Mini Countryman’s lightweight instrument panel wins SPE innovation award

A lightweight instrument panel produced for BMW Group’s Mini Countryman vehicles has won top honours at the Automotive Innovation Awards organised by the Society of Plastics Engineers (SPE).

The part won the Body Interior category at the annual awards for both the innovative production process combined with lightweight-enabling materials from SABIC, which help reduce the part’s weight by about 15 percent versus a comparable solid plastic component.

The injection moulded panel uses a high flow concentrate long glass fiber-reinforced polypropylene (LGFPP) material (known as STAMAX resin) from SABIC and a dedicated

masterbatch solution in a structural foaming process with core-back technology.

Using this approach, the material injects into and completely fills the mould. The mould then opens to allow for foaming on the core side of the mould. This foaming part of the core-back technique increases the wall thickness of the part from 1.9 mm to 4 mm. This delivers the required strength and rigidity characteristics without adding weight. This foamed solution with the STAMAX resin also typically requires less material during processing and enables shorter cycle times.

“Congratulations to BMW Group and all those involved in this collaborative effort,” said Scott Fallon, SABIC’s Global Automotive Business Leader. “This award is well deserved in that success with this foaming technique does not come easily. Designing the tool and optimising the process for the best results requires skill, knowledge and persistence from all parties. We take pride in our ability to step in and provide the support required to help develop and validate this lightweight solution.”

SABIC performed extensive CAE warpage analysis to predict warpage behaviour of the part. It says this evaluation, early in the development process, provided valuable insights for the design of both the part and the mould, which enabled building the mould correctly the first time.

“This sort of computer simulation is standard practice when it comes to solid plastic parts, but the industry is still in the early stages of developing simulation tools for foamed plastic parts,” explained Fallon. “As evidenced through this programme, we have predictive capability that we can apply today. We continue to work on new material formulations and improved ways to predict the properties of foamed parts.”