Emulsion-Process-Monitor in metal working processes EPM II
Zusammenfassung der Projektergebnisse
In the BRAGECRIM project, an Emulsion-Process-Monitor device for continuous in-process control of metal working fluid (MWF) quality and stability has been derived and validated. The measurement principle is based on in-process detection of MWF fluid light absorption within a band of multiple wavelengths. The results indicate the feasibility of the technique to detect physical changes that can take place in metal working fluid emulsions, especially concerning the droplet size distribution and its relation with the emulsion stability and the destabilization process. In cooperation with the Brazilian partners from USP analysis of emulsion flow behaviour around the sensor geometry have been carried out showing that no significant droplet separation processes may occur due to the flow pattern around the sensor that may have an impact on the sensor performance. The simulations were validated with experimental studies in model flow channels and as well as in metal working machines. Based on these results, a prototype for the implementation of the EPM device into the fluid cycle of a metal working machine has been constructed. A cleaning nozzle arrangement was installed in the EPM prototype to prevent and detach biological films from the sensor. Numerical inversion techniques for the detected turbidimetric spectra have been evaluated identifying the application limits of the inversion algorithms. The best performing algorithms were used to evaluate the UV-Vis Spectroscopy as measurement technique of the EPM device with other conventionally applied measurement techniques. The Brazilian cooperation partners from the USP developed a neural network (NN) model based evaluation procedure for the absorption spectra. Inversion and NN data treatment have been successfully compared for suspension and emulsion systems. The EPM device applied within stability experiments of conventional and “green” MWF; thus, identifying a characteristic salt concentration for MWF destabilization. The thermal oxidation process was investigated for MWF model components quantifying the degeneration process. The EPM device has been used to monitor the behaviour of commercial MWF applied in machining processes within their usage during several weeks. At the start of the machining operation, the MWF droplet size was small and the corresponding wavelength exponent high. The droplet size of the MWF emulsion increased over time, whereas the evaluated wavelength exponent from measurements decreased in a corresponding manner. The EPM device was successfully applied as a new in-situ measurement technique for emulsions applied in MWF operations in machining processes. It was possible to monitor online the MWF quality in terms of a change of the disperse state of the liquid-liquid emulsion system.
Projektbezogene Publikationen (Auswahl)
- Emulsions-Prozess-Monitor für den Einsatz in der Metallverarbeitung (Kühlschmierstoffe), Chemie Ingenieur Technik, 82 (2010), 1421
Glasse, B.; Fritsching, U.
- Multiwavelength- Spectroscopy as a novel Approach for the Quality management of Metal Working Fluids, Tribologie und Schmierungstechnik, 4 (2011), 10-13
Glasse, B.; Fritsching, U.; Koch, T.; de Paiva, J.L., Guardani, R.
- Turbidimetric spectroscopy for the evaluation of metal working fluids stability, Tribology Transactions, 55 (2012) 2, 237- 244
Glasse, B.; Fritsching, U.; Koch, T.; de Paiva, J.L., Guardani, R.
(Siehe online unter https://doi.org/10.1080/10402004.2011.653871) - Wiederherstellung einer Emulsions- Tropfenverteilung aus dem Online-Trübungsspektrum mittels numerischer inverser Methoden, Chemie-Ingenieur-Technik, 84 (2012) 8, 1376
Glasse, B.; Fritsching, U.; Guardani, R.
- Analysis of the stability of metal working fluid emulsions by turbidity spectra. Chemical Engineering Technology, 36(7), (2013), 1202-1208
Glasse, B.; Assenhaimer, C.; Guardani, R.; Fritsching, U.
(Siehe online unter https://doi.org/10.1002/ceat.201200590) - Refractive indices of metal working fluid emulsion components, Measurement Science and Technology 25(3), (2014), 035205
Glasse, B.; Zerwas, A.; Guardani, R.; Fritsching, U.
(Siehe online unter https://doi.org/10.1088/0957-0233/25/3/035205) - Turbidimetry for the stability evaluation of emulsions used in machining industry. Canadian Journal of Chemical Engineering, 92(2), (2014), 324-329
Glasse, B., Assenhaimer, C., Guardani, R., Fritsching, U.
(Siehe online unter https://doi.org/10.1002/cjce.21930) - Use of a spectroscopic sensor to monitor droplet size distribution in emulsions using neural networks. Canadian Journal of Chemical Engineering, 92(2), (2014) 318-323
Assenhaimer, C. ; Machado, L. J. ; Glasse, B.; Fritsching, U.; Guardani, R.
(Siehe online unter https://doi.org/10.1002/cjce.21861)
