Extrusion is a common manufacturing method used to produce plastic tubing. The extrusion process utilizes a hopper to push melted plastic materials through a die in order to create a unique tube-shaped design.

If you are in the market for custom plastic tubing, you will probably come across some extrusion terms you may not be familiar with. An understanding of these terms is essential if you want to end up with the plastic tubing that will meet the specific needs of your project.

1. Camber and Bow

Two terms that you will need to be familiar with as you discuss custom plastic tubing are camber and bow. Each of these terms refers to a lack of straightness in finished plastic tubing.

Once melted plastic is extruded through a die, the cooling process begins. Even, consistent cooling is needed to retain the shape of plastic tubing as it moves down the conveyor line.

Any tubing that exhibits side-to-side warping is said to have a bow. Tubing with up-and-down warping has a camber. You want to avoid bow and camber in order to preserve the integrity of the finished tubing once it is put to use.

2. Starve Feeding

You may hear plastic tubing manufacturers talk about starve feeding. This is a term that refers to the way plastic materials are fed into the extruder.

Flood feeding occurs when technicians rely on the hopper itself to feed the extruder via gravity. Starve feeding is a process whereby technicians meter the amount of plastic materials moving through the extruder at any given time.

Starve feeding can slow production times but offers technicians greater control over the extrusion process. The plastic tubing generated via starve feeding tends to have fewer flaws and adheres more closely to specifications than tubing generated through flood feeding.

3. Die Swell

Designing the die that will be utilized during extrusion is critical to the overall quality of plastic tubing. Die swell is a term that you will hear often when talking about the design of an extrusion die.

Once melted plastic is extruded through a die, it has a tendency to relax. This relaxation results in slight swelling referred to as die swell.

It's important to take die swell into consideration when designing a die so that the finished plastic tubing created through extrusion meets your desired specifications.

Being able to converse with a plastics manufacturer using industry terms will help you improve the quality of your custom plastic tubing over time.