This book has been compiled as a training and reference document for g. The edge zone is defined by the area that is 1116 in form the edge. Zone a is the main zone and makes up 80 percent of the glass. Schenks glassinspect for float glass inspection is an inline inspection solution for quality assurance and process control for float and down draw glass manufacturing. The graphic shows the analysis of a certain bubble. Is a defect where a small ridge of glass has been formedon the sealing surface of the finish3. Float glass can be pretty flat but there are variables in the manufacturing having no effect float flass when used for windows, aquariums, or glass doors that have profound effect when used to determine flatness in the range needed even in the laxest home. The book is concerned with defects that infringe the basic characteristic of glass as a homogenous material with a noncrystalline structure. Glass defects originating from glass meltfused cast azs refractory interaction. Pdf an online defect classification method for float glass fabrication.
Float glass, sheet glass, automotive glass, architectural glass, display glass, sputtered glass, and patterned glass. Quality control is a crucial issue in a float glass factory, and defects existing in float glass can dramatically depress glass grade. An online defects inspection method for float glass. An online defects inspection method for float glass based on machine vision is presented in this paper, and a distributed online defect inspection system for float glass fabrication is realized. Details on astm standards for glass in the luxuryhome building industry. A special measuring system has been developed for the quality control of flat glass. Insulated glass a series of factors and physical rules define the characteristics of insulating glass as it is used in thermal insulation and solar protection applications. Pdf an online defects inspection method for float glass fabrication.
A measuring arm with several confocal sensors traverses the glass pane there. The ultimate objective is a semi quantitative model for glass defect prediction from fused cast azs in contact with tv screen glass melts to be able to choose conditions of lowest glass defect formation rates. The book is concerned with defects that infringe the basic characteristic of glass as a. Astm glass standards and the luxury building industry. In the float process, molten glass is delivered onto a pool of molten tin within an enclosed chamber and formed into a glass ribbon. Slight surface defects that originate in the process. This picture shows part of a tin bath related brownish defect found on the bottom surface of the float glass sheet. Since float glass is ordinarily sodalimesilica, the reference temperatures and behavior of this glass are used in the discussion below. As soon as a piece of glass is stable temperaturewise, it is then cut into specific shapes and patterns according to a customers needs. Pdf in float glass fabrication once defects are detected, recognition of the defect type is important for adjustment of the process conditions.
Especially in the hot end section of the furnace, volatile sno vaporizes from the tin bath and condenses on the colder parts of the superstructure and overhead equipment in the form of tin drops and cassiterite particles as a result of a snodisproportionation reaction 2sno. Flatman and john precisely voice my contentions about plate glass. This method gives the sheet uniform thickness and very flat surfaces. A continuous ribbon of glass moves out of the melting furnace and flows along the surface of an enclosed bath of molten tin. An area where glass has been broken off, but does not materially weaken the bottom of the body wall. Pdf an online defects inspection method for float glass. Dynamic architectural october 25, 2017 learning center its much more difficult to explain expectations around industry standards once the owner has already seen the glass and decided it is not acceptable to their personal expectations. Apegg glass container forming defects app overview. All previously scheduled classes, events, and programs are cancelled until further notice. Annealed glass can be cut, machined, drilled, edged and polished.
The optical properties of float glass surfaces like waviness, distortions or surface roughness are comparable with the former grinded and polished plates. Float glass, pattern and wire glass, thin glass, coated glass, laminated glass, mirror glass and other special products like lcd and tft display glass are manufactured on grenzebach equipment. Glass defects originating from glass meltfused cast azs. Feb 06, 2015 apegg have created this unique application which captures existing and new defect knowledge and bring the sharing of such information to the fingertips of the worlds glass container manufacturing. The coe of any given float glass will depend on which plant it came from, and who tests it which is typically not the glass manufacturer. For over twenty years, dark field technologies has been leading the glass surface inspection industry with a glass inspection system of new laser and camera inspection and glass coating defect detection technologies, including retroreflective laser systems for float glass inspection and telecentric lasers and cameras for lowe glass and display glass. In their study anderson and tushman defined the flat glass industry based on fourdigit sic codes. The key to successful float polishing is the 46cm diam tin lap. Guardian glasstime all about glass online glass handbook. In plate glass in the 1950s, called the floatglass method, results in an important. Float glass process an overview sciencedirect topics. The book is concerned with defects that infringethe basic characteristic of glass as a homogenous material with a noncrystalline structure. Glass decorated with streaks of two or more colors, resembling marble.
Dec 18, 2007 an online defects inspection method for float glass based on machine vision is presented in this paper, and a distributed online defect inspection system for float glass fabrication is realized. Born in cambodia in 1965, him lived from the age of three with the fear of war overflowing from neighboring vietnam and suffered through the u. And this is basically the principle on which the float glass manufacturing process is based. This method inspects defects through detecting the change of image gray levels caused by the difference in optic character between glass and defects. Polished wired glass onorm en 5724 glass in building basic soda lime silicate glass products. Because the surface of the molten tin is flat, so is the glass.
Holmes, inspection of float glass using a novel retroreflective laser scanning system, in optical science. Both online inspections by computer and manual inspection are also available to enhance the quality of glass and then it is ideal for customer line satisfaction. Flat glass inspection criteria per astm c 1036 06 abridged. A steel or marble table that is used to shape the glass. Float glass is manufactured by allowing the glass from the tank furnace to flow across a bath of molten tin in a. The glass pane is placed on a measuring table by a robot. Ribbon is held in chemically controlled atmosphere at a high enough. Method and apparatus for reducing tin defects in float.
What occurred was horrendous yet the endurance and tenacity of the people who were enslaved to survive incredible. Float glass inspection and measurement for highest quality. Within the glass world, the float glass process is frequently referred to as the pilkington process, since alastair pilkington is largely credited with the invention of float glass. This frit is compatible for our system 82 float glass glassy cuts and all float glass. Modification of float glass surfaces by ion exchange. Marbled glass was a venetian specialty from the 15th to 17th centuries, but it was also made in other times and places. Schenks focus at glasstec 2008 on solar glass inspection and enhanced defect classification for float glass. An online defect classification method for float glass. Cords see ream heavy strings incorporated in the sheet rather than on the surface. Floatglass not flat my experience practical machinist.
Significant investment in training, technology, equipment, business. By reading the zebra pattern across the ribbon, there is. Advances and processes in precision glass polishing. Ream see cords inclusions within the glass, or layers or strings of glass, that are not homogeneous with the. Introduction to glass technology 8 float process description. Aug 31, 2012 critical defects in glass bottles or containers1. The corning museum of glass is temporarily closed as a precautionary measure for public health and safety.
Cardinals float glass plants are designed to provide for the demands of our valued customers. Taytools 279205 three sheets 516 x 5 x 12 deal flat float plate glass with 7 sheets 3m tm lapping microfinishing film 414 x 11 for scary sharp sharpening system. Defected float glass is sent to the recycling process and used as a cullet in batching process. The float glass process, which was originally developed by pilkington brothers in 1959 haldimann et al. Top of the line residential window manufacturers rely on a constant supply of high quality float glass. Float glass also called flat glass that has not been heatstrengthened or tempered is annealed glass. Wintriss vision inspection systems detect continuous running glass surface defects 100% online or offline, and accurately provide product quality information. An open crack starting at the top of the finish and extendingdownward. During forming of float glass in a tin bath, tin residue can cling to the bottom of the glass ribbon, or drop onto the ribbon top side. Defects from all perspectives efficient detection of top and bottom tin defects. Glass defects originating from glass meltfused cast azs refractory. Visible glass defects are the kicker in the luxury custom home niche.
Glossary of flaws and defects glass and pottery sellers. Glass defects originating from glass meltfused cast azs refractory interaction citation for published version apa. I want to read more books on this subject now after reading when broken glass floats. The book argues that the nature of the industry should define the level of the analysis. General flaws and defects scratches light scratches scratches which do not score the surface of the item. The present invention provides a method of reducing tin defects in flat glass made by the float process.
Use of sulfur dioxide in chinese float glass production lines. The float glass is checked for any defect present in the glass. Sulfur dioxide gas is injected at the transitional roll desk directly toward the under surface of the float glass at temperatures. Industrial gases can be used to prevent reactions that are detrimental to the glass forming process. He is a recipient of the ohio governors award for emerging technology. Industrial gases for atmosphere control in glass forming. Float glass quality specifications for captured glazing quality assurance. More than 8085% of the global production of float glass is used in the construction industry glass for europe, 2015a. An online defects inspection method for float glass based on machine vision is presented in. Its much more difficult to explain expectations around. Glass is a common material in each persons life, e. Float polishing uses a rapidly rotating tin lap with aqueous polishing slurry of colloidal silicon oxide. Scratchdig refers to cosmetic defects found in glass from the manufacturing andor handling process. Drawn sheet glass onorm en 5725 glass in building basic soda lime silicate glass.
A piece of glass, usually very sharp, projecting inwardsjust inside the neck bore2. The batch floats on the glass melt and is heated by the radiation of the furnace crown and the flames from above and the transfer of heat from. Glass defects book this valuable book is written by the leadingexperts in the field of glass defectsand fills agap in the marketwhich has been essentially unaddressed until now. Float glass manufacturingproduction process ceramic ninja. Float glass is made by melting raw materials, consisting of sand, soda ash sodium carbonate, dolomite, limestone, and salt cake sodium sulphate. The raw materials, referred to as batch, are mixed and into a furnace at 1500c then blend together to form a large pool of molten glass.
A novel online float glass quality control method and a. The resultant label is highly wear and chemical resistant. Core channel top and bottom tin defects bubble stone float glass production line distortion channel. This valuable book is written by the leading experts in the field of glass defects and fills a gap in the market which has been essentially unaddressed until now. That means you can use this frit to create projects with float glass from your local glass shop. The float glass process is used to produce virtually all window glass as well as mirrors and other items that originate from flat glass. Industrial glass which today would be glass used in the automotive and construction industries was originally manufactured using a system known as float glass. Handbook glass handbook first edition rha0101 gjames h book cover 1800 12. At cardinal fg company, such quality is what you can expect our five u. The float glass process is also known as the pilkington process, named after the british glass manufacturer pilkington, which pioneered the technique in the 1950s at. Glass inspection standards wa wilson fabricates high quality tempered, insulated, and edged glass products. It isnt a simple product issue now, its an emotionallycharged issue revolving around expectations, reputations, and rescheduling stress you name it. The rejected glass pieces can then be returned to the furnace where they are remolten and used in a new production run.
An online defects inspection method for float glass fabrication based on machine vision. Float glass is a sheet of glass made by floating molten glass on a bed of molten metal, typically tin, although lead and various low melting point alloys were used in the past. Typical ream defects core channel top and bottom tin defects bubble stone float glass production line distortion channel defects from all perspectives efficient detection of top and bottom tin defects during forming of float glass in a tin bath, tin residue can cling to the bottom of the glass ribbon, or drop onto the ribbon top side. It detects defects, ribbon edges, knurl mark and distortion. No ones mind will be changed by karls book, but its a valuable report from the scene of an ongoing train wreck. Manual inspection in float glass quality control cannot catch up with the development of float glass industry, and automatic glass defect inspection has been a trend. The surface defect is viewed under optical microscope in transmitted light. Abrisa technologies standard metric for measuring such defects is based upon industry standards. Most of the commercially available float glasses are fairly similar to one another. Astm c 103616 standard specification for flat glass q3 glazing select. Esca analysis was carried out on glass surfaces which had been treated with snc1 4 vapour or with snc1 4 butyl acetate spray at temperatures of 450650.
Drummond, iii, is a professor at the ohio state universitys department of materials science and engineering, columbus, ohio. Quality control is a crucial issue in a float glass factory, and defects existing in float. From the composition of the gases in the bubble, but also from its size, distribution in the product, intensity and internal pressure, it is possible to identify possible source of such defect. James group is the most comprehensive and technologically advanced processor of glass in the asia pacific region. Float glass onorm en 5723 glass in building basic soda lime silicate glass products.
Top surface defects such as cassiterite particles sno 2 and tin drops, are an indirect result of an oxidation process. Marker and cutter tools allow cutting the float glass according to detected defect information, leaving out areas that have too many or too severe defects. Other materials have been tried with varying degrees of. This is done by revisiting the flat glass industry study, on which anderson and tushmans 1990 dominant design model is partly based. This book provided a very real, raw insight into the travails of this nation and the terrible suffering of its people. Equipment used for comparative standards have to be of known accuracy.
O 2, n 2, co 2, so 2, ar, h, cos, h 2 s, co, h 2, h 2 o. Manual inspection in an online defects inspection method for float glass based on machine vision is presented in this paper, and a distributed online defect inspection system for float glass fabrication is realized. Defects marker with traversing unit glass shee tshee cutter glass section with defects typical ream defects displaying defects in the visualization software top and bottom tin defects float glass production line efficient detection of top and bottom tin defects during forming of float glass in a tin bath, tin residue can cling to the bottom of. Bradley 781018300 rollformed channel frame float glass mirror, 18 width x 30 height. Use of sulfur dioxide in chinese floatglass production lines. Annealing float glass is the process of controlled cooling to prevent residual stress in the glass and is an inherent operation of the float glass manufacturing process. In order to improve quality of float glass and quality grade division, it needs inline automatic detection for float glass. In the float glass process, the ingredients silica, lime, soda, etc. Most float glass is sodalime glass, although relatively minor quantities of specialty borosilicate and flat panel display glass are also produced using the float glass process. An online defect classification method for float glass fabrication. Research on inline glass defect inspection technology.
Growing up under the khmer rouge him, chanrithy on. Two forms of stannic tin were identified, one assigned to sno 2 and the other to sn in association with one or more of the glass elements. Flaws and defects in pottery or glass the purpose of this glossary is to provide buyers and sellers with a common language for the condition of glass or pottery items. For example, inerting the tin bath during float glass manufacturing with nitrogenhydrogen blends can help prevent the formation of glass defects and protect the chambersequipment in which the glass is formed. Sep 06, 2016 the glass has no wave or distortion and is now the standard method for glass production. Bottom plate parting line where the blow mold and bottom plate join there is a.
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