Blow molding is the art and science of making hollow plastics containers.  Different techniques such as extrusion, stretch blow, injection and co-extrusion are common. The PREP site features two high volume techniques; namely extrusion blow molding and injection stretch blow molding.  It also features different instructional media such as video clips, animations and interactive stills all focusing toward virtual laboratory experiences.

While there is no substitute for hands-on experiences, the virtual lab process will give some “feel” for each process

(without the need for ear plugs!).   Extrusion blow molding will feature machine component identification, parison control and HDPE-type bottle making.  Injection stretch blow molding will feature machine component identification, preform control, plastic orientation and PET-E bottle making. Enjoy your learning experiences.

For more information about tools for teaching blow molding, contact Dr. Stan Baczek, associate professor of Plastics and Polymer Technology at Penn College.

animations

A warm, injection molded preform (plastic test tube with the precisely molded cap threads) is conveyed to the blowing station. The “stretch rod” orients the plastic along its length. Next, low-pressure air begins the blowing process followed by a high-pressure burst. The cold mold walls solidify the molecular biaxial orientation into the container, open and, finally, eject the product from the mold.

Why are there puffs of air shown in the animation?

Think about it!