skip to Main Content
Speak with a Training Specialist 1-800-826-1901 Interested in Seminar Training? Click Here Request Info Tech Support

Webinar: Step Two of the Molding Cycle, Making Plastic Flow

Plastic flow rate is one of the four basic plastic variables. Establishing accurate control is vital to a repeatable molding process.

In this webinar, our expert instructor examines the topic of plastic flow rate. The unique properties of polymer molecules make accurate control of flow rate vital to a repeatable molding cycle. All polymers exhibit some level of non-newtonian flow behavior. That means their viscosity decreases as flow rate increases. Newtonian materials, like water, maintain a consistent viscosity as flow rate increases.

The reason plastics’ viscosity decreases with increased flow rates is because of their molecular structure. Plastic molecules are extremely long for their width; thousands of times longer than they are wide. And at rest in a liquid state they are resistant to flow. As plastic molecules are forced to flow, during mold filling for example, these long molecules orient, or line up, in the direction of flow, greatly reducing their viscosity. In fact, this property makes molding plastics possible at the pressures and temperatures in use today.

So while molecular orientation makes filling and packing the mold easier, it also has significant effects on molded part properties. Some of these properties are desirable and some are not. There are specific techniques for controlling the amount of orientation developed during fill/pack as well as the amount retained in the molded part. In this webinar you’ll gain a decent understanding of plastic flow rate.

Topics covered include:

  • How to take advantage of non-newtonian behavior to reduce fill times
  • How to maintain consistent fill times despite changes in the pressure and temperature of the melt
  • What to expect for part properties as fill rate is increased or reduced
  • Best practices for retaining or reducing areas of molecular orientation in the finished part

Take part in this FREE webinar to learn and apply molding techniques that will dramatically change the way you process.


Special Guest: Donald C. Paulson

2021 Plastics Hall of Fame Inductee(read more here), Donald Paulson is the founder and chairman of Paulson Training Programs, Inc. and the creator of the now widely accepted method of teaching plastic processing from the “Plastics Point of View”. Don will join this webinar and give his personal account of his years of research with the General Motors Institute that lead to transforming injection molding from an art to a science. An experience you won’t want to miss.

Visit our webinar page to register for this webinar and upcoming topics. Also, gain access to previously recorded webinars. There’s a wealth of knowledge from Paulson all at your fingertips!

This Post Has 0 Comments

Leave a Reply

Your email address will not be published. Required fields are marked *

I want to try it FREE