Calculating the consumption of polymer

What Is It?
A simple calculation that tells you the consumption of poly(ethylene terephthalate), PET by an injection molding machine.

The Calculation Is...

kg / hr = W x C x S

Where;
W = Weight of the container in kg. (e.g. 45 grams = 0.045 kg)
C = Number of injection cavities
S = Number of injection cycles per hour (shots)
(3,600 / Cycle Time (sec) for one set of preforms)

Example

A machine with a cycle time of 14 seconds making a 35 gram bottle
W = 0.035
C = 8
S = (3,600 / 14) = 257.1
kg / hr = 0.035 x 8 x 257.1 = 72 kg / hr

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