It then uses foam-fill simulation to allow the customer to spot potential problems with component design and manufacturing before the mould is made.
Because the issue of filling is considered in the design phase before moulds are built, instrument panels can be developed more quickly, their production process can be sped up and costs can be reduced compared to traditional techniques, the company added.
Instrument panels are safety-relevant, large and complex components that vehicle makers approve individually for every car model, BASF said
Foaming is crucial in their manufacture to ensure that the carrier, skin, PU foam and airbag combine properly, BASF said.
In addition to BASF’s technical support, with Ultrasim the PU foam can be manufactured efficiently according to process and part, the firm added.
Ultrasim contains tailor-made material models for PU systems so that the injection, foaming and hardening of the polyurethane can be precisely predicted.
The analysis accounts for the temperature-dependent reaction process and foam formation as well as the resulting density profile and flowability during foaming, BASF said.
This, the firm said, makes it possible to generate a location-independent calculation of the foaming process from injection via the complete mould filling to the final part density.
“Foam-backed parts can be tailor-made for vehicle interiors, optimised for cost and performance, BASF said. It is likely to extend the simulation software for integral and flexible foams with the medium-term goal to extend it to all moulded PU systems and gain insight into the ideal PU system for a given mould,” BASF concluded.
Get kitted up
Hennecke said that the process relies on an MT 18-2 deflection mixhead with mixture supplied through an HK 470/470 high-pressure metering unit. It delivers mixture at rates of up to 940 cm³/second. AutoRIM supplied the MG series mould carriers and the press is designed for moulds of up to 2T weight, Hennecke added.
Workers are protected by security systems with safety laser scanners and light curtains. Hennecke added that when opening, the upper and lower mould plates pivot towards the operator, making it easier for them to remove components.
The cycle time is around five minutes, Hennecke added: “The shot time is around 4 seconds with curing time around 120 seconds. The subsequent painting step takes around two minutes until curing is complete."
Meanwhile in Russia, KM has been working with the Nano Technology Centre of Composites (NCC) - the Russian lightweight construction research centre, based in Moscow - to produce a tailgate made of a self-supporting composite structure for electric buses.
"The customer's requirements were clearly defined: a substantial weight reduction;
Class A surface quality in a rigid, high-strength component.”
Wolfgang Hinz, product and sales manager at KraussMaffei
The tailgate uses a polyurethane matrix to support long fibre injection with in-mould coating, in a bus developed by NCC and Hungary’s Evopro Group.
The tailgate, which is 2.2 m wide x 1.4 m high, won a JEC Innovation Award this year.
"The customer's requirements were clearly defined: a substantial weight reduction; Class A surface quality in a rigid, high-strength component,” said Wolfgang Hinz, product and sales manager at KM.
He continued “A quick colour change and a wide range of colours were also requested. All of this had to be achieved in short cycle times.”
Part cost was also very important, he added.
KM and partners worked to develop the polyurethane-based long fibre injection process with in-mould coating. This gives parts with high-strength, and first-class surfaces from high gloss to matt in a wide range of colours, the company said.
Because self-releasing primers can be used, there is no need for external mould’s release agents, the firm added.
Technically too, the polyurethane composite approach stood out compared with traditional glass reinforced plastic systems. In the Daimler stone impact test, the LFI polyurethane system performed up to 600% better than comparable glass fibre reinforced plastic components painted with a primer.
KM said the system was delivered to NCC in 2015 and has been used in production successfully since.
The process revolves around a two-component paint spray machine and an LFI prototype mould.
In the first process step, the primer is painted into the mould and the polyurethane barrier coat is applied. Hinz said a KM RimStar compact spray mixing head is used to process the polyurethane components and ensure the material is produced a to consistent temperature, which, the firm said, “ensures good surface quality.”
Aston Martin and Dow in automotive collaboration
Aston Martin and Dow Automotive Systems have formed a technical partnership to improve the production and performance of high-end road and sports cars.
According to a Dow press release, the technical partnership will mean more Dow polyurethane products will be used in Aston Martin production models and racing cars.
"We look forward to working more closely with Dow Automotive Systems in a partnership that will enable us to accelerate development and demonstrate capabilities of new products and technologies in on-road and racing environments," said David King, vice president and chief special operations officer, Aston Martin Lagonda. "Our companies have had great success together for many years and this agreement moves us to the next level of collaboration through joint technology development."
Dow Automotive Systems said it has supplied Aston Martin with a range of customised Betamate and Betaforce structural adhesives. These have a range of processing windows and are designed for material combinations, including electro-coated steel, anodised aluminium, carbon- and glass-fibre reinforced composites.