mixing arm
The mixing arm is a central structural element of the powder mixer. It is firmly connected to the mixing shaft. This connection can be bolted or welded. Its primary task is to support the mixing tool. This tool sweeps over the wall of the mixing chamber at a defined distance.
In many applications, the mixing arm performs additional functions. It can be designed to optimise flow. In this case, it actively influences the movement of the material being mixed. The aim is to generate specific product flows. These flows improve the mixing process and reduce mixing time.
In certain designs, the mixing arm fulfils an additional function. In amixon® contact dryers, the mixer arms can be double-walled. A thermal fluid flows through the cavity. This allows heat to be transferred to or from the product during mixing. The mixing arm thus becomes part of the mixer's thermal system.
Mixing arms are very important in terms of safety. They must have high dimensional stability. Only very slight elastic deformation may occur under load. This is particularly relevant for moist, viscoplastic or highly viscous mixing materials. In these cases, high forces act on the mixing arm and the mixing tool.
Even under maximum load conditions, there must be no contact between the mixing tool and the mixing chamber wall. A safety-relevant load condition theoretically occurs when the mixing tool is blocked in the mixture and the mixer drive is started. However, this operating condition is avoided in practice. It can, however, be clearly described mathematically.
The forces acting on the mixing arm can be calculated from the maximum transferable drive torque. Based on this, the elastic deformation is calculated. This calculation is part of the structural design.
Abrasive or wearing mixing materials subject the mixing arm and mixing tool to increased stress. Their condition must therefore be checked regularly. This ensures operational safety and maintains mixing quality.