• 2023-10-09
• 681
• 5 Comments

What type of injection mold should use hot runner system?

The cold runner refers to the part between the mold entrance and the product gate. Plastic in the flow channel by injection pressure and its own heat to maintain the flow state, the flow channel as a part of the molding material, but does not belong to the product. Therefore, when we design the mold, we should consider both the filling effect and how to save materials by shortening and reducing the flow path, ideally, but in practical applications, it is difficult to achieve the best of both worlds.

Hot runner, also known as no runner, means that the plastic in the runner does not solidify after each injection, and the plastic product does not have to be removed from the water outlet in the runner when it is demoulded. Because the plastic in the flow path is not solidified, the flow path remains open at the time of the next injection.

In short, the hot runner is an extension of the injection molding machine nozzle.

Hot runner mold has been widely used in various industrial developed countries and regions in the world. This is mainly because the hot runner mold has the following significant characteristics:

Save plastic raw materials

In the pure hot runner mold, there is no cold runner, so there is no production cost. This is particularly significant for applications where plastic is expensive. In fact, the major international hot runner manufacturers have developed rapidly in the era of expensive oil and plastic raw materials in the world. Because hot runner technology is an effective way to reduce the cost of materials.

Eliminating subsequent processes is conducive to production automation.

The product is finished after the hot runner mold is formed, and there is no need to trim the gate and recycle the cold runner. Conducive to production automation. Many foreign product manufacturers combine hot runner with automation to greatly improve production efficiency.

Rising mold cost

The price of hot runner components is relatively expensive, and the cost of hot runner mold may be greatly increased. If the parts production is small, the mold tool cost ratio is high, and the economy does not spend. For mold users in many developing countries, the high price of hot runner system is one of the main problems affecting the wide use of hot runner mold.

Complex operation and maintenance

Compared with the cold runner mold, the operation and maintenance of the hot runner mold are complicated. If the use of improper operation is easy to damage the hot runner parts, so that production can not be carried out, resulting in huge economic losses. For new users of hot runner molds, it takes a long time to accumulate experience