Advantages and Disadvantages of Hot Runner Systems

Although hot runner system are the preferred choice of many manufacturing industries due to their precision and efficiency, they do carry some disadvantages as well. Considering both sides of the coin, this article will look at both that can help you make an informed decision when deciding which option is best for your business.

Advantages Of Hot Runner Systems

Hot runner systems are used in plastic injection molding to help the process of manufacturing. The main purpose of hot runners is to increase the efficiency of an injection molding . They do this by reducing the amount of time that it takes for the molding process, as well as increasing the quality of the product that’s being made.

There are many advantages that come with using hot runner systems in your plastic injection molding machine. They include:

Reduced cycle time

By injecting the material into the mold from multiple locations, you can reduce your cycle time significantly. This is because there are fewer steps involved in the injection process and less waiting time for cooling down between each cycle. This means that you can produce a greater number of parts in the same amount of time, which will save you money on labor and material costs.

Improved consistency

The most obvious benefit of hot runner systems is improved consistency. Hot runners offer a more consistent flow rate than cold runners, which means that the product can be poured into the cavity while it’s still hot or warm, meaning that the material will flow more consistently and quickly.

This improves quality and reduces waste. This is particularly important for high-demand products and those that require very specific specifications.

Reduced contamination risk

One of the biggest advantages of hot runner systems is that they reduce the risk of product contamination. When you’re producing a large quantity of parts, it’s easy to make mistakes when you’re working with molds that are intricate and complex.

The hot runner system allows you to eliminate these issues, because it minimizes the need for contact between the mold and the material being injected into it. This helps keep your products free from contaminants like dust and oil, which can damage their surfaces and make them difficult to clean.

Lower cost of ownership

Hot runner systems allow you to make more parts faster and with less downtime. This means that you can produce more in less time with fewer resources. The cost per part is also lower because you don’t need to pay for labor. The cost of labor is a major expense for many manufacturers. Hot runners are a great way to reduce this cost. They can also help you cut down on some other costs, such as materials .

Proper temperature control

Hot runner systems keep the temperature of the plastic at an optimal level so that it never cools too fast or too slow during injection molding cycles. If it cools too fast, it could result in defects like sink marks, pinholes and voids; if it cools too slowly, the cycle time will increase and you’ll have to pay more to keep the equipment running. Hot runner systems can also help you reduce scrap.

Consistent material flow through all pieces of plastic used in production cycles. Hot runner systems help ensure that each piece of plastic flows consistently through each cycle because they heat up at just the right time and stay at a set temperature.

Improved quality

Hot runners are designed to produce high quality parts every time which means less scrap and rework costs associated with producing poor quality parts. A hot runner system is the best way to ensure that your production runs are as efficient and cost-effective as possible. It can help reduce cycle time, eliminate scrap and rework costs, improve quality, and provide a more consistent material flow for each piece of plastic used in your production cycles.

disadvantages Of Hot Runner Systems

If you look for the advantages to hot runner systems, then probably you would have already thought of their ability to reduce labor costs and make the layout design smoother. But that’s not the entire picture. Hot runners have several other disadvantages, which you should be aware of before investing in it.

Increased Initial Cost

Hot runner systems are more expensive than other injection molding processes. This is because they require an additional piece of equipment, which can add up if you have multiple molds. In addition, this type of system requires more maintenance as well as training for operators who need to run it correctly each time they use it. This means that you will spend more money on labor-related expenses when you use this type of process compared to other methods like gravity or pressure injection molding processes.

Limited Runner Design

The runner system is designed for a specific part. If the part requires complex geometry, then the hot runner system must be modified by adding more parts or changing the existing ones. This increases cost, time and complexity of manufacturing.Another disadvantage is that hot runner systems are not very flexible. The design of the runners is often limited by the size of the part being molded. Also, if you need to change the part design at all, you may need to redesign your runners as well.

Increased Mold Assembly Time

One of the biggest challenges with hot runner systems is the assembly time. The process is much more involved than conventional molding and uses a higher number of components. This means that setup time is longer and it can be difficult to achieve repeatability from one part to the next.

High cost of maintenance and service

Hot runners need to be cleaned regularly to ensure that they are not clogged with plastic or other color contaminants. They also need regular maintenance to make sure that they are in good working condition. If a hot runner breaks down, it can affect the entire production line, since there is no way to change out just one tool without shutting down the entire system. If any part of your hot runner system stops working, it can cause a lot of problems for your business. You may have to shut down all or some operations until the problem is fixed, which will result in loss of revenue for your business.


If you’re still not sure which system is right for you, then the best thing to do would be to speak with your mold making provider or other professionals in this field and see what they have to say. I hope that you now feel a bit more comfortable when it comes to choosing between cold runner molds and hot runner molds.