Compression machine sound

In one of the our Trial containing herbal ingredients we find that during the compression the machines makes a very loud sound indicating the high pressure of the machine.
I want to know what are the different possible reasons for this sounds.
I cross check with calcium granules and the tablets compressed were of proper hardness without any sound of the machine.
Please comment.


Machine sound may varry product to product.
usually sound increase in following
over pressure
extra moisture
low lubrication in formulation

We are also not getting proper hardness of tablet
Granules final sifted from 20# sieve.
Compress at 10 mm round standard concave punch both side plain.
Please comment

check the moisture level

tab weight?

conduct a trial by slugging.

Moisture content =2.5
Tablet Avg Wt =350mg

Already conducted but not fruitful

What about optimum granule size for 10 mm punch for more hardness.
means which no of sieve we will use

weting is by IPA or water?

usually 16 no sieve


try to change sieve 16 no then 12 no

how much hardness is obtainef?

We are using 20 # sieve and get less than 4 kg/cm2 hardness

try to conduct trial with 16 no and 12 no sieve.

which type of comp machine using?

also check hardnes of 20 no grains by releasing pressure down.some product at high pressure does not give high hardness due to overload and sliping action and give good hardness by decreasing pressure.

16 station D tool compression machine

D type is good.problem is with formulation.try to change sieve