Although the main structure of a powder packaging machine may look similar to that of a liquid filling machine, the feeding principles are fundamentally different, so they cannot be used interchangeably.
Powder packaging machines mainly use a screw feeding method. A rotating screw shaft pushes powder material forward to achieve metering and filling. This method is suitable for powder or granular materials with poor flowability or a tendency to bridge, but it cannot effectively convey liquids. Liquid tends to flow back through the screw clearance, making stable metering impossible.
Liquid filling machines rely on pumping or extrusion principles, using pistons, peristaltic pumps, diaphragm pumps, or other mechanisms to press liquid into containers. The flow behavior of liquids is completely different from that of powders, requiring valve bodies and pipelines with higher sealing performance, as well as measures to prevent dripping and splashing.
If liquid is directly introduced into the screw feeding system of a powder packaging machine, accurate metering cannot be achieved. In addition, liquid may penetrate transmission parts, causing corrosion, seal failure, or reduced metering accuracy.
Therefore, powder packaging machines and liquid filling machines must be designed separately in terms of feeding mechanisms, sealing structures, and metering methods. If users want the same main machine to switch between different materials, the feeding components and seals usually need to be replaced. For such non-standard screw shafts, filling nozzles, adapter flanges, and seals, Hansheng Automation provides custom machining based on customer drawings, supporting material selection and tolerance control to help the equipment adapt to specific materials.
