วันศุกร์ที่ 12 ตุลาคม พ.ศ. 2555

Aluminium


Aluminium ( /ˌæljuːˈmɪniəm/ al-ew-min-ee-əm) or aluminum (American English;  /əˈluːmɪnəm/ ə-loo-mi-nəm) is a chemical element in the boron group with symbol Al and atomic number 13. It is silvery white, and it is not soluble in water under normal circumstances.
Aluminium is the third most abundant element (after oxygen and silicon), and the most abundant metal, in the Earth's crust. It makes up about 8% by weight of the Earth's solid surface. Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is found combined in over 270 different minerals.[6] The chief ore of aluminium is bauxite.
Aluminium is remarkable for the metal's low density and for its ability to resist corrosion due to the phenomenon of passivation. Structural components made from aluminium and its alloys are vital to the aerospace industry and are important in other areas of transportation and structural materials. The most useful compounds of aluminium, at least on a weight basis, are the oxides and sulfates.
Despite its prevalence in the environment, aluminium salts are not known to be used by any form of life. In keeping with its pervasiveness, aluminium is well tolerated by plants and animals.[7] Owing to their prevalence, potential beneficial (or otherwise) biological roles of aluminium

วันพุธที่ 18 กรกฎาคม พ.ศ. 2555

Masonry heater


          A masonry heater (or masonary stove, ceramic stove, tile stove) is a device for warming an interior space by capturing the heat from periodic burning of fuel (usually wood), and then radiating the heat at a fairly constant temperature for a long period . The technology has existed in different forms: from the Roman hypocaust to the Austrian/German kachelofen. The hypocaust is a system for heating the floors and walls of buildings (especiallybaths) using the smoke and exhaust of a single fire. In Eastern and Northern Europe and North Asia, these kachelofens (or steinofens) evolved in many different forms and names: for example the Russian Stove/Fireplace (Russian: Русская печь), the Finnish Stove (in Finnish: pystyuuni or kaakeliuuni, "tile oven") and the Swedish Stove (in Swedish: kakelugn, "tile stove" or "contra-flow stove") associated with Carl Johan Cronstedt. The Chinese developed the same principle into their Kang bed-stove. The masonry heater has gained renewed domestic popularity recently because of its heating efficiency.


Thank for Info : http://en.wikipedia.org

Porcelain tile


          Porcelain tiles are ceramic tiles with a water absorption rate of less than 0.5 percent that are used to cover floors and walls. They can either be unglazed or glazed.
          The hardness of the tile is rated from zero to five according to the ASTM C1027 (or ISO 10545-7) test for surface abrasion resistance of glazed tile. This rating, (sometimes mistakenly called the PEI rating) determines the tiles suitability for various end use conditions.
          Large-scale production of porcelain tile is undertaken in many countries, with the major producers being China, Italy, Spain and Turkey. There are also countries undertaking small-scale production, such as Australia and strong growth in developing countries such as Brazil.
         Porcelain Tile is also a very common trend in tile installation. There are many different styles of porcelain tiles on the market and they have proved to outperform ceramic tile in durability and looks.
          It is important to note that the differences of the body of the porcelain tile, as it relates to ceramic tile, has caused many "job failures" of tile installations. Tile setters that are self trained and novices to the industry will often use cements or mastic to install the impervious body of the porcelain tile to a substrate only to have delamination occur rather quickly. Highly Modified cements are necessary for installation of this material due to the very qualities that make it such a durable long lasting decorative surface. Those specifications are determined by and dictated as industry standards by the Tile Council of America, and supported by the Tile Contractors Association.

Thank for Info : http://en.wikipedia.org

วันอาทิตย์ที่ 15 กรกฎาคม พ.ศ. 2555

High temperature insulation wool


          In the 1950s, the term “Refractory Ceramic Fibre” was coined for the aluminium silicate fibres developed at this time. On account of their chemical purity and resistance to high temperatures (classification temperature >1000 °C) as well as on the basis of their use in other applications, this definition was made to differentiate aluminium silicate wools from the conventional “mineral wools”. Because of the ambiguity of the term “ceramic” and the development of new materials for the high temperature range, the nomenclature was changed to High Temperature Insulation Wool (HTIW) at the end of the 1990s.
          Basically, there are two types of inorganic HTIW. In addition to the more commonly used amorphous HTIW (Alumino Silicate Wool ASW/RCF and Alkaline Earth Silicate Wool (AES)), Polycrystalline Wool (PCW) is also available. Owing to the costly production and limited availability compared to mineral wool, HTIW products are almost only used in industrial applications and processes up to 1800 °C.

Thank for Info : http://en.wikipedia.org

Silicon nitride


          Silicon nitride is a chemical compound of silicon and nitrogen. If powdered silicon is heated between 1300 °C and 1400 °C in an atmosphere of nitrogen, trisilicon tetranitride, Si3N4 is formed. The silicon sample weight increases progressively due to the chemical combination of silicon and nitrogen. Without an iron catalyst, the reaction is complete after several hours (~7), when no further weight increase due to nitrogen absorption (per gram of silicon) is detected. In addition to Si3N4, several other silicon nitride phases (with chemical formulas corresponding to varying degrees of nitridation/Si oxidation state) have been reported in the literature, for example, the gaseous disilicon mononitride (Si2N); silicon mononitride (SiN), and silicon sesquinitride (Si2N3), each of which are stoichiometric phases. As with other refractories, the products obtained in these high-temperature syntheses depends on the reaction conditions (e.g. time, temperature, and starting materials including the reactants and container materials), as well as the mode of purification. However, the existence of the sesquinitride has since come into question.
The Si3N4 phase is the most chemically inert (being decomposed by dilute HF and hot H2SO4). It is also the most thermodynamically stable of the silicon nitrides. Hence, Si3N4 is the most commercially important of the silicon nitrides and is generally understood as what is being referred to where the term "silicon nitride" is used.
          Silicon nitride (i.e. Si3N4) is a hard ceramic having high strength over a broad temperature range, moderate thermal conductivity, low coefficient of thermal expansion, moderately high elastic modulus, and unusually high fracture toughness for a ceramic. This combination of properties leads to excellent thermal shock resistance, ability to withstand high structural loads to high temperature, and superior wear resistance. Silicon nitride is mostly used in high-endurance and high-temperature applications, such as gas turbines, car engine parts, bearings and metal working and cutting tools. Silicon nitride bearings are used in the main engines of the NASA's Space shuttles. Thin silicon nitride films are a popular insulating layer in silicon-based electronics and silicon nitride cantilevers are the sensing parts of atomic force microscopes.

Thank for Info : http://en.wikipedia.org

วันอังคารที่ 10 กรกฎาคม พ.ศ. 2555

Refractory metals

          Refractory metals are a class of metals that are extraordinarily resistant to heat and wear. The expression is mostly used in the context of materials sciencemetallurgy and engineering. The definition of which elements belong to this group differs. The most common definition includes five elements: two of the fifth period (niobium andmolybdenum) and three of the sixth period (tantalumtungsten, and rhenium). They all share some properties, including a melting point above 2000 °C and high hardness at room temperature. They are chemically inert and have a relatively high density. Their high melting points make powder metallurgy the method of choice for fabricatingcomponents from these metals. Some of their applications include tools to work metals at high temperatures, wire filaments, casting molds, and chemical reaction vessels in corrosive environments. Partly due to the high melting point, refractory metals are stable against creep deformation to very high temperatures.


Thank for Info : http://en.wikipedia.org

Oil shale

Oil shale

          Oil shale, also known as kerogen shale, is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons called shale oil (not to be confused with tight oil—crude oil occurring naturally in shales) can be produced. Shale oil is a substitute for conventional crude oil; however, extracting shale oil from oil shale is more costly than the production of conventional crude oil both financially and in terms of its environmental impact. Deposits of oil shale occur around the world, including major deposits in the United States of America. Estimates of global deposits range from 2.8 to 3.3 trillion barrels (450×109 to 520×109 m3) of recoverable oil.
          Heating oil shale to a sufficiently high temperature causes the chemical process of pyrolysis to yield a vapor. Upon cooling the vapor, the liquid shale oil—an unconventional oil—is separated from combustible oil-shale gas (the term shale gas can also refer to gas occurring naturally in shales). Oil shale can also be burnt directly in furnaces as a low-grade fuel for power generation and district heating or used as a raw material in chemical and construction-materials processing.
          Oil shale gains attention as a potential abundant source of oil whenever the price of crude oil rises. At the same time, oil-shale mining and processing raise a number of environmental concerns, such as land use, waste disposal, water use, waste-water management, greenhouse-gas emissions and air pollution. Estonia and China have well-established oil shale industries, and Brazil, Germany, Russia also utilize oil shale.
          Oil shales differ from oil-bearing shales, shale deposits which contain petroleum (tight oil) that is sometimes produced from drilled wells. Examples of oil-bearing shales are the Bakken Formation, Pierre Shale, Niobrara Formation, and Eagle Ford Formation.

Thank for Info : http://en.wikipedia.org

วันอาทิตย์ที่ 8 กรกฎาคม พ.ศ. 2555

Thermal insulation

Thermal insulation
          Thermal insulation is the reduction of heat transfer between objects in thermal contact or in range of radiative influence. Heat transfer is the transfer of thermal energy between objects of differing temperature. The means to stem heat flow may be especially engineered methods or processes, as well as suitable static objects and materials.
Heat flow is an inevitable consequence of contact between objects of differing temperature. Thermal insulation provides a means to maintain a gradient of temperature, by providing a region of insulation in which heat flow is reduced or thermal radiation is reflected rather than absorbed.
          In building construction, insulating materials are assigned a quantitative measure of the insulating capability, called the R-value.
         In thermal engineering of insulating systems for ovens, reactors, and furnaces, thermal conductivity (K), product density and specific heat (C) are the key product characteristics, which influence insulating efficiency, such as acolodet insulating.
Low thermal conductivity (K) is analogous to high insulating capability (R).
          Aerogels, microporous silica and ceramic fiber insulation are three best performing insulators for applications between 200 Celsius and 2000 Celsius. Zirconia fibers have the lowest thermal conductivity of all ceramic fiber products and are used in applications up to 2000 Celsius.

Thank for Info : http://en.wikipedia.org

Filtration

Filtration


         Filtration is commonly the mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size and filter thickness). Filtration is also used to describe some biological processes, especially in water treatment and sewage treatment in which undesirable constituents are removed by absorption into a biological film grown on or in the filter medium.


Thank for Info : http://en.wikipedia.org

วันพฤหัสบดีที่ 5 กรกฎาคม พ.ศ. 2555

Furnace


          A furnace is a device used for heating. The name derives from Latin fornax, oven.
In American English and Canadian English, the term furnace on its own is generally used to describe household heating systems based on a central furnace (known either as a boiler or a heater in British English), and sometimes as a synonym for kiln, a device used in the production of ceramics. InBritish English the term furnace is used exclusively to mean industrial furnaces which are used for many things, such as the extraction of metal from ore(smelting) or in oil refineries and other chemical plants, for example as the heat source for fractional distillation columns.
          The term furnace can also refer to a direct fired heater, used in boiler applications in chemical industries or for providing heat to chemical reactions for processes like cracking, and is part of the standard English names for many metallurgical furnaces worldwide.
The heat energy to fuel a furnace may be supplied directly by fuel combustion, by electricity such as the electric arc furnace, or through induction heatingin induction furnaces.

Thank for Info : http://en.wikipedia.org

Plastic explosive


          Plastic explosive is a specialised form of explosive material. It is a soft and hand moldable solid material. Plastic explosives are properly known as putty explosives within the field of explosives engineering. Common plastic explosives include Semtex and C-4. Plastic explosives are especially suited for explosive demolition as they can be easily formed into the best shapes for cutting structural members and have a high enough velocity of detonation and density for metal cutting work. They are generally not used for ordinary blasting as they tend to be significantly more expensive than other materials that perform just as well in that field. Also, when an explosive is combined with a plasticizer, its power is generally lower than when it is pure.


Thank for Info : http://en.wikipedia.org

Putty



          Putty is a generic term for a plastic material similar in texture to clay or dough typically used in domestic construction and repair as a sealant or filler.Painter's Putty is typically a linseed oil based product used for filling holes, minor cracks and defacements in wood only. Putties can also be madeintumescent, in which case they are used for firestopping as well as for padding of electrical outlet boxes in fire-resistance rated drywall assemblies. In the latter case, hydrates in the putty produce an endothermic reaction to mitigate heat transfer to the unexposed side.


Thank for Info : http://en.wikipedia.org

Putty



          Putty is a generic term for a plastic material similar in texture to clay or dough typically used in domestic construction and repair as a sealant or filler.Painter's Putty is typically a linseed oil based product used for filling holes, minor cracks and defacements in wood only. Putties can also be madeintumescent, in which case they are used for firestopping as well as for padding of electrical outlet boxes in fire-resistance rated drywall assemblies. In the latter case, hydrates in the putty produce an endothermic reaction to mitigate heat transfer to the unexposed side.


Thank for Info : http://en.wikipedia.org

Epoxy putty

          Epoxy putty is a room-temperature-hardening substance used as a space-filling adhesive. It is stored until use as two components of clay-like consistency. Kneading the two components into each other creates an exothermic chemical reaction that activates the substance for use by catalyzing an epoxide polymerisation reaction. Unlike many other types of glues, an epoxy adhesive can fill gaps and even be molded into a structural part. Some makers claim in advertising that one can tap and drill their cured product, and that it quickly cures "hard as steel" (as measured by Shore rating), though it is much weaker than steel in tensile strength and shear strength.


Thank for Info : http://en.wikipedia.org

วันพุธที่ 4 กรกฎาคม พ.ศ. 2555

Adhesive


Adhesive

          Adhesion is the tendency of dissimilar particles or surfaces to cling to one another (cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are certain emergent mechanical effects that will also be discussed at the end of the article


Thank for Info :http://en.wikipedia.org

Hot-melt adhesive


Hot melt adhesive    

    Hot melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly supplied in solid cylindrical sticks of various diameters, designed to be melted in an electric hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which may be pushed through the gun by a mechanical trigger mechanism, or directly by the user. The glue squeezed out of the heated nozzle is initially hot enough to burn and blister skin. The glue is tacky when hot, and solidifies in a few seconds to one minute. Hot melt adhesives can also be applied by dipping or spraying. This was invented by Miles Kent in 1894.


          In industrial use, hot melt adhesives provide several advantages over solvent-based adhesives. Volatile organic compounds are reduced or eliminated, and the drying or curing step is eliminated. Hot melt adhesives have long shelf life and usually can be disposed of without special precautions. Some of the disadvantages involve thermal load of the substrate, limiting use to substrates not sensitive to higher temperatures, and loss of bond strength at higher temperatures, up to complete melting of the adhesive. This can be reduced by using a reactive adhesive that after solidifying undergoes further curing e.g. by moisture (e.g. reactive urethanes and silicones), or is cured by ultraviolet radiation. Some HMAs may not be resistant to chemical attacks and weathering. HMAs do not lose thickness during solidifying; solvent-based adhesives may lose up to 50-70% of layer thickness during drying.

Thank for Info : http://en.wikipedia.org

วันพุธที่ 14 มีนาคม พ.ศ. 2555

High Temperature Insulation Wool

In the 1950s, the term “Refractory Ceramic Fibre” was coined for the aluminium silicate fibres developed at this time. On account of their chemical purity and resistance to high temperatures (classification temperature >1000 °C) as well as on the basis of their use in other applications, this definition was made to differentiate aluminium silicate wools from the conventional “mineral wools”. Because of the ambiguity of the term “ceramic” and the development of new materials for the high temperature range, the nomenclature was changed to High Temperature Insulation Wool (HTIW) at the end of the 1990s.

Basically, there are two types of inorganic HTIW. In addition to the more commonly used amorphous HTIW (Alumino Silicate Wool ASW/RCF and Alkaline Earth Silicate Wool (AES)), Polycrystalline Wool (PCW) is also available. Owing to the costly production and limited availability compared to mineral wool, HTIW products are almost only used in industrial applications and processes up to 1800 °C.

REFRACTORY CASTABLES

Refractory castables can be used to create the monolithic linings within all types of furnaces and kilns. They can be further classified into the following sub-categories: conventional, low iron, low cement, and insulating for installation either by gunning or manually. There is a wide variety of raw materials that refractory castables are derived from, including chamotte, andalusite, bauxite, mullite, corundum, tabular alumina, silicon carbide, and both perlite and vermiculite can be used for insulation purposes.

Refractory-castable-Vitcas

CONVENTIONAL DENSE CASTABLES

Conventional dense castables are created with high alumina cement, and can withstand temperatures from 1300oC to 1800oC. These refractory castables are great for common furnace applications, burner blocks, speciality muffle furnaces and oiler work. Resistance is a key quality that varies with the choice of materials, resulting in abrasion, thermal shock and slag attack. Casting and gunning techniques are the method of installing the materials. For the ease of castable placement, gunning materials and water are combined together at the gunning equipment’s nozzle. This is a great method of placement for bulk materials, in cases when circumstances make formwork overly time consuming or simply impractical. In general, the method of installation will depend on cost and accessibility.

INSULATING CASTABLES

Another product that we supply is the Refractory castables that are low density. These insulating castables pose very low thermal conductivity and are utilized for either high temperature face work or when used for a backup lining, which is found behind dense castables or brick work. Here, the insulating castables are able to decrease the lining’s overall density or the cold face temperature. Their strength, which ranges from low to medium, is based on the fact that their density is low and is the main reason that they are not resistant to abrasion. They are most suitable where they do not have to stand up to much wear and tear.

LOW CEMENT CASTABLES

This type of refractory castable is prepared with a lower amount of cement than the standard dense castable is normally created with. Low cement castable refractories fluctuate in alumina content, which provides exceptional physical properties, including low porosity, great abrasion properties and high vigour. These products will commonly necessitate installation that is controlled, however, the big advantage of low cement castables is that they are easily pumped into position, and some may not require vibration, because they are free flowing.

Thank Infomation From : http://www.vitcas.com/

Refractory Castable

คอนกรีตทนไฟ (อังกฤษ: Refractory Castable) เป็นวัสดุทนไฟประเภทหนึ่ง ที่มีลักษณะและวิธีการใช้งานคล้ายกับคอนกรีตที่ใช้ในงานก่อสร้าง แต่เนื้อวัสดุที่นำมาใช้ผลิตเป็นคอนกรีตทนไฟ จะเป็น Refractory Material ซึ่งรวมถึง เม็ดวัตถุดิบหยาบ (Aggregate) และ สารประสาน (Binder) ซึ่งมักจะเป็น High Alumina Cement
[แก้]ประเภทของคอนกรีตทนไฟ

คอนกรีตทนไฟ สามารถแบ่งเป็นประเภทได้โดยเกณฑ์ที่แตกต่างกัน เช่น
1.แบ่งตามปริมาณ แคลเซียมออกไซด์ (CaO) ที่เป็นองค์ประกอบในเนื้อผลิตภัณฑ์ ได้ดังนี้
1.Conventional Castable เป็นคอนกรีตทนไฟ ที่มีปริมาณองค์ประกอบ CaO อยู่ในปริมาณสูง กว่า 2%
2. Low Cement Castable เป็นคอนกรีตทนไฟ ที่มีปริมาณองค์ประกอบ CaO อยู่ในกระมาณต่ำกว่า 2%
3. Cementless Castable เป็นคอนกรีตทนไฟ ที่มีปริมาณองค์ประกอบ CaO ต่ำกว่า 0.2%
แบ่งตามลักษณะในการติดตั้ง
1. Vibrating Castable คอนกรีตทนไฟ ที่ติดตั้ง โดยการหล่อแบบ โดยใช้การเขย่าช่วย
2. Self flow Casatble คอนกรีตทนไฟ ที่ติดตั้ง โดยการหล่อแบบ โดยใช้การ
3. Gunning Material คอนกรีตทนไฟ ที่ติดตั้ง โดยการใช้เครื่องยิง
1. Wet Gunning Material คอนกรีตทนไฟ ที่ติดตั้งโดยใช้เครื่องยิง โดยต้องทำการผสมกับน้ำให้เข้ากันก่อนนำไปติดตั้งโดยใช้เครื่องยิง
2. Dry Gunning Material คอนกรีตทนไฟ ที่ติดตั้งโดยใช้เครื่องยิง โดยไม่ต้องผสมกับน้ำก่อนนำไปใช้งาน
ผลิตภัณฑ์จะมีลักษณะเป็นผงแห้ง จะถูกบรรจุเข้าในเครื่องยิง แล้วจะถูกอัดด้วยแรงดันลม ไปตามท่อยาง จนถึงหัวยิง (Nozzle)โดยจะมีจุดเชื่อมต่อกับท่อน้ำที่ปลายท่อยิง ผลิตภัณฑ์จะผสมกับน้ำที่ ปลายท่อยิง ก่อนจะถูกยิงออกไป

Reractory Castable

Product Category : Material Handling Components
Reractory Castable Top & Bottom Blocks is used to hold the induction coil tightly in middle of the tilting furnace box with help of vertical tie rods. Thermafield Power Components Private Limited manufactures Reractory Castable Top & Bottom Blocks. Thermafield Power Components Private Limited supplies different types of induction furnace insulating materials, coil supports and non asbestose sheets, induction furnace hydraulic spares, carbon free hoses, hydraulic cylinders, he plates, duraline induction melting furnace assembly etc. Reractory Castable Top & Bottom Blocks is made from mixture of refractory material, S.S. Reinforcement and certain percentage of water to make the cast formation in fabricated mould. This Reractory Castable Top & Bottom Blocks give the base support to hold the coil and keep in shape while tilting of the furnace.

Salient features of Reractory Castable Top & Bottom Blocks are:
-Durable
-Fire resistant
-Heat resistant
-Chemical resistant
-High strength
-Flame retardant

Silicon Nitride Product

casatables are extensively used for back-up and hot face linings.
Their low density and low thermal conductivity helps in conserving heat energy and reducing fuel costs.

These are low iron content insulating castables, suitable for use in reducing atmosphere
with higher strengths coupled with the advantage of low thermal conductivities.