Hot runner for medical plastic injection molds Pros and cons, and how do we use them?
2022/6/1 521

Plastic components are used in a variety of industries, and manufacturing these components by injection molding has come a long way. Generally speaking, there is a choice between traditional cold runners or more advanced hot runners. Each option has its own unique advantages and disadvantages, so understanding these differences and how they relate to your application can have a major impact on your productivity and overall profitability.


1. Advantages of Medical plastic injection mold hot runner:

(1) Improve product quality

During the Medical plastic injection mold hot runnerforming process, the plastic melt temperature is accurately controlled in the runner system. The plastic can flow into each mold cavity in a more uniform state, the gate quality of the parts formed by the hot runner is good, the residual stress after demolding is low, and the deformation of the parts is small.

Medical plastic injection mold hot runner 2.jpg

(2) Conducive to production automation

The finished product is the finished product after being formed by the hot runner mold, and there is no need to trim the gate and recycle and process the cold runner. Conducive to production automation.


Second, the disadvantages of Medical plastic injection mold hot runner:


Although hot runner molds have many significant advantages compared to cold runner molds, mold users also need to understand the shortcomings of hot runner molds, which can be summarized as follows:


(1) Rising mold costs

Hot runner components are more expensive, and the cost of hot runner molds may increase significantly. If the output of parts is small, the proportion of mold tool cost is high, which is not economical.


(2) High requirements for hot runner mold manufacturing process equipment

Hot runner molds require precision machining machinery for assurance. The integration and cooperation requirements of the hot runner system and the mold are extremely strict, otherwise there will be many serious problems in the production process of the mold.

Medical plastic injection mold hot runner.jpg

(3)complex operation and maintenance

Compared with cold runner molds, hot runner molds are more complicated to operate and maintain. Improper use and operation can easily damage hot runner parts, making production impossible. cause huge economic losses. For new users of hot runner molds, it takes a long time to accumulate experience


3. When we use Medical plastic injection mold hot runner?

The hot runner is the most complex and expensive part used on the mold, so special care should be taken in its design. The junction box should be designed above the mold, and the specific design and use should strictly follow the supplier's technical manual. Due to the long order cycle of the hot runner, in the early stage of mold design, its specifications should be determined as soon as possible to ensure sufficient time to purchase.

The injection nozzle that is connected to the cavity on the hot runner should be lined and cooled when the mold structure allows it, especially when the fixed mold has parted.

The choice of the hot runner model should be determined according to the requirements of the product. The form and size of the nozzle head should be determined according to the product plastic material and product size. When NOZZLE is directly on the product, the type with valve pin can be selected to ensure that the gate will not be too high to affect the appearance and use of the product.


Our cold runner and hot runner mold projects can be provided. As a Medical plastic injection mold manufacturer, only to meet your needs, maximize your cost and achieve sustainable development