Lightweight insulating castables play a role in heat preservation. If used in pipelines, the body density cannot be lower than 1.2 kg/m3 under normal circumstances. The specific gravity of 1.5 is more commonly used. However, when used in pipelines, the construction process will be subject to certain restrictions due to the limitation of the pipeline diameter, because it is not easy for construction workers to construct in the pipeline.
Matters needing attention first are: the insulation layer part, the pasting of thermal insulation cotton is also a part that is not easy to implement. If the pipeline insulation is extremely irregular, and the anchor is not suitable for use, the anchor must be painted. If it is not painted, a plastic cap must be put on the anchor. Otherwise, it is easy to rust and affect the service life. If this happens, there is a certain way to remedy it, that is, to lay a layer of plastic film on the surface of the insulation cotton. In this way, after the Lightweight insulating castables is constructed, the moisture during baking is not easy to penetrate into the insulation. If the moisture penetrates into the insulation cotton, even if it is used after drying, the effect of the insulation cotton will shorten the service life.
Another thing to note: When constructing lightweight materials, you must pay attention to the proportion of addition, because if too little water is added to the lightweight castable, some of the raw materials in the matrix are too light to be constructed and not easy to condense. If too much water is added, it will affect the strength of later use.
Therefore, during the on-site construction process, the aggregate and powder should be mixed first, then the binder should be added, and then the lightweight castable should be added and stirred in strict accordance with the water addition ratio given by the manufacturer. After stirring, see that its fluidity is intact, and then vibrate the construction. Under normal circumstances, the amount of water added to the Lightweight insulating castables is 15-17%. Some manufacturers will also sprinkle some water to facilitate production control due to the light weight of the lightweight castable during production.
