Low Creep High Alumina Refractory Bricks
Introductions
Low creep high alumina refractory is a kind large refractory material with large proportion in mass. Low Creep High Alumina Refractory Brick is made from it, for its low creep character, it is also called low creep high alumina brick. Normally it is used in high-temperature industrial furnaces under long-term high-temperature environments. Common low creep refractory bricks include low creep high alumina bricks and low creep clay bricks.
The development of high thermal shock and low creep high alumina bricks is based on the synthesis of M45 mullite fire brick as the main raw refractory material, and the matrix is added with M75 mullite fine powder. Reasonable selection of three stone raw refractory materials (kyanite, andalusite and silimanite), refractory soil as binder, scientific design components, research and development Under 1100 ° C water-cooling conditions, the thermal shock stability is greater than 55 times (only fine mesh patterns appear), 1350 ° C * 0.2 MPa, 20 ~ 50 h creep rare<0.2% about high thermal shock low creep high chrome brick.
Low Creep High Alumina Bricks Technical Index
Item | XHJLCB-70 | XHJLCB-75 | XHJLCB-80 | XHJLCB-65 | XHJLCB-55 | XHJLCB-48 |
Al2O3, % ≥ | 70 | 75 | 80 | 65 | 55 | 48 |
Refractoriness ℃ ≥ | 1790 | 1790 | 1790 | 1790 | 1770 | 1750 |
Apparent porosity % ≤ | 20 | 20 | 19 | 24 | 24 | 24 |
Cold crushing strength MPa ≥ | 65 | 70 | 80 | 49 | 44.1 | 39.2 |
Reheating linear change rage % ≥ | ±0.1 | ±0.1 | ±0.1 | +0.1~-0.4 | +0.1~-0.4 | +0.1~-0.4 |
1450℃*2h | 1500℃*x2h | 1450℃*2h | ||||
refractoriness under load (0.2Mpa) ℃ ≥ | 1500 | 1550 | 1650 | 1500 | 1470 | 1420 |
Creep rate % ≤ | 0.6 | 0.6 | 0.7 | – | – | – |
1350℃×50h | 1450℃×50h | 1500℃×50h | – | – | – | |
Low Creep High Alumina Bricks Characteristics
l Good thermal shock resistance.
l Good abrasion resistance.
l Good corrosion resistance.
l Good high temperature mechanical strength.
l Good volume stability, low creep rate.
With the development of modern smelting technology, hot blast stoves generally adopt high air temperature technology, and the service life of hot blast stoves is required to be longer: therefore, higher requirements are put forward for the comprehensive performance of refractory materials for hot blast stoves. Damage to refractory materials used in hot blast stoves is usually caused by thermal stress, chemical attack, and mechanical loading. It is generally believed that an important reason for the damage of the hot blast stove is that the high temperature creep resistance of the refractory material is poor, resulting in collapse, deformation and cracking of the lining refractory material, thus causing widespread concern for low creep bricks for hot blast stoves.
Low Creep High Alumina Bricks Applications
Although Low Creep high alumina bricks have very high refractoriness, their refractoriness under load is relatively low. Low creep high alumina bricks have higher mullite content and lower glass phase, so they have higher thermal shock resistance, lower creep rate and higher refractoriness under load. Low creep high aluminum bricks are widely used in high temperature industrial kilns and furnaces. For example, inner lining of hot blast furnaces, glass melting tank where doesn’t contact with glass liquid, regenerator checkerwork and so on.