Classification and application of refractory ramming materials in glass kilns
Refractory ramming mass
is with reasonable gradation of granular and powdery refractory materials, add an appropriate amount of binder mix and practice, it is dry or semi-dry loose mud material, according to the national standard stipulated deformation index is less than 15%, need to be strong ramming to dense, it is called refractory ramming material.
Refractory ramming material with refractory materials
used named, such as zirconium ramming material (acid), jade-quality ramming material (neutral), magnesium ramming material (alkaline), according to the conditions of use. Due to the direct contact of refractory ramming material with molten liquid, refractory materials are required to be able to resist erosion, volume stability (to achieve zero expansion) and very dense (related to material grading). According to the material and use requirements of the choice of binder, commonly used in a variety of inorganic binder, such as aluminum phosphate, sodium phosphate, aluminum sulfate, sodium silicate, magnesium chloride, sometimes also add organic binder. In some ramming materials, refractory fibers are also used as reinforcement.
The strength of refractory ramming material at room temperature before sintering is low, and only after sintering can it have high strength. Therefore, various high temperature properties and service life of refractory ramming materials are related to the sintering quality before use. Sintered body should not shrink, no expansion, no crack, with the underlying firebrick combination.
Glass furnace bottom ramming material multi-purpose zircon sand, its composition (%) : ZrO2:62, SiO2: : 32, Al2O3, Fe2O3 2:0.5, volume density is greater than 3 g/cm3, refractoriness above 1790 ℃, the largest particle size 0.5 mm. Binders with aluminum phosphate dihydrogen, binding firm, high strength, high temperature resistance, but easy to dry caking, should not be put for a long time, the skin has a certain degree of corrosion, the use of inconvenience. Has been gradually converted to zirconium corundum ramming material (the French brand as ERSOL). AZS brick waste is often used as refractory aggregate. The composition (%) of the rammer is zro2:30, SiO2:48, al2o3:20, the mineral phase is alpha-al2o3, mullite, zircon, glass phase, the maximum particle size is 5mm. When using only need to add water mixing, the volume density of 3.2 g/cm3, porosity rate was 12%, the precipitation bubbles tend to be weak, glass erosion resistance under 1400 ℃. It can also be used as sealing layer and mud material.
Recently, low shrinkage AZSC ramming compound has been developed and applied in China. It is a basic ingredient in AZS introduced in a certain amount of chrome material, acuity 2.9 g/cm3 volume density, linear shrinkage (3 h under 1400 ℃) is less than 0.2%, glass and metal erosion resistance is better than the above two kinds of ramming material. Use as long as water mixing, can also be used as a sealing layer and pouring material.