A connection pipe (7), for the fluidic connection of a muffler housing (5) of an active muffler (4) with an exhaust gas-carrying pipe (3) of an exhaust line (2) of an exhaust system (1) for an internal combustion engine, of a motor vehicle, has a pipe wall (8), which envelopes a connection space (9) leading from the muffler housing to the exhaust pipe. A cooling pipe (14), through which a coolant can flow, has an inlet section (15) and an outlet section (16) and is arranged in the connection space. The inlet section (15) passes through the pipe wall (8), whereby a coolant inlet (17), through which coolant can enter the cooling air pipe, is arranged outside the connection pipe (7). The outlet section passes through the pipe wall, whereby a coolant outlet (19), through which coolant can escape from the cooling pipe, is arranged outside the connection pipe (7).

A novel pipe cover is disclosed that can suppress thermal deterioration in a member that is positioned opposite to the pipe, and can control the temperature inside the pipe within a given range, even when a high-temperature fluid circulates through the pipe. The pipe cover is used to cover the outer periphery of a pipe, and includes a base that is formed of a tubular heat insulator, and a surface member that covers the outer surface of the base, a heat radiation section and a heat radiation-suppressing section being provided on the outer surface of the surface member, and the emissivity of the heat radiation section at a wavelength of 2 to 15 m being higher than the emissivity of the heat radiation-suppressing section at a wavelength of 2 to 15 m.

A water drainage assembly for an aftertreatment system includes: a first tube configured to be coupled to an outlet conduit of the aftertreatment system; a second tube having a first end coupled to an outer surface of the first tube, a second end opposite the first end, and an intermediate portion located between the first end and the second end; and a baffle plate located in the second tube. The intermediate portion of the second tube surrounds an end portion of the first tube such that a volume is defined between the end portion of the first tube and the intermediate portion of the second tube. The second tube comprises a drain port configured to allow water to drain from the volume defined between the end portion of the first tube and the intermediate portion of the second tube.

An exhaust purification apparatus capable of improving stirring property of urea water and properly cooling an injection device is provided. The exhaust purification apparatus that purifies nitrogen oxides in exhaust gas includes an exhaust pipe that causes exhaust gas discharged from an engine to flow, a catalyst reactor (catalyst) provided in the exhaust pipe to reduce the nitrogen oxides in the exhaust gas, a through pipe provided in such a way as to penetrate the exhaust pipe, and an injection device provided inside the through pipe to inject a reducing agent for reducing exhaust gas into the exhaust pipe.