Izitena zealumini ephezulu

A. High alumina brick application

Mainly used for lining of blast furnaces, hot blast furnaces, electric furnace tops, blast furnaces, reverberatory furnaces, and rotary kilns. In addition, izitena eziphezulu zealumines are also widely used as open hearth regenerative checker bricks, plugs for pouring systems, nozzle bricks, etc. However, the price of high alumina bricks is higher than that of clay bricks, so it is not necessary to use high alumina bricks where clay bricks can meet the requirements. To

B. Performance of high alumina bricks:

(1) Refractoriness

Ukuphindaphindwa kwezitena eziphezulu zealumina kuphezulu kunezitena zodongwe kunye nezitena ezinesilica, ezifikelela ku-1750 ~ 1790 ℃, ezizezinto ezinqabileyo eziphambili. Ukuchaphazeleka kwakhona kuchaphazeleka ikakhulu ngumxholo, uhlobo kunye nobungakanani be-Al2O3, kunye nokuphinda kubonakalise ukunyuka njengoko umxholo weAl2O3 unyuka.

(2) Load softening temperature:

Ngenxa yokuba izitena eziphezulu zealumina zineAl2O3 ephezulu, ukungcola okuncinci, kunye nemizimba yeglasi encinci enefusus, umthwalo othomalalisa ubushushu uphezulu kunowezitena zodongwe. Nangona kunjalo, ngenxa yokuba amakristali e-mullite engenzi ubume benethiwekhi, ubushushu obuthomalisayo bomthwalo abukho njengobude bezitena zesilica.

(3) Thermal conductivity:

Izitena eziphakamileyo ze-alumina zinokuqhuba okungcono kwe-thermal kunezitena zodongwe. Isizathu kukuba kukho izigaba zeglasi ezimbalwa ezinobunkunkqele obusezantsi kwimveliso ephezulu yealuminium, ngelixa inani leekristale ze-mullite kunye ne-corundum ezinokuqhuba okungcono kwe-thermal, ezonyusa ukuqhuba kwe-thermal kwemveliso.

(4) Thermal shock resistance:

Ukuxhathisa kukothuka kwe-thermal kwizitena eziphezulu zealumni kuphakathi kweemveliso zodongwe kunye neemveliso zesiliceous. Umjikelo wokupholisa amanzi ngo-850 ° C kuphela ngamaxesha ama-3 ukuya kwezi-5. Oku ikakhulu kungenxa yokuba i-corundum inokwanda okuphezulu kwe-thermal kune-mullite ngaphandle koguquko lwekristale. Okwangoku, kunokwenzeka ukuphucula ulwakhiwo lwamasuntswana emveliso, ukunciphisa umxholo womgubo ocolekileyo, kunye nokunyusa ubungakanani beqhekeza elibalulekileyo kunye nokuhlulwa kwamasuntswana e-clinker ukuphucula ukuxhathisa kukothuka kwemveliso.

(5) Slag resistance:

Izitena eziphakamileyo ze-alumina zine-Al2O3 engaphezulu, esondeleyo kwizinto ezingathathi hlangothi, kwaye inokuxhathisa ukhukuliseko lwe-slag ene-acid kunye ne-alkaline slag. Ngenxa yokubandakanywa kwe-SiO2, ukubanakho ukumelana ne-alkaline slag kubuthathaka kunaleyo ye-acidic slag. Ukongeza, uxhathiso lwe-slag lwezitena eziphezulu ze-alumina zikwanxulumene nokuzinza kwemveliso kwi-slag. Ngokubanzi, emva kokubumba koxinzelelo oluphezulu kunye nokudubula okuphezulu kobushushu, iimveliso ezineporosity esezantsi zinokuxhathisa okuphezulu.

The parameter index of high alumina bricks varies widely, and its physical properties should be determined according to the grade of the product and the place of use when it is used. At present, the general high alumina brick standard GB2988-88 is generally adopted. If you need to use super high alumina bricks, please refer to GB/T 2988-2012 standard physical and chemical indicators. The index of high alumina brick is the basic performance requirement. According to the conditions of use, creep resistance and thermal shock resistance should also be considered. The chemical resistance directly depends on the A12O3 content and porosity.

(6) Physical and chemical indicators: