The end-user of shrink wrap purchases the product by means of roll cost. A roll of 60 gauge shrink wrap costs $XX.xx. Oftentimes, people like to be aware of how much the amount of shrink wrap on each package is costing them.
For example; A small manufacturer is overwrapping his product on a manual L-bar sealer. His current supplier has recommend he use 8″ centerfold film in a 60 ga. material.
- The dimensions of his package are 2″ tall x 4″ x 8″.
- Obviously, he is wrapping his package by orientating it with the 8″ side in the machine direction. In doing so, each cycle is producing a scrap tail 11″ long by approximately 2″. That calculates out to 22 sq.inches of scrap per package. (2 layers of scrap, 1″ wide. Centerfold!)
- Industry standard put-up is 4370 feet of shrink wrap per roll. That equates to 52,440 inches in length. (Feet x 12 = number of inches)
- Dividing 52,440 by 11 ( bag length or cut-off) equals 4767. That is the maximum number of packages obtained from each roll of shrink wrap.
- Dividing the price paid per roll of shrink wrap by 4767 determines the cost per package.
- Remember that 22 sq.in. of shrink wrap wasted each cycle? Multiplied by 4767 (total # of packages per roll) the total amount of wasted material is 104,874 sq.inches.
- In the case of an 8″ centerfold, a roll with a total area of 839,040 sq.inches, his current scrap waste is 12.5% of the total amount of shrink wrap purchased!
- Lets re-orientate this package and check the savings.
- Turning the package 900 results in the need of 12″ shrink wrap. The cut-off, however is reduced to 7″ That results in a total waste of 14 sq. inches of film per package. The net result is 35% less scrap!
With the new situation, the total amount of scrap generated equals 8% of shrink wrap purchased. By simply turning the product, this shrink wrap customer has saved 4% per roll. In addition to the savings, this shrink wrap customer will benefit a higher package yield from a single roll (7491 pkgs / per roll) and increased production speed. (The new package is 35% shorter than the old method allowing faster through-put.)