The demand for always lighter vehicles is leading the automotive industry to rethink to the production materials in use: we talked about it with Sanpo Gomu, manufacturer of acoustic insulation parts for OEMs.
August 4, 2020
The demand for ever lighter vehicles is leading the automotive industry to rethink production materials: we talked about it with Sanpo Gomu, a Japanese manufacturer of acoustic insulation parts for OEMs.
The automotive industry is changing rapidly: new trends are emerging and new materials are replacing those used until now. The need of OEMs to produce ever lighter vehicles is leading to rethinking materials, even for acoustic insulation: suppliers must now meet new standards for high performance and lightness.
A trend that began over a decade ago, explained by Noriaki Yamamoto (Director of the technology department) and Daiji Sato (technical development engineer) of Sanpo Gomu: “In 2008, OEMs that were using Sanpo Gomu gaskets and rubber products started demanding new materials, lighter than rubber: among the possible materials, we chose PU because of its better sound insulation performance.”
From rubber to polyurethane for automotive components
“Originally, the material used for radiator insulation was EPDM rubber, a high-density synthetic rubber with good dynamic and mechanical properties. But the demand by OEMs for better insulation performance, especially acoustic, made us test, and then choose, polyurethane. This material, in fact, in addition to having excellent insulating properties, is easy to handle: its density is precisely controllable and this allows us to produce different insulating parts with different densities, to maintain high levels of product quality and to achieve good savings in terms of production costs,” explained Mr. Yamamoto.
The transition from rubber to polyurethane, for producing some automotive insulating components, required nearly five years of work for Sanpo Gomu.
In partnership with their chemical supplier, and using a Cannon dosing unit, the company developed the most suitable formulations to meet its customers’ needs, studying possible applications and markets.
“Different OEMs have different approach to insulation: truck, industrial and commercial vehicle manufacturers are focus on polyurethane because of its good sound deadening properties. Passenger car manufacturers, instead, while using polyurethane for acoustic insulation too, have passenger safety and weight reduction as their primary objectives.”
Using polyurethane in production allowed Sanpo Gomu not only to respond to specific requests from its clients, but also to significantly expand its product portfolio. They have since developed sound deadening parts with film, achieving two results: eliminating the need of a release agent inside the mold and protecting the PUR foam for long-lasting performance.
A fruitful relationship
Sanpo Gomu met Cannon about ten years ago, during their experimentation with using polyurethane as a production material: the A-Compact dosing machine we supplied, thanks to a special configuration that made it suitable for laboratory use, proved excellent for fine-tuning their formulations.
A new Cannon machine has been delivered and will be used for producing PUR insulation parts for trucks radiators.
“Cannon products are very competitive both in terms of performances and price: we chose a Cannon machine to develop chemical formulations, and we are very satisfied with its performance. For this reason, we renewed our trust in the company and bought another dosing unit,” stated Mr. Yamamoto.
Furthermore, the reactivity of Nippon Cannon (Cannon local unit in Japan), and its technical and commercial competence, effectively supported Sanpo Gomu in developing its projects.
The future of polyurethane in the automotive industry
The direction taken by the automotive market is towards electric vehicles.
Polyurethane will evolve thanks new blowing agents and fillers, and even more attention paid to fire proofness, especially for acoustic insulation parts in the engine compartment. All are opening the path to developing new formulations.
Sanpo Gomu’s attitude to innovation and experimentation is leading them to develop new formulations capable of supporting ever better performances, spreading the use of polyurethane to new car components’ production: “The experience and know-how acquired with the development of insulating parts can be exchanged and applied to the realization of other products, such as shock absorbers, in polyurethane too”, said Daiji Sato.
Similarly, the use of polyurethane parts as insulators in trucks, which is not widespread, will be intensified thanks to their excellent sound-insulating qualities.
The market for these types of PUR parts is small and highly competitive: Sanpo Gomu has made innovation its trump card for facing critical industry issues and being at the forefront.
About Sanpo Group
Established in 1952 in Japan as a specialized manufacturer of industrial rubber, Sanpo Gomu produces insulation parts for OEM making heavy trucks and passenger vehicles. The company has three locations in Japan: the Tokyo headquarter, the Ibaraki and Tochigi manufacturing centers. One production plant is in Indonesia. Polyurethane parts production is at the Ibaraki factory.
