Refractory clay knowledge introduction
mortar is abbreviated as fire mortar. Refractory mortar is available in bag and barrel specifications. Its purpose is to build refractory bricks. The material is based on the bricks to be built. It is recommended that the material content of mud is higher than that of bricks, which will have a longer wear life.
Refractory cement ratio
①The raw materials of clay bricks and high-alumina bricks
are high-grade cement or high-alumina cement (refractory cement) and refractory soil above No. 425. When building high-alumina bricks, the content of Al2O3 is more than 40%; when building clay bricks, it is 20%-40%, the ratio of the two is 1:2 or 1:3, add water and stir (the ratio of water to refractory mud is about 0.7:1), and adjust it to a thick paste without lumps. If water glass is used instead of water, the effect is better. Before mixing, water glass is diluted with 1:1 water, and then mixed with cement and refractory soil to make refractory mortar
②The iron-magnesium mortar is used for the construction of magnesia refractory bricks, and the materials shall be prepared according to the mass of refractory bricks at 5% to 6%; when the magnesia bricks
are constructed, the materials shall be prepared at 8%-10%. The diameter of the magnesia fine material used is less than 1mm;
③ Phosphate refractory cement is used to build phosphate refractory bricks or phosphate abrasion resistant refractory bricks. The blending of cement shall use industrial phosphoric acid with a concentration of t>85% as blending agent.
④The mixing ratio of refractory mortar for insulating refractory bricks is diatomaceous earth or refractory earth
Precautions in the use of high temperature refractory cement
Refractory clay is a new type of inorganic cementing material made by adding inorganic binders with powders of the same material according to the requirements of the material and temperature of the masonry bricks. It is divided into four grades: 1300, 1400, 1500, and 1700. It is suitable for kiln masonry requiring small mortar joints, good sealing performance and high bonding strength.
1. When repairing the furnace, if the cracks are too large, 2-3mm refractory particles can be appropriately added to the high-temperature refractory mortar, and the joints can be filled with mixing to shorten the repair time and ensure normal production.
2. It can be applied in various furnace bodies, and the surface of the furnace body should be free of dust and debris before applying. Especially when constructing on old furnaces, the slag wax and other dirt should be removed.
3. It can be applied manually or mechanically, and the thickness is generally 2-3mm. It cannot be applied because it is too dry during use. It can be mixed with an appropriate amount of water.
4. High temperature refractory mortar should be strictly prevented from mixing with other materials, especially cement, lime and other items.