Melt Delivery Tube Geometry Influence on Atomization Vacuum Aspirator Pressure
Melt delivery tube setback and tip taper dictate atomization aspirator pressure, where sub-atmospheric suction prevents melt freeze-off and backpressure blowback.
Concentricity Alignment Tolerance
Meaning
The allowable deviation between the central axis of the liquid delivery tube and the central axis of the gas nozzle determines the uniformity of energy transfer during atomization. Maintaining a tight concentricity alignment tolerance ensures that the high-velocity gas flows symmetrically around the metal stream.
Flow Asymmetry
Misalignment between the gas and liquid orifices creates a lopsided pressure field that destabilizes the spray pattern. When the concentricity alignment tolerance is exceeded, the primary gas jet strikes one side of the liquid column with greater force than the other. This imbalance generates a non-uniform droplet distribution and increases the yield of coarse, out-of-specification powder.
Process Reliability
Frequent nozzle clogging and localized material buildup often occur when the alignment of the system is out of specification. If the concentricity alignment tolerance is poorly managed, the deflected liquid stream can contact the metal rim of the nozzle assembly. This contact leads to immediate solidification, a phenomenon that forces an unscheduled shutdown to clear the blockage.
Rigid mounting brackets and precise machining are critical to maintaining the necessary alignment during assembly.
Quality Control
Advanced optical measurement systems verify the alignment before starting a production run. Maintaining the concentricity alignment tolerance secures the symmetry of the atomized spray.