New Bharat Refractories Ltd. Alipore, Kolkata, West Bengal

Advantages ::     As blast furnaces and converters have become larger and more efficient, the use of torpedo cars has increased as it prevents heat loss from hot metal and the cost of construction as well as maintenance is comparatively low The torpedo car was originally used for transportation and storage of hot metal. But now hot metal pre-treatment (i.e. desiliconisation, desulphurization and dephosphorisation) has been separated from decarburization processing (done in a converter) and it is done in the torpedo car. Based on the need for corrosion resistance against FeO, Na2O and CaF2, Al2O3-SiC-C bricks have been developed comprising of alumina as the main aggregate, graphite which provides resistance to spalling and slag penetration and SiC which protects graphite from oxidizing.. Application ::   In different areas of Blast Furnace Ladle Car / Torpedo Ladle

The rotary calciner condition (11500C – 16500C), lining design (monolithic/refractory shapes) and refractory applications vary depending on the product type and kilns. To meet the critical operational conditions and to the at par with the best achieved performance and refectory consumption (1.25kg/t) overseas, specific qualities of Refractories are desired. The major problems faced with indigenous Refractories used in alumina calciners are high shall temperature and low abrasion resistance. Low cement/Ultra low cement constable (80 – 90% Al2O3) and refractory shapes of tailored properties are essential for overcoming these operational problems and achieving improved performance.

Advantages ::     The following factors are considered to be most influencing ones for the lining life of steel ladles: Slag basicity and fluidity of molten steelLong holding time of high temp. molten steelStirring action of molten steelThermal spalling from tem.Fluctuation Ladle handling method Ladle structural deignProcess constraintsTap conditionsLining/repairing method, etc. Lining of steel teeming ladle is divided into several zones including slag zone metal zone and bottom zone. The required characteristics of Refractories for each zone are as under ZONE in steel ladle Basic slag resistance Abrasion resistance Spalling resistance Hot strength Type of bricks used Slag Zone 0 X 0 0 Mgo-C Metal zone X X $ $ AMC / MgO-C Bottom zone X 0 $ 0 High alumina/Zircon/ MgO-C 0 - Most important$ - ImportantX - Moderate For metal zone, high alumina bricks were widely used. However, it has many problems such as structural spalling by slag penetration, damage to joints by slag & metal and shrinking after 25-30 campaigns. Alumina-magnesia spinal bricks show batter performance than high alumina brick in this area due to high corrosion resistance, slag resistance and tight brick joints. Recently, Alumina-magnesia graphite (AMG) bricks are used successfully. The opening at the brick joints is overcome by combining MgO in Al2O3-C bricks to provide a controlled/gradual continuous expansion of brick by spinal formation. With this combination, the joints will bot open during thermal cycling of the ladle, thus reducing pre-mature wear at the joints and avoiding steel & slag penetration to the cold end and consequently unexpected ladle break through MgO addition also improves corrosion resistance. However, excessive addition of MgO causes excessive expansion of the bricks, which may cause peeling.   Application ::   In Metal Zone of Ladles

Advantages ::   Zinc Zinc ore usually consists of sulphide minerals, which can not be directly reduced. Instead, the ores must first be calcined to convert the sulphide minerals into an oxide form, which then can be reduced by smelting. Smelting is roughly classified into two methods, the dry method and the wet method. In the dry method the oxide ore is miced with coke and heated to 1200 – 1300 degrees Celsius to generate zinc vopour. The vapour than passes into a condenser where it cools and condenses. In the wet method, the roasted ore is treated with sulphuric acid and the resulting solution is then electrolyzed. Lead The process of “roasting,sintering,blast furnace,electrolytic refining” which is known as “blast furnace method” is generally applied for lead smelting. Lead sulphide concentrates (Pb 65 – 70 wt %) are converted into oxide form by roasting. After roasting, the lead oxide together with coke and fluxes such as limestone are reduced in a blast furnace to form crude metallic lead (Pb 97 wt %). The profile of blast furnace for lead smelting is similar to the copper smelting process. The refractories include high alumina refractories (60-72 % Al2O3), fireclay high grog, mag-chrome & chrome-mag bricks, carbon bricks, acid resistant bricks, insulating refractories and monolithic (both alumino – silicate and basic).       Application :: The major locations of use are as follows   Sl. No. Refractories Location 1. High aluimina refractories (60-70% Al2O3) including bricks, ramming masses, castables Waelz kiln, clinker kiln Cupellation furnaces, retorts settlers, etc. 2. Fireclay high grog quality bricks Blast furnace 3. Fireclay other quality bricks and monolithics IF Kettles, refineries, Boilers, roaster, etc. 4. Mag-chrome and chrome-mag Waelz kiln and clinker kiln. 5. Insulation refractories Boilers, Waelz kiln Clinker feed chute, Kettle refining, DL maching, ignition hood, induction furnace, etc. 6. Carbon bricks and pastes Scrubbers 7. Acid resistant bricks Drying tower, acid mixing tower, absorption tower ( leaching, electrolysis & acid plant.)  

Kyanite is an important refractory mineral for the manufacture of high alumina refractories. Though similar in composition to silliminite, kynaite differs from the physical properties in that, on conversion to mullite by heating, kyanite undergoes volumetric expansion of 16% necessitating its calcinations prior to utilization.

Material : Kyanite

Application : Industrial

Form : Powder

Packaging Type : Bags, Gunny Bag

Packaging Size : 10 Kg, 30 Kg

Advantages ::   Glass Slumping / Kiln formed glass. When people are heating glass to a point where, at the right temperature gravity causes the glass to take a new shape. Forming glass in this way requires a mould to get the glass to form into or to allow the glass to slump to create a smooth concave or convex surface. Glass formed in this way can be used for plates, bowls, windows, furniture, panels and many decorative and artistic items. We are supplying a full range of products.   Our products include: Ceramic fibre blanket, board, papers, rope and braids Ceramic fittings Vermiculite products, board and loose Calcined alumina Insulating fire bricks Coating materials Element wire Kiln materials and repairs Glass Blowing. Glass is contained in either a crucible or tank furnace and is heated to a molten state for use to make formed objects. Glass made this way requires a furnace for holding and melting the glass, a glory hole for keeping the glass hot and workable and an annealing furnace for tempering the glass. Blown glass can be used for items from bowls and plates, sculptures, artwork to specialised equipment. We can supply material for your tank furnace, glory hole and annealing furnace.   Our products include: High temperature castables to 1800 C Fused cast (AZS Alumina Zircon Silica) items High alumina fire bricks and mortar Ceramic fibre products Insulating fire bricks Furnace materials and repairs  

WE ARE SUPPLIERS OF FLY ASH FROM VARIOUS THERMAL POWER PLANTS IN INDIA. FLY ASH CORRESPONDS TO THE FOLLOWING TEST RESULTS

Several courses of fireclay bricks are used in an electrolytic pot cell. Molten aluminum is an active reducing agent, which reacts with free silicon in refractory brick producing silicon as impurity in the metal. Similarly, free ferric oxide reacts with molten aluminum with a yield of iron.

In general, in the hot spot area where there is a higher thermal load, water cooled panels (made of cast Cu) are used and the other wall areas have water cooled panels of steel.   Advantages ::     If water cooled panels are not used magnesia-carbon bricks are installed in the hot spot area, with metal used unfired chrome magnetite brick in the other wall areas. The slag line area blow the water cooled panels is lined with Refractories that well withstand slag and molten steel and resist opening of brick joints and spalling. In former times, fusion cast magnesia chrome bricks and fired dolomite & magnesite bricks were used but at present, magnesia carbon bricks are widely used. Application ::   In Wall of electric Arc Furnace

Advantages ::   Tundish Refractories Tundish linings generally include a back-up safety lining and wear (service lining. The wear lining has commonly been burnt alumina bricks but in recent year there has been increasing use of low cement high alumina castable. Flow Control Flow control Refractories include two systems viz a sliding nozzle or sliding gate system and a stopper system. These systems are used to regulate the flow of molten steel from ladle to tundish and from tundish to mould respectively. Pouring refractories There are two types of pouring refractories viz. the long shround nozzle (ladle shroud) for pouring molten steel from ladle to tundish, and the submerged entry nozzle (immersion nozzle) from the tundish to mould. Both of these applications require corrosion and thermal shock resistance. In the early years of continuous casting, fused silica material was used but at present alumina graphite is the typical material for submerged nozzle. In the submerged entry nozzle there is an internal fitted nozzle with slits for argon gas bubbling as a way of preventing alumina inclusion in molten steel from causing build-up and nozzle clogging. On the exterior of the submerged entry nozzle at the slag line an insert of zirconia-graphite is included in the alumina-graphite body, to provide added corrosion resistance. Application ::   In various regions of furnace based on Continuous Casting

A coke oven battery is a complex structure of many different refractories shapes but it can be divided in general in to two sections; the regenerators which are the lower section and the coking and combustion chambers which represent the upper section. Advantages ::   The refractories used require good mechanical strength, thermal shock resistance abrasion resistance, volume stability and in the upper section good hot strength. Fireclay and silica are the principal refractories used with the latter in the upper section. Silica with very carefully controlled granulometry and tridymite and quartz content are essential to withstand the severe operational requirement of the coking and combustion chambers as coke ovens, with the appropriate repairs are expected to have a life of >30 years. Application ::   IN DIFFERENT AREAS OF COAK OVEN

Consequently, both chemical and thermo-mechanical conditions are very severe here. The primary criteria for Refractories to be used in these zones are that they should have higher tendency to form a stable coating of clinker which enhance the life of the refractory by protecting it against the mechanical abrasion and chemical action of the clinker. The usage of high alumina Refractories in this zone is diminishing with the advent of large diameter rotary kilns with pre-heaters and pre-calcinators due to increased thermal as well as mechanical load.

Burning zone and transition zone are the most critical zones of the cement rotary kiln where actual firing of the charge and clinker formation takes place. Consequently, both chemical and thermo-mechanical conditions are very severe here. The primary criteria for Refractories to be used in these zones are that they should have higher tendency to form a stable coating of clinker which enhance the life of the refractory by protecting it against the mechanical abrasion and chemical action of the clinker. The usage of high alumina Refractories in this zone is diminishing with the advent of large diameter rotary kilns with pre-heaters and pre-calcinators due to increased thermal as well as mechanical load. This eventually calls for the thermally efficient refractory lining in the rotary kiln. Keeping pace with the improved cement manufacturing technology has been increasingly specialized to offer the opimum possible solution to the cement manufacturers for increasing the life of Refractories lining. Further environmental considerations and disposal regulations in many countries have made the limitation in selection of Refractories for lining the rotary kilns. Super duty basic bricks of direct bonded mag-chrome and mag alumina quality are gradually substituting the presently used high alumina bricks. Magnesia Spinal Brick Magnesia Spinal bricks are found to the superior to mag-chrome bricks with regard to flexibility under pressure, resistance to thermal shocks, alkali and Redox stressing, they are used in marginal areas of sintering zone and transition zone with increased lifetime of about 20%. In the outlet side, the durability is improved by up to 40% in the marginal area. Due to absence of any iron oxide/chromium oxide, Redox problems are not experienced. Further there is a decrease in the influence of silicate infiltration and slag attack. Premature wear is caused by alkali salts and thermal overloading. Hence, need is felt to develop improved quality magnesia spinel bricks to achieve greater resistance to salt attack and higher thermal rating.

Solubility resistance to hot metal Penetration prevention of molten substances such as hot metal, etc. Superior thermal stress resistance High thermal conductivity Good spalling resistance. Keeping the above in view, new carbon blocks have been developed for improved characteristics such as: Prevention of matrix solution by adding alumina and by adding silicon Improvement of pore size distribution by improved forming method Improvement of deformability and thermal conductivity by using a lot of natural graphite.

All kinds of boilers require lining of refractory and unshaped products for production. We manufacture shaped and unshaped bricks used in various regions of the boiler.

As blast furnaces and converters have become larger and more efficient, the use of torpedo cars has increased as it prevents heat loss from hot metal and the cost of construction as well as maintenance is comparatively low

This furnace is a large structure, mostly built underground, on a floating foundation. It consists of several pits or cells. Several type of fireclay and insulation Refractories are used in these furnaces. High grog super duty bricks are mostly used in the flue duct. In back up walls and head walls, high duty and medium duty bricks depending on service conditions are being used. The furnace temperature varies from 13000C to 15000C.

Aluminum has gained a lot of importance in the field of metals in the recent past. India blessed with a huge reserve of bauxite, the basic raw materials for the production of aluminum, has rightly focused her attention on the development of aluminum industry in the country.

Advantages ::   Acid & Alkali proof bricks are specially made for regions which require acid and alkali proofing. The acid attack may take place where there is use of sulphur based materials which causes wear of ferrous lining of furnaces and tanks.   Application ::     Acid & alkali proof bricks have a varied usage in the following industries –   Zinc & Lead Industry for galvanizing   Power plants for chimney   Acid and Slurry tanks Oil Refineries and Distillarie