Formulation of High-strength Refractory Castables

The Formulation of High-strength Refractory Castables is a topic that people in the industry care about but avoid. By consulting various materials, I have found some formulas of high-strength refractory materials and refractory castables that can be disclosed to the public, which are shared for your reference only.

High-strength Refractory Castables

Introduction to Refractory Materials

Refractory material is an indispensable basic material for manufacturing industrial furnace linings and high-temperature vessels and components. It is widely used in high-temperature fields such as metallurgy, glass and cement. According to the construction process, refractories can be divided into qualitative refractories and unshaped refractories. Among them, unshaped refractories have been widely used because of their advantages such as low production cost, low energy consumption, simple process, etc. In many countries, the output of unshaped refractories has accounted for more than 50% of the total refractory materials.

High Alumina Refractory Castable

It is well known that amorphous refractories are a mixture of aggregate, matrix, binder, and additives. Among them, the binding agent is a material having a certain strength by bonding the refractory aggregate and the matrix together, and is an important component of the castable. At present, commonly used binders include phosphate, α-Al2O3, ultrafine silicon powder and aluminate cement. Aluminate cement has become an indispensable hydraulic binder in the refractory industry due to its high early strength, fast setting speed at low temperature, and strong resistance to high temperature, weak acid and alkali erosion. It is widely used in refractory materials. However, when aluminate cement is used as a binder, the curing process of the refractory castable is complicated, and the volume of the refractory castable is easily changed during the hydration-dehydration process. Easy to crack and peel.

For this reason, some researchers have successively developed low-cement (1.0% <CaO <2.5%), ultra-low-cement (0.2% <CaO <1.0%), and cementless (CaO <0.2%) combined refractory castables. Among them, cementless binders mainly include hydrated alumina, silica sol, alumina sol, and the like.

Low Cement Wear Resistant Castable

The refractory castable formula provided herein aims to overcome the shortcomings of the prior art, and aims to provide a method for preparing a high-strength refractory castable with a simple process and a short production cycle. The high-strength refractory castable prepared by this method not only has good fluidity, but also has early strength, medium-temperature strength, and high-temperature strength.

Formula of high-strength refractory castable

In order to achieve the above purpose, the following technical scheme is adopted in this formula: The raw materials and content of the high-strength refractory castable are:

Corundum or alumina with a particle size of less than 8mm and 5mm or more 5 ~ 15wt%;

Corundum or alumina with a particle size of less than 5mm and 3mm or more 5 ~ 15wt%;

Corundum or alumina with a particle size of less than 3mm and 1mm or more 5 ~ 15w%;

Corundum or alumina with a particle size of less than 1mm and greater than or equal to 74μm 10 ~ 30wt%;

Corundum or alumina with a particle size of less than 74μm 10 ~ 30wt%;

α-alumina fine powder 5 ~ 15wt%;

Aluminate cement 1 ~ 10wt%;

Water reducing agent 0.1 ~ 0.4wt%;

Water 3 ~ 7wt%;

Silica sol 0.1 ~ 10%.

Preparation method of high-strength refractory castable

According to the raw materials and content of the above-mentioned high-strength refractory castables,

First, the raw materials of the high-strength refractory castable are mixed,

Then, add water and silica sol and stir to obtain a mixture;

The mixture is then poured into a mold, vibrated, cured, demoulded, and heat treated to produce a high-strength refractory castable.

Components of raw materials for high-strength refractory castables

The corundum is one or more of plate corundum, white corundum, sub-white corundum, and brown corundum; and the Al2O3 content of the corundum is> 95wt%.

The alumina is one or more of super-grade alumina and first-grade alumina; the Al2O3 content of the alumina is> 70% by weight.

The particle size of the α-alumina fine powder is 1 to 10 μm, and the Al2O3 content of the α-alumina fine powder is> 98% by weight.

The main components of the aluminate cement are: Al2O3 content> 68wt%; CaO content> 29wt%.

The water reducing agent is one of a naphthalene-based water reducing agent, a sulfamate-based water reducing agent, a polyethylene glycol-based water reducing agent, and a phosphate inorganic water reducing agent.

The silica sol has a concentration of 10-50% by weight and a particle size of 5-100 nm.

The heat treatment process is as follows: the temperature is raised to 1100 to 1600 ° C at a rate of 1 to 20 ° C / min, and the heat is maintained for 2 to 4 hours.

RS Steel Fiber Refractory Castable Manufacturer

Advantages of high-strength refractory castables

Due to the adoption of the above technical scheme, the produced high-strength refractory castable has the following positive effects:

The formula is simple and the production cycle is short;

The prepared high-strength refractory castables not only have good flow properties;

Early strength, medium temperature strength and high temperature strength are high.

Notes: The formula of the above high-strength refractory castables is for reference. The preparation and construction of high-strength refractory materials for specific thermal equipment also need to be configured and guided by professional refractories experts according to the working conditions.

RS Castable Refractory Production Line

Rongsheng refractory castable manufacturer

Rongsheng refractory manufacturer is a professional manufacturer of refractory castable, high alumina castable, light castable, mullite castable, wear-resistant castable, non-stick aluminum castable, steel fiber castable and other castables . Rongsheng's refractory products have passed ISO international 9001 quality system certification, the products meet international standards, and have been exported to Southeast Asia, South America, Africa and other countries and regions. If your thermal equipment requires refractory castables, you are welcome to consult.  contact us. http://www.aluminabricks.com/contact-us/.