What are vacuum formable plastic sheets and the process behind them?
Vacuum formable plastic sheets are made of poly vinyl chloride (PVC), an affordable and extremely strong manufacturing product. As a result, it offers superior impact resistance, high stiffness and durability, not to mention cost-effectiveness. The process by which these sheets are fabricated, known as vacuum forming, is a scaled-down version of thermoforming, whereby according to the Wikipedia definition, “a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product.” The only difference with vacuum forming is that the heat-treated plastic is “stretched onto or into a single-surface mould.” A vacuum is then applied to the surface of the mould as well as the plastic sheet to fashion it into the desired shape.
In what applications can they be found?
No matter where you turn in a retail establishment these days, chances are you’ll find vacuum formable plastic sheets in use. That is because they are one of today’s packaging products of choice. Blister packets, clamshell packaging and plastic cup lids are just some of the everyday applications of the technology. However, such sheets are also used to make an eclectic array of other products that includes speaker casings and car dashboards. In addition, the acrylic used by the aerospace industry to make such components “as passenger cabin window canopies for military fixed wing aircraft and ‘bubbles’ for rotary wing aircraft” is oftentimes constructed of vacuum formable plastic sheets as well.
Heavy gauge vacuum formable plastic sheets can be found across a wide swath of industrial applications as well. For example, manufacturers of products and parts that are marketed and sold under the umbrella of another brand (original equipment manufacturers) use such sheeting in high volume. Sheets formed by way of vacuum are also a viable alternative for “complex fabricated sheet metal, fiberglass, or plastic injection molding.”
Thin vacuum formed plastic sheeting, on the other hand, is often found in “unit doses of pharmaceuticals” and is frequently used “for loose objects that are carded or presented as point-of-purchase items.”
Where might I encounter vacuum formable plastic sheeting?
If you have ever used an ATM machine to withdraw cash, if your doctor has ever ordered an MRI for you, if you have ever sat in the cab of a truck or in a railcar, if you have ever order a takeout cup of coffee, if you have ever bought an odd-shaped plastic-encased gadget or gizmo, chances are you have rubbed shoulders with some sort of PVC sheeting that has been formed by way of vacuum.
How does vacuum forming differ from other plastic production methods?
The process is beneficial for plastic parts that are either large or have many components. It is also a cost-effective way for businesses either whose tooling budget is tight or whose annual production volume is either moderate or small as a means to save some money. Finally, it is a sound choice for manufacturers who must develop their products rapidly.