A lightweight airtight air duct that can be applied directly to commercial vehicles has been developed. It is expected to be of great help in securing domestic production technology to replace existing French air ducts and increasing the self-sufficiency of the domestic automobile industry.

The research team of Senior Researcher Bae Seung-hoon of the Busan Machinery Technology Research Center of the Korea Institute of Machinery and Materials (President Ryu Seok-hyun) under the Ministry of Science and ICT, Eugene SMRC AT (CEO Kim Heung-sik), and SH Korea (CEO Woo Sang-il) have made a groundbreaking improvement in the air duct manufacturing technology for automobile cockpit modules. They are on the verge of commercialization as they satisfied the complete vehicle standards in performance evaluations.

Existing air ducts were made of high-density polyethylene (HDPE), which made them heavy and had poor insulation performance, leading to significant heat loss. They were also inconvenient to assemble and had other problems such as noise generation. This resulted in reduced vehicle fuel efficiency and uncomfortable ride, and there was also a safety issue as the duct could break in the event of an accident and injure the driver.

The air duct developed by the joint research team this time is characterized by a weight reduction of approximately 60% compared to existing products through the use of foam sheets, and significant improvements in airtightness, noise reduction performance, and safety.

The new air duct was manufactured through vacuum forming and hot knife processes using foam sheets. This process significantly increases productivity by lowering the defect rate and enabling the precise implementation of complex shapes compared to conventional blow molding. In addition, the use of polyethylene (PE) foam material improved insulation performance and maximized noise reduction, thereby simultaneously improving the vehicle’s fuel efficiency and comfort.

The research team preheated the PE foam sheet and formed the shape by suction on the upper and lower vacuum molds, and at the same time, joined the upper and lower foam sheets by compression to form the shape. This was followed by a post-processing step where the edges were precisely cut using a hot knife process.

The joint research team then conducted a performance evaluation to ensure the reliability of the developed air duct and confirmed that it met the standards for finished vehicles. In the process, they also secured technology to extract dynamic properties of polymer structures such as PE or polypropylene (PP).

“This product appears to solve the shortcomings of existing air ducts,” said Bae Seung-hoon, a senior researcher at the Korea Institute of Machinery and Materials, who led the study. “It will likely be applicable to a variety of vehicle models in the future.”

Also Eugene SMRC AT Research Institute Director Lim Seong-bin said, “With this development, we have created a part that is superior in all aspects including quality, cost, and weight reduction,” and added, “We will strengthen our competitiveness not only in the domestic market but also in overseas markets through mass production in the future.”

Meanwhile, this study was conducted with the support of the 'Automobile Industry Technology Development (Green Car)' project of the Ministry of Trade, Industry and Energy and the Korea Institute of Industrial Technology Evaluation and Planning.