How To Shrink Wrap
Shrink wrapping products for retail sales can be a great option for business owners seeking a professional packaging option at an affordable price. Many people know that shrink wrap is a plastic that shrinks down and conforms to what it is wrapped around, but are not aware of the shrink wrapping process.
We believe it is important for any business owner to be informed about business decisions to be able to make the right business decision. We have a lot of useful content online about shrink wrapping to help make those decisions. Until now, we have never had a page dedicated on how to shrink wrap.
Before we get started, here are some useful resources that can assist in learning about shrink wrap packaging. We have two different blogs that offer useful information about shrink wrapping. One of our blogs is our onsite blog that discusses a variety of packaging options including shrink wrapping. Our other blog is an offsite blog that has years of compiled information broken into categories. The shrink wrap category offers dozens of posts about shrink wrap materials, machines, and processes. The last resource we recommend is our shrink film 101 page. This is a beginners guide to shrink wrapping. All of these resources have small sections about "how to shrink wrap" and we will refer to them throughout this page as well as videos and other picture diagrams. So let's get started.
Step One - Determining Equipment
Professionally shrink wrapping products requires three key elements. The type of shrink film to be used, a heat sealer to seal open ends of the material, and a heating element to heat the film so it will shrink and conform to the product. There are a few applications, such as gift basket shrink bags and some shrink tubing applications that do not require a heat sealer. The majority of shrink wrapping applications do require all of the elements listed above. Below is a brief breakdown of each.
Shrink film is primarily made from four types of plastics: Polyolefin, PVC, Polyethylene, and Polypropylene. Each type of material offers different characteristics, advantages, and disadvantages. Polypropylene shrink wrap is the least common, the other three types of shrink films are very common for different industries and products. This blog post helps to describe the differences and characteristics of each type of film.
Once the type of shrink wrap is established, users should consider the form of shrink film they will use. Shrink film can come in tubing, bags, centerfold rolls, and single wound (flat) rolls. Here is a complete list of shrink wrap products including different forms of shrink film available.
We have several articles about the types of sealers available on the market. The cost of a sealer is directly related to the seal width and the desired levels of production. A small four inch hand sealer is much less expensive than a large 24"x32" L-Bar sealer. Our guide to shrink wrap machine costs will help determine what type of sealers to consider.
The heating element applies heat to the shrink film after the open ends have been sealed. The heat shrinks the film to conform to the products being packaged. The two primary forms of heating elements are heat guns and shrink tunnels. A heat gun is a fraction of the cost compared to a heat tunnel, but also offer only a fraction of the efficiency. Our guide to shrink wrap machine costs referenced above details the benefits and costs of shrink tunnels and heat guns.
Step Two - Proper Measurements
Proper measurements will help determine the size and form of shrink film to consider, the size of sealer needed, and the size of shrink tunnel if needed. We recommend length x width x height measurements of the largest product being wrapped. Purchasing shrink film, a heat sealer, and a shrink tunnel to accommodate the largest product will enable the ability to wrap smaller products as well.
Depending on production levels, using a couple different sizes of film can reduce waste and cost. If you you are wrapping a wide range of product sizes, multiple rolls of centerfold film may be beneficial. If using shrink bags multiple sizes and proper product measurements are essential. The same is true for tubing when wrapping products of different sizes.
How To Measure
To measure for shrink film the best option is to measure the circumference and length of each product. The circumference measurement is the measurement around the product at the widest point.
Formula For Centerfold Shrink Film
Width + Depth + 2 Inches = Width of Roll Needed
Formula For Shrink Tubing
Circumference + 10% / 2 = Width of Tubing Needed
Formula For Shrink Bags
Circumference + 10% / 2 = Width of Bag Needed
Length + Depth + 2 Inches = Length of Bag Needed
Step Three - Sealing Open Ends
Once measurements and proper film sizes are determined, the rest is easy. Place the product in the film roll, bag, or tubing. Close the sealing bar on the open ends of the film approximately half an inch from the product and make seals. If using an I-Bar sealer with centerfold film, seal one side, rotate the product and seal the remaining open sides. An L-Bar Sealer will seal both open sides with one seal. The excess film should be easily removed after the seal is made.
Step Four - Apply Heat
Once open ends are sealed, apply heat with shrink gun or shrink tunnel. If the film balloons and fills with air when heat is applied, a small vent hole may be required to allow air to escape.