Complimentary Slide Rule ca. 1976

Check Out the Yield Auditor for Heat Seal Pass Through: Roll on Top / Roll on Bottom

Single Roll Cutoff with Wand

If you are shrink wrapping cases, you are a converter. You buy film by the kilogram and cut it off into sleeves before it goes into the shrink tunnel. If you buy 55.88 cm X 50.8 μm sheeting and have one ply on top & bottom, for practical purposes, you are making a bag. Multiply the weight per 1,000 packages by the price per kilogram to derive the cost per 1,000 cases. If you cutoff one sheet at a time – simple. Just imagine a bag by folding either the width or length of the cutoff so there are two plys. Example:

• 55.88 cm
• 50.8 μm (micrometer / micron) (ostensibly)
• 86.36 cutoff

Half of the web width or ½ of 55.88: 27.94 cm X 86.36 cm X 50.8 μm÷.0001849 = 22.66 kg / 1,000 packages Half of the web cutoff or ½ of 86.36: 43.18 cm X 55.88 cm X 50.8 μm ÷.0001849 = 22.66 kg / 1,000 packages Example: Here is an example of film which is 7% “heavy” and well within the ± 10% industry tolerances. However, the film is produced “heavy” adding cost to the packages without the customer realizing the additional cost:

• 55.88 cm
• 50.8 μm (micrometer / micron) (ostensibly)
• 40.64 cm od rolls
• 34.93 kg per roll
• No footage marked on roll tags
• one roll cutoff style
• 86.36 cutoff
• 1,443 packages from 1 roll of film @ 34.93 kg per roll

Step 1	measured cutoff = 55.88 cm
Step 2	1,443 packages from 1 roll of film
Step 3	weight per 1,000 packages = 22.66 kg / 1,000
Step 4	34.93 kg ÷ 22.66 kg /1,000 = 1541 “theoretical yield” from 34.93 kg film
Step 5	compare actual (1,443) to theoretical (1,541)

In this example, the real cost per 1,000,000 cases assuming a price of $1 per pound is $53,350 not $49,860.