Shrink wrapping sizing, also known as package sizing, is the process of calculating the appropriate size film for wrapping a specific package in packaging shrink film. Many factors must be considered when sizing film in order to ultimately obtain the optimum size for your application and product. The actual product size, the orientation of the package in the film and the type of shrink wrap equipment to be used are all necessary information. Incorrect dimensions, missing data or failure to obtain this information or incorrect specifications may result in the calculation of an inappropriate film size.
Each individual package has three specific dimensions that determine the width of the base film. These measurements should be taken according to the orientation (positioning) of the package as it enters the film.
Position the package by using the shortest possible dimensions in the case of centre fold use or side seal applications, as the product length generates the least amount of waste.
The shorter the product length, the faster the product cycles in and out of the sealing area. This increased time saving can yield huge dividends during production transfer.
Although the product will require the same square inch of film regardless of orientation, the amount of waste generated will be reduced.
Another consideration when recommending packaging shrink film sizes is the speed of production. In many cases, the formula used to calculate the required film size is not a whole number. Although 1/2 inch increments can be used, most users choose the standard inch size and we strongly recommend that you round the size up to the next inch mark rather than rounding down. Using a film that is too narrow can negatively impact machine operation and production speed, as well as increase your overall packaging costs.
Once you have determined the orientation and size of the package, the next thing to consider is the type of equipment that will be used to pack the package. The particular type of equipment determines whether to use a centrefold or a single roll of film. In addition, certain types of machines require the use of wider film sizes than others due to their operating mechanisms.
When using the packaging shrink film sizing formula to calculate film sizes, always use the formula applicable to the type of equipment.