Haitian has been innovating injection molding processes to meet the increasing demand for lightweighting in the automotive industry. The manufacturer’s expanded injection PP solution (EIPP) is widely used in the production of automotive interior parts such as door panels.

Foaming technology

Foaming technology (physical foaming and chemical foaming) is a high-precision injection molding technology for reducing the weight of products. It significantly improves part deformation and dimensional stability while reducing clamping force.

Expanded injection PP solution (EIPP) is a chemical foaming process.

EIPP is a chemical foaming process in which the surface is foamed after injection and has a low contact temperature with the mold. In contrast, the center has a high temperature, resulting in foam release in the direction of mold cavity expansion, with dimensions controlled to +/- 0.03 mm accuracy based on precise foam expansion control.

Precision control technology

The controller plans the movement curve based on the required process positioning and speed, and it reads real-time position data from digital transducers on the tie bar (or mold) and pressure sensor data from the hydraulic system. Next, it quickly calculates the deviation between the actual and theoretical spatial position of the tie bar (or mold).

Closed-loop control system.

The controller dynamically adjusts the hydraulic power system and the high-frequency response servo valve system based on the deviation to achieve stability of the mechanism’s spatial state and high-precision positioning of the platen (or mold).

Advantages of EIPP

EIPP has the advantages as follows: 

• Quality improvement: higher dimensional stability and improved molding of the housing.

• Cost reduction: shorter cycles, material savings, optimized part design, longer mold life and reduced machine tonnage.

• Time saving: faster mold validation, optimization of part and mold design.