As a supporting equipment, the dryer is a necessary production link for many industrial kiln. The high -temperature working environment. In order to achieve energy saving and improve drying efficiency, the refractory material has become an indispensable process in the dryer. In view of the fact that it is given to the dryer. In the special working space of the dryer, when we choose the refractory material for the dryer, we generally use the monolithic refractory material -castable, which is better in the construction and the effect of use.
The choice of casting material for dryer
The selection of dryer castables should be based on the nature of the finished products of the dryer to do the final physical and chemical indicators. Generally speaking, in the dryer castables, low cement refractory castables are widely used.
Low cement castable refers to castable with low cement content. The cement content of refractory cement castable is generally 15% ~ 20%, the cement content of low cement castable is about 5%, and some even reduce to 1% ~ 2%. The purpose of reducing the amount of cement is to improve the fire resistance of castable.
Advantages of low cement castables
(1) Because the cement content is only 1/15 -- 1/2 of that of ordinary refractory castable, the castable is reduced from 2.5% -- 8% to 2.5%, the number of low eutectic phases formed in the matrix is greatly reduced, and thus the refractories, high temperature strength and slag resistance are improved. At high temperature, the low melt content is reduced, and the wear resistance, high temperature bending strength and softening temperature under load are also significantly improved.
(2) Mixing water demand only ordinary refractory flexible injection 1/3 - 1/2(4%-6%), so low porosity, high volume density, and the same material fired into refractory products phase Shuomei. The strength of castable varies with the amount of water added.
(3) After forming and curing, the cement hydrate is less or no cement hydrate, and there is no problem that a large number of hydration bonds are destroyed and affect the strength during heating and baking, but with the increase of heat treatment temperature and gradually sintering, the strength also gradually increased. Especially different from the ordinary refractory castable, the mechanical strength is higher than the drying strength in the middle temperature zone (900-1200 notes). Both high temperature and normal temperature strength is better than ordinary refractory castable.
Dryer castables have the advantages of high density, low porosity, good thermal strength, high refractoriness and high softening temperature under load, strong erosion resistance, good wear resistance and good thermal shock resistance. Its performance can be matched with fired refractory products, applied throughout steel, machinery, chemical and building materials and other fields, and obtain good results.
