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What is Blow Molding?

If you have ever wondered how bottles are made, look no further than Streamline Plastics Utah blow molding. Blow molding is a molding process that uses hot plastic, exterior molds and air to inflate heated polymers. Although elementary blow molds can be made in an amateur shop, more sophisticated machinery is required for products that will be sold in the marketplace.

Different Methods for Blow Molding Plastics

There are three main methods for blow molding plastic in a manufactory setting:

  1. Extrusion blow molding. This method involves injecting melted plastic into a hollow tube, which is then enclosed in a cold metal mold. Air is blown into the middle of the hollow tube, shaping the bottle or container. Then the hollow tube is discarded after the bottle has been removed from the mold.
  2. Injection blow molding. This process is more practical for a lower level of production, making it useful for small medical or single-serve bottles. There are three steps to this blow molding method, which are injection, blowing and ejection. The first step occurs when the melted polymer is injected into a hollow preform mold that has been heated. The core rod (at the center of the hollow mold) is inserted into the blow mold where the second step takes place. After the plastic is blown into shape, the mold is removed and the container is taken off of the core rod.
  3. Stretch blow molding. This method involves molding the plastic into a preform via the injection molding process. The preform is heated so that the plastic can stretch out. Afterwards it is placed inside a hollow mold and blow molded until they are the correct shape.

Most finished products have leftover bits of plastic attached, which requires spin trimming to make sure that the product is in working order.

Custom Blow Molding

Streamline Plastics is an injection molding company that creates turn-key plastic products for the marketplace. Streamline’s blow molding department has a variety of different molds to choose from, including:

  • F-style containers
  • Wide mouth jars
  • Boston round mouth jars
  • Decanter/Carafe

Clients can also create their own custom designs for bottles or jars that they wish to have blow molded. This is an excellent option for special products or solutions.

Streamline Plastics: Producing Blow Molding Products

Streamline Plastics has low prices for high quality blow molding services, including plastic blow molding, and injection blow molding. Streamline has a high number of options available for blow molding, making us a flexible manufacturer for your marketplace needs. Contact us today by calling 801-782-3660.


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