Manufacturers today use hot runner system technique to fill the cavities in the mold parts. The temperatures of the runner and gate are controlled so that the material is heated to its flow temperature, while the mold keeps cooling down. The hot runner system technique enables the molding of high-quality plastic products with shorter cycle times and lower production costs.
Figure 1: Hot runner system
It is widely used in the plastics industry, and popularity is growing in other industries as well. This technique has many advantages over traditional injection molding techniques. We will discuss in this blog the importance and usage of hot drop injection molding.
Hot runner system – Introduction
It is an important injection molding method that enables the production of high-quality plastic products with shorter cycle times and lower production costs. This system allows the assembly of heated components used to inject molten plastic into molds. These systems are classified according to their method of heating that is internal or external.
This system is often used in injection molding, overmolding, and plastic extrusion applications. The main advantages are:
- Reduced cycle times
- Reduced molding costs
- Increased production efficiencies
- Increased product quality
Difference between hot and cold runner system
Figure 2: Hot runner vs. cold runner system
It is very crucial to know the difference between the hot and cold runner systems because many users get confused at once.
- The main difference between the hot and cold runner injection molding systems is that in a hot runner system, the runner is heated whereas in a cold runner system, the runner is not heated.
- Secondly, the gate in a hot runner system is also heated so that the plastic can flow easily into the mold cavity, whereas in a cold runner system, the gate is not heated.
- Thirdly, it is more expensive than a cold runner system.
- Finally, it produces less waste because the plastic does not solidify in the runner, whereas the cold runner system produces more waste because the plastic solidifies in the runner.
Hot runner injection molding process
Every injection molding industrialist must know the process of hot drop injection molding to avoid defects in the mold parts. If the process is carried out correctly, it can result in the production of high-quality molded parts. The hot runner injection molding process is as follows:
- First, the material is placed into the hopper of the injection molding machine.
- Then, the material is heated to its flow temperature in the barrel of the machine.
- After that, the material is injected into the mold cavity at a high pressure. Here, the hot runner system is used to let the material flow into every corner of the cavities.
- Finally, the mold is opened and the molded parts are ejected.
It is very beneficial in mass production because it reduces the cycle time and production cost. Moreover, it increases the productivity and quality of the product.
Hot runner system types
With the passage of time, manufacturers have discovered many types of the hot runner system. The most common types of hot runner system are as follows:
Manifold type hot runner system
It is the most commonly used system. In this system, the molten plastic is injected into the mold cavity through the manifold. The hot runner manifold is connected to the nozzles which are placed in the mold cavity. The advantage of this system is that it is very simple to use and maintain.
Shuttle type hot runner system
It is mostly used for large molded parts. In this system, the molten plastic is injected into the mold cavity through the shuttle. The shuttle is connected to the nozzles which are placed in the mold cavity. The advantage of this system is that it can be used for large molded parts.
Valve gate hot runner system
This type of hot runner system is mostly used for small molded parts. In this system, the molten plastic is injected into the mold cavity through the valve gate. The valve gate is connected to the nozzles which are placed in the mold cavity. The advantage of this system is that it can be used for small molded parts.
Price of hot runner system
The price depends on many factors such as the type of system, the number of nozzles, the size of the system, etc. However, in general, the price of a hot runner system ranges between thousands..
If you are looking for a hot runner system for your business, please contact us and we will give you the best price.
Business compatibility with hot runner injection molding
Now the question arises if your business is compatible with hot runner injection molding, which means that whether your business gains profit by using this procedure or not. So, following are the circumstances where hot runner injection molding is advantageous:
- If you manufacture products which require many colors
- If you want to save money on the mold
- If you want to reduce the cycle time
- If your molded parts are large
- If you want to produce high-quality molded parts
- If you want to increase the productivity of your business
- If you want to reduce the production cost
These were the circumstances under which hot runner injection molding is advantageous. So, if your business meets any of these conditions, you should use this procedure.
Molding services at Go4 Mould
Go4 Mould is well known for its molding services in almost 40 countries. We use high-quality raw material for making our mold parts. Our injection molding gallery is filled with numerous molds successfully running across the world including pipe fitting mould, crate mould, basket mould and many others. Our clients are satisfied and leave good feedback hence increasing our monthly selling score.
Why do we use the hot runner system?
We use this system because it is cost-effective and enhances the productivity of your project. You can use it for making small molded parts, large molded parts and mass production.
Where to buy a hot runner system?
In China, there are plenty of options from where you can buy it. Search the prices online and then you can compare them with the manufacturer’s displayed prices. If you feel satisfied, you can go ahead for making the contract. Go4 also provides assistance in finding a manufacturer through our business consultants.