The properties of refractory materials

 Refractory inorganic nonmetallic material category, is the indispensable basic material, high temperature industry is mainly used in steel building materials non-ferrous machinery petrochemical industry the development of these industries are inseparable from the progress of refractory, refractory industry has become the fundamental guarantee of the national economy development, the escort for the steady development of high temperature industry in recent 20 years,?refractory material?industry of China is rapid development, has become the world's largest refractories production and consumption power, but also become the world's largest exporter refractory The increasing demand for?refractory materials?directly stimulates the rapid development of upstream?refractory?raw materials, and the reprocessing of raw materials is also an important development direction in the future.

Refractory mainly composed of magnesite bauxite, graphite alumina silica and other inorganic nonmetallic materials, plus a certain amount of additives, through a certain proportion of the allocation of inorganic nonmetallic?materials in the refractory?field is very widely used, huge refractory demand for inorganic nonmetallic materials has brought a broad market space.

Article Source:The properties of refractory materials
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
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Development of VOD ladle lining refractories

 Magnesia-chrome brick was first used in VOD ladle lining because of its excellent slag resistance. However, under intermittent operation of VOD ladle, magnesia-Chrome brick is easy to produce spalling damage and poor thermal shock resistance. Because of the environmental protection of hexavalent chromium, the use of chromium-containing refractories is more and more restricted. At present, domestic stainless steel steel mills have rarely used magnesia-chrome brick.

In Europe, VOD ladle lining is mostly made of (magnesium) dolomite bricks. Compared with magnesia-Chrome brick, dolomite brick has good thermal shock resistance due to its high temperature flexibility. Most VOD ladles in China use magnesium-calcium bricks fired at high temperature. Although magnesium-calcium brick has the function of purifying molten steel and has better thermal shock resistance than magnesium-chromium brick, the content of CaO in the brick reduces slag erosion resistance under the condition that the slag composition of VOD ladle varies greatly and is mainly acidic slag. Due to the hydration problem, magnesium-calcium brick is not suitable for intermittent production, and the management of storage, use and other aspects puts forward very high requirements.

In the smelting of low carbon and ultra-low carbon stainless steel, stainless steel plants are reluctant to use magnesium carbon brick for fear that the liquid steel may be carburized by using magnesium carbon bricks in VOD ladle. In fact, these problems can be minimized by using low-carbon magnesium-carbon bricks. Although low carbonization tends to reduce the thermal shock resistance, the bricks with excellent thermal shock resistance can be developed by selecting the best amount of special asphalt and antioxidant.

Article Source:Development of VOD ladle lining refractories
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: info@cxrefractories.com
Website:http://www.cxrefractories.com

Construction of Converter Refractories

The converter is an upright cylindrical smelting furnace that does not require an external heating source and mainly uses liquid pig iron as a refractory raw material for steel making. According to the nature of the furnace lining refractory, it is divided into two types: acid converter and alkaline converter. According to the part of the gas blown into the furnace, it is divided into a bottom blowing, a top blowing, a side blowing and a top-bottom composite blowing converter. Bottom blowing, top and bottom composite blowing converter bottom design breathable fire bricks. When laying, you need to locate the position of the ventilation bricks. The bottom blowing and side blowing blowing furnace bottoms are not designed with ventilated bricks, and the bottom of the furnace is relatively simple.
According to the bottom drawing of the converter, the production of magnesia carbon bricks for the bottom of the furnace is arranged, and each type of brick is used for production. The center brick of the bottom is processed bricks. According to the physical and chemical indicators of the design materials, the appropriate magnesia carbon bricks are selected for bonding processing. After processing, the cross reference line shall be drawn on the plane of the upper part of the center brick to provide a reference for positioning the ventilating bricks in the subsequent pre-laying and determining the position of the steel side and the steel side.
Breathable bricks need to be pre-made models. The model is generally made of wood. If the size is too small, it can be replaced by other refractory materials such as magnesia carbon brick. When processing ventilated bricks, special attention should be paid to technical indicators such as slightness, diagonal difference, and distortion. The dimensional deviation of the permeable brick directly affects the masonry of the steel mill. When making a ventilated brick mold, the dimensional tolerance should be controlled as a negative rule as much as possible. If it is a square rule, the steel factory may have a large gap around the ventilated brick.
In addition to the above refractory materials, it is also necessary to prepare sand at the bottom of the furnace (3mm-1mm), grinding tools, cutting machines, rubber hammers and other auxiliary materials.
Article Source:Construction of converter refractories
Company name:Henan Xinmi Changxing Refractory Materials Co.,Ltd
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Precautions when baking furnace

1. The furnace charge must be required, uniform medium and small refractory materials are needed, and the oven fabric must support the steel pan liner.

2. Carefully and carefully guarding the oven in the process of gradual feeding, and finding that the charge and steel pan are in time for fire treatment, the steel pan should be made to not melt before the molten steel is in place.

3. The first furnace of the oven should try to make the location of the molten steel close to the furnace mouth platform in order to facilitate the optimization of the sintered layer and to form the sintered layer of the upper furnace wall as much as possible so as to prevent the sand from falling when the upper mouth is not sintered to remove the residual steel pot. After the furnace is fused, the holding temperature must meet the requirements in order to increase the thickness of the sintered layer.

4. Barbaric operation is strictly prohibited.

5. Try to use less slag, more clean scrap, and use a slag treatment when the amount of slag is large.

6. Minimize soaking time when using high-Mn steel grades. Pay attention to the power supply curve of the cold furnace so as to close the cracks. Repair must be fine, as far as possible between the two refractory materials.

Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.

Article Source:Precautions when baking furnace
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
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On May 1, the VAT rate in the manufacturing industry will be lowered

From May 1st, 2018, the value-added tax rate for manufacturing and some other industries will fall from 17% to 16%.

The tax cuts have really benefited the refractory companies.

Upstream, downstream, and surrounding companies in the refractory industry will all be the beneficiaries of this tax cut. This VAT policy adjustment is generally expected by the market and companies. The tax cut exceeds the market expectation, which will bring huge benefits to refractory raw materials companies. This shows that China's value-added tax has been steadily advancing along the established modern value-added tax reform goals. Raise the annual sales standard of small-scale taxpayers, so that more small and medium sized refractory companies and start-ups can enjoy tax benefits.

Changxing refractory provides refractory products, calcium silicate products, castable & mortar, china refractory brick, ceramic fiber felt, ladle & tundish nozzle, ceramic fiber with high quality for you. Such as high alumina refractory bricks, magnesia carbon brick, clay refractory bricks and other refractory products.
Article Source:http://www.chinafirebrick.com/Company_News_163.html
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
Website:http://www.chinafirebrick.com/

Function of taphole clay

Stemming is used to seal the taphole refractory, at present there are water stemming and can be divided into two types: anhydrous stemming, the former is used in low pressure, strengthening smelting degree is not high, the small blast furnace, the latter in high top pressure, high degree of intensification of smelting of large and medium blast furnace.
Stemming form can be divided into two parts - refractory aggregate and binder. Refractory aggregate means corundum, mullite insulating firebrick, flint clay and other refractory raw material and modified materials such as coke, mica.Binder for water or organic material such as tar pitch and phenolic resin, also adding SiC Si3N4, expansive agent and additive, etc.Aggregate in a certain size and weight matrix, under the harmonic of binder has certain plasticity, thus can through the mud gun hitting iron mouth to block the molten iron.
With water as a bond is called the water stemming, tar, organic material such as resin as binder, called anhydrous stemming.

Main functions:
1) Wall, taphole requirements stemming good filling and sintering;
2) The stability of the iron to stemming easy open hole and resistance to erosion, erosion;
3) Protecting hearth, demand stemming rapid heating without crack, and the combination of old and new stemming high strength;
4) The opening performance is good, open machine drilling bit easily;
5) Moderate plasticity, facilitate mud gun operation and the formation of iron mouth balling;
6) Good volume stability, small volume change at high temperature, not contraction due to leakage of hot metal.

Anhydrous stemming advantages:
1) High strength, and maintain the stability of blast furnace condition (iron mouth depth, the tapping time fluctuations, whole taphole wind rate, etc.) is of great importance, which makes the blast furnace has a production base.
2) Slag resistance is strong.Stemming consumption is low, the general water cannon is one 5 of the mud.
3) It has a certain expansion performance. Have appropriate porosity and strength, can adapt to more than 2000 m.The large blast furnace use.
Article Source: Function of taphole clay
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: sales1@chinafirebrick.com
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Main factors affecting using life of blast furnace bottom and hearth

1.Design structure: Resonable design structure (salamander depth, material selection and arrangement) is the foundation of safety and long service life of blast furnace bottom and hearth.
2.Refractory raw material quality: Refractory material quality is the promise of safety and long service life of furnace bottom and hearth.The higher the price, the better the quality of the merchandise.In this respect, we have many lessons.
3.Construction quality:The quality of construction and material quality are equally important(Flatness of flat steel and screed、Gap and integrity of carbon brick、The density of ramming material and so on）.
4.Operation level：Improper operation will cause the hearth to be inactive , coke duichen sitting dead,the circulation of molten iron in hearth is aggravated. All these will affect the service life of furnace hearth.
5.Monitoring means: Only through modern monitoring methods, timely monitoring of the erosion of the hearth, the trend of development, to know the situation, and know why, so that we can nip in the bud.
There have many kinds of refractory products in our factory. What's more, there have many refractory news and refractory information in our website. Welcome to view our website and contact us anytime.
Article Source:Refractory castable material inspection before construction
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
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Website:http://www.chinafirebrick.com/