Bottle Processing Equipment
There are two basic molding methods for PET bottles, one-step and two-step. In two-step molding, two separate machines are used. The first machine injection molds the preform, which resembles a test tube, with the bottle-cap threads already molded into place. The body of the tube is significantly thicker, as it will be inflated into its final shape in the second step using stretch blow molding.
In the second step, the preforms are heated rapidly and then inflated against a two-part mold to form them into the final shape of the bottle. Preforms (uninflated bottles) are now also used as containers for candy, and by some Red Cross chapters to distribute to homeowners to store medical history for emergency responders.
In one-step machines, the entire process from raw material to finished container is conducted within one machine, making it especially suitable for molding non-standard shapes (custom molding), including jars, flat oval, flask shapes etc. Its greatest merit is the reduction in space, product handling and energy, and far higher visual quality than can be achieved by the two-step system.
Read more about this topic: Polyethylene Terephthalate
Famous quotes containing the words bottle and/or equipment:
“Let us not succumb to nature. We will marshall the clouds and restrain tempests; we will bottle up pestilent exhalations; we will probe for earthquakes, grub them up, and give vent to the dangerous gas; we will disembowel the volcano, and extract its poison, take its seed out. We will wash water, and warm fire, and cool ice, and underprop the earth. We will teach birds to fly, and fishes to swim, and ruminants to chew the cud. It is time we looked into these things.”
—Henry David Thoreau (1817–1862)
“Biological possibility and desire are not the same as biological need. Women have childbearing equipment. For them to choose not to use the equipment is no more blocking what is instinctive than it is for a man who, muscles or no, chooses not to be a weightlifter.”
—Betty Rollin (b. 1936)