9 results
Search Results
Now showing 1 - 9 of 9
- ItemGlassy phase segregation from AZS blocks(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2005) Fleischmann, Bernhard[no abstract available]
- ItemÖfen zur vollelektrischen Schmelze von Glas in Deutschland(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1994) Fleischmann, BernhardDie HVG verschickte im November 1993 einen Fragebogen an alle Betreiber von vollelektrischen Wannen in Deutschland mit einem Durchsatz von mehr als 10 t/d. 24 ausgefüllte Fragebögen wurden der HVG bis zum April 1994 zurückgesandt. Auch 6 vollelektrische Öfen von Nichtmitgliedern sind in die Auswertung mit aufgenommen. Ausgewertet wurden die Wannengröße (Durchmesser und Badtiefe), Art und Material der Heizelektroden, Gemengeeinlage, Gesamtscherbenanteil, Glasart und gefertigtes Erzeugnis, Schmelzleistung und spezifischer Wärmeverbrauch. In 8 Wannen wird Borosilicatglas erschmolzen, in 6 Kalk-Natronsilicatglas, in 4 Bleikristall- und in 2 Kristallglas, in 2 weiteren C-Glas und in einer Opalglas. Gefertigt werden Glasbehälter, Rohre, Wirtschaftsglas, Fasern, Streuscheiben und Beleuchtungsglas. Sowohl bei der Wannenfläche als auch bei der Badtiefe läßt sich in Abhängigkeit von der maximalen Tagestonnage eine gemeinsame Tendenz bei fast allen Öfen erkennen. Der spezifische Wärmeverbrauch sinkt mit steigendem Durchsatz bzw. größerem Wannenvolumen, da das Verhältnis von Oberfläche zu Wanneninhalt besser wird damit die Wandverluste anteilmäßig geringer werden. An 20 Wannen werden Molybdänelektroden und an 4 Wannen Zinnoxidelektroden eingesetzt. Diese Heizelektroden sind an 9 Wannen als Seiten- und Bodenelektroden eingebaut, an 7 Wannen als Seitenelektroden, an 5 Wannen als Bodenelektroden und an 3 Wannen als Topelektroden.
- ItemNon-destructive testing of refractories, especially AZS materials, with ultrasound, microwaves and γ-radiation(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1995) Fleischmann, BernhardIn principle four different methods (ultrasound, microwaves, γ-radiation and x-rays) are available for the non-destructive testing of refractories. Three of these methods, i. e. ultrasound, microwaves and γ-radiation, are in use by different producers of AZS materials to carry out the quaUty control of their products. This paper will compare the three methods on the basis of the physical properties, present the existing devices, and show the advantages as well as the hmits of the different methods. γ-radiography, the oldest method in use, has one main disadvantage, which is the requirement of protection against radioactive radiation. Furthermore, while cracks and cavities can be detected with this method, structural changes can not be monitored. Therefore, the ultrasonic method was developed that allows to detect variations of porosity and grain size as well as cracks and voids when the ultrasonic parameters are tuned as well as possible. As an alternative method testing with microwaves is also possible. This method, however, shows its best results when testing sintered refractory products with open porosity.
- ItemUltrasonic determination of the residual wall thickness of glass furnace refractories(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1997) Fleischmann, BernhardThe determination of the corrosion progress of refractory blocks on operating glass furnaces is of great interest to the glass industry. Several European glass research Institutes collaborated within the European SPRINT programme to develop an ultrasonic method of measuring the residual thickness of refractory blocks. The experience of the Hüttentechnische Vereinigung der Deutschen Glasindustrie and the TNO Institute of Applied Physics in the field of ultrasonic testing of materials as well as high-temperature applications of ultrasound were used to develop a device that was tested under laboratory conditions and in first industrial tests. After scaling up the equipment a number of industrial measurements were carried out on different furnace types in Europe. These tests showed that reliable results can be obtained with this device.
- ItemKonventionell beheizte Glasschmelzöfen für die Hohl- und Flachglasherstellung im deutschsprachigen Raum - Ergebnisse einer HVG-Umfrage - Teil 1. Beheizung, bauliche Merkmale, Schmelzleistung(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1997) Fleischmann, Bernhard[no abstract available]
- ItemKonventionell beheizte Glasschmelzöfen für die Hohl- und Flachglasherstellung im deutschsprachigen Raum - Ergebnisse einer HVG-Umfrage - Teil 2. Glasqualität und Energieverbrauch(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1997) Fleischmann, Bernhard[no abstract available]
- ItemCathodic electrochemical protection of molybdenum electrodes in an all-electric melter(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 1998) Fleischmann, Bernhard; Mergler, Kurt WilhelmDuring several research programmes the cathodic protection of molybdenum heating electrodes was tested step by step on an allelectric glass melting furnace over eight years. Starting with one pair at least, all 12 heating electrodes were superimposed with a negative direct voltage to reduce the corrosion of molybdenum. The molybdenum release of the electrodes could nearly be halved at the used furnace and with the glass melted. The molybdenum content of the glass was determined to compare the unprotected and the protected State, respectively, and to confirm the success of the cathodic protection.
- ItemBestimmung des Korrosionsfortschrittes an in Betrieb befindlichen Glasschmelzwannen(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2001) Fleischmann, Bernhard[no abstract available]
- ItemDetermination of the corrosion progress of zirconium oxide containing refractories based on the natural intrinsic gamma radiation of the material(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2001) Fleischmann, Bernhard; Baumann, Patrick; Mergler, Kurt WilhelmThe determination of the corrosion progress of refractory blocks is interesting for the operation of glass furnace tanks under safety and economic aspects. The measuring principle, based on the very small natural radiation of impurities of the zirconium raw materials for refractory production, has been known since the beginning of the seventies of the last century and could now be developed through improvements of measuring technology and sensors. Smaller changes to a laboratory test setup from medical technology were made both in the hardware and the software, to enable measurements of the intrinsie radiation of fused-cast AZS refractory materials in hot and dusty environment on glass melting furnaces during operation. Α measuring schedule was developed and calibrating measurements were carried out with blocks of different zirconia content. First practical tests were made on cold glass furnaces. The final adaptation of the equipment was done with measurements on operating glass furnaces. The measurements of the corrosion progress and/or the residual thickness of refractory blocks based on the natural intrinsic gamma radiation could be done with the expected accuracy and can be used to support the operator of glass melting tanks.