Industry

01 CHALLENGE

To develop its product, our customer needed a partner capable of overmoulding a bearing while respecting the characteristics of the product. The dimensions had to be perfect in order to ensure the proper use of the part and guarantee its life span.

The alignment between the bearing in the pump cover and the pump shaft was of major importance, as a shift could lead to an inaccurate flow rate. The injection moulding technology provided to our customer therefore had to take into account the specificities of the insert.

02 APPROACH & SOLUTION

Our design department first carried out a rheological study in order to identify the risks linked to the injection moulding process, which could compromise the quality of the bearing, and to guarantee the complete filling of the part. The flow front temperature, the melted mass and the pressure exerted on the bearing were therefore analysed.

Thereafter, the double cavity tooling was designed by a moulding partner in order to optimise the injection moulding process. The injection moulding temperature and the pressure exerted by the material on the insert created a constraint that had to be mechanically balanced. During the dimensional development phase, a pre-deformed model was made in the tooling to ensure the dimensional requirements specified by the customer were met.

The correct positioning of the insert before overmoulding also had to be ensured. Our engineers therefore developed a process for automatically placing the bearing in the tooling. The surface finish of the insert was also taken into account to limit its impact and control the repeatability of the overmoulding process. Indeed, the adhesion between the bearing and the overmoulded material had to be guaranteed to ensure the function of the overmoulded assembly.

• Rheological study 
• Optimised tooling and injection moulding technology
• Process for automatic distribution of inserts
• 50 t injection moulding machine 
• 2 product versions