A double helical cone mixer relies on two asymmetric cantilever screws inside a conical vessel. One screw is long, the other is short. Their combined motion creates a gentle but thorough mixing action that suits many powder and powder-liquid blends. Hansheng Automation machines mixer screws, drive shafts, and wear components to customer drawings when parts need replacement or modification.
Motion of the Mixing Elements
Self-Rotation and Planetary Revolution
The mixing elements are two asymmetric cantilever screws. Each screw rotates around its own axis while also moving around the central axis of the cone. A rotating arm carries the screws along the inner wall in a planetary path. This combination of self-rotation and revolution applies several forces to the material at once, so the batch is never static.
How the Two Screws Divide the Work
The long screw lifts material from the bottom of the cone toward the top. The short screw takes a larger role in dispersing and blending material in the upper and middle zones. Because the two screws are asymmetric, the material follows different paths depending on where it sits in the cone. That difference is what drives exchange between layers.
How Material Moves Inside the Cone
Lifting and Dispersion
The screws lift material repeatedly from the bottom to the top of the cone. As material rises, gravity pulls it back down along the screw flight surface. This creates a convection current that keeps the batch circulating. The long screw feeds the upper zone; the short screw spreads material into the surrounding bulk.
Shear and Diffusion
The screws also apply shear as they push material through the cone. This shear helps break up agglomerates and spreads minor ingredients into the main bulk. At the same time, the revolving motion of the screws produces diffusion, which speeds the batch toward uniform condition. Shear and diffusion work together rather than in sequence.
Combined Motion
Self-rotation, revolution, lifting, shear, and diffusion form a combined motion pattern inside the cone. Material in the center, near the wall, and at different heights all follow different paths, so the batch exchanges positions continuously. The result is a uniform blend without the intense impact found in high-speed paddle mixers.
Applications and Characteristics
Wide Material Adaptability
The double helical cone mixer handles materials with large differences in specific gravity and particle size. It does not cause segregation during mixing. This makes it useful for formulas that combine heavy and light ingredients in one batch.
Gentle Mixing
Mixing is gentle and does not crush or compact particles. This matters when the material must keep its original particle shape or when fragile granules are part of the formula.
Heat-Sensitive Materials
The mixer avoids local overheating. Its motion pattern and the exposed cone surface help dissipate heat, so heat-sensitive ingredients are less likely to degrade during the cycle.
Liquid Addition and Spraying
In powder-to-powder blending, liquid can be added easily. One or more spray nozzles can be fitted to meet specific process requirements. This supports formulas that need a small amount of liquid binder or coating agent.
Discharge
The bottom of the cone uses an offset valve for discharge. Material leaves the mixer without compaction, and the cone shape helps the batch flow out under gravity. The discharge path should be checked during maintenance to keep the valve seating clean and the outlet free of buildup.
Practical Notes
Match batch size to the working volume of the cone, and set screw speed according to bulk density and flowability. Check screw flight wear, shaft seals, and the discharge valve on a regular schedule. If the application calls for tighter clearance or a different screw profile, we can machine replacement screws and shafts to drawing.
Our precision custom machining capability is not limited to cone mixers. Hansheng Automation also produces parts for medical devices, printing machinery, and filling machinery, along with precision components for yachts and RC cars. From one-off parts to small batch runs, we machine to customer drawings and deliver parts ready for assembly.
