What are the main similarities and differences between the open mill and the internal mixer?

The open mill is a double-roll machine, which uses two rolls with different relative movements at different speeds to generate shear force for mastication. The operation is to continuously carry out the operation of playing triangle bag.
The mixer uses the regular contraction of the space generated by the relative movement of the internal designed blades to generate shear force.
The structure of the mill is simple and the cost is low, but the labor intensity is high, the pollution is large, and the physical harm to the workers is great.
Internal mixers are more expensive, but they can be heated, vacuumed, and pressurized internal mixers can be used to process difficult-to-plasticize materials. The labor intensity is low and the adaptability is strong.
The mixing amount of the open mixer is small, and the various matching doses are easy to add. Moreover, because it is open, the heat dissipation is fast, and the temperature influence is not so obvious. Moreover, if the temperature is felt to be relatively high, the mixer can be stopped for a period of time and allowed to cool before mixing. However, the one-time mixing of the internal mixer may be several times that of the open mixer. During the mixing process, the temperature change needs to be strictly controlled and the addition order of small materials must be controlled, these will affect the uniformity of mixing and scorching; and the discharge temperature must be strictly controlled. The temperature in the mixer is very different from the temperature of the rubber compound. Therefore, the relationship between this temperature must be considered when controlling the temperature, otherwise the rubber compound is easy to scorch (generally, the internal temperature of the rubber compound is 50-60 degrees higher than the internal temperature of the machine).