Injection compression molding

The injection compression molding process enables the production of low-stress, thick-walled components without sink marks and with high contour accuracy. However, this is a complex process and requires a detailed knowledge of the process and high-quality machine technology. That’s where we come in.


Injection molding machines with high positioning accuracy and high reproducibility, such as our hydraulic and electric ALLROUNDERs, are in demand for injection compression molding. However, you can also rely on us when selecting compression technology and for the design and layout of the mold.


  • Universal injection compression moulding: machine controller enables free, customized programming without the need for non-standard programs
  • Hydraulic ALLROUNDER S: ideal for long compression paths and high compression forces
  • Electric ALLDRIVE series: for positioning accuracy to within one thousandth of a millimeter

Process technology

Injection compression molding
This process is characterized by a change in cavity volume during the ongoing injection and/or holding pressure phase. For this reason, the mold must be designed so that the cavity is sealed, even in the partially open state. With our expertise, this is sure to succeed.
to application consulting

Application examples

LED lens
ARBURG participates in the OptiLight research project for the energy-efficient production of innovative hybrid lenses for LED streetlights. With the injection compression molding process, precision free-form surfaces are produced which deflect the light in a targeted manner, according to a rectangular illumination profile.
to the molded part

Belt pulley
In the case of thermosets, injection compression molding increases part strength and prevents sink marks. The belt pulley is produced on a hydraulic ALLROUNDER 470 S using main axis compression molding with the dual-pump technology. The compression gap in the mold is 7 mm.

Spectacle lenses
In the case of so-called ophthalmic lenses for spectacles, the thickness of the component can be determined via the compression path. The compression time for a 10 mm lens is 90 s. A hydraulic injection molding machine with multi-pump technology is used.