1) First of all, the quality of pure tablet must be cleared.
The coating solution is 85G-Colorcon. The distance between the spray gun and the pan is 25cm, the temperature of the tablet is 40 degrees Celsius, and the speed is 18r/min. The cone angle is the largest, and the flow and atomization have no specific parameters.
When coated, slowly flow 1H slowly, then increase the flow capacity of 2H and increase the weight by 4%.
2) The problem of compressed air: the pressure of coating is generally adjusted to 0.2 to 0.3Mpa enough.
3)Coating over the baffle design issues: cut three peristaltic pumps on the silicone hose, 120 degrees of angle will be the inner wall of the coating pot three-way separation, paste with transparent glue can ah, very convenient, cleaning can be completely torn down to clean, replace the diameter of the silicone hose can adapt to different amount of coating, coating more silicone tube The diameter can be increased properly. Each feeding 1.3 kg or so, with the outer diameter of 8 mm silica gel tube, pot body speed frequency of about 15 HZ can achieve effective roll sheet bed!
4) Pot rotational speed: Pot rotational speed has no unified provisions, but experience can be in the process of rotating the pot bed to obtain a stable flow section can be, the more general feeding as 2 kg feeding, rotational speed can be lower (generally 10-15 Hz can be), feeding less as 0.6 kg, rotational speed should be faster.
4)Spraying speed: peristaltic pump must be good, do not believe that the coating machine instructions do not need peristaltic pump, the general frequency of peristaltic pump spraying control in 3-4 Hz can be, if the amount of feeding more, in the premise of guaranteeing non-sticking slices can properly increase the frequency of peristaltic pump.
6) Spray gun position problem: I think that small batch film coating needn't use a ruler to measure the distance between the spray gun and the core section, mainly depends on whether there will be spray drying phenomenon in the coating process. Once the distance is too wide, the dust will suddenly increase a lot after spray drying. At this time, the position of the spray gun can be reduced appropriately, experience the operation. The method is to strand the compressed air pipe and the feeding pipe together, then tie the support rod of the spray gun with transparent glue or strap, and then start coating, the air inlet nozzle is pressed against the connection of the compressed air pipe and the support rod to fix the position of the spray gun, and the hot air enters the way just in the slice core section, the drying effect is best.
7)Sheet bed temperature problem: Because the machine can not control the inlet air temperature, I generally test the temperature of the sheet bed, the coating process will first put the core into the coating, with a low speed (such as 10 hz) preheating 5-10 minutes, insert the thermometer into the sheet bed, the general test temperature is about 55 degrees Celsius when you can start coating, if peristaltic pump frequency For 4Hz, the stable bed temperature can be controlled at around 38~45 degrees Celsius.
8) Vacuum problems: because there is no vacuum device, another blower, in the process of coating, if there is more subdivision in the pot, can be blown several times with a blower, if a large amount of dust, it is necessary to consider the position of the lance, it is best to reduce properly.
9) Coating time: 1 kg feeding, according to the above parameters in general 40-60 minutes to complete the weight gain of 3% - 4% coating effect, the more the core of the longer time, if only 0.5 kg feeding, spraying time only takes about 30 minutes;
10)Coating sheet polishing problem: after the end of the spraying, can properly reduce the rotational speed, continue to heat the air sheet bed temperature to 55 degrees Celsius (measured by thermometer), that is, play a dry moisture, but also through the friction between the sheets, grinding the burrs on the flat surface, play a polishing role, of course, the effect is far from larger efficient The gloss ratio of the coating pot is better than that of the coating pot, but the gloss improvement is very obvious.
After drying, don't forget to cool the core to room temperature and then pack it, otherwise it will be moist and sticky, and it will be worthless. If you need to put the cold quickly, you can use the air cooler to cool down, and the result is good.