Three categories of common refractory

Often used ordinary refractory:silica brick, half brick, fireclay brick, high alumina brick, magnesia brick and so on.

• Often used special materials are AZS bricks, corundum bricks, direct bonded magnesia chrome brick, brick carbide, silicon nitride bonded silicon carbide bricks, nitrides, silicides, sulfides, borides,
  
  carbides and other non-oxide refractories ; calcium oxide, chromium oxide, aluminum oxide, magnesium oxide, beryllium oxide refractories.

• Often used insulation refractory diatomite products, asbestos products, insulation panels.

• Frequently used unshaped refractories:fettling, refractory ramming mixes, refractory castable, refractory plastic, refractory clay, refractory gunning refractory cast materials, fire-resistant coatings, lightweight refractory castable, gun mud.

Green Refractories - Cement Industry Transformation

Strong cement kiln refractory way to go green development, to accelerate the transformation and upgrading of the cement industry to provide security services. Cement industry increasingly homogeneous competition incentives, in order to remain invincible in the fierce market competition, the need to strengthen security of supply, efforts in the management, strict cost control, propulsion meticulous management is the inevitable choice.

Refractories directly affect the operation of the furnace refractories, refractory cement enterprises are increasingly high requirements, pay more attention to quality and service, the traditional concept of price as the most important gradual changed.Currently a large group is more concerned about the high cost. Advocates around the industry and market demand, development of the industry also began refractory transition gradually transformed from a single manufacturing enterprise integrated service businesses, solutions-based business, product quality and service quality refractory more attention. By optimizing the quality and configuration of refractory extend its life, can greatly improve the operation rate of the cement production line, cement companies to reduce production costs, for the creation of value.

• Life is closely associated with the operation rate of the kiln refractories. 1995 "cement kiln refractory Use Regulations" (Trial) proposed kiln firing zone of six months, the transition zone 12 months. In actual use, the firing zone is generally 6-10 months (an average of about eight months), when firing with ≥ 10 months of the transition zone ≥ 12 months, the operation rate of the kiln will be greatly improved. This means that four years can reduce an overhaul, general overhaul to stop the kiln for 15 days, then increase the operating rate of 3.75 days / year.
• Optimize quality refractories, will help improve the production line of clinker production. By 2011 the national annual pre-kiln clinker 1.182 billion tons computing (average daily production of 3.24 million tons of clinker), clinker production line if the average yield increased by 1%, the annual production of more than 12 million tons of clinker, the annual savings 1390000 tons of standard coal and reduce CO2 emissions from 3.5 million tons. 
• Refractory quality optimization and life extension, effectively saving refractory cement plants use fees.
  
  According to incomplete statistics, China's cement kiln refractory consumption per tonne of clinker average of 0.4kg ~ 0.45kg, the advanced level of 0.3kg. Alkaline brick firing zone is used, for example, if the country's pre-calciner kiln firing line with the basic bricks used to extend the two month period, the annual savings from 9 to 10 billion yuan, about the rest of the types of refractories 3 to 400 million yuan, a total of about 12 billion yuan.
• Refractory quality optimization, help to improve clinker strength. In general, the intensity of clinker and clinker C3S content relevant, under the same conditions for the same raw material and fuel production kilns, clinker temperature when each increase of 4.5 ℃, the clinker C3S content increased by 1%, with the increase of intensity upgrade. And one key to improving the clinker temperature refractory brick kiln improve performance by increasing the clinker calcination temperature (can be increased by more than 10 ℃), thereby increasing the intensity of clinker and clinker C3S content.

Ten questions in using firebrick

1.Firebrick lining divided into four categories by brick gap size and sophistication of the operation.

Its category and brick gap size are:

   Class Ⅰ, ≤ 0.5mm;

   Class Ⅱ, ≤ 1mm;

   Class Ⅲ, ≤ 2mm;

 Class Ⅳ, ≤ 3mm.

Rotary kiln system with fire clay refractory lining masonry, mortar joints should be within its 2mm, the construction should be strictly controlled. Not move equipment lining the mortar joint, and the upper and lower inner and outer layers of brick joints should be staggered.

2.Modulating brick with refractory mortar should be prepared in accordance with the following principles:

•  Beforer Modulating brick shoud deal with various refractory mortar masonry pre-test and pre-determine the different bonding slurry time, initial setting time, consistency, and water;
•  modulating different mud shoud use different utensils and cleaned in time
• modulation of different quality mud to use clean water, water should be weighed accurately and reconcile should be uniform, with the tone with the use. Has prepared a good hard mud hydraulic and gas can not add water to use, has the initial setting mud shall continue to use;
• modulation phosphate binding provisions to ensure that the mud trapped material time, as used with the tune, has good modulation shall be arbitrarily diluted with water and mud. This mud is corrosive because not in direct contact with the metal casing.;

3,Firebrick varieties based on the design and layout of masonry. Masonry should be sought brick gap straight, smooth arc, masonry dense. For the refractory lining of the kiln cylinder must also ensure reliable concentric rings and brick kiln barrel, it should ensure that the brick kiln shell with full posts tight surface contact between the bricks should be firm and binding. When the device Not move masonry brick lining, fire mud plumpness requires more than 95%, use the puree pointing surface cracks between the blocks, but promptly scrape the surface of the excess mud brick lining.

4 Using a wooden hammer, rubber hammer or hard plastic hammer and other flexible tools to brickwork  and not use steel hammer.

5.Masonry should Not move Masonry fire insulation composite liners, should masonry hierarchical and segmentation, mixing is strictly prohibited mixed-layer Masonry, Masonry insulation lining also have to fill slurry full seam encountered when machining holes and welding parts to brick or board crevice use mud infill. Prohibition of arbitrary paved, mud everywhere, without leaving any gaps or practice. In the insulating layer, where the anchor is in the arch of the foot brick after brick, swelling around the holes and the contact areas

and shall use brick masonry.

6. Firebrick lining of the expansion joints must remain set according to the design, expansion joints shall be omitted from the width of the negative tolerance should not be left inside seam lumps of debris and use fire-resistantfiber will fill the joints, to avoid over the outer space phenomenon. Insulation layer is generally not to set expansion joints.

7. Form an important part of the complex parts of the lining should be pre-masonry. The structure is extremely complex lining of the processing may be considered to use castable lining.

8 Leaving in the brick lining of the exposed metal parts, including palm brick panels, brick retaining plates and other parts to use shaped bricks, castable refractory fiber or closed, may not be directly exposed to the hot gas kiln in use.

9.Anchor brick of masonry brick structure, according to the design requirements to stay located not missed. Hanging around the hole may not use cracked anchoring tiles. Pieces of metal hooks to hang flat real. Hanging hole and hooks can not stuck, the gaps remain available refractory fiber infill.

10. When capped brick Masonry, brick and curve fitting bricks, if original brick are not satisfied with the sealing requirements, use brick cutting machine cutting finishing not use manual processing tiles. Machining brick dimensions: the capping brick kiln and brick panels under the palm should not be less than 70% of the original brick; in joints and corners flat brick brick, brick shall not be less than the original 1/2 must use the original brick locking. Face of brick prohibited processing

Refractory introduction

Refractory refers to inorganic non-metallic materials that above 1580 ℃ refractoriness. Refractoriness means refractory cone sample in the absence of load cases, resistance to high temperature without melting down the softening temperature in Celsius.

Refractories and high temperature technology accompanied appears roughly originated in the mid-Bronze Age. China Eastern Han Dynasty have been made to burn wood and porcelain kiln sagger clay refractories. Early 20th century, the high-purity refractory, high density and ultra-high temperature product direction, while there has been complete without firing, small power consumption monolithic refractories and refractory fibers. Modern with the development of atomic energy technology, space technology, new energy technologies, high temperature, corrosion resistance, thermal shock resistance, erosion and other comprehensive excellent performance refractories has been applied.

Refractory variety, usually divided according to the level of ordinary refractoriness refractory (1580 ~ 1770 ℃), advanced refractories (1770 ~ 2000 ℃) and grade refractory (2000 ℃ above); divided by the chemical properties of acidic refractories, neutral and basic refractories refractories. In addition, there are special occasions for refractories.

Silicon oxide as the main component to acidic refractory, commonly used silica brick and clay. Silica brick containing 93% silica siliceous products, raw materials used are silica, silica brick scrap, with its strong acid slag corrosion resistance, high softening temperature under load, the volume does not shrink after repeated firing, even a slight expansion; but its vulnerability to erosion of basic slag, thermal shock resistance is poor. Mainly used silica brick oven, glass melting furnaces, steel furnaces and other acidic thermal equipment. To fire clay brick as the main material containing 30% to 46% alumina, is a weak acid refractory, thermal shock resistance, corrosion resistance to acid slag has wide application.

Oxide, chromium oxide or carbon are main component in neutralalumina refractory. Containing more than 95% of alumina corundum products is a wider use of high-quality refractory materials. Chromium oxide as the main component of chromium slag bricks for good corrosion resistance, thermal shock resistance, but poor low temperature load deformation temperature.

Carbon-carbon refractory bricks, graphite products and silicon carbide products, low coefficient of thermal expansion, high thermal conductivity, good heat resistance, vibration resistance, high temperature strength, resistance to acid and salt erosion, not metal and slag wetting, light. Widely used as a high-temperature furnace lining material, also used in petroleum, chemical autoclave liner.

Basic refractory magnesia, calcium oxide as the main component, is used magnesia brick. Magnesium containing more than 80% to 85% of the brick, alkaline slag and iron slag has good resistance, high refractoriness than clay and silica brick. Mainly used for open-hearth, basic oxygen furnace, electric furnace, high temperature and non-ferrous metal smelting equipment and some equipment.

Special occasions refractory oxide material has a high temperature, such as alumina, lanthanum oxide, beryllium oxide, calcium oxide, zirconium oxide, refractory material compounds, such as carbides, nitrides, borides, silicides and sulphides etc.; temperature composite materials, mainly metal ceramics, high temperature inorganic coatings and fiber-reinforced ceramics.

Strong demand for refractory transition

Orders declined, overcapacity is forcing the industry to accelerate the transformation of refractories, overweight and develop more environmentally friendly products, as well as infrastructure investment since last year makes the industry is ushering in a new turn.

Entering the new century since the

refractory industry has been developing rapidly. National refractory materials production from 10 million tons in 2000 to grow to 60 million tons a year now. 2012 production of 28.18 million tons of refractories, refractory accounting for over 65% of the world production, export volume of 2,039,700 tons.

However, fixed investment by weakening downstream industries, infrastructure to reduce the demand for refractories and other factors, in 2012 to reduce the number of refractories business orders, sales decline, coupled with funding constraints, companies have to shut down the furnace consumes the original inventory.

Recent research Refractory Industry Association of China Refractories 52 manufacturing enterprises showed that in 2012 representing a decrease of Refractories sales revenue of 4.29%, representing a decrease of 21.40% profit; since 2012, accounts receivable increased by 15.34 percent year on year.

To this end, the Ministry released yesterday "Several Opinions on Promoting the healthy and sustainable development of the refractories industry," comments pointed to 2015, the high-end refractory self-sufficiency, magnesite ore resources comprehensive utilization of not less than 90%,

refractory clay mineral resources comprehensive utilization rate of not less than 80%. By 2020, two kinds of mineral resources comprehensive utilization rate of more than 95% and 90%. And to promote the consolidation and reorganization, optimize the industrial layout, enhanced energy saving, eliminate backward production capacity.

It is in the policy guidelines "to promote joint restructuring" of some of the leading companies are constantly extend the industrial chain, to develop non-resistant products, and some companies to develop new building materials industry, and some seek in the field of mineralresources of iron ore, gold, etc. the new space for development, in order to enhance their own resilience. In addition, the policy of steady growth, driven by investment in infrastructure has increased since last year, refractories demand began to improve.

Analysts said that although overcapacity refractory low-end products, but in the context of energy saving, industry restructuring strong demand. In particular the construction of the new urbanization process, environmentally friendly Refractories in great demand, leading the company's future growth is no doubt

Chinese refractories industry entered the mature stage

China Refractories Association recently Xinmi in Henan Province held a national research forum refractory industry access conditions. Refractories from China Association,

China Association of mold material,Henan Province Department of Industry and representatives of 50 large enterprises to jointly explore the development of refractory ores on mining,industry access standards refractory materials, refractory products area.

Experts agree on the refractory industry standard enterprise seven basic views on 22 kinds of refractory materials,comprehensive energy consumption per unit of product limits, and 34 kinds of refractory raw materials, quality and technical standards of products 29 kinds of refractory products were defined.

The future of the industry will depend on the end of the past that production growth mode, the power comes from the continued growth of industrial upgrading. Access standards will limit the excessive growth of production capacity of refractories, refractory materials for new projects set a certain threshold, the long run contribute to the revival of the industry.

Insiders said the building materials, refractories industry into raising the threshold, the rapid integration of downstream customers,

rising technical standards would force manufacturers to improve their own technical standards refractories, no technical advantage of small manufacturers will face elimination, and technical advantages, capital advantage will enable leading companies get the opportunity to expand market share.

Agency analysts pointed out that at present, the refractory industry cycle matured, industry standards will bring opportunities related to corporate mergers and acquisitions

Andalusite Refractory plastic

Andalusite Refractory plastics production in China has not yet developed, nor the corresponding national standards, such as it is here referring to the current standard GB4758 its products for technical performance evaluation. To ensure the development of quality products, important physical and chemical testing and inspection work commissioned outside the domestic refractories testing authority - the Ministry of Metallurgical Industry Engineering Quality Supervision and Testing Center Station is completed.

• Main indicators of the chemical composition of the chemical composition of products for A12O3 (48 10%.)to 510: (42.60%), is a standard A12O3-510: series, the rest of the iron, and other impurities in Chin are not exceeded.
• Physical performance cold compressive strength: 180 ℃ x24h to 13,2 MPa, 1400 ℃ x3h to 31.7MPa; room temperature flexural strength: 180'Cx24h as 9.oMPa, 1400Cx3h to Z.6MPa; refractoriness: 17501770 ℃; bulk density: 2,059 / em,Luoyang plexiglass products high temperature flexural strength, flexural strength after burning room temperature flexural strength were better than the national standard, the performance is excellent, widely used in high temperature, high pressure resistance, thermal shock, high temperature corrosion resistance of various types of furnaces.
• Main characteristics (l) the main raw material for the andalusite , is A1203-510 series neutral refractories , which use temperature range : 1000-1700C. At room temperature viscoplastic strong adhesion large , especially for wall pipe location and structure complex and difficult construction sites and various other parts of the door opening .(2)can be naturally dry, construction site without any special maintenance; high consolidation strength after drying , shock resistance, resistance to cracking and swap blocks.(3)improve the use of parts of the structure and improve the furnace sealing performance , energy-saving effect is remarkable.(4)show strong thermal stability ,
  
  much better than traditional refractory concrete and other fire-resistant plastic .(5)high cost performance. Although the price is higher than the conventional refractory, but the technical indicators and all kinds of life is far greater than traditional materials , and the price of similar imported less than 1/ 2 of the product .(6)stable quality products for storage , transportation. In the cold north , the product is placed . 'C following storage , although the cold hard, but eliminate cold performance unchanged.(7)non-toxic, tasteless , non-corrosive , no pollution, no burning, no damage to the health of construction workers , are very safe to use and safekeeping .(8)at the construction site without the ingredients , mixing , formwork and water operations , the products can be used to open the package , you can improve working conditions, improve efficiency, shorten the construction period . The remaining material , as long as you can continue to use sealed , no waste .

Research of Laser cutting refractories performance

Bi-directional laser for differential absorption light detection and ranging, and will launch an emblem of the amount of gas resonance wavelength, then almost instantaneously transmit

a non-resonant wavelength, thus replacing the traditional dual laser devices. Two laser application in the free space optical channels: first, when the data stream is dense, continuous switching between the dual laser wavelength to supplement the data sets, one wavelength to another wavelength is the wavelength of the auxiliary; secondly, when the data and the flow rare, the laser wavelength becomes an equivalent division multiplexing transmission means for generating two independent data streams of different wavelengths.

It is estimated that the nation's ceramic device market is about 10 billion dollars, but due to the high cost of production of precision parts, further growth in the market is limited. Simultaneously or diamond abrasive grinding ceramic components is still the most common method of producing high mechanical strength and friability are often makes subsurface damage and breakage of the processing member. When using diamond tools, the technology will account for more than 75% of the total cost of processing a ceramic component.

One reason is that there are about $ 1 million for a diamond grinder. Although a laser machining has been studied as an alternative choice, but you may experience requirements for surface roughness between questions. Although the laser beam is not affected, but after treatment, some components exhibit a flexural strength decreases.

Laser cutting the material to be heated to above 1000 ℃ becomes soft ductile ceramic, boron nitride cutting tool and the three-dimensional soft heating layer removed. Experiment, the two structures that silicon nitrideceramics stabilized zirconia and local processing. Typical mechanical properties of a first material having a large class of structural ceramics, the latter having a coefficient of thermal expansion similar to steel, making it suitable for diesel engine parts.

In the intensity of the laser beam and laser processing conditions, such as precise control of laser assisted machining equipment to produce flake chip, rather than as the grinding process

that produces a powdery chips. Scanning electron microscopy showed that the wafer is relatively consistent and longer exhibit elastic deformation. The morphology of these chips is very important because it shows that laser assisted machining and grinding of different materials removal mechanism. Although early studies have shown that laser-assisted machining is not very appropriate, because under high temperature is raised, will shorten the life of the processing tools.