Measuring A Poly Bag & Minimum Flexible Packaging Order Quantity

When writing the size of a plastic bag, the FIRST measurement listed is always the width across the open end. The second measurement is the side gusset, if any, then the length from the open end to the closed end and the last size dimension is the bottom gusset, if any. Please note that the side gusset and the bottom gusset are mutually exclusive....one cannot exist with the other present. A side gusset is always smaller than the lay flat width of the bag. The final measurement that must be known to produce an accurate plastic bag quote is the thickness. All plastic film used by Custom Poly Packaging to produce poly bags is unsupported (conforms to objects, flexible) and has a thickness measured in thousandths of an inch.

The flexible packaging "industry standard" is to manufacture plastic bags with an actual thickness of 10% less than the thickness requested by the customer. We refer to this lighter film gauge as a "nominal thickness". Thus, .002 nominal thickness is an actual measured thickness of .0018.

For competitive pricing when requesting a quote, please inform Custom Poly Packaging whether the thickness requested is the actual (full gauge) measurement or nominal.

Here are some examples of measurements for flexible packaging bags made by Custom Poly Packaging from unsupported Low Density Polyethylene, High Density Polyethylene or Polypropylene films:

• Flat poly bag 12x18 .002 nominal = 12 wide across opening x 18 long .0018" thick film.
• Side gusset poly bag 8 wide x 4 side gusset x 20 long .00225" thick film.
• Bottom gusset poly bag 10 wide x 15 long x 4 bottom gusset .0017" thick film.

These bag styles are always written in this manner.  Note that the side gusset cannot be larger than the lay flat width and the bottom gusset cannot be bigger than the length.

When requesting a quote on a new poly bag, having the dimensions of the bag or the dimensions of the item(s) that will be packaged will help facilitate the quoting process. Items to be packaged in a poly bag can have large variances in density. Unfortunately, to ask for a quote on a "12 oz" bag is not enough information to calculate the dimensions of the bag. We must know the physical measurements of the volume (width, diameter, length, height) to calculate the size of the bag required.

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