For small tablet presses, various problems will occur during use, so how to reduce or prevent surface defects of tablet presses?
(1) Prevent and control the variegation of the material itself. Due to imperfect granulation and drying process, or inadequate cleaning of mixing and conveying equipment, it is easy to generate mixed-colored material granules.
(2) Prevent chemical reaction of materials. Some parts of the tablet press that are in direct contact with the material, such as the feeding substrate, scraper plate, powder collecting ring, scraper and stopper, are often made of corrosion-resistant bronze materials.
For special formula materials that are prone to chemical reaction with copper parts and cause discoloration, the material of the relevant parts should be replaced with austenitic stainless steel with more stable performance before the test piece.
(3) Prevent material from friction and heat discoloration. The high-speed rotating turntable of the tablet press moves relative to the parts in contact with the material, such as the substrate and the quantitative scraper of the feeding system, and forms mutual friction through the material medium.
When the generated heat value exceeds the melting point of the material, the material will be oxidized and discolored, resulting in black or color spots on the tablet, especially for heat-sensitive or low-melting materials.
At this time, the gap adjustment and other work should be carefully done: the gap between the bottom surface of the feeding substrate and the working end face of the turntable should be slightly enlarged and adjusted to the upper limit based on the principle of not running powder;
the adhesion force between the scraper and the working end face of the turntable It should not be too large, but it should be tightly fitted when it is dynamic; reduce the contact area between the parts in contact with the material and the rotary table, and reduce the probability of frictional heat generation.
After the adjustment, the tablet should be tested to verify whether there is any discoloration of the material, and then it can be transferred to mass production to ensure that there is no problem.
(4) Prevent and control materials or tablets from being contaminated by the lubricating oil of the main engine. If the main engine lubricating oil is excessive or the equipment is not properly managed, it is easy to cause the main engine lubricating oil to contaminate the material or attack the tablet, resulting in black spots or color spot surface defects. To this end, the following work should be done: control the oil supply of the lubrication system.
The tablet press manufacturer adjusts to shorten the oil supply time (lubrication time) of the lubrication system, and the tablet press manufacturer reduces the oil supply interval (lubrication interval).
Laboratory tablet presses, such as the dust-proof sealing ring and oil collecting ring of the punch, the dust-proof sealing ring of the feeder, etc.; strictly implement the cleaning procedures of the tablet press. When continuous production for a long time, even the same batch of drugs, still It is necessary to do regular cleaning.
The above is the industry sharing about tablet presses, I hope everyone can like it.