What is Cold Runner Injection Molding?

Cold runner injection molding is a molding process where molten plastic is injected into a mold through unheated channels called runners. As the plastic flows through these runners into the mold cavities, both the part and the runners solidify and are ejected together, often requiring secondary processing to remove or recycle the excess material.

What Are The Benefits of Cold Runner Injection Molding?

What Are The Benefits of Cold Runner Injection Molding?

The use of cold runner molds is still common in the plastic industry despite some of the possible disadvantages mentioned below. This is most likely because of several practical and cost-effective benefits, such as:

  • Changing the color of plastic material is usually easier and more efficient with cold runner molds, as the system allows for quicker purging and less contamination between color batches.
  • Cold runner molds provide more cost savings not only in mold maintenance, which tends to be simpler and less expensive, but also in the overall mold production process due to their straightforward design and construction.
  • The designs of cold runner molds are less complicated, making them easier to build, modify, and fix when necessary.
  • It is relatively easier to operate with cold runner molds, especially for manufacturers who prefer a more traditional molding setup that does not require complex temperature control systems.

What Are The Cons of Cold Runner Injection Molding?

Cold runner molds usually use more material during production, though. This is because in every molding cycle, a plastic part and a runner are produced.

The runner is made of excess plastic material present in every shot. The excess material is removed and may be disposed of or reprocessed. Consequently, the processing time is usually longer. There are also side effects to using reprocessed plastic materials.

Professional Cold Runner Injection Molding Services by Richfields

Looking to use cold runner molds for your business? Partner with the experts at Richfields. Contact us today to develop a customized solution tailored to your products and production needs.

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