Calculator
Tablet coating weight gain calculator
How much dry coating material a batch needs at a target percentage weight gain, including process loss.
Result
- Dry coating applied
- 1.35 kgWhat ends up on the tablets
- Material to issue
- 1.553 kgIncludes 15% process loss
- Tablets in the charge
- 90,000
- Coating per tablet
- 15 mg
- Coated tablet weight
- 515 mg
Formula
dry coating (kg) = charge (kg) × weight gain (%) ÷ 100 material to issue = dry coating × (1 + process loss ÷ 100)
Why this number matters
Weight gain is how a coating run is specified and how it is signed off. You weigh the charge in, coat until the tablets have picked up the target percentage, and stop. Everything else, spray rate, pan speed, bed temperature, exists to get you there without a defect. The figure that matters on the shop floor is the second one, because you have to issue more material than ends up on the tablet.
Where it goes wrong
Process loss varies with pan design, spray gun setup and how well the run is controlled. Fifteen percent is a reasonable planning figure for a first trial, and your own runs will give you a better one within two or three batches.
Other calculators
Every grade page carries the process parameters it was developed on, so you can start from a known point rather than a calculated one. Browse the grades.