Patent ID: 6250339
Filing Date: 2001-06-26
Classification: F16L,F24F

Abstract:
A sound-absorbing and heat-insulating duct comprising:a cylindrical nonwoven cloth layer formed by winding spirally a nonwoven cloth, adjacent side edges of said nonwoven cloth being abutted or overlapped to form a bonding portion;a wire-shaped reinforcing core made of hard synthetic resin material, wound spirally on an outer circumferential surface of said bonding portion, an inner circumference surface of said duct with a substantially smooth cylindrical shape being formed of said spirally wound nonwoven cloth welded to or bonded with said resin reinforcing core;a foam strip layer formed by winding spirally a foam resin strip having a width approximately equal to a width of said nonwoven cloth, both edges of the foam resin strip being disposed on adjacent reinforcing cores respectively;a bonding resin applied to a side surface of the foam strip and a part of said reinforcing core; anda cylindrical resin-coating layer provided to cover an outer circumferential surface of the foam strip layer.