شیشه ماده شفافی است اما این شفافیت درجه خاصی دارد، شیشه های معمولی درجه مشخصی از شفافیت دارند اما شیشه فوق شفاف (ultra&Extra Clear Glass) بسیار شفاف تر از شیشه های معمولی می باشد. فرایند تولید و مواد خام اولیه تولید شیشه فوق شفاف کمی متفاوت تر از شیشه های شفاف معمولی است.
به طور کلی در مواد اولیه ساخت این شیشه ها سعی می شود از آهن کمی استفاده شود تا بازتاب نور به حداقل برسد، از اینرو به این شیشه ها Low-iron یا شیشه کم آهن نیز گفته می شود. هنگامی که چند لایه شیشه روی هم قرار می گیرند، درجه شفافیت شیشه نمایان تر می شود. در مواردی که از شیشه های دو یا چند جداره استفاده می شود و یا در مواردی که نیاز به استفاده از شیشه های لمینت دو یا چند لایه می باشد، اگر از شیشه های معمولی استفاده شود، مشاهده می شود که از وضوح و شفافیت شیشه بسیار کاسته می شود، در این موارد استفاده از شیشه فوق شفاف این مشکل را بر طرف می کند. در مواقعی که نیاز است که حداکثر نور خورشید از شیشه عبور کند مانند شیشه سلول های خورشیدی تولید برق، یا در مواقعی که لبه شیشه نمایان است، و یا در مواقعی که می خواهیم رنگ های واقعی محیط را ببینیم، شیشه فوق شفاف کاربرد فراوانی دارد. با افزودن پوشش های مخصوص روی شیشه می توان خاصیت ضد بازتاب دهندگی نیز به این شیشه ها افزود.
برچسبها: شیشه فوق شفاف
در سال های اخیر بحث و اختلاف نظر زیادی مبنی بر اینکه آیا شیشه سیمی به اندازه کافی ایمن می باشد یا خیر مطرح شده است. دلیل اصلی مطرح شدن این بحث ها، صدمات وارد شده به مردم در محل هایی است که شیشه سیمی در آنجا به کار گرفته شده است.
متداول ترین شیشه های سیمی ( شیشه های سیمدار)، همان هایی هستند که در درب و پنجره مدارس و مکان های عمومی نصب شده اند. گرچه شیشه سیمی مقاومت مناسبی در برابر انتقال شعله های آتش و دود دارد اما این شیشه ها نسبت به شیشه های حرارت دیده (سکوریت) یا لمینت مقاومت مناسبی دربرابر ضربه ندارند و ممکن است در هنگام ضربه خطرناک باشند. تحمل ضربه و ضد ضربه بودن عامل بسیار مهمی در مکان های فوق ازجمله مدارس، مهد کودک ها و مکان های تفریحی می باشد. برای سال های متمادی، تنها نوع شیشه ای که می توانست آزمون های ضد حریق و ضد ضربه را بگذراند، شیشه سیمی بوده است. با ورود شیشه های جدید که کارایی بهتری از شیشه سیمی هم در ضد حریق و هم ضد ضربه بودن دارند، بحث ناکارآمد بودن شیشه سیمی جدی تر شده است. متخصصان و منتقدان استفاده از شیشه سیمی ابراز می کنند که با وجود ورود شیشه های جدید و کارآمدتر دلیلی برای استفاده از شیشه های سیمی وجود ندارد و این شیشه ها را عامل بروز بسیار از صدمات می دانند. برخی از آنها پیشنهاد تغییر قوانین و آیین نامه ها را داده اند. از طرف دیگر، متخصصان طرفدار شیشه سیمی، نصب غیر اصولی و غیر ایمن را عامل بروز صدمات می دانند.
امروزه نسل های جدید از شیشه ضد حریق و شیشه ضد آتش وارد بازار شده اند که به خوبی تست های مربوط به شیشه های ضد حریق را گذرانده اند و درجه بالایی از ایمنی در برابر ضربه را هم دارا می باشند. به نظر می رسد شیشه های سیمی به دلیل ضعف در مقابل ضربه، به تدریج جای خود را به سایر انواع شیشه های ضد حریق بدهد
برچسبها: شیشه سیمی
شیشه سندبلاست
سند بلاست (مات کردن ) شیشه برای جلوگیری از دید یا ایجاد طرح ، نقش و نوشته بر روی شیشه مورد استفاده قرار می گیرد. شکلهای زیر چند نمونه طرح جالب سند بلاست را نشان می دهد:
ایجاد پخ توسط دستگاه گرند CNC و یا دستگاه لبه زنی صورت می گیرد. . ایجاد پخ با زاویه های مختلف و پخ تزیینی ، کاربرد شیشه را در زمینه ساخت پرژکتورها ،شیشه های رو میزی ، شیشه های دکوری و ... بسیار چشمگیر کرده است
شما میتوانید طرح های مورد نظر خود را با این روش روی شیشه پیاده سازی نمایید
شیشه رنگی شب تاب-شب نما
TINTED FLOAT
Tinted float is produced by adding metal oxides during float glass production. The most common colours are grey, bronze, green and blue. Apart from its function in an aesthetic sense, tinted float is primarily designed to reduce solar heat gain, UV and glare inside a building.
Tinted float glass achieves its performance by absorbing solar energy and so is sometimes referred to as heat absorbing glass. This heat absorbing quality means the glass is thermally stressed so some thicker or darker products may need to be toughened to avoid thermal stress breakage.
Tinted float can be processed into heat strengthened, toughened, laminated, curved glass and Insulating Glass Units. Tinted glass products are sourced from quality float glass manufacturers including Guardian, Glaverbel, Asahi and Pilkington.
Colour Selection
Refer to the colour bar on the right hand side of each Performance Diagram for a representation of the actual glass colour.
Grey Tint
Grey float is the traditional medium grey tinted glass characterised by its low light transmission and good control of solar heat and glare.
Manufactured in 4 - 12mm
Available in 4 - 12mm
Bronze Tint
Bronze float is the traditional medium bronze tinted glass designed to reduce solar heat and glare but providing a higher visible light transmittance than grey.
Manufactured in 4 - 12mm
Available in 5 - 10mm
Green Tint
Green float was initially used for automotive applications as it has very high light transmission. Modern green tints offer better solar performance with superior light transmittance to traditional grey and bronze tints.
Manufactured in 3 - 12mm
Available in 4, 5, 6 and 10mm
Blue Green Tint
Blue Green float is unique in that it is a cross between blue and green tint and offers an exceptional combination of high visible light transmission and low solar heat gain.
Manufactured in 6 and 10mm
Panasap Dark Blue
Panasap Dark Blue provides an alternative to grey and bronze tint with comparable solar control performance. Panasap Light Blue is ideal if a thicker glass is required with high light transmission, but is not readily available.
Light Blue Manufactured in 5 - 12mm
Dark Blue Manufactured in 3 - 12mm
Dark Blue Available in 6 and 10mm
1 BENDS AND CURVES
Terminology
To assist in understanding glass bends, the following terminology is used to describe the measurements and characteristics of bent or curved glass.
| Height | The straight edge length of a bend. |
| Girth | The distance around the circumference of the fence. |
| Depth | The distance between the apex of a bend and a line across the edges of a bend. |
| Radius | A line taken from the centre of a circle to the circumference of the circle. |
| Degree | The size of the segment of a circle expressed in degrees. |
| Tangent | A straight line coming off the arc of a curve |
| Chord | The straight distance between the edges of the curve. |
Ordering Requirements
- Provide all the measurements listed in the terminology if possible. If not all are available at least provide the radius, girth or chord and height measurements, and usual glass data: type, thickness, edgework, holes, notches, quantity, application and any special requirements.
The measurements must state if they are to the outside or the inside surface of the glass. - Provide a template of the radius or shape of the curve, and height measurement. Indicate if pattern measurement is to the inside or the outside of the glass. For shaped bends, provide a template of the shape and mark on the radius and all other details.
Glazing Notes
Special requirements apply to glazing curved glass, as the glass radius and the rebate radius are rarely the same. In addition the radius at the head can differ from that at the sill, it is critical that rebates are produced of sufficient size to accommodate all variances.
Do not wedge glaze. Wet seal only with silicone or other suitable sealant. If in doubt consult MetroGlassTech for glazing recommendations.
جواب:
Corrosion of refractory silica brick used to line the roof or “crown” of many glass-melting furnaces is a serious problem in furnaces using oxygen-fuel rather than air-fuel mixtures. In this work, we report equilibrium calculations that support a corrosion mechanism in which alkali hydroxide gas (NaOH or KOH), produced by reaction of water vapor in the combustion gas with the molten glass, reacts with the silica brick in the furnace crown to produce an alkali silicate liquid with a composition that depends on the temperature of the crown. Our reported calculations predict the variable-composition liquid-solution corrosion product phase as a function of key furnace variables. Critical thermodynamic data needed for the liquid corrosion product were generated using a modified associate species solution model and critical analysis of thermochemical information found in the literature for the 
and 
systems. Excellent agreement with reported 
and 
phase diagrams and with experimentally measured activities for 
and 
is achieved. The results of our current calculations are for temperatures between 1273 and 1973 K (1000-1700°C) under either air-fired or oxy-fired conditions, and are used to define a “critical temperature,” above which corrosion is not expected to occur for a given NaOH(g) or KOH(g) partial pressure. © 2001 The Electrochemical Society. All rights reserved
ادامه مطلب
The files below may be used to model the corrosion of various refractories used in glass melting furnaces. Those listed under "Silica corrosion" are designed to simulate corrosion of low-density silica bricks used in furnace crowns. The corrosive mechanism is assumed to be
-
-
M2O(in glass melt) + H2O(g, combustion gas)
2MOH(g), M = Na or K (1) 2MOH(gas) M2O(dissolved in liquid SiO2) + H2O(g, combustion gas) (2)
Files listed under "Alumina corrosion" are designed to simulate corrosion of high-purity alumina (either 
or 
) according to the reactions below. Similar reactions apply to alumina corrosion by KOH (although the temperature ranges differ). Details can be found in Ref. 2.
NaOH reaction with 
alumina:
T < 2158 K: 2 NaOH(g) + 9 Al2O3 2 NaAl9O14 + H2O(g, combustion gas)
T > 2158 K: 2 NaOH(g) Na2O(in Al2O3-rich liquid) + H2O(g, combustion gas)
-
NaOH reaction with
alumina: -
4 NaAl9O14 + 2 NaOH(g) 3 Na2Al12O19 + H2O(g) NaAl9O14 + 8 NaOH(g) 9 NaAlO2 + 4 H2O(g)
-
Silica Corrosion (See Ref. 1 for more details.)
-
Low-density silica corrosion by NaOH (Na-Ca-Si-O-C-H-N system) (File format: ChemSage)
-
Alumina Corrosion (See Ref. 2 for more details.)
-
Alumina refractory corrosion by NaOH (Na-Al-O-C-H-N system) (File format: ChemSage)Alumina refractory corrosion by KOH (K-Al-O-C-H-N system) (File format: ChemSage)
References:
1. M. D. Allendorf, K. E. Spear "Thermodynamic Analysis of Refractory Corrosion in Glass Melting Furnaces," J. Electrochem. Soc., 148, B59 (2001).
2. K. E. Spear, M. D. Allendorf "Thermodynamic Analysis of Alumina Refractory Corrosion by Sodium or Potassium Hydroxide in Glass Melting Furnaces," J. Electrochem. Soc., 149, B551-B559, 2002.
برچسبها: واكنش هاي خوردگي نسوزها در كوره هاي شيشه
Industry Facts and Figures
Flat glass is the material that goes into a variety of end-products such as windows and façades for buildings, windscreens and windows for transports, solar panels, but also in much lower quantities in many other applications such as furniture, electronics, etc.
Flat glass is the second largest sector of the glass industry in the European Union after container glass (bottles, jars, etc.). Flat glass represents around 30% of the total glass production. The sectors covers the production of float glass and rolled glass. Nowadays in the European Union, 97% of the flat glass is produced by means of the float process.
Production capacity and demand
In 2008, the sector reached a production capacity of 12.7 million tonnes of float glass from the 58 float tanks operating in the European Union and employed approximately 17,000 people in the manufacture of flat glass. On average, flat glass output annual growth is in the order of 2-3%.
Float installations are located across 16 countries of the European Union but three quarters of the EU production originates from Germany, France, Italy, Belgium, the UK, Spain and Poland.
However, demand for flat glass is particularly sensitive to economic cycles because of its high dependency on the building and automotive industries. During period of economic growth and high demand for flat glass, the annual growth is around 3% whereas during economic downturns or recessions the flat glass sector is hardly hit, as it is the case at the moment.
The economics of the flat glass sector
A float plant is highly capital intensive, typically costing around €70 million to €200 million depening on size, location and product complexity. Once operational, a float glass furnace is designed to operate continuously, 365 days per year, throughout its life of between 15 and 18 years. Float lines are normally capable of several “lifetimesf” ollowing major (€30 million to €50 million) repair or upgrade programmes.
The economics of the continuous-flow float operation require a high capacity utilisation rate – typically above 70% – before a plant becomes profitable. Energy and raw material costs are significant. Glass is relatively heavy, making distribution costs significant; they typically represent around 10% to 15% of total costs.
In most cases, transport costs make it uneconomic for float glass to travel long distances by land. Typically, 200 km would be seen as the norm, and 600 km as the economic limit for most products, though this varies between markets. It is possible for float glass to be economically transported along longer distances by sea provided additional road transportation is not required at both ends. This tends to favour float lines with local port access unless a local market is available for the line’s output. This is the reason why the vast majority of glass produced at the EU borders such as in Algeria, Egypt, Ukraine, etc. can be easily transported and sold in the European Union.
Key figures:
| 2nd | largest sector of the glass industries |
| 12 million tonnes | The EU float glass capacity production |
| 58 | float lines in the EU |
| 15 to 18 years | lifetime of a float line with continuous production 24 hours a day, 365 days a year |
| 17,000 people | number of employees of the flat glass sector in the UE27 |
| 70% | Utilization rate at which a float plant becomes profitable |
| 10 to 15% | distribution and transport costs |
| € 70 to €200 million | cost of a float line |
| €30 to €50 million | cost of an upgrade of a float line |
| 600 km | travel limit for float glass |
ادامه مطلب
يك محصول فرعى حاصل از كوره هاى قوس الكتريكى در جريان توليد آلياژهاى فروسيليس ميباشد. اين ماده با داشتن بيش از 90 درصد سيليس با حالت غير كريستالى و به شكل ذرات بى نهايت ريز با قطر متوسط 1/0 ميكرون شديدا پوزولانى است و براى استفاده به عنوان يك ماده سيمانى در بتن بسيار مناسب است.
استفاده از ميكروسيليس در بتن ریزی های مجاور سواحل دریاها به طور جدي مورد توجه مهندسين ساختمان قرار گرفته است. به دليل خصوصيات بارز پوزولاني ميكروسيليس، استفاده از آن جهت بهبود خواص مكانيكي و افزايش دوام بتن در كشور هاي پيشرفته رو به افزايش است.
موارد مصرف:
در بتن ريزى هاي مربـوط به ساخت اسكله هاى دريائى، شمعـها، سـتونها و قطـعات پـيش ساخته، فونداسيون ماشين آلات و كليه سازه هاى بتنى كه در معرض حملات شيميايى بويژه يون كلر و سولفاتها قرار دارند.
میکروسیلیس در حال حاضربه عنوان یکی از بهترین مواد افزودنی معدنی بتن شناخته می شود و اضافه کردن آن به مخلوط باعث کاهش نفوذ پذیري و در نتیجه افزایش دوام بتن می شود
مزايا:
- افزايش چشمگير مقاومتهاى مكانيكى بتن
- كاهش نفوذپذيرى بتن
- كاهش تحرك يون كلر
- جلوگيرى از خوردگى آرماتور در بتن هاى مسلح
روش و ميزان مصرف :
ميكروسيليس مانند سيمان هنگام ساخت بتن به آن اضافه ميشود. ميزان مصرف بهينه آن 10 الى 15 درصد وزن سيمان مصرفى است كه به همان ميزان ميتوان از مقدار سيمان مصرفى کم کرد .
امروزه توصیه اكثریت قریب به اتفاق
مهندسین مشاور صنعت ساختمان استفاده از دوده سیلیسی(Silica Fume) بهمراه
فوق روان كننده (Super Plasticizer) در زمان ساخت بتن میباشد . زیرا
آزمایشات علمی نشان داده اند كه وجود دوده سیلیس بمیران 7% وزن سیمان در
بتن به نحو چشمگیری از نفوذ یون كلر جلوگیری می كند. استفاده از دوده
سیلیس بهمراه فوق روان كننده در بتن كه بصورت پودر بسیار ریز (کمتر از 1/0
میکرون) با جرم حجمی پائین میباشد ، مضراتی از قبیل عدم اختلاط كامل با
بتن، مشكلات انبارداری، حمل ونقل، پرت مصرف وهمچنین مشكلات زیست محیطی و
خطرات بهداشتی برای پرسنل محیط كار را به همراه دارد. مسائل و مشكلات فوق
الذكر و پژوهشهای متعاقب منجر به فرآوری و تولید ژل میكروسیلیس گردیده
درسال 1380 در ایران عرضه گردید.
Glossary Of Furnace Terms
| TERM | DESCRIPTION |
| Arch | The roof or crown constructed on a radius for different parts of the furnace. |
| Back wall (or Gable wall) | The section of wall above the soldier blocks at the furnace charging end. |
| Batch House | The building where the raw materials are delivered, stored, handled, weighed, mixed and transferred to the furnace batch storage hopper. |
| Batch | The mixture of raw materials to a given composition, ready for delivery to the furnace melting end. |
| Batch Hopper | The steel batch storage hopper located above the batch charger. |
| Batch Charger | A machine that introduces the batch into the furnace melting end. |
| Brace Bolt (or Jack Bolt) | Steel bolts that apply pressure to the outside face of the constructed furnace refractory structures to act against internal outward pressure. |
| Breast wall | The section of sidewall between the soldier block and the crown skewback. |
| Bracing Member | Steel members that brace the furnace refractory structure. |
| Buckstay | The vertical structural steelwork members positioned adjacent to the outside face of the furnace refractory structures to which refractory supporting steelwork members are fixed. |
| Burner Block | A refractory block with one main aperture through which the fossil fuel burners fire. |
| Burn out (or Thermal clean) | A method of cleaning out deposits blocked in the regenerator checkers (or packings) using heat. |
| Campaign | The working life of a tank furnace from the start of a new furnace construction to the shut-down of the furnace. |
| Casing | The steelwork case supporting the forehearth sub-structure refractory. |
| Channel | The sub-structure part of the forehearth that carries the molten glass from the distributor (working end) of the furnace to the spout. |
| Checkers (or Packings) | The refractory pieces installed in the regenerator chamber for the purpose of heat recovery. |
| Conditioning Zone | The part of the forehearth after the cooling zone(s) where the glass is brought to the required working temperature. |
| Continuous Tank Furnace | A furnace which produces glass on a continuous basis in which the level of the glass remains relatively constant due to the batch being fed continuously into the furnace, therefore, replacing the glass withdrawn. |
| Controlled Cool-down | The cool-down of a furnace from working temperature to ambient temperature under controlled conditions. |
| Cooling Zone | The part of a forehearth adjacent to the refiner (or distributor/working end) and before the conditioning zone. |
| Cross-Fired Furnace | A tank furnace with parallel pairs of ports for fuel and air positioned along the length of the melting end with the burner flames travelling across the width of the glass bath and at right angles to the direction of glass flow. |
| Crown | The roof part of selected furnace areas. |
| Cullet | Broken glass that is added to the batch for re-melting. |
| Factory Cullet (or In-house/Domestic) | Cullet that is obtained from the glass making process within the factory. |
| Flux-line (or Metal-line) | The level of the molten glass in the furnace. |
| Font | The casting cavity in a fused cast Alumina/Zirconia, Silica refractory block. |
| Foreign Cullet | Cullet produced and obtained from an outside source. |
| Cooling Zone | Part of the forehearth superstructure rear and mid sections. |
| Distributor (Refiner or Working End) | A section of the Tank Furnace to which glass is delivered from the throat and then directed to the forehearths. |
| Doghouse | A small vestibule section of the furnace at the batch charging position into which the batch is discharged into the furnace melting end. |
| Electric Boosting | An auxiliary method of adding heat to the glass of a fossil fuel fired tank furnace, by passing an electric current through the molten glass. |
| End-Fired Furnace | A tank furnace with the ports situated in the back wall of the melting end and the burner flames travelling in the direction of glass flow. |
| End-Port Furnace | A tank furnace with the ports for fuel and air situated in the back wall of the melting end. |
| Feeder | A mechanical piece of equipment for the function of delivering glass gobs to the forming machine. |
| Feeder Connection | The opening in the Refiner (Distributor or Working end) sub-structure wall to receive the channel of the forehearth leading to the feeder. |
| Feeder Opening | An opening in the Refiner (Distributor or Working end) sub-structure wall through which glass flows into the forehearth and towards the feeder. |
| Flux-Line (or Metal-Line) | The level of the molten glass surface throughout the areas of the Tank Furnace. |
| Forehearth | A section of the Tank Furnace leading from the Refiner (Distributor or Working End) from which glass is conditioned and directed to the feeder forming process. |
| Glass | An organic product of fusion that has cooled to a rigid condition without crystallising. |
| Glass Container | A general term used when describing glass bottles and jars. |
| Gob | An amount of hot glass delivered to the forming machine by the Feeder. |
| Grillage | The structural steelwork supporting the furnace bottom areas. |
| Heat up (or Pre-heat) of a Furnace | The increasing of temperature of a cold furnace to operating temperature under controlled conditions. |
| Hot End | The glass manufacturing areas applicable to hot glass, i.e. melting end, distributor (or working end) and forehearths. |
| Hot Spot | The melting end temperature zone of a tank furnace having the highest temperature. |
| Hot Spot | A thin refractory structure showing a glow condition on the external face caused by internal wear. |
| Jamb | The superstructure front sidewall of a furnace melting end port carrying the port crown load. |
| Mantle Block | A refractory block fitting in the gap between forehearth zones. |
| Melter (or Melting End) | The chamber of a tank furnace in which the glass batch is melted. |
| Melting | The thermal process by which the glass batch is completely converted into molten glass, free from undissolved batch. |
| Melting Area | The total glass surface area of the melting end, excluding the doghouse area. |
| Melting Temperature | The range of furnace temperatures within which glass melting takes place. |
| Metal | Molten glass |
| Orifice | An opening through which glass flows, generally referred to when relating to a feeder opening in the bottom of the spout formed by the orifice ring. |
| Orifice Ring (or Bushing) | The ring that forms the opening through which glass flows in the bottom of the feeder spout. |
| Patching | Placing refractory blocks and/or materials over or within existing refractory structure wear areas while the furnace is in operation. |
| Port | The opening in a furnace superstructure through which fuel or flame enters or exhaust gases escape. |
| Port Arch | The roof of a port. |
| Pull (or Load/Output) | The quantity or weight of glass delivered by a furnace in a given time, usually 24 hours. |
| Rake Block | The refractory block positioned above the melting end burner block and before the port floor top tile. |
| Raw Batch | A glass batch without cullet. |
| Raw Cullet | A total amount of cullet without any glass batch. |
| Recuperative Furnace | A furnace having a recuperator. |
| Recuperator | A continuous heat exchanger in which heat is conducted from the products of combustion to incoming combustion air. |
| Refiner (or Distributor/Working End) | A part of a tank furnace for the purpose of conditioning the glass and directing the glass to the forehearths. |
| Refining | The stage in the glass melting process at which the molten glass is made almost free from undissolved gases. |
| Regenerative Furnace | A furnace having regenerators. |
| Regenerator | A cyclic heat interchanger that alternately receives heat from the gaseous products of combustion and transfers heat to the combustion air before combustion. |
| Reversal | The process where the direction of fuel, combustion air flow and exhaust gases are reversed. |
| Rider Arch (or Bearer Arch) | One of a series of arches that support the checkers (or packings) in a regenerator. |
| Scum | A floating layer of unmelted material on the molten glass surface. |
| Seed | An extremely small gaseous inclusion in a glass product. |
| Sill block | The refractory block above the melting end soldier or sidewall block supporting the burner block assembly. |
| Skimmer Block | A refractory block that holds back glass surface impurities, positioned at the forehearth entry and adjacent to the refiner (distributor/working end) |
| Skewback | the refractory pieces at each end of a crown or arch. |
| Skewback Member | The structural steelwork member supporting the skewback. |
| Spout | A part of a feeder that carries the orifice, revolving tube, plunger, etc. |
| Spy Hole (or Peep/Sight hole) | A small opening in the superstructure of a tank furnace or walls of regenerators, recuperator and flues through which observations are made. |
| Sting-out | Hot air and/or flame exhausted through openings in the furnace superstructure due to positive pressure. |
| Stone | An imperfection/crystalline inclusion in a glass product. |
| Straight Throat | A throat with the bottom positioned at the same level as the tank furnace melting end bottom. |
| Sunken Throat | A throat with the bottom positioned below the level of the tank furnace melting end bottom. |
| Superstructure | The parts of a furnace above the soldier/sidewall blocks. |
| Tank Furnace | A furnace that is constructed from refractory blocks to form a bath in which glass is melted. |
| Tank Block (or Soldier block / Sidewall block) | A refractory block used in the construction of the furnace structure that forms part of the melting end and distributor (working end) bath. |
| Tap | The process of draining the furnace of glass under controlled conditions. |
| Teaser (or Furnaceman) | The worker or operative in direct charge of furnace operations, during glass production. |
| Throat | The submerged channel between the melting end and the refiner (or distributor/working end) through which glass passes. |
| Throat Cover Block | The top or roof blocks of the throat passage. |
| Throat Sleeper Block | The side blocks of the throat passage. |
| Thrust Member | A structural steelwork member supporting the end walls of a refractory structure adjacent to a crown or arch contour. |
| Tie-Rod (or Tie-Bar) | The steel bar spanning and securing a crown or arch or securing steelwork members at each side of a refractory structure. |
| Tuckstone | A block that is placed above the soldier (or side wall) blocks and beneath the breast walls of the melting end and refiner (or distributor/working end) |
| Tuckstone Member | The structural steelwork member supporting the tuckstones. |
| Water Box | A water-cooled metal box applied to the outside face of a refractory block or structure or inserted into the glass to prevent glass flow generally in a refiner (distributor/working end) or forehearth. |
| Water Cooling Coil | A water-cooled metal coil positioned adjacent to a refractory block or structure to cool the local air flow and/or chill glass seepage from a refractory block or block joint. |
| Working end | Refer to Refiner description. |
Online Glass Engineering
Whether you’re looking to simplify your workflow, create a more homogenous melt environment, reduce energy consumption or increase adaptability to meet individual customer demands, the answer always lies in process enhancements. Which is easier said than done. To make an informed decision, you need qualified information. When can you expect a return on your investment? What parameters need to be fine-tuned? What is the medium-term impact of switching from oil to gas?
Intelligent software is essential to optimize all parameters involved in the various glass production steps. Investing in a proprietary solution can be time-consuming and expensive. Now there is another way. Glass manufacturers have on-demand access to a Web-based analysis tool that allows them to quickly and easily analyze complex process parameters. Online Glass Engineering offers rich functionality to make sure you get your glass, ingredients and batch data just right.
This 24-hour Web-based tool incorporates all facets of the glass-making process from thermal engineering to operating data analysis. And SSL encryption ensures that all data and queries you enter are totally secure. In a nutshell, our vast glass knowledge base takes the guesswork out of glasswork.
Heat & Mass balances
With the experience on a large variety of furnaces it is possible to forecast possible variations mainly focusing on the fuel consumption, such as:
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Electricity vs. Fuel as well as fuel changes
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Batch and/or glass changes o Heat recovery modifications
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Production increase (with additional electricity or oxygen)
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Conversion from air fuel to oxy fuel combustion (or vice versa)
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Recuperator or regenerator repairs
All these forecasts are based on heat and mass balances according to the most common enunciation of the first law of thermodynamics, that the increase in the internal energy of a thermodynamic system is equal to the amount of heat energy added to the system minus the work done by the system on the surroundings. The overall heat and mass balance of any glass melting furnace can be described as
The accuracy of the forecast is much depending on the base case and the type of variation or forecast respectively, where the base case can be an existing furnace with given data or even a new furnace design with only assumptions.
Based on an existing furnace, knowing all input variables, a forecast is very accurate. The fundamental idea behind is that with the given parameters the overall losses, as described above, can be calculated very quickly without evaluating the furnace refractory conditions etc. in detail. Within a specific forecast these losses will not change significantly. Even when the given parameters are not 100% correct, the forecast or trend respectively will be very accurate anyhow.
All Oxy-Fuel
One of the most popular oxygen applications, all oxy-fuel-fired melting eliminates the need for a combustion air or heat-recovery device. This process is one of the most efficient ways of reducing nitrogen oxides (NOx) and particulate emissions from glass furnaces.
Chart: Energy consumption of air fuel and oxy fuel installations as a function of the flue gas and air preheating temperatures
The chart shows the energy consumption of different air fuel and oxy fuel installations as a function of the flue gas and air preheating temperatures i.e. a furnace with a flue gas temperature of 1480 °C and an air preheating temperature of 1000 °C saves 65% (100- 35) of the energy compared to a furnace with no air preheating. When this furnace would be converted to AOF we can count with another 9% (35-26) compared to the furnace with no air preheating or 26% compared to the case of air preheating of 1000 °C.
Cullet Ratio
It is well known that increasing the cullet ratio reduces the amount of energy required significantly. Assuming a furnace for 300 t/d of typical container glass, per 10% of cullet, the energy consumption can be reduced by about 4-5%.
Cullet Preheating
One way to reduce the energy consumption is to introduce cullet and/or batch preheating. Assuming the same furnace as above with a typical cullet ratio of 60%, per 100 °C, the energy consumption can be reduced by about 2-3%.
Water content in the batch
Water in the cullet is typically introduced to the batch to prevent from carry over with typical volumes of 2-3%. Per 1% of water less in the batch, the energy consumption can be reduced by about 1,5%.
False Air
False air is not wanted, but always involved. False air has a very important influence on the energy consumption. 1% less oxygen content in the flue gas results in 6,0% of energy savings. With Online Glass Engineering, glass factories are provided with a perfect program to execute various kinds of calculations any time, whenever needed or required to check profitability, potential of optimization or amortization of planned investments.
The variations are unlimited and allow the glass producer to determine the optimum solution tailored to his specific furnace (melting process).
Your Advantages
The Online Glass Engineering Program is an all-in-one solution. This means huge transparency for glass producers as all modules are mutually compatible. It is also available at any time and from any place. Highly favorable conditions make it the most economic way for glass producers to reduce costs and optimize processes. An experienced support team of glass engineers is also permanently available.
http://www.glassglobal.com/online-glass-engineering.html
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