Refractory plastics do not trap materials in advance. If the gas is too large, the product will expand and its strength will decrease.
Before you want to know about refractory plastic materials, you need to know the types of refractory plastics.
Refractory plastics are divided into different materials such as clay, high alumina, aluminum silicon carbide, silicon, magnesia, etc. The binders include water glass and phosphoric acid. In terms of actual use, phosphoric acid cement is used relatively frequently, but the refractory plastic combined with phosphate cement must be trapped, and the trapped time should not be less than 18-24 hours.
Reasons why refractory plastics are trapped
The reason why refractory plastics need to be trapped is that there are certain impurities in the raw materials of the plastics. These impurities will react with the phosphoric acid binder, and a large amount of gas will be formed after the reaction. The gas will expand the inner parts of the plastics, causing The structure of the material is loose and its strength will decrease after hardening. The purpose of trapping material is to allow the gas to be fully discharged after being placed for a period of time. After the gas is discharged or during construction, the remaining binding agent is added, so that the plastic function can be fully utilized.
If it is a water-glass bonded plastic, a binding agent can be added during on-site construction. At present, due to technological innovation, an extruder is used to extrude refractory plastics into small cubes before use, and are packaged and stored in plastic bags. They can be opened and used during use, so there is no problem of trapped materials. Because during the storage process, the material has been trapped. This method of production extrusion is generally only used for export products.
Refractory plastics used in China are not extruded. A part of the binding agent is added during the production process, and the material has been trapped during transportation. When used, it is opened and the remaining binding agent is added for mixing, and it can be used directly. But it should be noted that the time must be controlled after 18-24 hours. If it is a short-distance transportation, just control the time. Material trapped on site delays labor. If materials are trapped first, there is no need to trap materials on site, which saves time and meets construction needs.
