In pharmaceutical industry tablet tooling means upper punch, lower punch, and die of a compression machine. They are essential tools to shape any granules or powder into a solid dosage form by applying compression force.
Types of Tablet Tooling
Types of tablet tooling are mentioned in below table with detail information -
A Drawing of Upper punch and Lower punch
Common Tooling Terminology
Head: The head is the end part of a punch that guides it
through the cam track of the compression machine.
Head flat: The flat portion of the head which makes contact
with the pressure rollers and determines the maximum dwell time for
compression.
Working length: The dimension from the head flat to the lowest
measurable point of the tip face, responsible for the consistency of the tablet
overall thickness.
Punch overall
length: The total length of a
punch, other than flat-face tablet configurations, that is normally a reference
dimension which consists of a combination of the working length and the cup
depth dimensions.
Cup depth: The depth of the cup from the highest point of the
tip edge to the lowest point of the cavity.
Die:A component used in conjunction with the upper and
lower punches; it accepts the product for compaction and is responsible for the
tablet’s perimeter size and configuration.
Die bore: The cavity of a die that accepts the product for
compaction and determines the tablets size and shape configuration.
Die taper: A gradual increase in dimension, starting from a
given depth in the die bore and increasing to the die chamfer; used normally to
release air from the die cavity during the compression cycle.
Barrel: Guides the punch while traveling of punches (going
up and down).
Cleaning of Tablet Tooling
Keeping tools clean can decrease premature tool wear
and allow lubrication to be more effective as well as reduce the possibility of
product cross-contamination.Dirty tooling may cause binding, which can damage
tooling and tablet presses.
Method-1:The optimum procedure that meets this criterion is
ultrasonic cleaning with an automatic dryer. Ultrasonic cleaning provides the
tooling with increased exposure to the cleaning solution without the risk of
damage, critical for hard-to-reach portions of the punch, such as the keys and
embossing. The advantage of using a dryer in conjunction with an ultrasonic
cleaner is that it eliminates the potential for surface corrosion and
discoloration.
Method-2:Use 0.1% teepol solution with purified water for
cleaning after the use of punches and dies, also can use a soft plastic
scrubber if required. But do not use a metal scrubber; it will make scratches
and marks, roughness on punches, and die.
After cleaning, intimate to QA department for rinse
water or swab sample to QC for testing for a residual trace of detergent and
previous product (Method and cycle of cleaning of punches and dies shall be
validated).
Use oil-free filtered compressed air and a suitable
dry clean duster for the dry. After cleaning and drying, the disinfection of
punches can be done by wiping with 70% isopropyl alcohol.
Lubrication of Tablet Tooling
For proper storage and maintenance of tablet tooling
lubrication is required. Lubrication is done by using food-grade oil like
castor oil or liquid paraffin, but there is a problem with the rancidity of
oil. So nowadays, various synthetic lubricants and grease are available, which
have been now used in most pharmaceutical companies.
Sources:
- Pharma Manufacturing Guidelines
- Pharma Approach
- Natoli