A manufacturing process for applying spray-type poly-urethane material is developed for dash isolation pad’s heavy layer. With the manufacturing process, thickness of heavy layer of dash isolation pad could be varied locally. In this study, the soun...
A manufacturing process for applying spray-type poly-urethane material is developed for dash isolation pad’s heavy layer. With the manufacturing process, thickness of heavy layer of dash isolation pad could be varied locally. In this study, the sound insulation performance of the material had been studied in the material level. The weak areas of engine-noise transmission were found experimentally for a target vehicle. By increasing heavy layer’s thickness at the noise-transmission weak areas and decreasing the thickness at the non-weak areas, the noise-transmission was refined and the total weight was also reduced. It is expected that the developed material and manufacturing process could contribute to weight and cost reduction of sound packages.