiding a large number of quality assurance problems. Due to the different stresses and processes, however, used sand is subject to considerable moisture and temperature fluctuations before it is mixed. The objective of a reliable moisture measuring and control system which operates with reproducible results is that
used sand is uniformly moistened under recipe control and temperature effects are compensated.
Approach:
Moisture and temperature are measured continuously during dosing. Average values are determined and, when dosing has finished, the remaining water requirement is established by offsetting the specified recipe value.
This makes it possible quickly to determine the water required in the sand before mixing starts.
Solution:
A moisture electrode and a temperature electrode are installed for each discharge belt of the used sand bunkers. By measuring the moisture, the amount of water required to be added to achieve the required value is determined. The temperature specifies the amount of water required to compensate evaporation. The water can be injected when the batch is started. The mixer is not important in this respect for there is no need to instal a measuring device in the mixer. The moisture measuring electrode is self-cleaning in order to avoid the typical contamination effect.
Advantages: