United States. Bureau of Mines. Abrasive materials by Gordon T Austin. Advanced materials by Charles A Sorrell.
Dear readers! Our articles talk about typical ways to solve the issue of renting industrial premises, but each case is unique.
If you want to know how to solve your particular problem, please contact the online consultant form on the right or call the numbers on the website. It is fast and free!
Enameling CeramicsVIDEO ON THE TOPIC: Basic Enameling Demonstration with Averill Shepps
Jonathan P. Hellerstein, Joel Bender, John G. Hadley and Charles M. Interestingly, not only do most of these sectors have roots in antiquity, but they also share a number of common general processes. For example, all are fundamentally based on the use of naturally occurring raw materials in powder or fine particulate form which are transformed by heat into the desired products.
Therefore, despite the range of processes and products encompassed in this group, these common processes allow a common overview of potential health hazards associated with these industries. Since the various manufacturing sectors are composed of both small, fragmented segments e.
There are common safety and health hazards encountered in manufacturing of products in these business sectors. The hazards and control measures are discussed in other sections of the Encyclopaedia. Process-specific hazards are discussed in the individual sections of this chapter.
Most of the industrial manufacturing processes receive dry solid raw materials in bulk form or individual bags. Bulk solid raw materials are unloaded from hopper rail cars or over-the-road trucks into bins, hoppers or mixers by gravity, pneumatic transfer lines, screw conveyors, bucket conveyors or other mechanical transfer.
Pallets of bagged raw materials 20 to 50 kg or large bulk fabric bag containers 0. Individual bags or raw materials are removed from pallets manually or with powered lift assists. Bagged raw materials are typically charged into a bag dumping station or directly into storage hoppers or scale hoppers. Potential safety and health hazards associated with the solid raw material unloading, handling and transfer processes include:. Pneumatic vibrators, compressors, valve actuators, mixing drive motors, blowers, and dust collectors are some major noise sources.
Exposures depend on composition of raw materials but may commonly include silica SiO 2 , clay, alumina, limestone, alkaline dusts, metal oxides, heavy metals and nuisance particulate. Manufacturing products in these business sectors involves drying, melting or firing processes in kilns or furnaces. Potential hazards presented from firing or melting processes include:. Back-up or stand-by fuel systems in-frequently used for natural gas curtailments can present similar fire or explosion concerns.
The working environment around furnaces or kilns can be extremely hot. Significant heat stress problems can occur when emergency repair work or routine maintenance is performed near or above firing or melting processes. Severe thermal burns can result from direct skin contact with hot surfaces or molten materials see figure Direct contact with high-voltage electric energy used for resistance heating to supplement fuel-fired processes presents an electrocution hazard and possible health concerns about exposure to electromagnetic fields EMF.
Strong magnetic and electric fields can potentially interfere with pacemakers and other implanted medical devices. Material-handling, fabrication and packaging processes differ to a large extent in this business sector, as do the size, shape and weights of products.
The high density of materials in this sector or bulky configurations present common material-handling hazards. Manual lifting and material handling in production, fabrication, packaging and warehousing in this industry accounts for many disabling injuries.
Injury reduction efforts are focusing on reducing manual lifting and material handling. For example, innovative packaging designs, robotics for stacking and palletizing finished products, and automatic guided transport vehicles for warehousing are starting to be used in select parts of this business sector to eliminate manual material handling and associated injuries.
Use of conveyors, manned lift assists e. Owens Corning. The use of robotics to eliminate manual material handling is playing a major role in prevention of ergonomic injuries. Robotics has reduced ergonomic stresses and severe laceration injuries that have been historically associated with material handling e. However, increased utilization of robotics and process automation introduces moving machinery and electric power hazards, which transforms the types of hazards and also transfers risks to other workers from production to maintenance workers.
Proper designs of electronic controls and logic sequencing, machine guards, total energy lockout practices and establishing safe operating and maintenance procedures are fundamental ways to control injuries to maintenance and production workers.
Numerous potential health and safety hazards are encountered during periodic major rebuilds or cold repairs to furnaces or kilns. A wide range of hazards associated with construction activities may be encountered. Examples include: ergonomic hazards with material handling e. Obsidian, for instance, is a naturally occurring combination of oxides fused by intense volcanic heat and vitrified made into a glass by rapid air cooling. Its opaque, black colour comes from the relatively high amounts of iron oxide it contains.
Its chemical durability and hardness compare favourably with many commercial glasses. Glass technology has evolved for 6, years, and some modern principles date back to ancient times. The origin of the first synthetic glasses is lost in antiquity and legend. Faience was made by the Egyptians, who molded figurines from sand SiO 2 , the most popular glass-forming oxide.
The copper oxide gave the article an appealing blue colour. A most important development in glass technology was the use of a blow pipe see figure From then onwards, there was a rapid development in the technique of manufacturing glass. Urban Glass. The first glass was coloured because of the presence of various impurities such as oxides of iron and chromium. Virtually colourless glass was first made some 1, years ago. At that time glass manufacturing was developing in Rome, and from there it moved to many other countries in Europe.
Many glass works were built in Venice, and an important development took place there. In the 13th century, many of the glass plants were moved from Venice to a nearby island, Murano. Murano is still a centre for the production of hand-made glass in Italy.
By the 16th century, glass was made all over Europe. Now Bohemian glass from the Czech Republic is well known for its beauty and glass plants in the United Kingdom and Ireland produce high-quality lead crystal glass tableware. Sweden is another country that is home to artistic glass crystalware production.
In North America the first manufacturing establishment of any sort was a glass factory. English settlers started to produce glass at the beginning of the 17th century at Jamestown, Virginia. Today glass is manufactured in most countries all over the world. Many products of glass are made in fully automatic processing lines. Although glass is one of the oldest materials, its properties are unique and not yet fully understood. The glass industry today is made up of several major market segments, which include the flat glass market, the consumer houseware market, the glass containers market, the optical glass industry and the scientific glassware market segment.
The optical and scientific glass markets tend to be very ordered and are dominated by one or two suppliers in most countries. These markets are also much lower in volume than the consumer-based markets. Each of these markets has developed over the years by innovations in specific glass technology or manufacturing advancements. The container industry, for example, was driven by the development of high-speed bottle-making machines developed in the early s.
The flat glass industry was significantly advanced by the development of the float glass process in the early s. Both of these segments are multi-billion-dollar businesses worldwide today. Depending upon the specific category, a variety of other materials compete for market share, including ceramics, metals and plastics.
Glass is an inorganic product of fusion which has cooled to a rigid condition without crystallizing. Glass is typically hard and brittle and has a conchoidal fracture.
Glass may be manufactured to be coloured, translucent or opaque by varying the dissolved amorphous or crystalline materials that are present. When glass is cooled from the hot molten state, it gradually increases in viscosity without crystallization over a wide temperature range, until it assumes its characteristic hard, brittle form.
Cooling is controlled to prevent crystallization, or high strain. While any compound which has these physical properties is theoretically a glass, most commercial glasses fall into three main types and have a wide range of chemical compositions. Soda-lime-silica glasses are the most important glasses in terms of quantity produced and variety of use, including almost all flat glass, containers, low-cost mass-produced domestic glassware and electric light bulbs.
Lead-potash-silica glasses contain a varying but often high proportion of lead oxide. Optical glass manufacture makes use of the high refractive index of this type of glass; hand-blown domestic and decorative glassware makes use of its ease of cutting and polishing; electrical and electronic applications takes advantage of its high electrical resistivity and radiation protection.
Borosilicate glasses have a low thermal expansion and are resistant to thermal shock, which makes them ideal for domestic oven and laboratory glassware and for glass fibre for plastic reinforcements.
A commercial glass batch consists of a mixture of several ingredients. However, the largest fraction of the batch is made up of from 4 to 6 ingredients, chosen from such materials as sand, limestone, dolomite, soda ash, borax, boric acid, feldspathic materials, lead and barium compounds. The remainder of the batch consists of several additional ingredients, chosen from a group of some 15 to 20 materials commonly referred to as minor ingredients.
These latter additions are added with a view to providing some specific function or quality, such as colour, which is to be realized during the glass preparation process. Figure The raw materials are weighed, mixed and, after the addition of broken glass cullet , taken to the furnace for melting.
Small pots of up to 2 tonnes capacity are still used for the melting of glass for hand-blown crystalware and special glasses required in small quantity. Several pots are heated together in a combustion chamber. In most modern manufacture, melting takes place in large regenerative, recuperative or electric furnaces built of refractory material and heated by oil, natural gas or electricity.
Electric boosting and cold top electric melting were commercialized and became extensively utilized globally in the late s and s. The driving force behind cold top electric melting was emission control, while electric boosting was generally used in order to improve glass quality and to increase throughput.
The most significant economic factors concerning the use of electricity for glass furnace melting are related to fossil fuel costs, the availability of various fuels, electricity costs, capital costs for equipment and so on. However, in many instances the prime reason for the use of electric melting or boosting is environmental control.
Various locations worldwide either already have or are expected soon to have environmental regulations that strictly restrict the discharge of various oxides or particulate matter in general. Thus, manufacturers in many locations face the possibility of either having to reduce glass melting throughputs, install baghouses or precipitators in order to handle waste flue gases or modify the melting process and include electric melting or boost.
The alternatives to such modification may in some cases be plant shutdowns. In addition, all types of glass are subjected to further controlled cooling annealing in a special oven or lehr.
Hellerstein, Joel Bender, John G. Hadley and Charles M. Typical body constituents 2. Manufacturing processes 3. Selected chemical additives 4. Refractory usage by industry in the USA 5.
Tin-based opacifiers in archaeological glass and ceramic glazes: a review and new perspectives
Jessica Elzea Kogel , Nikhil C. Trivedi , James M. Barker , Stanley T. Industrial Minerals and Rocks builds on the strengths of the earlier editions but adds significant new content—ensuring the continued relevance of this classic text. This widely read global reference tool is one of the most authoritative sources for timely information on industrial minerals and rocks, the markets they serve, and their multitude of uses. Changes in the global economy have greatly impacted the mining, processing, and marketing of industrial minerals. Additionally, the development of new technologies and a globalization of the customer base have driven fast-paced innovation in processing, packaging, transporting, and end use.
Enamels and glazes are used to cover metal and ceramics bodies. Whether lithium carbonate Li 2 CO 3 or spodumene is used, depends on the requirements of the application. Spodumene is a lithium aluminum silicate and already contains silicon oxide and aluminum oxide, which is a major component in glass. The best known application is the manufacture of glass-ceramic cooktops where no thermal expansion and thermal resistance is essential.
Tin-based opacification by tin oxide and lead-tin-oxide particles was used in glass production since the first millennium BC and in ceramic glazes since the eighth century AD. Opacification process is often characterised by significant amounts of tin oxide and lead oxide dispersed into glassy matrices or by identification of the opacifying particles by means of microstructural or micro- XRD analyses. The processes of opacification and manufacture are usually more difficult to establish from compositional and microstructural analyses because they leave little diagnostic traces. Tin-based opacifiers and colourants, namely lead-tin-oxide and tin oxide, were used to produce, respectively, yellow and white glass and glazes. They were also used as opacifiers in glass and glazes coloured by other metallic oxides, such as oxides of copper, manganese, and cobalt. In ceramic glazes, the technique marked a turning point in the development of West Asian and European ceramics e. Caiger-Smith The opacified glazes applied over the entire surface disguised the ceramics bodies and provided a smooth background onto which decorations could be applied. The use of tin-based opacifiers was preceded by that of antimony-based opacifiers i.
Cobalt oxides, and other complex cobalt compounds see Inorganic Pigments Consortium. Glass, porcelain, ceramics, paints, inks and enamelware have all been known to utilise cobalt compounds in the past and present to create a vivid cobalt blue colour. The unique combination of colour, solubility and stability, illuminate cobalt compounds as a powerful colouring agent in a variety of applications. The ability of cobalt-containing minerals to impart colour has been important for thousands of years going back to the times of the Egyptians and Persians.
Glass enamels and glass paints are especially designed for firing in a kiln and are available in a variety of colors. Take a glass capillary tube of about cm in length and seal one end of it. This Random Happens features a collaboration melting dr pepper soda bottles. They are used to join glass to other glasses, ceramics, or metals without thermally damaging the materials to be joined. Melting point range for tetracosane: degrees Celsius. It has a violent reaction during The lower gelling point and melting point when compared to Standard Agarose allows quick and thorough digestion during extraction procedures and easy in-gel manipulations. Melting Point Determination When doing a melting point determination, be careful to avoid contamination with impurities. Glass cant be "casted" like metal. PCL can be reheated and reshaped again and again. Since the temperature of the particles stayed well below the melting point of Ti, the only mechanism occurring was Solid State Sintering.
Inks and Pigments
This invention relates to methods of applying inorganic based luster pigments to a surface. More particularly, the invention relates to a method of applying the luster pigments to a vitreous surface in a manner wherein the luster pigment is fixed thereto without causing an adverse appearance effect. Background Art Luster pigments have a unique appearance. They have a pearlescent appearance which is pleasing to the eye. They are described in U. Patent Nos. The pigments are recommended for use in many formulations and have found wide acceptance in automotive paints, printing inks, plastic bottles, cosmetics and simulated pearls. Other luster pigments which are commercially available, though have not been as widely used, have an inorganic platelet-like particle such as glass with the metal oxide coating.
Rusportation and. Surface plant for large underground mine 6. Mining technology flowsheet 6. Naturally supported stopes room and pillar. Open sublevel stopes A drawing and B photograph. Summary and introduction. Scaling 7. Ground support types of sets photographs. Underground loading. Underground transportation 7.
Table of Contents
Jonathan P. Hellerstein, Joel Bender, John G. Hadley and Charles M. Interestingly, not only do most of these sectors have roots in antiquity, but they also share a number of common general processes.
Enamels and Ceramics
Enamel Art. Want to show some love for your favorite band?
Archaeological and Anthropological Sciences. Tin-based opacification by tin oxide and lead-tin-oxide particles was used in glass production since the first millennium BC and in ceramic glazes since the eighth century AD. Opacification process is often characterised by significant amounts of tin oxide and lead oxide dispersed into glassy matrices or by identification of the opacifying particles by means of microstructural or micro- XRD analyses.
This application is a division of application Ser. The present invention concerns firmly fixed decorative ceramic color layers applied to glass or glass ceramic substrates. Ceramic colors are often used to decorate glass and glass ceramics. They usually consist of one or several vitreous substances base enamel or vitrification and an admixture of one or several pigments coloring agents.