Shrink Wraps Basics
Shrink wraps, also shrink film, is a material made up of polymer plastic film. When heat is applied, it shrinks tightly over whatever it is covering. Heat can be applied with a hand held heat gun (electric or gas) or the product and film can pass through a heat tunnel on a conveyor.
Most commonly used shrink wraps are made of PVC (Polyvinyl Chloride), POF (Polyolefin) and LDPE (Low Density Polyethylene). They are available in a variety of thicknesses, clarities, strengths and shrink ratios.
Shrink Wraps Usage
Shrink wraps are applied over or around the intended item, often by automated equipment. It is then heated by a heat gun or sent through a shrink tunnel or oven for shrinking.
Heat Shrink Tunnel
Shrink wraps can be supplied in several forms. Flat roll stock can be wrapped around a product, often with heat sealing to tack the film together. Center folded film is supplied on a roll with the plastic is folded in half. Product is placed in the center portion, the remaining three edges are sealed to form a bag, and the package then heated which causes the bag to shrink and conform to the product placed in the bag. Pre-formed shrink bags plastic bags are used with one end open. The product is placed in the bag, sealed, and sent for heat shrinking.
Shrink wraps can be used to wrap buildings. It can wrap roofs after hurricanes, earthquakes, tornadoes and other disasters. Shrink wrap can be used for environmental containments to facilitate safe removal of asbestos, lead and other hazards.
Shrink wraps are also used to wrap up books, especially adult-oriented ones and certain comics and manga, mainly to prevent them from being read by minors.
Software on carriers such as CDs or DVDs are often sold in boxes that are packaged in shrink wrap. The licenses of such software are typically put inside the boxes, making it impossible to read them before purchasing. This has raised questions about the validity of such shrink wrap licenses.
Heat Shrink Gun
Shrink wraps are commonly used as an over-wrap on many types of packaging, including cartons, boxes, beverage cans and pallet loads. A variety of products may be enclosed in shrink wrap to stabilize the products, unitize them, keep them clean or add tamper resistance. It can be the primary covering for some foods such as cheese, meats,vegetables and plants. Heat-shrink tubing is used to seal electric wiring.
Shrink bands are applied over parts of packages for tamper resistance or labels. It can also combine two packages or parts.
Shrink wraps are also commonly used within more industrial applications using a heavier weight shrink film. The principles remain the same with a heat shrinking process using a hand held heat gun.
Below are the demonstration videos of how shrink wraps are used for wrapping materials.