Plastic Injection: From Granule to Finished Part

Plastic injection (or injection molding) is the standard industrial process for manufacturing polymer parts, from simple protective shells to high-safety automotive components.

Unlike 3D printing, which builds material layer by layer, injection molding allows for the production of thousands of strictly identical parts in a few seconds.

The 4-Step Cycle

1. Melting (Plasticizing)
The raw material, in granule form (ABS, PP, PA6...), is poured into the hopper. It is heated and mixed by a screw until a homogeneous molten paste is obtained at 200°C-300°C.
2. Injection
Under colossal pressure (several hundred bars), the material is injected into a closed steel mold. It fills the cavity in a fraction of a second.
3. Cooling
The mold is temperature-regulated by water circuits. The material solidifies and regains its rigid shape. This is the longest stage of the cycle.
4. Ejection
The mold opens, and ejectors push the part out of the cavity. The robot grabs the part, and the cycle begins again.

Why choose this process?

Repeatability & Precision

Once the mold is set, part #1 and part #100,000 are identical to the micron. It is the only viable technology for complex assembly (clipping, screwing).

The Central Role of the Mold

The key to injection is tooling. A mold is an investment (CAPEX), but it determines the part price (OPEX).
Our approach: At Moulding Injection, we reduce this entry ticket thanks to our hybrid strategy (Mold made in China, Secure production in Belgium) or via "prototype" aluminum molds for your small series.

Misconception: "It's only for millions of parts"

False. Today, we make injection profitable starting from 500 or 1,000 parts thanks to simplified tooling. Don't get stuck in 3D printing; switch to "real material."

Validate your project feasibility

Shared Risk: We Finance 50% of Your Mold

bio-plastic, PLA