Runner is the basic form of injection molding! The so-called cold runner is a conventional injection mold, and after injection molding, there is condensate in the runner that needs to be removed!
With the reduction of resources and market competition, the prices of raw materials have significantly increased, which makes it very necessary to make a big fuss about saving materials! This is also an important reason for the generation of hot runner! It can be said that it is an inevitable product of the development of social industrialization.
The emergence of hot runners has solved the problem of resource waste and cost savings, and has also achieved significant results in injection molding processing. The hot runner has gradually developed into the main direction of injection mold development and will definitely be popularized! Due to cost accounting issues, many small and medium-sized molds have not yet applied hot runners! There is still a small portion of the material that must be (better controlled) injected into cold runner molds!
So now in the injection mold industry, there is a distinction between a cold runner and a hot runner!

Extended Information:

Advantages of hot runner molds

1. Shorten the cycle

The molding cycle of the workpiece is shortened, and due to the lack of cooling time limitations in the runner system, the workpiece can be ejected in a timely manner after solidification. Many usesHot runnerThe forming cycle of thin-walled parts produced by molds can be less than 5 seconds,

2. Saving plastic

In pure hot runner molds, there is no production cost due to the absence of a cold runner. Hot runner technology is an effective way to reduce material costs and reduce material costs.

3. Reduce waste

Reduce waste and improve product quality. During the hot runner mold forming process, the temperature of the plastic melt is accurately controlled in the runner system. Plastic can flow into each mold cavity in a more uniform and consistent state, resulting in parts of consistent quality. The parts formed by hot runner have good gate quality, low residual stress after demolding, and small deformation of the parts.

4. Production automation

Eliminating subsequent processes is beneficial for production automation. The finished product is formed by a hot runner mold, without the need for trimming gates or recycling cold runners. Beneficial for production automation.

Cold runner, compared to hot runner, produces cold materials that need to be crushed and recycled again, but the mold design is simple and widely used.