A tablet coating machine applies coating materials to tablet surfaces through controlled spraying, tumbling, drying, and polishing processes. During traditional sugar coating, syrup and coating suspension are added to the tablet pan in multiple stages. As the pan rotates clockwise, the tablets continuously tumble, slide, and rub against each other. At the same time, hot air is introduced to remove surface moisture, helping form a uniform coating layer and achieve the required polishing effect.
Structural Features of Tablet Coating Machines
1. Coating Pan Design
The coating pan is designed to provide a suitable material-flow pattern during operation. Proper tablet movement helps maintain uniform coating-layer thickness, consistent color, and a smooth surface while reducing defects such as pitting and uneven coating.
2. Drive and Rotation System
The machine typically operates with continuous low-speed rotation in a single direction. The main motor works together with a reduction gearbox to drive the coating pan smoothly and reliably.
The gearbox is designed for stable long-term operation, and a fully enclosed oil-bath lubrication system can help provide reliable lubrication for the transmission components while reducing the risk of lubricant contamination.
3. Hot-Air Drying System
The drying system uses electric heating elements to generate hot air for removing moisture from the tablet surface. Stable and evenly distributed airflow helps accelerate drying and supports the formation of a consistent sugar-coating layer.
The actual air temperature and airflow should be adjusted according to the coating formulation, tablet characteristics, and process requirements.
4. Coating Liquid Supply and Spray System
The coating-liquid supply system is designed for straightforward operation. In basic configurations, the coating liquid can flow from a higher position to a lower position under gravity. For more controlled spraying, an atomizing spray gun can be used to distribute the coating solution evenly over the tablets.
A properly selected spray gun helps improve atomization, spray coverage, and coating uniformity. The spray rate, spray angle, and spray pattern can also be adjusted according to different coating processes.
For pharmaceutical equipment manufacturers, the performance of the coating system also depends on the precision of its mechanical components. Hansheng Automation can manufacture custom precision components for tablet coating machines according to customer drawings and technical specifications, including shafts, bushings, supports, spray-system parts, connectors, and other non-standard components.
We support made-to-drawing machining for prototype and small-batch production, with machining processes selected according to the required material, dimensions, tolerances, surface finish, and actual operating conditions.
