How much is the coefficient of thermal conductivity of brick of bubble tall aluminium?

Brick of bubble tall aluminium is the brick of light qualitative tall aluminous heat preservation that uses bubble law production, coefficient of thermal conductivity and system matter closely, porosity is more, heat conduction is lower.


Brick of bubble tall aluminium, say again for tall aluminous qualitative adiabatic firebrick, the combinative clay of grinding, aluminous grog and screening curium well wood chip, had matched in proportion, become slop with water agitate, mix in mixer in proportion with the bubble with good preparation again, make bubble slop. The bulk density size that bubble and slop scale inspect goods and calm. Bulk density is the bubble slop of Cm3 of ／ of 0.51 ～ 1.26g, can make bulk density be 0.4 ～ the goods of 1.0g/cm3.
Right amount foaming agent is added in pug, mix bubble and slop equably, classics is pouring shape, conserve, dry, firing and get firebrick of light qualitative heat preservation. Compare with other method photograph, the bleb stability that arises through bubble law is not quite good, should join firm bubble agent to last in order to assure foamy stability.
Foaming agent principle: Foaming agent is added in pure liquid, with agitate, mix, the mechanical method such as inbreathe, eject carries gas foaming agent can make in the liquid bubble. The foamy stand or fall that makes basically depends on foamy stability. What foamy stability points to is to generate foamy endurance fixity, namely bubble " life " accident. Basically depend on the stand or fall of quality of foaming agent oneself and outside element are affected to its.
Action of firm bubble agent: In foaming agent in epispastic process, firm bubble agent has an effect that nots allow to ignore. Foaming agent often with firm bubble agent answer deserves to use, firm bubble agent is glue commonly kind material, its element can produce bigger interior to grind when aqueous solution midstream is moved, taller; raised the viscosity that brings about solution then viscosity of foamy lilquid film, increased strength of lilquid film surface already, make the liquid of lilquid film drawing near not easy again eduction, the rate of decrescent of lilquid film ply is slower, waited time of lilquid film burst, increased foamy stability. Additional, the bubbly height of the solution after adding firm bubble agent can be less than the solution when adding firm bubble agent bubbly height. Its reason is increasing at solution viscosity, the skill that the place that increases unit appearance to accumulate requires to do also can increase, the watch acreage that when i.e. does coequal work, increases can be reduced, reduce bubbly height then.
Use wooden model or metal pattern, pouring shape. Bricky model is put in what have mat paper dry board on, bricky model working face wants besmear lubricating oil. To prevent goods generates air bubble and the influence organizes a structure, should slop of the slow bubble that note a person, turn over slop to mix or shake exhaust inside the model, scrape with board more than oar. Pouring good adobe belt model controls temperature to fall in 40 ℃ dry 18 ～ 20h, periphery of the model that wait for a brick pulls open the drawing of patterns when aperture of 3 ～ 5mm, add of succeed of drawing of patterns is dry, if use channel desiccator, its entrance temperature should not exceed 40 ℃ , outlet temperature does not exceed 150 ℃ . Adobe remains moisture is not more than 3 ％ , it is OK that big brick is not more than 1 ％ loading of kiln. Dry process is very important, if dry and undeserved conference appears crackle, sunken heart, drop edges and corners, the reject such as sticking to mould.
Use blaze pit commonly firing, yi Ke uses channel pit firing. Build a loading of kiln with silica brick commonly, adobe the code is being worn inside, code wearing does not exceed 1.6m commonly highly. According to bulk density size and Al2O3 content discretion, place of affirmatory loading of kiln and stop igneous temperature. Average volume density is low, the adobe outfit with Al2O3 low content is in upside, and the outfit with low both is in bottom, general and firing temperature is in 1380 ℃ of 1320 ～ , heat preservation 5 ～ 8h. Al2O3 content jumps over high products, stop igneous temperature is higher, be as high as 1580 ～ even 1620 ℃ . As a result of pouring shape the figure after goods is burned is average irregular, need abrade or cut plastics, make the appearance accords with use requirement, its manage changes index to reach each target that national level sets. Of tall aluminous adiabatic brick fireproof degree tall, heatproof shake sex is good, commonly used the high temperature thermal insulation of the kiln that make oven, good tall aluminous adiabatic brick, can use at the furnace kiln liner that contacts directly with blaze, but unfavorable the circumstance that with Yu Shourong broken bits erodes directly. It is good that because pledge tall aluminous brick is in gently,reducing atmosphere issues chemical stability, accordingly with hydric, the furnace pit that the gas such as CO makes protective atmosphere uses tall aluminous qualitative adiabatic liner commonly. Use temperature of light qualitative tall aluminous brick is 1350 ～ 1500 ℃ .
The reason bubble law with old thermal conductance of lighter than combustible law qualitative brick mixes brick of bubble law heat preservation the light qualitative firebrick that adds combustible legal system to build, although their composition is amiable aperture rate is same, but the thermal conductance that bubble law pledges the thermal conductance of firebrick wants lighter than combustible law qualitative firebrick gently is gotten greatly much, its reason depends on the microstructure of material differring. Can see when the observation below microscope, bubble pledges the constituent structure characteristic of firebrick is gas phase gently (stomatic) be surrounded by successive solid photograph, form beehive shape to close air hole structure.
The place before be like is narrated, close in this kind of air hole structure conduct heat in the process, the thermal conductance of solid photograph has main effect. And the microstructure characteristic of the light qualitative firebrick that produces with combustible law is different, it is inattentive poriferous structure, it is the microstructure of successive photograph at gas phase approximately, solid look is intermittent, by gas phase space, air can have very good thermal resistance effect, its thermal conductance is consequently lesser.
In recent years, the characteristic of the fireproof fiber that develops quickly and its goods is thermal conductance very small, the 1 ／ of the common light qualitative firebrick that is the same as for composition photograph only 4 ～ 1 ／ 3, this is attributed to the special organization structure of fireproof fiber material. In fireproof fiber and its goods, gas phase is successive photograph, distributing in the structure of successive network framework that makes by fiber, but the contact between fiber and fiber is the point contact that can become loose, cannot form the successive access of thermal current. Accordingly, structure of this kind of organization can rise to cut off very well to thermal current action.
How much is the coefficient of thermal conductivity of brick of bubble tall aluminium? 0.6 system are secret is 0.25, 0.8 system are secret is 0.29, 1 system are secret is 0.35, the coefficient of thermal conductivity with 1.2 secret system is 0.45W/m.k(350 ± 25 ℃ ) .