There are many methods used to make PET plastic bottles […]
There are many methods used to make PET plastic bottles, but the most common method can be broken down into the following steps:
Step 1: First heat the PET to melt it into a molten state, and then put it into a tubular mold. This process is called injection molding. Once the PET becomes the same shape as the mold, it is called a parison. After the system has cooled, the parison is cut to the correct length.
Step 2: The parison is then reheated and placed in a mold shaped like the bottle being manufactured. Then, a steel rod is placed inside the parison itself, and high-pressure air is blown to stretch the parison into the shape of the mold surrounding it. The molecules inside the PET are then polarized, and the stretching process leaves you with a plastic bottle.
Step 3: Then the bottle must be quickly cooled and removed from the mold. Manufacturers often use several different methods to quickly cool bottles. Some of these methods are direct and others are indirect. For example, water can be pumped through pipes surrounding the mold to indirectly cool plastic bottles. Alternatively, the plastic can be cooled by directly applying carbon dioxide.
Step 4: Then reduce most of the bottles produced by the manufacturer to a certain size. If the bottle is made in a continuous molding process, you need to trim a bottle from the bottle next to it. If the bottle is made in a discontinuous molding process, some excess plastic may infiltrate. This will require pruning.
Step 5: Now the bottle can be delivered to the destination.