Mullite Lightweight Castables Construction Introduction
Mullite lightweight castables are a class of refractory materials used in furnaces that not only require outstanding high temperature performance, but also require a small bulk density and thermal conductivity. Lightweight mullite castables are refractory materials with excellent high temperature function and good thermal insulation. Because it uses high-quality composition materials, combined with low cement or micro-powder, it can be directly applied to high temperature parts with flame touch.
Mullite lightweight castables have high application temperature and can be directly touched and touched by flames for operation lining. The high temperature and energy saving is achieved; the unit weight is light, the structural component is reduced by 40~60%, the bricks of the top hanging bricks are eliminated, and the thermal conductivity is low. porous mullite aggregate ingredients, low thermal conductivity, good thermal insulation function; can quickly oven, shorten the furnace construction period, and obvious economic benefits.
Mullite Lightweight Castables Specification Introduction
Light mullite aggregates are the primary component of castables and have a crucial impact on the functional properties of castables. Care should be taken in selecting them. Properly improving the critical particle size of the aggregate is conducive to enhancing the compressive strength of the castable. However, if the critical particle size is too large, it will adversely affect the construction function of the data. After testing, we determined that the critical particle size is 12 mm. The ratio of granules to fine powder should be controlled at 65%~70%, and 32%~40% is suitable.
Mullite Lightweight Castables Applicaiton Introduction
Mullite lightweight refractory castable is suitable for petrochemical industry tubular heating furnace, light diesel oil, ethane cracking furnace lining, atmospheric and vacuum furnace, sulfur recovery equipment, steam boiler, tortoise shell insulation layer, two cylinders and pipe partition Hot single layer, other industrial furnace door, fire hole, investigation of hole door lining, etc.
Mullite Lightweight Castables Construction Preparation
The bottom layer must be cleaned and free of all kinds of sundries.
All kinds of anchors and hooks should be properly installed according to the planning requirements and be strong and reliable.
When forming a formwork, the manufacture and equipment of the formwork should meet the requirements of the quality standard.
When mullite lightweight refractory castables are directly touched by heat-insulated masonry or other refractory masonry, a barrier agent shall be provided on the masonry as required by the planning.
(5) Before construction, the insulation and casting refractory materials shall be matched according to the plan, and the cubic test blocks of a certain size shall be manufactured, and the normal temperature compressive strength test and the bulk density inspection shall be carried out.
Mullite Lightweight Castables Ingredients and Mixing
The application should be carried out according to the planned cooperation ratio. The measurement error of the bonding agent and the admixture is ±2%, and the measurement error of the lightweight aggregate is ±5%.
The refractory nproduct should be poured with the mixing. For Portland cement binders, the placement time shall not exceed 60 minutes; for bonding materials such as bauxite cement, water glass and phosphate, the placement time shall not exceed 30 minutes.
This product is mixed with a forced mixer, and the mixing time is not less than 5 minutes. Add 1/2 of water to the mixture, moisten the lightweight aggregate, and then join the cemented material, the powder and the remaining 1/2 of the water until the mixture is even.
(The heat-insulating mullite castable should be mixed until the color is uniform, the hand is kneaded into a dough, and it is easy to form.
Mullite Lightweight Castables Casting Process
The mullite lightweight castable should be layered and stratified, and the vibrating time should be shorter than the vibrating time of the refractory castable.
When the lightweight castable is required to be cast on the refractory castable, the refractory castable should be maintained for 24 h before pouring. When the cementing agent in the refractory casting is water glass or phosphate, the lightweight castable can be poured after the waterproof paper or plastic film is blocked.
When continuously pouring light castables at the joints, the loose parts of the outer surface should be cleaned and sprinkled with water and wetted.
The appearance should be smooth and compact, and there should be no cracks.
Maintenance guidelines should be based on the refractory cement used, either dry or no maintenance.
Mullite Lightweight Castables Baking Introduction
The quality of the baking directly affects the service life of the lining of the insulation mullite castable. Refractory castable should be strictly in accordance with the construction clarification and baking curve provided by the manufacturer. Which is forbidden to touch the open flame, castable is forbidden to heat up quickly in order to catch up.
