What is Injection Molding? Its Working and Advantages

Injection Molding refers to the process of creating molded products. Synthetic resins are heated to a high temperature and then allowed to cool down to get any desired shape using a mold. This method is opted for producing parts in large volumes. A high-precision product not only requires selecting a good resin material. But also the proper physical parameters like speed and temperature of the melt injection.

Parts of Injection Molding Machine

Injection Molding Machine Construction
Injection Molding Machine Construction

Before understanding the technical know-how of induction molding, we must be familiar with the machine parts. An injection molding machine has two prime units: An injection unit and a clamping unit. Let us discuss each one of them in detail.

Injection Unit

1) Hopper
It is a container that stores the plastic material for the molding process.

2) Reciprocating Screw
It provides a forward motion to the plastic material present in the hopper.

3) Heater
The heaters surround the reciprocating screw and melt the plastic material.

4) Nozzle
The melted plastic material comes out from the injection unit via a nozzle.

Clamping Unit

1) Mold Cavity
The molten plastic falls into a hollow block of Steel or Aluminum which is known as mold.

2) Moveable Plate
Along with an ejector mechanism, this plate removes the molded product from the mold after the product cools down.


An Injection Molding Machine
An Injection Molding Machine
  • The process starts with pouring fine resin granules into the hopper. A heater then melts the granules, and the molten material moves forward with the reciprocating screw.
  • The injection unit then injects the melted material into the mold cavity by making use of a nozzle.
  • Inside the mold, the melted material flows through a tube known as Spruce. The Spruce connects to branched runners, which creates a uniform path to the molten material.
  • The branch runners finally connect to the mold cavity, where molten material gets collected.
  • When the material cools, the hardened material is removed from the cavity using an ejector plate.

The sequence of events discussed above makes up an Injection molding cycle. For mass production of products, this cycle repeats several times till the order gets completed.

After a brief introduction to injection molding, you may have got an idea of the complexity involved in this process. A service provider in this area must not only be experienced but reliable too. So, if you are searching for rapid prototyping services, visit PCBWay for high-quality products at economical prices.


High-scale volume production
The Injection molding process is ideal for high-scale production. It just requires programming the software once, and the machine prints thousands of prototyped parts with high accuracy.

Cost Savings
The rapid prototyping technology uses fully automatic advanced machines that require a maximum of one operator. It not only reduces the overall cost but also avoids human errors.

Higher Efficiency
With hot runner ejection mold systems, the time required to manufacture parts reduces in each cycle. Hence, a complete order completes within hours. It allows the machines to manufacture more molds in a given time, which improves the production rate.

Better Strength
The addition of fillers with base resins reduces the plastic density while molding and imparts strength to the molded part.

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