DSM has developed new high temperature resistant grade of its Arnitel® thermoplastic copolyester elastomer (TPC) for production of flexible hot charge air ducts used in turbocharged engines.
DSM’s New TPC Replaces Plastics-rubber and Metal-rubber Combinations
|Fig. 1: Hot Charge Air Ducts
Arnitel HT will allow system suppliers to produce the ducts in a single material and using a single process step. The current standard practice is to assemble separate elements in hard thermoplastics or metal and soft thermosetting rubbers, which need to be produced in diverse operations. Switching to Arnitel HT
will provide producers with a significant improvement in process efficiency, cost reductions of up to 50% and weight reduction of up to 40%.
Hot Charge Air Ducts for Engines
Hot charge air ducts
are common features in advanced petrol and diesel engines.
- Ducts transfer hot compressed air from the turbocharger or the supercharger to the intercooler in a system that increases the efficiency of the engine by using higher operating pressures.
- Ducts need to withstand very high temperatures for long periods.
- Flexibility is important criteria for ducts because they need to be easy to install to handle movements of the engine relative to the cooler (which is fixed on the chassis of the car).
These needs are normally met by using ducts with a central section in a rigid high temperature thermoplastic such as DSM’s Stanyl® or Akulon® polyamide, and end sections in a thermosetting polyacrylate, ethylene acrylic or fluoro rubber with a woven reinforcement.
Disadvantages of Traditional Hot Charge Air Ducts
There are several disadvantages associated with traditional hot charge air ducts. Few of them are listed below:
- Assemblies based on thermoset rubbers are heavy
- Relatively low mechanical performance dictates the need for thick walls to be able to handle the demands of the hot charge air duct.
- Total system costs of rubber-plastics (or metal)-rubber solutions are high.
- The production process is a multi-step one: molding of the various elements, followed by assembly; this adds costs and takes extra time, and it also introduces extra opportunities for defects to be introduced, both during production and in use.
- Companies producing the ducts may even buy some sections rather than make them themselves because rubber processing and plastics processing require different skills.
- To reduce the risk of failure due to creep at the joints reinforcement rings is placed inside the tubes.
- Process in not eco-friendly as rubber is not easy to recycle.
- Energy consumption during processing as well as the working environment for operators is not too sustainable.
Advantages of DSM’s Arnitel HT TPC-based Hot Charge Air Ducts
Arnitel HT eliminates all major disadvantages.
- It outperforms other thermoplastic elastomers with its ability to withstand continuous operating temperatures of up to 180°C and peaks of up to 190°C.
- It offers good resistance to the sorts of oils and chemicals found in automobile engine environments.
- It can be used to produce the entire duct in a single piece using 3D suction blow molding because of Arnitel HT’s combination of elasticity with high mechanical strength.
Fig. 2: 87% of All New Cars Contain DSM Materialsn
“Ducts produced in Arnitel HT can withstand the internal operating pressures which are demanded by car producers, not only for models in production today but also for upcoming generations,” says Kurt Maschke, Global Segment Manager Air/Fuel at DSM. “And by using a single solution based on a material with excellent mechanical performance and a relatively low density in an optimized design, it is possible to obtain weight savings of as much as 40%.”
DSM has been able to build on previous successes in improving the long-term thermal stability of Arnitel. Other grades have already proven themselves in existing duct applications requiring good heat resistance
One of the first producers of hot charge air ducts to take advantage of this new innovation is CIKAUTXO, headquartered in Spain, which has capability in production of rubber components and also in plastics blow molding and injection molding. The company worked together with DSM on the development of the first part in Arnitel HT, and exchanged valuable information for improvements in the material, processing, and part validation.
“We believe that Arnitel HT will enable us to make important cost reductions and increase consistency and reliability in our production of high performance ducts,” says Dr. Gurmendi at CIKAUTXO. “Our new ability to make better optimized parts in a single step provides us with a tangible advantage in the market.”
Meet the Extreme with DSM
DSM offers high-performing plastic solutions, technologies and expertise for the extreme demands of next-generation vehicles. These materials are a driving force in light weighting, downsizing and e-mobility. On the road to zero emissions it’s time to think differently. To think beyond metal.
About DSM – Bright Science. Brighter Living.™
Royal DSM is a global science-based company active in health, nutrition and materials. By connecting its unique competences in life sciences and materials sciences DSM is driving economic prosperity, environmental progress and social advances to create sustainable value for all stakeholders simultaneously. DSM delivers innovative solutions that nourish, protect and improve performance in global markets such as food and dietary supplements, personal care, feed, medical devices, automotive, paints, electrical and electronics, life protection, alternative energy and bio-based materials. DSM and its associated companies deliver annual net sales of about €10 billion with approximately 25,000 employees. The company is listed on Euronext Amsterdam.