Electric stove hearth uses characteristic of function of magnesia brick firebrick

The function of magnesian calcic iron sand: Mineral photograph is MgO, C2F, C4AF, C2S, C3S

Characteristic: C2F content is high, agglomeration is admirable, it is good to fight FeO aggressivity, fight broken bits osmotic strong

   Electric stove basically has steel-making for main raw material in order to abandon steel. Wait for useless steel, lime add a person to arrive inside furnace, when electrify, electric arc happens between electrode and useless steel and heating furnace makings undertakes a series of metallurgy chemistry reacts, become useless steel refine steel. Electric stove basically has furnace of dc arc furnace, alternating current arc and inductive furnace to wait. Hearth depends on with the use of fireproof material the size of electric stove, hearth uses fireproof material to have magnesian carbon brick, magnesian qualitative dry type pounds dozen of makings to wait

 

   History of steel-making of furnace of alternating current arc is longer, because its hearth uses fireproof data,also passed changes. Begin to use bitumen tar magnesia or makings of bittern magnesia knot to pound hit into hearth. Erode because of bittern magnesia hearth faster, cannot satisfy use requirement, and although bitumen tar magnesia is durable the gender is better, but construction is troublesome, and have environmental pollution. Accordingly, the step of magnesian charcoal brick that uses magnesia brick and low class morely subsequently builds hearth. Hearth of bricky build by laying bricks or stones is durable the gender is very good, but build by laying bricks or stones is built take a lot of work take time, sometimes build by laying bricks or stones builds rise of bad meeting occurrence brick to cause manufacturing halt.

 

     To 20 centuries 90 time, our country begins to use hearth to do type to pound dozen of makings. Its construction is simple, convenient, need not roast, after construction is good, OK and direct steel-making casts a person to use. This material is department of magnesian calcic iron dry type vibration pounds dozen of makings. The iron acid that uses the low melting point that it contains is calcic, in warm up when 1200 ℃ above, can fast agglomeration generates strength. Can fast below the hydraulic pressure of molten steel agglomeration is contractive, its systole achieves 4% ～ 5% , bulk density increases 3.0 G/cm3 above. It is particularly good to have fight aggressivity and good use result.

   Fireproof material ton steel is used up by the 4 ～ 8 Kg of bitumen magnesia brick reduces 2 Kg before the following. Some modern electric arc hearth do ton of steel of type stuff to use up low amount to 0.3 Kg, this is main answer relatively with steel-making engineering technology; In use process, this material chases an agglomeration, standing by molten steel to be in agglomeration and compact change, those who fight molten steel erode and erode, agglomeration layer below is to transfer layer, falling again is inattentive not agglomeration layer. This inattentive layer density is low, thermal conductance is low, this has main effect to heat preservation of electric arc furnace. Through the promotion that comes for years and development, hearth of electric stove of our country great majority uses this kind to pound dozen of makings.

 

   The construction that hearth dry type expects and the crucial factor that using is effect use effect. This furnace footing should be called Gan Shizhen to move pouring makings for more appropriate. Because this material vibration is compact,the density that change hits than pounding want tall 0.2g/cm3 above, can make fight aggressivity to rise significantly. Triumphant luck gets kiln furnace to think this makings doing type should be oscillatory construction, the dc arc hearth that repairs to not easy heat more should such. When repair, must clear the broken bits of hearth and useless steel clean, when using fixed rate possibly otherwise, mat fuse in the slag that repairs makings below, fall in the concussion of bloom and make hearth expects rise. When tapping, the hearth of rise makings piece may jam tapping mouth and influence tapping. In use process, should observe hearth condition at any time, when occurrence rise, should repair in time (use commonly akin fill of 1000 type stuff is in to hole can) , prevented to rise expands further and prevent the happening of leakage steel phenomenon.

 

   The hearth of electric stove and bank slope formed bath jointly, its are fireproof data supports directly thermic load mixes high temperature to be eroded slaggily, molten steel erodes, useless steel machine is bumped and the oxidation below the high temperature inside furnace, reductive operation, make slaggy permeate to hearth, bring about hearth to decrease thin.

 

General component is the structure of bottom of freeboard power electric stove 3.

 

① thermal insulation namely hearth most lower level, its action is the hot loss that reduces electric stove, and the difference in temperature that assures to reduce bath to fluctuate, be in commonly rely on furnace casing place to spread an asbestine board first, spread diatomite pink again, brick of heat insolation of build by laying bricks or stones is made the same score on its.

 

② permanent layer is over thermal insulation, its action is the consistence that assures bath, have the effect end the mat that prop up. Use bricky step commonly, the fault seams build by laying bricks or stones 3 or so, use those who contain MgO95%~96% is firing magnesia brick, bitumen union magnesia brick, magnesian dolomite the brick, the brick is seamed fill up magnesia or the steel pink that pledge with material expect, squeeze close squeezing ramming.

 

③ job layer is above permanent layer, it is contacted with steel fluid directly, thermic load is high, chemistry erodes serious, machinery to erode action is extremely strong, easy corrode caustic, should choose high grade and fireproof material. Layer of the job end our country electric stove is united in wedlock by bitumen, use magnesia agglomeration or to calcine of electric frit, dolomite piece pound dozen of hearth or burn magnesia brick build by laying bricks or stones to build.

 

Current, the magnesian dolomite that power electric stove uses freeboard to the magnesium that contains a lot of2CaO·Fe2O pledges and contain a lot of2CaO·Fe2O commonly is qualitative (do not add any bond) compound. Pound dozen (it is lower berth actually) into integral structure hearth, its are durable the gender is tall.

 

Bottom of common power electric stove has two kinds of kinds normally.

 

① knot hearth (or vibration compresses hearth) . Working layer uses magnesia, its bond is tar, bitumen, and when making the lining that do not have carbon, make bond with bittern or water glass.

 

Hearth of ② brick build by laying bricks or stones. Combine the magnesia brick, lining that do not have carbon to combine magnesia brick with bittern with bitumen normally.

 

Place	Material is qualitative
Thermal insulation	An asbestine board, diatomite pink is spread on, brick of heat insolation of build by laying bricks or stones is made the same score on its
Permanent layer	Firing magnesia brick ( MgO95 ～ 96 ％ ) , bitumen union magnesia brick, the fault seams build by laying bricks or stones to build
Working layer	Knot hearth: Magnesia ＋ bitumen, tar (or bittern, water glass) , magnesian calcic iron sand Build by laying bricks or stones builds hearth: Bitumen combines magnesia brick, bittern to combine magnesia brick

Chemical composition, ％						Accumulation density G/cm 3
MgO	CaO	Fe 2 O 3	SiO 2	Al 2 O 3	Granuality Mm
≥82	6 ～ 7	7 ～ 8	≤1.5	≤1.0	0 ～ 8 0 ～ 5	≥2.40

Commonly used and fireproof material has electric stove: Diatomite brick, light qualitative adiabatic brick, magnesia brick.