Scaling up the coating process Various articles on scale-up
principles have been published (1–3). The following are basic
scale-up principles that can be applied easily in practice: -
Batch size scale-up is largely dependent on the pan size. As a
general rule, the bed depth in proportion to the pan depth
should be kept constant. This proportion will help to achieve
consistent tablet flow in the scale-up batch, assuming the pans
have similar dimensions. However, the technique can also be
useful even if the pans are not geometrically similar. - Pan RPM
scale-up is based on the industry's accepted principle of using
the linear distance travelled by tablets in the pan per unit
time as constant, and can be applied to obtain similar dynamic
conditions during scale-up. The linear distance is calculated as
πD, where D is the pan diameter. Using this principle, the
following calculation will provide the pan RPM: - Air flow
scale-up. Air flow is frequently limited by the particular
equipment and/or blowers installed on