Modeling the Quality of Glass Melting Processes

2010 ◽  
pp. 11-20 ◽  
Author(s):  
Adriaan Lankhorst ◽  
Andries Habraken ◽  
Mathi Rongen ◽  
Philip Simons ◽  
Ruud Beerkens
Keyword(s):  
Glass Melting

Online Inspection for Glass Fiber Forming

2006 ◽  
Vol 129 (1) ◽  
pp. 164-171 ◽  
Author(s):  
Paul P. Lin ◽  
Qing Guo ◽  
Xiaolong Li
Keyword(s):  
Glass Fiber ◽  
Fiber Diameter ◽  
Glass Melting ◽  
Noise Removal ◽  
Video Signals ◽  
Pixel Location ◽  
Inspection Process ◽  
Trained Neural Network ◽  
Online Inspection

Glass fiber forming is a complicated process in which many factors could affect the quality of fibers. The forming machine has many fiber-forming tubes that are close to each other and arranged in several layers. The closeness results in inadequate lighting and unwanted video signals. An anti-causal zero-phase filter was employed to remove noise with insignificant pixel location shift or distortion. In addition to the noise, the unwanted video signals constantly moving from one place to another also presented a challenge in image analysis. These signals were identified by a trained neural network that classified patterns. The unwanted signal identification through instant pattern classification made online inspection possible. During the fiber drawing process, the diameters of glass forming tubes and the profiles of glass melting cones were closely monitored and measured online in order to control the final fiber diameter. The accurate diameter measurements were accomplished by the noise removal along with a subpixel-resolution based edge detection technique. The results thus obtained for noise removal and unwanted video signals identification were quite good. The fiber diameter measurements were performed online, and the entire inspection process was automated with the aid of a programmable logic controller.

Refractories for Glass Making

MRS Bulletin ◽  
1989 ◽  
Vol 14 (11) ◽  
pp. 45-53 ◽  
Author(s):  
T.S. Busby
Keyword(s):  
High Performance ◽  
Glass Melting ◽  
Melting Rate ◽  
Steady Increase ◽  
Melting Temperatures ◽  
Number Of Factors ◽  
Fusion Cast ◽  
Glass Manufacture ◽  
Regenerative Furnace

Glass melting has changed very little in general principles since the earliest times, still being produced in fireclay pots or crucibles—even up to the present day. In Europe, experiments to melt glasses in tank furnaces began about 1700 A.D., but this became an important form of glass manufacture after Siemens introduced the regenerative furnace in 1870. This design was the basis for the development of modern furnaces and there is still a considerable similarity to the original.Until the late 1920s the glass contact refractories used in tank furnaces were based on fireclay or sandstone blocks. About this time important changes began when sillimanite and fusion-cast mullite refractories became available. However, because of the higher cost of fusion-cast refractories the introduction of these materials was delayed and they did not come into general use for lining the glass melting tank until the late 1940s.The high performance of tank furnaces today is related to a number of factors such as improved furnace design and regeneration, but the most significant has been an improved melting rate brought about by the use of higher temperatures. This has only been achievable as a result of the improved quality of fusion-cast and other refractory materials, such as those used in the furnace superstructure and regenerators. Garstang showed that there has been a steady increase in melting temperatures in the container glass industry. In data going back to 1920, there has been an increase from about 1300°C to some 1590°C. Bondarev showed that the increase in production achieved by using higher temperatures reduces the specific consumption of fuel.

An Instrument for Detecting Faults in Flat Glass

1968 ◽  
Vol 1 (2) ◽  
pp. 61-62 ◽  
Author(s):  
H. Benson ◽  
A. Rickaby
Keyword(s):  
Refractory Material ◽  
Production Line ◽  
Glass Melting ◽  
Flat Glass ◽  
Full Scale ◽  
Automatic Inspection ◽  
Melting Tank ◽  
Optimum Size ◽  
Float Process

One method of making flat glass is the float process, which produces an endless ribbon of the finished product. The width of the ribbon is approximately 10 feet. The glass contains faults such as bubbles and stones, which are small pieces of refractory material from the glass-melting tank. In order to assess the quality of the product and be able to cut it into pieces of optimum size, we need to know the number of faults and where they are. At present the glass is examined visually before the ribbon is cut, the inspectors marking each fault with a dab of ink so that after cutting, the pieces containing faults can easily be seen. To avoid the usual disadvantages of subjective examination, particularly since production speeds are continually rising, there is a need for some form of automatic inspection. An instrument to do this has been developed and, although not yet in full scale use, prototype trials on the production line have been carried out.

Analysis of quality parameters of fused cast AZS refractories for glass-making furnaces

2021 ◽  
pp. 3-9
Author(s):  
V. Ya. Dzyuzer
Keyword(s):  
Chemical Composition ◽  
Glass Phase ◽  
Glass Melting ◽  
Quality Parameters ◽  
Comprehensive Analysis ◽  
Cast Aluminum ◽  
Working Space ◽  
Zirconium Silicate ◽  
And Behavior

A comprehensive analysis of the quality parameters of fused-cast aluminum-zirconium-silicate (AZS) refractories for glass furnaces has been carried out. It is shown that the assessment of the quality of AZS refractories by the content of ZrO2 and density in them does not give an objective idea of their operational properties. Of fundamental importance are the chemical composition and behavior of the glass phase, which determine the volume and temperature of the onset of exudation. Among the most important conditions for obtaining high-quality AZS refractories, characterized by a melting volume of 2‒3 % of the glass phase and a melting start temperature above 1400 °C, include the oxidative melting technology and the content of impurities in the chemical composition of the refractory no more than 0,25‒0,30 %. The conditions for the service of AZS refractories in the melting basin and the working space of glass-melting furnaces are formulated. Their influence on the course of the exudation process, the corrosion resistance of refractories and the formation of defects in glass is shown. Ill. 2. Ref. 30. Tab. 4.

scholarly journals Silica crown refractory corrosion in glass melting furnaces

2011 ◽  
Vol 43 (3) ◽  
pp. 295-303 ◽  
Author(s):  
A. Balandis ◽  
D. Nizeviciene
Keyword(s):  
Glass Furnace ◽  
Glass Melting ◽  
Critical Parameters ◽  
Cyclic Change ◽  
High Quality ◽  
Refractory Corrosion ◽  
Glass Furnaces ◽  
Short Time ◽  
Initial Zone

The critical parameters of silica refractories, such as compressive strength, bulk, density, quantity of silica, microstructure and porosity were evaluated of unused and used bricks to line the crowns of glass furnaces, when the rate of corrosion of crowns were about 2 times greater. The change of these parameters, the chemical composition and formation of the microcracks in the used silica refractories material were studied. It was established that the short time at service of container glass furnace crown can be related to low quality of silica brick: high quantity of CaO and impurities, low quantity of silica, low quantity of silica, transferred to tridymite and cristobalite and formation of 5-10 ?m and more than 100 ?m cracks in the crown material. The main reason of corrosion high quality silica bricks used to line the crown of electrovacuum glass furnace is the multiple cyclic change of crown temperature at 1405 - 1430?C range in the initial zone of crown and at 1575 - 1605?C range in the zone of highest temperatures.

scholarly journals Analysis of fluid inclusions in vein quartz of the Fenkina-Lampi deposit by gas chromatography

2019 ◽  
Author(s):  
Евгения Светова ◽  
Светлана Шанина
Keyword(s):  
Gas Chromatography ◽  
High Temperature ◽  
Low Temperature ◽  
Fluid Inclusions ◽  
Glass Melting ◽  
Raw Material ◽  
High Temperature Region ◽  
Vein Quartz ◽  
High Quality

The composition and content of fluid inclusions in the main structural and technological types of vein quartz of the Fenkina-Lampi deposit were studied by gas chromatography. It is shown that H2O dominates (90–99%) in the gases composition released from quartz under heating to 1000°C, CO2, CO, N2 and hydrocarbon compounds contents are much less. Quartz is characterized by high gassing in the high-temperature region (600–1000°C) comparable to gassing in the low-temperature interval (100–600°C), which is a negative indicator of the quality of quartz as a raw material for high-quality glass melting. It is necessary to develop a special purification technology for this quartz, which will take into account the features of its saturation with gas-liquid inclusions.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

Lithography below 100 nm

1983 ◽  
Vol 41 ◽  
pp. 96-99
Author(s):  
L. D. Jackel
Keyword(s):  
Spatial Distribution ◽  
Electron Beam ◽  
Electron Scattering ◽  
Electron Beam Lithography ◽  
Substrate Material ◽  
Local Electron ◽  
Electron Dose ◽  
Positive Resist ◽  
Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

Sign in / Sign up

Export Citation Format

Share Document