The particle size of refractory plastics has an impact on construction but has no impact on use. On the contrary, plastic castables with larger particles will have a longer service life.
However, it should be noted that in special parts, especially those that are difficult to construct, there are still certain requirements for particles. The main reason is that if the particles are large, it is not easy to pound and construct. When the particles are too large, the construction efficiency will be low. However, if the particles do not exceed 10mm, as long as the construction can be smooth, there will be no problems in use, and the service life will be longer than that of plastic castables below 3mm.
The plasticity index of refractory plastic is 15-40%. If the plasticity index is lower than 15%, the plastic will be too hard and cannot be constructed. However, if the plasticity exceeds 40%, the material will be too soft. If it is too hard or too soft, it will not be easy to construct, and it will not be dense when pounded. The most suitable state for the refractory plastic index is when it can be kneaded into a ball by hand, and it is not watery or sticky.
Refractory plastic castable has its own characteristics. Generally, its strength is low at room temperature, does not decrease in strength at medium temperatures, has high strength at high temperatures, and has good thermal shock and peeling resistance. However, the lining body that is pounded during construction must be welded with anchors or supports, so as to improve the performance of the refractory plastic and extend its service life.
During the construction of refractory plastic castables , the materials must be trapped before use. The trapped time should be more than 16 hours. However, if the production and official use time are short, the manufacturer can add 2-5% binder during production. The material trapping time has been completed during the transportation process, and the remaining binder is added directly during the formal construction, and the ramming construction can be carried out immediately.
If it is stored for a period of time after production before construction, then one-third of the binder should be added to trap the material for more than 16 hours before construction, so that after the binder is added, the calcium and potassium in the material can be fully discharged. gas, and then add the remaining binder before construction can begin.
In short, the particle size of refractory plastic castables does not affect its use, whether it is trapped on site during construction or added with binders at the manufacturer. On the contrary, the production process ratio of larger particles will result in smaller refractory plastics than those with smaller particles. Plastic lasts longer.
